Asia–Pacific tropical sea cucumber aquaculture - ACIAR

Asia–Pacific tropical 

sea cucumber 

aquaculture 

ACIAR PROCEEDINGS 136

Asia–Pacific tropical 

sea cucumber aquaculture 

Proceedings of an international symposium held in 

Noumea, New Caledonia, 15–17 February 2011 

Editors: Cathy A. Hair, Timothy D. Pickering and David J. Mills 

2012

The Australian Centre for International Agricultural Research (ACIAR) was established in 

June 1982 by an Act of the Australian Parliament. ACIAR operates as part of Australia’s 

international development cooperation program, with a mission to achieve more productive 

and sustainable agricultural systems, for the benefit of developing countries and Australia. 

It commissions collaborative research between Australian and developing-country 

researchers in areas where Australia has special research competence. It also administers 

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Where trade names are used this constitutes neither endorsement of nor discrimination 

against any product by ACIAR. 

© Australian Centre for International Agricultural Research (ACIAR) 2012 

This work is copyright. Apart from any use as permitted under the Copyright Act 

1968, no part may be reproduced by any process without prior written permission 

from ACIAR, GPO Box 1571, Canberra ACT 2601, Australia, aciar@aciar.gov.au 

Hair C.A., Pickering T.D. and Mills D.J. (eds) 2012. Asia–Pacific tropical sea cucumber 

aquaculture. Proceedings of an international symposium held in Noumea, New 

Caledonia, 15–17 February 2011. ACIAR Proceedings No. 136. Australian Centre for 

International Agricultural Research: Canberra. 209 pp. 

ACIAR Proceedings - ISSN 1038-6920 (print), ISSN 1447-0837 (online) 

ISBN 978 1 921962 34 9 (print) 

ISBN 978 1 921962 35 6 (online) 

ACIAR PROCEEDINGS SERIES 

This series of publications includes the full proceedings of research 

workshops or symposia organised or supported by ACIAR. Numbers 

in this series are distributed internationally to selected individuals 

and scientific institutions, and are also available from ACIAR’s 

website at . The papers in ACIAR Proceedings 

are peer reviewed. 

Technical editing by Mason Edit, Adelaide, Australia 

Design by Clarus Design Pty Ltd, Canberra, Australia 

Printing by Canprint Communications Pty Ltd, Canberra, Australia 

Cover: Adult sandfish, Goulburn Island, Northern Territory, Australia. 

(Photo: Wayne Tupper)

Foreword 

Stocks of high-value sea cucumber species have been overexploited throughout the 

Asia–Pacific region. Their high value as a food and medicine in China and other 

parts of Asia, the ease of capture, the apparently insatiable demand for them and 

the lack of effective management indicate that this situation is unlikely to change 

any time soon. Better fisheries governance must be a priority; however, in many 

cases, the situation is beyond the point where improved management alone can 

restore populations. 

Sea cucumber aquaculture is a recurring priority in development aspirations for 

Asian and Pacific island nations, driven by the depletion of stocks from overfishing 

and the subsequent loss of livelihoods and export dollars. Fortunately, for a small 

number of species, aquaculture and farming activities can assist in conserving wild 

stocks, while also generating income and boosting natural recovery. Consequently, 

there has been considerable research on the culture of tropical sea cucumbers in 

the past two decades. 

In 2003 the United Nations Food and Agriculture Organization (FAO) held a 

large workshop on the advances in sea cucumber aquaculture and management in 

Dalian, China—the first of its kind for research in this field. Today, there is still 

enormous interest in the topic, and the research has reached a critical juncture. 

In the Asia–Pacific region, most studies have concentrated on the ‘sandfish’ 

(Holothuria scabra). Large numbers of juveniles can be reliably produced in 

hatcheries using relatively simple techniques, and these can be on-grown and 

transferred to ponds or suitable inshore marine habitats where they can reach 

commercial size in 1–3 years. The Australian Centre for International Agricultural 

Research (ACIAR) has provided significant, long-term research investment into 

sandfish culture in the region (primarily through the WorldFish Center). Projects 

have investigated large-scale hatchery culture of sandfish (Solomon Islands), 

techniques for releasing cultured juveniles into the wild (New Caledonia), and 

sea ranching and pond culture (the Philippines, Vietnam and Australia). 

It is timely to review this work, together with recent research from other parts 

of the world, in order to encourage collaboration and technology transfer, and 

to develop an effective way to ensure that the technology can deliver real benefits 

to poor rural communities. To this end, ACIAR, in collaboration with the 

Secretariat of the Pacific Community (SPC), organised a symposium on tropical 

sea cucumber aquaculture at SPC Headquarters in Noumea, New Caledonia, in 

February 2011. Although the principal focus was on ACIAR work, particularly 

in the Asia–Pacific region, researchers from other parts of the world were invited 

to provide additional expertise. 

3

The symposium identified knowledge gaps and highlighted researchable topics 

for future developments in sea cucumber aquaculture. These proceedings will be 

a valuable resource for all practitioners in this field. 

Nick Austin 

Chief Executive Officer 

ACIAR 

4

Contents 

Foreword 3 

Abbreviations 9 

Acknowledgments 10 

Regional overviews 11 

Overview of sea cucumber aquaculture and stocking research in the Western 

Pacific region 12 

Robert A. Jimmy, Timothy D. Pickering and Cathy A. Hair 

Overview of sea cucumber aquaculture and sea-ranching research in the 

South-East Asian region 22 

David J. Mills, Nguyen D.Q. Duy, Marie Antonette Juinio-Meñez, 

Christina M. Raison and Jacques M. Zarate 

Sea cucumber hatchery production 33 

Large-scale sandfish production from pond culture in Vietnam 34 

Nguyen D.Q. Duy 

In-vitro fertilisation: a simple, efficient method for obtaining sea cucumber 

larvae year round 40 

Igor Eeckhaut, Thierry Lavitra, Aline Léonet, 

Michel Jangoux and Richard Rasolofonirina 

Evaluation of nutritional condition of juvenile sandfish (Holothuria scabra) 50 

Satoshi Watanabe, Jacques M. Zarate, Maria J.H. Lebata-Ramos 

and Marie F.J. Nievales 

Ocean nursery systems for scaling up juvenile sandfish (Holothuria scabra) 

production: ensuring opportunities for small fishers 57 

Marie Antonette Juinio-Meñez, Glycinea M. de Peralta, Rafael Junnar 

P. Dumalan, Christine Mae A. Edullantes and Tirso O. Catbagan 

Small-scale hatcheries and simple technologies for sandfish (Holothuria scabra) 

production 63 

Ruth U. Gamboa, Remie M. Aurelio, Daisy A. Ganad, 

Lance B. Concepcion and Neil Angelo S. Abreo 

5

Sandfish production and development of sea ranching in northern Australia 75 

William M. Bowman 

Hatchery experience and useful lessons from Isostichopus fuscus in Ecuador 

and Mexico 79 

Annie Mercier, Roberto H. Ycaza, Ramon Espinoza, 

Victor M. Arriaga Haro and Jean-François Hamel 

Sandfish sea ranching and farming 91 

Principles and science of stocking marine areas with sea cucumbers 92 

Steven W. Purcell 

Pond grow-out trials for sandfish (Holothuria scabra) in New Caledonia 104 

Natacha S. Agudo 

Ability of sandfish (Holothuria scabra) to utilise organic matter in black tiger 

shrimp ponds 113 

Satoshi Watanabe, Masashi Kodama, Jacques M. Zarate, 

Maria J.H. Lebata-Ramos and Marie F.J. Nievales 

Establishment and management of communal sandfish (Holothuria scabra) 

sea ranching in the Philippines 121 

Marie Antonette Juinio-Meñez, Marie Antonette S. Paña, Glycinea M. de Peralta, 

Tirso O. Catbagan, Ronald Dionnie D. Olavides, Christine Mae A. Edullantes 

and Bryan Dave D. Rodriguez 

Maldives sea cucumber farming experience [Abstract only] 128 

Beni G.D. Azari and Grisilda Ivy Walsalam 

Sandfish (Holothuria scabra) production and sea-ranching trial in Fiji 129 

Cathy A. Hair 

Sea cucumber farming experiences in south-western Madagascar 142 

Georgina Robinson and Benjamin Pascal 

Sea ranching of sandfish in an Indigenous community within a well-regulated 

fishery (Northern Territory, Australia) 156 

Ann E. Fleming 

Resource tenure issues 161 

Marine tenure and the role of marine protected areas for sea cucumber 

grow-out in the Pacific region 162 

Semisi V. Meo 

Sandfish (Holothuria scabra) fisheries in the Pacific region: present status, 

management overview and outlook for rehabilitation 168 

Kalo M. Pakoa, Ian Bertram, Kim J. Friedman and Emmanuel Tardy 

6

Market potential and challenges for expanding the production of sea cucumber 

in South-East Asia 177 

Maripaz L. Perez and Ernesto O. Brown 

Understanding the sea cucumber (beche-de-mer) value chain 

in Fiji and Tonga 189 

Theo A. Simos 

Processing cultured tropical sea cucumbers into export product: 

issues and opportunities [Abstract only] 195 

Steven W. Purcell and Nguyen D.Q. Duy 

Sandfish (Holothuria scabra) farming in a social–ecological context: 

conclusions from Zanzibar 196 

Hampus Eriksson 

World sea cucumber markets: Hong Kong, Guangzhou and New York 203 

Jun Akamine 

Applying economic decision tools to improve management and profitability 

of sandfish industries in the Asia–Pacific region 205 

Bill L. Johnston 

7

1-MeA 1-methyladenine 

ACIAR Australian Centre for 

International Agricultural 

Research 

Aj-GSSL Apostichopus japonicus 

gonad-stimulating substancelike 

(molecule) 

AVS acid-volatile sulfur 

BL body length 

BML Bolinao Marine Laboratory 

BV body volume 

BW body weight 

CFD coelomic fluid density 

CFV coelomic fluid volume 

CFW coelomic fluid weight 

CMT customary marine tenure 

DMP dimercaptopropanol 

DO dissolved oxygen 

DTT dithiothreitol 

EDTA ethylenediaminetetraacetic 

acid 

FSM Federated States of 

Micronesia 

GMP good management practice 

GSS gonad-stimulating substance 

GSSL gonad-stimulating 

substance-like 

GSSL-IVF gonad-stimulating substancelike 

in-vitro fertilisation 

(technique) 

GVBD germinal vesicle breakdown 

HACCP hazard analysis critical 

control point 

ind individuals 

IVF in-vitro fertilisation 

LMMA locally managed marine area 

Abbreviations 

9 

MPA marine protected area 

MH-IVF IVF technique developed at 

Madagascar Holothurie S.A. 

MH.SA Madagascar Holothurie 

Société Anonyme 

MIS maturation inducing 

substance 

NGO non-government organisation 

NPV net present value 

NT Northern Territory 

OFCF Overseas Fishery Cooperation 

Foundation (Japan) 

OMI oocyte maturation inductor 

PCF perivisceral coelomic fluid 

PICs Pacific island countries 

PICTs Pacific island countries and 

territories 

PNG Papua New Guinea 

RIA3 (Vietnamese) Research 

Institute for Aquaculture No. 3 

SD standard deviation 

SE standard error 

SEAFDEC–AQD Southeast Asian Fisheries 

Development Center – 

Aquaculture Department 

SPC Secretariat of the Pacific 

Community 

TMD Trans’Mad-Développement 

UPMin University of the Philippines 

Mindanao 

UPMSI University of the Philippines 

Marine Science Institute 

USP University of the South 

Pacific 

UVSW UV-treated sea water 

WorldFish WorldFish Center

Acknowledgments 

The symposium was made possible through funding from the Australian 

Centre for International Agricultural Research (ACIAR) and the Secretariat of 

the Pacific Community (SPC). Particular thanks to Dr Chris Barlow, ACIAR 

Fisheries Program Leader, who originally suggested convening a group of experts 

to review the status and future of tropical sea cucumber aquaculture research. 

We also wish to acknowledge Mike Batty and Robert Jimmy of SPC for their 

invaluable support and in-kind assistance, including providing the venue for the 

symposium (the Jacques Iekawé Conference Centre at the SPC headquarters in 

New Caledonia) and use of the secretariat. Various SPC staff members assisted 

with other important tasks—thanks go to the translation team, the travel desk and 

the information section. In particular, we thank Genevieve Mirc, who worked tirelessly 

to smooth the way for international participants and coordinate the logistics 

associated with holding the symposium. We extend our gratitude to Aymeric 

Desurmont for preparing the symposium website and Mrs Helena Heasman for 

producing the book of abstracts. The symposium was chaired by Dr Geoff Allan 

(of ACIAR at that time) and Dr Tim Pickering (SPC). We appreciate the efforts of 

several colleagues who also provided support and advice before, during and after 

the symposium, especially Dr Steven Purcell of the Southern Cross University’s 

National Marine Science Centre. 

We thank all the participants for their enthusiasm, and for freely sharing their 

expertise and ideas to make the symposium a success. Their combined efforts 

show the way forward for the next decade of research into the dynamic and 

promising field of culture and grow-out of sea cucumbers for improved livelihoods 

of coastal communities. 

Photographs are by the author(s) of papers unless otherwise stated. 

10

Regional overviews 

Farmers gutting cultured sandfish after harvesting from ponds in 

Van Ninh, central Vietnam (Photo: David Mills) 

11

Overview of sea cucumber aquaculture and 

stocking research in the Western Pacific region 

Robert A. Jimmy 1*, Timothy D. Pickering 1 and Cathy A. Hair 2 

Abstract 

Sea cucumbers represent an important income source to coastal communities in many Pacific islands, but 

is now worth only a fraction of historical values. Sea cucumbers have been harvested for hundreds of years 

for trade with Asia and were probably one of the first real ‘exports’ from the Pacific islands. Unfortunately, 

the increase in demand and price, combined with the development of cash economies and growing coastal 

populations in many islands, has led to widespread overfishing of the resource across much of this region. 

There is a high level of interest in adoption of aquaculture techniques to restore production levels, but 

different capacity levels require implementation of different techniques. Some Pacific island countries and 

territories have completed successful research trials of hatchery and release techniques, and now have 

capacity to scale up this activity. Factors that work in favour of successful aquaculture include pristine marine 

environments, long familiarity with sea cucumbers as a commodity, and traditional marine tenure systems 

that in some places can provide a basis for management of released sea cucumbers. Challenges include lack 

of technical capacity, unproven effectiveness of sea cucumber releases and poaching. 

Introduction 

On 14 February 2011, prior to the Asia–Pacific 

Tropical Sea Cucumber Symposium, Noumea, official 

representatives of Pacific island countries and territories 

(PICTs) that are members of the Secretariat of the 

Pacific Community (SPC) met to discuss sea cucumber 

resources and aquaculture. This paper represents a 

synthesis of their status, and was presented on the first 

day of the symposium. When participants’ experiences 

were compared and discussed, a number of common 

themes emerged: 

• Sea cucumber represents an important income 

source to coastal communities in many Pacific 

islands. Sea cucumbers have been harvested for hundreds 

of years for trade with Asia and were probably 

one of the first real ‘exports’ from the Pacific islands. 

1 Secretariat of the Pacific Community, Noumea Cedex, 

New Caledonia 

* Corresponding author: 

2 James Cook University, Townsville, Queensland, Australia 

12 

• This is mainly an export market commodity, but it is 

also a subsistence food fishery in some Pacific island 

countries and communities; for example, as a whole 

cooked sea cucumber, as ‘sashimi’ (sliced raw meat), 

or as marinated guts and gonads in salt and lime. 

• Catches from the Asian and Pacific regions are 

known to be the highest, with about 36 species 

being harvested in the Pacific region. 

• Stocks are under heavy pressure with increases in 

demand and price, combined with the development 

of cash economies and growing coastal populations 

in many islands. This has led to widespread overfishing 

of the resource across much of this region. 

Through time, smaller individuals and lower valued 

species are forming a steadily increasing proportion 

of the total catch. 

• Management of the fishery has essentially failed, 

for a number of reasons. PICTs are resorting to 

the extreme measure, and ‘blunt instrument’ 

management, of imposing fishing moratoria for 

extended periods (years at a time) to bring about 

stock recovery.

• Concern about overexploitation has led to initiatives 

to promote sea ranching and restocking as an 

income-generating activity and a means to increase 

the production of wild stocks. 

PICT status reports 

Although there are similarities, differences also exist 

between PICTs—both in the species of interest for 

sea cucumber aquaculture and in the level of capacity 

to implement aquaculture techniques to increase production. 

A number of PICTs have made progress on 

sea cucumber aquaculture on a few key species. Key 

points about the main PICTs involved or interested in 

sea cucumber aquaculture are summarised in Table 1. 

Research in PICTs 

Despite the majority of PICTs having limited capacity 

for research and development of sea cucumber 

aquaculture, it is worth highlighting the notable 

exceptions where targeted research effort has been 

made. The countries with some history or current 

activity in the area are Kiribati, Federated States of 

13 

Micronesia (FSM), Palau, Fiji, Solomon Islands and 

New Caledonia. Sandfish continues to be the focus 

of research and development activity in FSM, Fiji 

and New Caledonia. Substantial research was done in 

the late 1990s in Solomon Islands on sandfish culture 

(e.g. Battaglene et al. 1999), but Japan is now funding 

research into peanutfish or dragonfish (Stichopus 

horrens) production. Kiribati is the first (and only) 

country to consistently produce high-value white 

teatfish (Holothuria fuscogilva) juveniles (Friedman 

and Tekanene 2005; Purcell and Tekanene 2006) 

(Figure 1). Since 2009, Palau has produced surf 

redfish and hairy blackfish (Actinopyga mauritiana 

and A. miliaris) both medium-value sea cucumber 

species. In all the PICTs active in sea cucumber 

production, the emphasis is currently on production 

technology that has been provided either by private 

investment (e.g. Palau and FSM, Yap) or through the 

efforts of overseas aid assistance and government 

support (e.g. Kiribati, Fiji, Solomon Islands, FSM, 

New Caledonia). Hatcheries are being built, and staff 

are being trained or technicians imported in some 

cases to boost capacity. 

Figure 1. Cultured white teatfish juveniles produced at Tanaea hatchery, Kiribati (Photo: Antoine Teitelbaum)

Table 1. Summary of sea cucumber aquaculture in Pacific island countries 

Country Availability of high-interest 

species 

Fiji White teatfish 

Sandfish 

Federated States of 

Micronesia (FSM) 

White teatfish 

Sandfish 

Actinopyga spp. 

Lollyfish 

Black teatfish 

14 

History of sea cucumber 

aquaculture 

ACIAR sandfish hatchery 

mini-projects at Savusavu 

(Vanua Levu island) and 

Galoa (Viti Levu island) 

First spawning started in 

2009, training also provided 

to community wardens 

Hatchery-based releasing 

project for sandfish and 

black teatfish, College of 

Micronesia, Land Grant 

Program, Pohnpei 

Private hatchery and 

sea ranching in Yap for 

Actinopyga spp. 

1 staff was trained in Fiji 

in 2008 (ACIAR), and has 

transferred their knowledge 

to other staff 

Kiribati White teatfish Overseas Fishery 

Cooperation Foundation 

of Japan (OFCF) hatchery 

projects, initiated in 1995, 

started production in 1997, 

and released about 10,000 

sea cucumbers per year 

from 1999–2004 and again 

in 2008–09 

ACIAR research on release 

strategies 

New Caledonia White teatfish 

Sandfish 

Black teatfish 

Large WorldFish–ACIAR 

St. Vincent Project on 

juvenile grow-out, release 

techniques and pond trials 

(2001–07) 

National strategy 

Fisheries Department 

aquaculture priority 

included in work plan from 

2011 

A regulation on sea 

cucumber is in place. 

Sandfish are reserved for 

subsistence fishery and 

prohibited from export 

National Aquaculture 

Strategy (2002) identified 

sea cucumber as a priority 

for development 

Yap: there is a regulation on 

licensing system in place 

Pohnpei: all harvests 

banned since 1995 

Kosrae: all exports banned 

Chuuk: intensive fishing 

activity, and no sea 

cucumber fisheries 

management systems are 

in place 

Government wishes to 

develop white teatfish 

further 

No specific legislation for 

sea cucumber 

Sea cucumber fishery 

management plan currently 

formulated 

Wish to introduce sandfish 

because it is more suitable 

than white teatfish for 

culture in ponds 

Government is supporting 

development with pilot 

projects and research for 

sandfish

Hatchery capacity Community-based 

management capacity 

Private blacklip pearl oyster 

hatchery (Savusavu) with 

micro-algae culture facility 

Government shrimp 

hatchery (Galoa) with 


Seawater laboratory at the 

University of the South 

Pacific in Suva, with 


Government and privatesector 

staff trained on 

sandfish under ACIAR 

project, and on micro-algae 

Functional hatchery at 

College of Micronesia in 

Pohnpei 

There has been a hatchery 

facility in Yap since 2007 

(Actinopyga spp.) 

There is a private hatchery 

in Chuuk 

Kosrae National 

Aquaculture Centre has a 


White teatfish hatchery 

Government pearl oyster 

hatchery 

One private sea 

cucumber hatchery under 

construction, and another 

being proposed 

Have six shrimp hatcheries 

and two for finfish 

Fiji Locally-Managed 

Marine Area Network 

projects in Fiji: 259 

registered marine protected 

areas (MPAs) 

Natuvu village in 

Cakaudrove province 

created an MPA especially 

for sandfish restocking 

(2008) 

MPAs are getting support, 

and communities are 

now requesting that those 

MPAs be stocked with sea 

cucumber 

No community-based MPA 

in Gilbert and Line groups, 

only the Phoenix Islands 

Protected Area 

A few community-based 

fisheries management 

(CBFM) plans 

23 MPAs in Province Sud 

and 4 in Province Nord 

CBFM in one community 

Broodstock 

availability 

Sandfish are 

available, although 

there is localised 

scarcity 


availability is 

unknown but 

probable 

15 

Availability in Yap 

and Pohnpei, with 

sufficient sandfish in 

the wild. Often used 

100–200 adults for 

spawning 

Kosrae and Chuuk 

not surveyed but 

likely to be the same 


becoming difficult 

to find 

Sandfish are not 

present in Kiribati, 

so for aquaculture to 

become possible it 

would first need to be 

introduced 

Still have good 

stocks, both in and 

out of MPAs, but high 

variability between 

sites 

Genetic survey of 

broodstock has been 

conducted 

Constraints 

Government micro-algae 

production facility and expertise 

needs upgrading 

Need for more people to be 

trained on seed production and 

grow-out 

Lack of local investors 

Lack of skills and local 

technicians, so there is reliance 

on foreign technicians 

Need for better communication 

between national and local 

governments, private sector and 

traditional tenure holders 

Scarcity of broodstock, so they 

are kept in captivity 

White teatfish are not suitable for 

pond culture 

High mortality rate during 

juvenile stage 

Release effectiveness unknown 

Very difficult to monitor 

post-release juveniles 

High staff turnover, so a 

continual need for training 

Spawning season may be limited 

by cold temperature 

Production and grow-out 

economic assessment needed 

Expert advice sought on 

protocols, especially grow-out 

Need to develop tagging methods 

for monitoring (sea ranching and 

restocking) 

Availability of juveniles for 

restocking and enhancement may 

be limited by hatchery capacity 

continued …

Table 1. (continued) 

Country Availability of highinterest 

species 

Palau White teatfish 

Sandfish 

Surf redfish 

Blackfish 

Papua New Guinea White teatfish 

Sandfish 

Samoa White teatfish 

Dragonfish (Stichopus 

horrens) are targeted by the 

fishery 

Sandfish not present in 

Samoa 

Solomon Islands White teatfish 

Sandfish 

Peanutfish (dragonfish (S. 

horrens)) to be targeted in 

a new project developed by 

Japan (OFCF) 

Tonga White teatfish 

Golden sandfish 

Vanuatu White teatfish 

Sandfish 

16 

History of sea 

cucumber aquaculture 

Has had a project 

since 2009 producing 

Actinopyga mauritiana 

and A. miliaris 

National strategy 

Government aims to develop 

sea cucumber aquaculture 

None Priority species, especially 

since sea cucumber harvest 

moratorium imposed 

None Sea cucumber restocking is 

in the Aquaculture Section 

Workplan for 2011–15 

(subject to hatchery) 

Government’s current main 

priority is management of 

the sea cucumber fishery 

A private-sector initiative 

to introduce sandfish for 

aquaculture is now underway 

Ban on commercial harvest 

for export of any sea 

cucumber species, ban on 

harvest within reserves 

Large WorldFish–ACIAR 

project on hatchery 

techniques (1996–2000) 

One of four priorities 

government wishes to 

develop, according to 

2009 National Aquaculture 

Development Plan 

None Aquaculture Plan identifies 

sea cucumber species as 

highest priority. 

Sea cucumber plan (2009) in 

place for the fishery 

Two imports of hatchery 

juveniles of sandfish from 

Australia (2006–07), but 

have not been effective 

Sea cucumber aquaculture 

identified as a priority in 

the National Aquaculture 

Strategy 

Draft sea cucumber fishery 

management plan in place 

Moratorium on export in 

place for 5 years since 2008

Hatchery capacity Community-based 

management capacity 

Palau has expertise in 

producing surf redfish and 

blackfish 

Palau Community College 

has a hatchery under the 

Land Grant System 

Private pearl and shrimp 

hatcheries 

New government 

multispecies hatchery at 

Kavieng 

Clam hatchery has been 

decommissioned. Does not 

have a mariculture hatchery 

facility at the moment. 

Proposed new hatchery not 

built yet 

WorldFish Center Nusa 

Tupe clam hatchery 

OFCF–government sea 

cucumber (peanutfish) 

hatchery has four local 

technical staff, but they 

need training on sea 


Trained on sandfish in 

2008 under ACIAR at 

Department of Primary 

Industries in Cairns 

Clam and pearl oysters 

produced at Sopu 

government hatchery 

New micro-algae facility in 

place but not yet operating 

Private shrimp hatchery 

Government clam/trochus 

hatchery 

There is active support for 

MPAs (e.g. HOPE Network) 

PNG Centre for Locally 

Managed Areas is active in 

New Britain and New Ireland 

Current moratorium on 

fishing will benefit release 

activities 

History of community-based 

management since 1995 

(fisheries by-laws) 

Good success with trochus 

introduction and stocking 

onto reefs 

54 village-level reserves, 2 

district-level MPAs and 84 

village CBFMs currently 

effective 

Three main active MPAs in 

place 

Solomon Islands Locally 

Managed Marine Areas 

Network and World Wildlife 

Fund both active in engaging 

with communities 

History of community-based 

management 

Special Management 

Areas in place since 2002, 

regulation in 2008 

Traditional community-based 

tabu areas (closed to fishing 

or harvesting) and MPAs are 

in place (e.g. Village Based 

Resource Managed Areas 

Network) 

Customary Marine Tenure 

very active but commercial 

pressures intense 

17 

Broodstock 

availability 

Unknown but 

probably available, as 

for Pohnpei and Yap 

Available, although 

overfishing will have 

reduced numbers of 

large animals 

Sandfish not present 

in Samoa 

White teatfish and 

other high-value 

species in good sizes 

very scarce 

Sandfish available. 

Severe overfishing 

has probably 

limited broodstock 

availability, but this 

needs a survey 

Broodstock for 

peanutfish readily 

available and will be 

collected from the 

three MPA sites 

Constraints 

No specific technical skills base 

for sea cucumber. Project run 

by Korean technicians 

Lack of micro-algae production 

facility and expertise 

No specific expertise for sea 


No specific expertise for 

micro-algae production 





Low biomass of high-valued 

species based on previous 

surveys 



Peanutfish is a new species 

for aquaculture, so not much 

information about it yet 

Sandfish available MPAs are not very effective due 

to enforcement problems 

Micro-algal unit not yet 

operating due to lack of funds. 

Probably okay 

Will conduct a 

survey in 2011–12 to 

determine stock status 





Lack of hatchery space

Fiji, Palau, Kiribati and New Caledonia have 

released locally cultured juvenile sea cucumbers into 

the wild, and cultured juveniles from Australia have 

been released in Vanuatu. Although Kiribati has had 

success in the spawning and rearing of white teatfish, 

there has been high mortality of juveniles in the 

hatchery. For those that reach release stage, it has been 

established that fluorochrome marking can successfully 

distinguish them from wild animals (Purcell and 

Blockmans 2009). However, their highly cryptic nature 

and the lack of appropriate release strategies have constrained 

efforts in that area. Despite the release of tens 

of thousands of juveniles of approximately 10 mm 

length on numerous occasions, monitoring for survival 

and growth has been unsuccessful. Recent attempts 

to release into enclosures failed due to storms that 

destroyed the pens (Teitelbaum and Aram 2010). In 

another project, over three million juvenile A. mauritiana 

and A. miliaris were produced and released into 

the wild in three states in Palau. However, the success 

of this release program is unknown. The results of a 

small pilot release of juvenile sandfish in Fiji were 

promising (average 28% survival after 6 months and 

18 

166 g size at 8 months: Hair et al. 2011; Hair 2012), 

but the project needs to be scaled up to gain commercial 

confidence in the activity. 

FSM has not released any juveniles yet but the 

College of Micronesia in Pohnpei has developed a 

land-based system (‘habitat simulator’) for long-term 

holding of broodstock and juveniles, which uses a 

combination of flow-through and closed recirculating 

water techniques (Figure 2). Hatchery-produced 

juveniles were used for tagging trials (M. Ito, pers. 

comm., March 2011). In the habitat simulator, tag 

retention rates for larger individuals (ind) were 

70–87% at 2 months (stocking density ~20 ind/m 2 

or ~3,000 g/m 2), while for smaller sandfish it was 

80% at 2 weeks (~8 ind/m 2 or 210 g/m 2). Numbers 

of juveniles were released into enclosures in the wild 

2 months after tagging; retention rates on these are 

to be monitored for a period of 2 years. Batches of 

hatchery-produced juveniles (5,000 × 6 weeks old and 

30,000 × 4 weeks old) are being maintained for largescale 

tagging trials. The project will soon move to a 

restocking program, which will involve mass hatchery 

production of juveniles. 

Figure 2. Habitat simulator system and hatchery technician tagging a cultured sandfish (College of Micronesia, 

Pohnpei, Federated States of Micronesia) (Photo: Masahiro Ito)

Much of our current knowledge regarding sandfish 

grow-out and release strategies was generated from 

research carried out between 2000 and 2006 in New 

Caledonia (e.g. Purcell 2004; Purcell and Simutoga 

2008; Agudo 2012). Private-sector production in 

New Caledonia’s northern and southern provinces 

is currently underway and, once available, cultured 

juveniles will be released into MPAs and grown in 

ponds. The experience from Vanuatu of importing 

juvenile sandfish and releasing them into the wild 

was perhaps unsuccessful because of poor release 

strategies, but information is lacking because postrelease 

monitoring was not undertaken. 

The problems associated with sourcing and holding 

broodstock have been identified as a bottleneck to 

developing sea cucumber aquaculture in a number of 

PICTs. In particular, the scarcity of white teatfish in 

Kiribati continues to constrain their hatchery efforts. 

The high cost of obtaining them and subsequent difficulty 

of keeping them in good spawning condition 

means that new broodstock have to be obtained for 

each hatchery run. This has led them to consider 

importing sandfish, which can be maintained more 

easily in secure pond facilities and which have wellestablished 

release strategies. In Fiji, FSM and New 

Caledonia, there are generally sandfish broodstock 

available, but stock status can be variable between 

locations. This is problematic if responsible release 

practices are being followed, since progeny should 

be released into the area where parent stock originated 

(Uthicke and Purcell 2004; SPC 2009). FSM 

is sourcing broodstock of black teatfish (Holothuria 

whitmaei) with the intention of culturing this species 

in the near future. 

Discussion 

There is universal interest among PICTs in the 

application of aquaculture techniques to increase 

production from sea cucumber resources. The main 

species of interest is sandfish, except in Kiribati 

(white teatfish) and Solomon Islands (peanutfish). 

Two countries that lie outside the natural geographical 

distribution of sandfish (Kiribati and Samoa) have 

expressed interest in introducing it for aquaculture. 

The range of experiences with, and capacities 

in, sea cucumber aquaculture research vary greatly. 

Some PICTs have no capacity or experience at all. 

In others there has been successful completion 

of research projects, from which the capacity to 

produce juveniles in hatcheries for restocking trials 

19 

on a pilot-commercial scale is now established. The 

leading PICTs in sea cucumber research activity to 

date are New Caledonia, FSM and Palau, followed 

by Kiribati, Fiji and Solomon Islands. 

Technical capacity in-country is a vital prerequisite 

for successful sea cucumber aquaculture, but by itself 

it is not enough to guarantee success. The capacity for 

marine tenure systems in PICTs to deliver sufficient 

protection to investment in restocked or ranched sea 

cucumbers is another important consideration. There 

have been some positive experiences with management 

systems based on custom and traditional marine 

tenure, to achieve better conservation of inshore fishery 

resources. Community-based management provides 

one possible basis for protection of released sea 

cucumbers until ready for harvest. However, some 

PICTs have attempted sea cucumber aquaculture for a 

variety of other reasons, often with misguided intentions: 

for example, past experiences include projects 

that were very much investor-driven, with inadequate 

feasibility studies undertaken prior to development. 

The term ‘aquaculture’ can be used misleadingly by 

unscrupulous investors to lead PICT decision-makers 

into accepting an unsustainable development where 

wild stocks can be harvested at the same time as the 

so-called aquaculture is taking place. Policy advice 

and technical assistance are currently being provided 

by the SPC to member countries so that they can 

recognise and assess development proposals that are 

genuine and distinguish those that are purely to lure 

PICTs into allowing access to their wild stock (see 

Pakoa et al. 2012). 

Taking these technical and institutional issues into 

account, the attributes of the Pacific islands region 

that lend themselves to sea cucumber aquaculture can 

be summarised as follows: 

• Pristine marine environments and suitable marine 

habitat are available for restocking and sea ranching 

of priority species of interest. 

• Community-based management systems are in 

place in many areas. 

• Sea cucumber is an ideal commodity for rural and 

maritime community engagement because the 

harvesting techniques are simple, and because sea 

cucumbers do not require large investment capital 

for processing. 

• The sea cucumber industry in this region has a 

history stretching over more than two centuries, so 

it does not require large investment in familiarisation 

or retraining, and it is already well-integrated 

within traditional lifestyles and practices.

• Sea cucumber hatchery requirements are similar 

to those of other species already being cultured in 

the region (e.g. shrimp, pearl, giant clam, trochus), 

so infrastructure can be shared with these other 

commodities. 

The experiences shared by PICTs in sea cucumber 

aquaculture reveal some common challenges, however, 

including the following: 

• In some places it is difficult to find sufficient numbers 

of broodstock-size animals for aquaculture. 

• Expertise in sea cucumber aquaculture is limited. 

• The effectiveness of sea cucumber releases is not 

yet proven: optimal release techniques are still 

being finetuned for some species (e.g. sandfish) 

and are unknown for others (e.g. white teatfish). 

• Land-based nursery areas can be limiting. 

• Land disputes can affect released juveniles and 

broodstock if release sites are open access or under 

dispute. 

• Control and enforcement of restocked or searanched 

populations to prevent poaching can be 

difficult to achieve. 

• The consequences of translocation of juveniles are 

not yet known and could cause irreversible genetic 

problems, so care must be taken to preserve genetic 

integrity wherever possible. 

• There needs to be more research into the economic 

feasibility of restocking. 

Pacific regional priorities for sea cucumber 

aquaculture, to address these challenges and thereby 

enable PICTs to capitalise upon their favourable 

attributes, include: 

• demonstration of the effectiveness of sea cucumber 

restocking and sea ranching through larger scale 

experimental releases and post-release monitoring 

• research to develop optimal release strategies for 

improved survival and growth 

• capacity-building and technology transfer among 

PICTs for sea cucumber aquaculture 

• economic analysis of sea cucumber aquaculture 

and restocking scenarios 

• social analysis of traditional marine tenure systems 

and of the effectiveness of community-based management, 

to identify the best governance and/or 

business models for protection of investment in 

sea cucumber aquaculture. 

20 


The authors wish to thank the following PICT scientists 

and managers, who contributed the information 

provided in this report: Gerald Billings (Fiji Fisheries 

Department); Masahiro Ito (Land Grant, FSM); 

Karibanang Aram (Kiribati Ministry of Fisheries 

and Marine Resources); Claire Marty, Bernard Fao, 

Thomas Requillart and Nathaniel Cornuet (Province 

Nord and Province Sud, New Caledonia); Percy 

Rechelluul (Palau); Jacob Wani (Papua New Guinea 

National Fisheries Authority); Joyce Samuela Ah 

Leong (Samoa); Sylvester Diake Jr (Solomon 

Islands Ministry of Fisheries and Marine Resources); 

Poasi Ngaluafe (Tonga Fisheries) and Jayven Ham 

(Vanuatu Fisheries Department). 

References 

Agudo N.S. 2012. Pond grow-out trials for sandfish 

(Holothuria scabra) in New Caledonia. In ‘Asia–Pacific 

tropical sea cucumber aquaculture’, ed. by C.A. 

Hair, T.D. Pickering and D.J. Mills. ACIAR Proceedings 

No. 136, 104–112. Australian Centre for International 

Agricultural Research: Canberra. [These proceedings] 

Battaglene S.C., Seymour J.E. and Ramofafia C. 1999. 

Survival and growth of cultured sea cucumbers, 

Holothuria scabra. Aquaculture 178, 293–322. 

Friedman K. and Tekanene M. 2005. White teatfish at 

Kiribati sea cucumber hatchery: ‘Local technicians getting 

them out again’. SPC Beche-de-mer Information 

Bulletin 21, 32–33. 

Hair C.A. 2012. Sandfish (Holothuria scabra) production 

and sea-ranching trial in Fiji. In ‘Asia–Pacific tropical sea 

cucumber aquaculture’, ed. by C.A. Hair, T.D. Pickering 

and D.J. Mills. ACIAR Proceedings No. 136, 129–141. 

Australian Centre for International Agricultural 

Research: Canberra. [These proceedings] 

Hair C., Pickering T., Meo S., Vereivalu T., Hunter J. and 

Cavakiqali L. 2011. Sandfish culture in Fiji Islands. SPC 

Beche-de-mer Information Bulletin 31, 3–11. 

Pakoa K., Bertram I., Friedman K. and Tardy E. 2012. 

Sandfish (Holothuria scabra) fisheries in the Pacific 

region: present status, management overview and 

outlook for rehabilitation. In ‘Asia–Pacific tropical sea 

cucumber aquaculture’, ed. by C.A. Hair, T.D. Pickering 

and D.J. Mills. ACIAR Proceedings No. 136, 168–176. 


Research: Canberra. [These proceedings]

Purcell S.W. 2004. Criteria for release strategies and evaluating 

the restocking of sea cucumbers. In ‘Advances in 

sea cucumber aquaculture and management’, ed. by A. 

Lovatelli, C. Conand, S. Purcell, S. Uthicke, J.-F. Hamel 

and A. Mercier. FAO Fisheries Technical Paper No. 463, 

181–191. Food and Agriculture Organization of the 

United Nations: Rome. 

Purcell S.W. and Blockmans B.F. 2009. Effective fluorochrome 

marking of juvenile sea cucumbers for sea 

ranching and restocking. Aquaculture 296, 263–270. 

Purcell S.W. and Simutoga M. 2008. Spatio-temporal and 

size-dependent variation in the success of releasing 

cultured sea cucumbers in the wild. Reviews in Fisheries 

Science 16, 204–214. 

21 

Purcell S. and Tekanene M. 2006. Ontogenetic changes in 

colouration and morphology of white teatfish, Holothuria 

fuscogilva, juveniles in Kiribati. SPC Beche-de-mer 

Information Bulletin 23, 29–31. 

SPC (Secretariat of the Pacific Community) 2009. Use 

of hatcheries to increase production of sea cucumbers. 

Background Paper 4, Sixth SPC Heads of Fisheries 

Meeting, February 2009. Secretariat of the Pacific 

Community. 

Teitelbaum A. and Aram K. 2010. White teatfish aquaculture 

project in Kiribati. SPC Fisheries Newsletter 131, 6–7. 

Uthicke S. and Purcell S. 2004. Preservation of genetic 

diversity in restocking of the sea cucumber Holothuria 

scabra planned through allozyme electrophoresis. 

Canadian Journal of Fisheries and Aquatic Science 61, 

519–528. 

Natuvu (Fiji) community sea ranch warden with sandfish after a cyclone 

(note broken pen in background) (Photo: Cathy Hair)

Overview of sea cucumber aquaculture 

and sea-ranching research in the 

South-East Asian region 

David J. Mills 1, Nguyen D.Q. Duy 2, Marie Antonette Juinio-Meñez 3, 

Christina M. Raison 4 and Jacques M. Zarate 5 

Abstract 

South-East Asia has traditionally been the global centre of production of tropical sea cucumbers for Chinese 

markets. Early research into culture methods took place outside this region, notably in India, the Pacific region 

and China. However, recent investment in Holothuria scabra (sandfish) culture has led to some significant 

advances within this region. The Philippines and Vietnam have been at the forefront of recent efforts, with 

involvement from substantial national programs and local institutions as well as international donors and 

scientific organisations. Smaller programs are ongoing in Thailand, Malaysia and Indonesia. Recent advances 

and simplifications in hatchery techniques are a major step forward, having promoted the development of 

experimental-scale sea-ranching ventures, and given rise to a small, commercial pond-based culture industry 

in Vietnam. Technology developments in nursery systems are likely to provide opportunities for culture 

enterprises in a broader range of environments than is now possible. A major research thrust in the Philippines 

towards developing cooperative sea-ranching enterprises has demonstrated good potential, and institutional/ 

legislative arrangements to ensure adequate property rights have been tested. Rotational culture with shrimp 

is proving successful in Vietnam, while the possibility of proximate co-culture of sandfish and shrimp has 

largely been ruled out. Small-scale experiments in the Philippines raise the possibility of co-culture in ponds 

with a number of finfish species. Current research directions are looking at diversifying technology to increase 

success in a range of coastal conditions, better understanding the social and biophysical conditions required 

for success, and finding ways of effectively scaling-out developed systems and technology. 

Introduction 

Globally, the husbandry of tropical sea cucumbers 

appears ‘on the cusp’ of success—we are starting to see 

the construction of commercial-scale hatcheries and 

farms and, at the other end of the spectrum, sustained 

1 WorldFish Center, Penang, Malaysia 


2 Research Institute for Aquaculture No. 3, Nha Trang, 

Khanh Hoa province, Vietnam 

3 Marine Science Institute, University of the Philippines, 

Diliman, Quezon City, Philippines 

4 University of Stirling, Scotland, United Kingdom 

5 Aquaculture Department, South East Asian Fisheries 

Development Center, Iloilo, Philippines 

22 

forays into community-based culture and sea-ranching 

systems (e.g. see papers in these proceedings). 

However, most have yet to demonstrate commercial 

viability, and many stakeholders are interested to see 

the outcomes of current pilot ventures. This situation 

is a product of both the considerable advances that 

have occurred over the past decade in hatchery and 

grow-out technology, and the resistance of bottlenecks 

to unconstrained success. The widespread and growing 

interest in this commodity is indicative of strong 

market-based drivers to increase production of sea 

cucumber (Brown et al. 2010). This has a dual impact 

of increasing pressure on wild stocks already in crisis, 

yet also opening the door to opportunities for new 

coastal livelihoods based on sustainable approaches to

culture and sea ranching. This symposium is therefore 

very timely, and allows researchers to take stock of current 

benchmarks for various stages of production, and 

gain a shared understanding of bottlenecks, constraints 

and critical areas for further research. 

As the historical global centre of tropical sea 

cucumber harvest (e.g. Gamboa et al. 2004; 

Schwerdtner Máñez and Ferse 2010), countries 

throughout South-East Asia retain a keen interest 

in developments in culture and sustainable resource 

management, and, in many instances, sit at the forefront 

of industry and technology development. The 

precipitous decline in sea cucumber stocks throughout 

the region (Conand 2004; Bell et al. 2008) has had 

dire implications for coastal livelihoods in some areas. 

While not well documented (but see Shiell and Knott 

2010; Wolkenhauer et al. 2010), it is likely that the 

wholesale removal of sea cucumbers has contributed 

to reduced resilience among coastal ecosystems. 

Social impacts of this decline go beyond lost 

income. Traditionally, a significant part of the sea 

cucumber resource in South-east Asia has been 

obtained by ‘gleaning’ in the shallows (Choo 2008). 

Such fisheries provide a disproportionate social 

benefit, as they have no capital entry requirements 

(i.e. they are accessible to those without the means 

to invest) and are accessible to women and children. 

These highly vulnerable shallow resources are 

invariably, however, the first to disappear under 

conditions of uncontrolled harvesting. Harvesting 

deeper resources becomes more capital intensive 

(requiring a boat and diving gear) and is generally 

the exclusive domain of men. A more insidious effect 

of overharvesting is seen as sustained pressure drives 

fishers deeper in search of viable stocks; divingrelated 

accidents leading to permanent disability or 

even death are all too common in villages where sea 

cucumber harvesting plays an important role in livelihoods. 

Clearly, the restoration of livelihoods based 

on near-shore sea cucumber harvest and improved 

governance of the resource have great potential to 

benefit coastal communities throughout the region. 

In addition to sea ranching or enhancing/restocking 

wild stocks, sea cucumber culture can play a critical 

role in restoring resilient livelihoods among coastal 

aquaculture farmers. Shrimp production dominates 

this sector in much of South-East Asia. The diseaserelated 

serial boom-and-bust cycle that has characterised 

shrimp production globally (Dierberg and 

Kiattisimkul 1996) is strongly evident in this region. 

Such cycles leave casualties, and prominent among 

23 

them are small-scale producers who typically have 

limited reserve capital and struggle to recover from 

losing entire crops to disease (Mills et al. 2011). Sea 

cucumbers show substantial promise as a sustainable 

alternative species that can be grown instead of, or 

with, shrimp, and should provide a more tenable risk 

profile. Currently, up to 12 farmers are involved in 

sandfish pond farming in Vietnam. 

Recent developments in sea ranching and pond 

farming in the South-East Asian region are explored 

here, concentrating on Holothuria scabra (sandfish), 

as this is the focus of current development efforts. 

The paper does not seek to provide a comprehensive 

review of all activities in the region, but rather is a 

‘selective highlights’ package that may be somewhat 

biased towards the lead author’s experience. It is 

intentionally biased towards research that does not 

appear elsewhere in this volume; much of the current 

research being undertaken in the region is covered in 

some depth by others in this symposium. The paper 

is organised by ontogenic staging rather than geography, 

considering hatchery, nursery, growing-out and 

postharvest issues separately. 

Hatchery and nursery production 

Simplified hatchery systems 

The earliest reports of hatchery research on sea 

cucumbers date back as far as the 1930s (see Yellow 

Seas Fisheries Research Institute 1991). Today, the 

culture of temperate species (notably Apostichopus 

japonicus) is in full-swing in China and Japan (Chen 

2004), but commercial-scale hatchery production of 

tropical species is only now becoming a possibility. 

Considerable research effort in India (James et al. 

1994) and the Pacific region (Battaglene et al. 1999) 

laid the foundations for culture of H. scabra on a 

commercial scale. These techniques were further 

refined through the work of the WorldFish Center and 

partners in New Caledonia, and published in a comprehensive 

hatchery manual for H. scabra (Agudo 

2006). Recent advances have seen these techniques 

further refined, simplified and customised for lowinvestment 

systems suitable for developing countries 

(Duy 2010, 2012; Gamboa et al. 2012). Among key 

modifications and simplifications that have improved 

success rates are: 

• a reduction in requirements for live feed production, 

to a point where a single species (Chaetoceros 

muelleri) can be used

• low-density culture of larvae (around 0.3 larvae/mL) 

• the use of settlement plates coated with a dried 

algal (Spirulina) paste rather than previous 

techniques of natural conditioning of plates with 

benthic diatoms. 

These techniques reduce the complexity of culture 

systems and the incidence of infestations by parasites 

or copepods, and have led to substantially increased 

survival rates. Experience from Vietnam and the 

Philippines suggests that a current ‘benchmark’ for 

survival from egg to 5-mm juveniles is around 2.5%. 

Experience from the increasing number of pilot-scale 

hatcheries developed in various locations indicates 

that, almost invariably, ‘off-the-shelf’ hatchery systems 

will not be adequate, and a degree of customising 

is required (e.g. Gamboa et al. 2012) to achieve 

acceptable production. 

A ‘state-of-the-art’ hatchery system has recently 

been constructed at the Southeast Asian Fisheries 

Development Center – Aquaculture Department a 

(SEAFDEC–AQD) in the Philippines (Figure 1), and 

several training courses on hatchery techniques have 

now been conducted. The facility is set to play an 

important role in further training and the provision of 

juveniles for further sea-ranching and pond-culture 

trials in the Philippines. 

Nursery systems 

Typically, some 35 days after settling, at a length 

of around 5 mm, sandfish juveniles are moved 

from settlement tanks to a nursery system. While 

hatchery-based raceway systems have proven successful 

at an experimental scale, it is difficult to see 

how such systems could be workable at a commercial 

scale—the costs of the tank area and the water supply 

required are high. A range of nursery systems has 

been trialled in Vietnam and the Philippines under 

Australian Centre for International and Agricultural 

Research (ACIAR) and national funding. Fine-mesh 

nets (referred to as ‘hapas’) are now routinely used 

(Pitt and Duy 2004) and have been extremely successful 

in ponds in Vietnam (Figure 2, left), resulting 

in high survival and growth rates. Juvenile sandfish 

in hapas feed on algal fouling that grows on the hapa 

mesh. In the Philippines it has proven difficult to 

find ponds with adequate seawater exchange rates to 

maintain the salinities required for nursery stages. In 

a Funding provided by ACIAR and Japan International 

Research Center for Agricultural Sciences (JIRCAS), 

and designed in collaboration with RIA3 

24 

response, effort has been directed at developing floating 

hapa systems that can be deployed in sheltered 

marine embayments (Figure 2, right). These systems 

have great potential for community sea-ranching 

operations—they allow the transport of juveniles 

from hatcheries at an early stage, resulting in low 

mortality; and engage communities in the production 

cycle at the earliest opportunity, maximising potential 

financial benefits (Juinio-Meñez et al. 2012a). 

Hapa-based nursery systems are commonly used 

until juveniles reach a weight of 2–5 g. In previous 

pilot trials of both sea ranching (Juinio-Meñez et al. 

2012a) and pond culture (e.g. Pitt and Duy 2004), 

and in commercial culture in Vietnam until recently, 

juveniles have been released to their grow-out environment 

at this size. An ‘advanced nursery’ stage 

has now been introduced in Vietnam. Ponds with an 

optimal seawater supply and muddy-sand, organically 

rich sediment are seeded with 2–5-g juveniles from 

hapas at a high density of up to 50,000 juveniles/ha 

(compared with 10,000 juveniles/ha for grow-out). 

These are grown to up to 50 g and farmers have 

the choice of purchasing either small juveniles or 

advanced juveniles for around twice the price. There 

are two major drivers behind the development of this 

system. First, the typical grow-out time from a 2–5-g 

juvenile to a 350–400-g saleable product in central 

Vietnam is around 12 months. However, in many 

ponds there remains some risk associated with growing 

sandfish through the wet season—pond stratification 

and low salinities may cause reduced growth 

rates or mortalities if not well handled (see ‘Pond 

culture’ below). By seeding ponds with advanced 

juveniles, the grow-out period can be reduced to 

7–9 months, so that the wet season can be avoided. 

Second, the survival rate of larger juveniles is invariably 

greater following release (Purcell and Simutoga 

2008), partially offsetting the additional cost of larger 

juveniles. This advanced nursery system allows for 

the ponds with the best seawater supply to be used 

productively for advanced nursery culture throughout 

the wet season, with a larger number of lower quality 

ponds used for grow-out in the dry season. 

Pond culture 

Grow-out 

Pond culture of sandfish is an attractive proposition 

for several reasons. The high but often transient 

profitability of shrimp culture, combined with the

Figure 1. Purpose-built sea cucumber hatchery at the Southeast Asian Fisheries Development Center – Aquaculture 

Department, Iloilo, the Philippines (Photos: J. Zarate) 

Figure 2. Nursery hapas in a pond at the Research Institute for Aquaculture No. 3 National Seed Production Center, 

Vietnam (left); and floating hapas in an enclosed marine embayment established by the University of 

the Philippines Marine Science Institute (right) (Photos: D. Mills (left) and C. Hair (right)) 

extreme risk profile associated with this activity, 

have resulted in a situation where smallholders have 

tended to lose out to large corporate interests with 

the financial backing to recover from stock crashes. 

Intensification of culture methods has also led to 

severe fouling in ponds, resulting in anoxic sediments 

and the ultimate abandonment of ponds. Sea cucumbers 

potentially represent a lower-risk investment for 

smallholders. As a species that is low on the food 

chain, they provide better environmental outcomes 

than shrimp farming, and do not require feeding if 

stocked in ponds previously used for shrimp culture. 

25 

There are, however, biophysical issues that 

ultimately restrict the number of shrimp ponds 

suitable for sandfish culture. Most critically, the 

vast majority of ponds were established for growing 

Penaeus monodon (tiger shrimp); to maximise 

yield of this species, brackish water is required. As 

a result, ponds were generally located with good 

access to a freshwater source, and it may be difficult 

to maintain the salinities required to optimise sea 

cucumber growth. Holothuria scabra, while somewhat 

tolerant of reduced salinity (Pitt et al. 2001; 

Mills et al. 2008), grows best in marine conditions

(30–34 ppt as a general rule). In many culture trials, 

sudden salinity drops due to storm action and tropical 

downpours have resulted in high mortality (Pitt et al. 

2001; Lavitra et al. 2009; and personal experience 

of two of the authors—N. Duy, Vietnam; C. Raison, 

Thailand). Notably, these issues have largely been 

circumvented in Vietnam, where several farmers 

are producing H. scabra in commercial quantities. 

Mills et al. (2008) assessed survival and growth of 

sandfish through the wet season by direct monitoring 

of commercial ponds and through farmer interviews. 

Although growth rates declined rapidly, survival of 

sandfish enclosed in nine pens within three operating 

commercial ponds was 100% through the 2007–08 

wet season, which included nine consecutive days of 

exceptionally heavy rains. Interviews with farmers 

revealed that, while most lost sandfish due to freshwater 

ingress during their first year of production, 

simple management protocols such as ensuring 

regular tidal water changes or, in some instances, 

using paddlewheels to ‘de-stratify’ b pond water 

resulted in very high survival rates. It should be 

noted, however, that ponds used for sandfish culture 

in central Vietnam have very good canal systems, and 

tidal regimes mean that substantial water changes are 

possible on most tides. Ponds with similar characteristics 

have proven difficult to find in other countries. 

Without a doubt, one of the greatest restrictions on 

profitable pond-based sea cucumber culture is density 

limitation of growth rates. Past research (Battaglene 

et al. 1999) suggests that growth rates decline when 

densities exceed 225 g/m 2, while empirical evidence 

from Vietnam suggests that a density of around 

1 animal/m 2 in coastal ponds (without adding feed) 

provides an optimal balance between growth rates 

and total production for a target harvest size of 

300–400 g (Pitt and Duy 2004). 

Recent experiments at the Shrimp Genetic 

Improvement Center in Thailand (C.M. Raison, 

unpublished data) looked at the relationship 

between stocking density, feed rates, growth and 

survival. An orthogonal experiment compared 

growth and survival over 36 days among treatments 

b Stratification occurs when low salinity water sits on top 

of higher salinity water in the ponds, isolating the higher 

salinity water from the atmosphere. This may lead to 

reduced oxygen levels in the saline water, and a so-called 

‘lens effect’ caused by the upper layer of less saline 

water. This is said to result in increased temperature in 

the saline water, which further increases oxygen demand 

and compounds depletion. 

26 

comprising two densities of early juvenile sandfish 

(average individual weight 1.74 g at densities 

of about 50 and 85 g/m 2), and five feeding rates 

(0.05–0.25 g/treatment/day of commercial shrimp 

starter feed). Preliminary results indicate a strong 

positive relationship between feed rate and growth 

rate, and a weaker negative relationship between 

stocking density and growth rate. While by far the 

highest growth rates were seen among animals held 

at low density with high feed rates (average 234% 

weight gain per individual, compared with 39% for 

high density, low feed rate), the greatest overall gain 

in biomass was seen in the treatment with high density 

of sandfish and moderately high feeding rate. It 

was also clear from results that overfeeding can be an 

issue—survival was reduced at the highest feed rates. 

Where ponds already have rich organic sediments, 

the addition of feed may cause higher mortality rates. 

In addition, where nutrient conditions indicate that 

higher production rates might be achieved through 

feeding, these need to be offset against additional 

labour and feed costs. Results also show that organic 

loading in sediments can be too high for sandfish 

survival, so there is a limit to the effectiveness of 

sandfish for bioremediation in these situations. 

Co-culture: Pond-based co-culture systems involving 

sea cucumbers are conceptually very attractive. A 

pond containing only sea cucumbers for the duration 

of a grow-out cycle ‘wastes’ the space available in the 

water column, while the pond sediment bioremediation 

potential of sandfish has the potential to improve 

pond conditions for co-cultured species. Similarly, 

sea cucumbers grown under sea farms are seen as 

having the potential to alleviate fouling problems, 

while enriched deposits from faeces and food waste 

may increase the growth rates of sea cucumbers 

(Slater et al. 2009). Unsurprisingly, interest in coculture 

in ponds has centered on shrimp, as most 

coastal ponds have been constructed for shrimp 

culture, and shrimp are a high-value commodity. 

Unfortunately, this match gives way on the reality of 

agonistic interactions, and sea cucumbers invariably 

come off second best. Trials with Penaeus monodon 

(tiger shrimp; Pitt et al. 2004) and Litopenaeus stylirostris 

(Pacific blue shrimp; Purcell et al. 2006; Bell 

et al. 2007) showed some initial promise; however, 

larger scale trials proved unsuccessful. 

Recent trials in Vietnam by Mills and Duy 

(unpublished data) on Litopenaeus vannamei (white 

leg shrimp) perhaps ended the shrimp proximate coculture 

ideal. This trial was set up under parameters

that should have greatly favoured sea cucumbers. 

In previous trials, postsettlement juvenile sandfish 

were tested with shrimp post-larvae. In the recent 

trials in Vietnam, larger juveniles (approx. 50 g) 

from ‘advanced nursery’ systems were tested with 

shrimp post-larvae, giving the sandfish a ‘head 

start’. This system would have the advantage that 

both shrimp and sandfish would reach market size 

at around the same time, simplifying the harvest 

process. Small-scale tank trials again showed some 

promise—if shrimp were stocked at fairly low density 

(15 post-larvae/m 2), survival and growth of sandfish 

were acceptable (although lower than controls). 

Interestingly, survival of shrimp was higher in all 

treatments with sandfish than in the shrimp-only 

controls. These trials were scaled up in 15 × 500 m 2 

ponds. The primary objective of the trial was to compare 

productivity and financial return from co-culture 

systems with that of rotational culture systems. The 

results were clear-cut—while growth rates were 

initially fastest in the co-culture treatments, after 6 

weeks in ponds the shrimp had reached a size where 

they could prey on the sandfish, and total mortality 

of sandfish in co-culture ponds followed shortly 

thereafter. It seems that either temporal or physical 

separation of shrimp and sea cucumbers is required 

for successful production of both species in a single 

pond. The former (rotational culture) is already practised 

by a number of producers in Vietnam, and our 

trials have shown high sandfish growth rates in ponds 

recently used for shrimp culture (Mills and Duy, 

unpublished data). Physical separation of shrimp and 

sandfish grown at the same time in ponds has yet to 

receive attention. This is a potentially fertile area for 

research that has yet to be tackled at any level. 

Average growth rate (g/day) 

0.25 

0.20 

0.15 

0.10 

0.05 

0 

27 

Co-culture with finfish is also a possibility. 

Farmers in Vietnam have successfully grown sandfish 

with sea bass (Lates calcarifer or barramundi); 

however, the market for this species in Vietnam is not 

strong, and this combination has not persisted in the 

industry. Recent trials at the SEAFDEC–AQD in the 

Philippines have highlighted several finfish species 

that may be compatible with sandfish. Species for the 

trials were selected based on commercial importance 

within South-East Asia. Species selected were milkfish 

(Chanos chanos), sea bass (Lates calcarifer), 

rabbitfish (Siganus guttatus), grouper (Epinephelus 

coioides), pompano (Trachinotus blochii) and 

mangrove red snapper (Lutjanus argentimaculatus). 

Initial trials involved tank-testing the compatibility 

of juvenile fish with juvenile sea cucumbers. Results 

were most positive for pompano, milkfish and sea 

bass—in all cases survival was close to 100%, 

although the growth rate of the sandfish was notably 

low (Figure 3). Rabbitfish and grouper were not 

compatible with sandfish. Current activities see trials 

with these more successful species being scaled up in 

experimental pond environments. 

Sea ranching 

Sea ranching is essentially a ‘put and take’ activity, 

where cultured juveniles are released into an area 

of natural habitat and harvested when they reach a 

commercially optimal size. Compared with pond 

culture, inputs are nominally lower, as the processes 

between release and harvest are largely left to nature. 

The trade-off here is that, as the level of care that can 

be offered to sandfish throughout the growth process 

is reduced, survival will be considerably lower than 

that seen in pond culture. In addition, property rights 

Sandfish Finfish 

w/ pompano w/ sea bass w/ milkfish 

Figure 3. Average growth rates of sandfish and finfish species held in co-culture

issues are less straightforward and the social dimension 

of culture systems becomes as critical as the biophysical 

dimensions. Researchers in the Philippines 

(see Juinio-Meñez et al. 2012b) have been at the 

forefront of developing strategies for community 

engagement and equitable property rights, as well as 

developing, adopting or adapting techniques necessary 

to build viable sea-ranching systems (Figure 

4). Specific challenges for sea-ranching systems 

include minimising poaching, sustaining engagement, 

matching environmental and social requirements, and 

managing severe weather events 

Minimising poaching: The high value of sandfish 

has meant that protecting sea-ranch areas has 

proven difficult. Permanently manned guardhouses 

have been established at pilot sites in the Philippines 

28 

(Figure 4) to overcome this issue. Clearly, this 

represents a considerable investment on the part of 

the group owners. However, sea ranching is being 

promoted as a supplemental income for small-scale 

fishers, and discussions with participants reveal that 

the opportunity cost of being one of several sea-ranch 

owners involved in site guarding is not high. The 

platform becomes a social meeting point, and fishers 

can just as well sit on the platform and mend nets or 

build gear as they could onshore. 

Sustaining engagement: The time from establishing 

a sea ranch to the first fiscal returns in the 

Philippines will likely be at least 12 months and possibly 

closer to 18 months. Once the first batches of 

released sandfish have reached harvest size, regular 

harvests will be possible; however, the lack of any 

Figure 4. Sea ranching in the Philippines: mature animals from the ranch (left), the guardhouse to counteract 

poaching (top right) and the leader of the sea-ranching group illustrating the principles of the ranch design. 

All photos from the Victory sea ranch, northern Luzon, the Philippines (Photos: D. Mills and C. Hair)

eturn on time or money invested during the early 

stages has been an issue. Pressure from participants 

to harvest at smaller sizes needs to be resisted in 

order to optimise returns from the sea ranch. 

Matching environmental and social requirements: 

Both the engagement of strong and respected 

local institutions and the presence of appropriate 

habitat are essential preconditions for successful 

sea-ranching operations. Imposed on this, appropriate 

mechanisms for site governance must be developed. 

In the Philippines we have encountered a lot of enthusiasm 

to engage in sea-ranching activities, but a lot of 

energy and goodwill can be wasted if the appropriate 

conditions are not present. Managing expectations is 

a crucial part of establishing sea-ranching systems. 

Managing severe weather events: Of the countries 

engaged in active research, the Philippines is particularly 

prone to the impact of typhoons and flooding. 

The shallow inshore areas generally used for sea 

ranching are susceptible to physical damage and acute 

salinity drops from these events. In addition to damage 

to ranching infrastructure and possible mortality 

of stock, at a pilot site in the Philippines it appears 

that stripping of rich organic surface layers from the 

sediment resulted in substantial negative growth of 

standing stock (A. Juinio-Meñez, pers. comm.). 

Restocking / stock enhancement 

The biological case for active restocking of overexploited 

sea cucumber populations is a strong one (Bell 

et al. 2008). Due to the low dispersal ability and the 

need to be close to mates for successful reproduction, 

recovery from heavy overfishing will be protracted 

(‘allee effect’), if indeed at all possible (Friedman 

et al. 2011). Restocking provides a plausible route 

back to viable populations where no other may exist. 

The social case is just as strong—the potential for 

well-organised communities to create sustainable, 

supplemental livelihoods through restocking or stock 

enhancement appears promising. A clear risk with this 

approach is that it can be seen as a panacea where no 

other management systems have succeeded. In reality, 

strong and effective governance reform is an essential 

prerequisite for the establishment of effective restocking 

programs. 

A lot of recent research undertaken in the development 

of sea-ranching systems provides essential 

background information on pathways to establishing 

restocking or enhancement programs. This includes 

all work on hatchery and nursery systems, tagging 

methods, transportation systems, release methods 

29 

and monitoring. However, while the research area 

of restocking and enhancement remains one of keen 

interest, the realities to date of legitimate scientific 

investigation that can identify unambiguous impact 

mean that these areas are yet to be tackled. Unlike sea 

ranching, restocking is a ‘whole-of-life-cycle’ process, 

in which reproductive and recruitment dynamics need 

to be understood and accounted for in program design. 

Success requires that enhanced populations occupy 

‘source’ areas where coastal currents carry larvae into 

areas of good habitat for recruitment and growth. If 

the choice of location is poor, larval mortality may be 

too high to provide any detectable enhancement effect. 

Future research 

The authors are aware of active research programs 

in the Philippines (hatchery, nursery systems, sea 

ranching, co-culture, pond culture), Vietnam (hatchery, 

pond culture, co-culture, sea ranching), Thailand 

(pond culture, sea ranching) and Malaysia (hatchery, 

sea ranching). Strong institutional support, as well 

as donor-funded programs in the Philippines and 

Vietnam, in particular, will ensure continued development 

of sea-ranching and pond-culture systems. 

Current research in these countries is focusing on 

technology and system development to diversify 

options for producers, and on further understanding 

the optimal socioeconomic and biophysical preconditions 

for successful enterprises. Models for scaling 

out technology and catalysing uptake by small-scale 

producers are being tested across broad geographic 

regions. The pond-culture industry in Vietnam is 

currently growing ‘organically’, with around a dozen 

farmers involved. This provides good opportunities 

for future research in partnership with industry. In the 

Philippines, a major focus in the near future will be 

capacity building among local institutions to support 

early entrants into the sea-ranching industry. The 

establishment of model enterprises is expected to 

provide a strong basis for technology uptake. 


Research in Vietnam has been supported by ACIAR, 

the WorldFish Center and the Government of Vietnam. 

Research in the Philippines has been supported by a 

multistakeholder government program and ACIAR. 

The research reported from Thailand was funded by 

the Thailand Research Fund and the UK Department 

for Innovation, Universities and Skills.

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Sea cucumber hatchery production 

Egg release from a female Holothuria scabra during spawning induction in a 

hatchery (Photo: Cathy Hair) 

33

Large-scale sandfish production from 

pond culture in Vietnam 

Nguyen D.Q. Duy 1 

Abstract 

In recent years the farming of sandfish (Holothuria scabra) has been adopted by a number of farmers in 

south-central Vietnam. Hundreds of thousands of hatchery-produced juvenile sandfish have been stocked into 

ponds in the region. Broodstock were collected from the wild in Khanh Hoa province and from commercial 

culture ponds at 40–500 g weight. The broodstock were stored in a holding pond at a low density without 

adding feed. Animals of average weight (~350 g) were then transferred to conditioning tanks about 1 month 

prior to spawning. Indoor conditioning tanks were prepared with a sandy substrate and sand-filtered water 

supply. The animals were fed with fine shrimp feed. Simplified hatchery methods using cheap and basic 

equipment have been refined over the past decade, and consistent batches of juveniles can now be produced 

at will, with around 50,000 competent juveniles produced from batches of 2 million eggs. 

Sandfish were cultivated in ponds with muddy-sand or coral-sand substrates using simplified techniques 

and locally developed management methods. The results of model sandfish culture ponds in three provinces 

proved that these methods can be profitable for farmers in these coastal areas. The constraints to commercial 

sandfish pond culture in Vietnam are no longer pond management or the price paid by the dealers, but density 

limits and culture duration. 

Introduction 

High demand for sea cucumber (e.g. sandfish 

(Holothuria scabra)) in China has resulted in overfishing 

in many countries in the Asia–Pacific region 

(Lovatelli et al. 2004). While restocking offers a 

plausible fast-track recovery of sandfish fisheries 

(Bell et al. 2007), pond culture provides livelihood 

options and a source of income for coastal communities 

engaged with faltering shrimp-farming 

enterprises (Mills et al. 2008). 

Hatchery and juvenile production techniques have 

been developed, documented and carried out with a 

minimum of advanced infrastructure (Battaglene 

1999; Pitt and Duy 2004; Duy 2005, 2010; Agudo 

2006). Over the past decade, many studies on breeding 

and rearing sandfish have been conducted by 

1 Research Institute for Aquaculture No. 3, Nha Trang, 

Khanh Hoa province, Vietnam 


34 

the Vietnamese Research Institute for Aquaculture 

No. 3 (RIA3) sandfish hatchery in Van Ninh district, 

Khanh Hoa province, and the WorldFish Center 

(WorldFish). Other sandfish projects in Vietnam 

have been supported by the Australian Centre for 

International Agricultural Research (ACIAR), the 

Danish International Development Agency, the 

Vietnamese Government, the South East Asian 

Fisheries Development Center (SEAFDEC) and so 

on. The hatchery and juvenile production techniques 

developed to date have been disseminated to the 

project partners and other private sector operators in 

the Asia–Pacific region. 

The large-scale production of sandfish for pond 

culture has been conducted in Vietnam based on 

knowledge developed from research collaborations 

between RIA3 and ACIAR–WorldFish (Pitt and 

Duy 2004; Bell et al. 2007; Mills et al. 2008). This 

paper describes the simplified techniques used in 

this research for seed production of sandfish and 

large-scale sandfish production for pond culture in

Vietnam. The progress of research on seed production 

and grow-out of sandfish will support the industry’s 

expansion in Vietnam and elsewhere in the region. 

Simplified techniques for seed 

production of sandfish 

Sandfish broodstock management 

A few years ago, sandfish broodstock were collected 

from the wild or holding ponds and pens, and immediately 

induced to spawn. Various methods of spawning 

stimulation were trialled but proved unreliable. 

In recent years, however, the broodstock have been 

conditioned in tanks in the hatchery for a period of 

about 1 month to allow gonads to reach full maturity. 

In the simplified techniques, concrete or fibreglass 

tanks placed indoors for shade were prepared with a 

10–15-cm layer of cleaned dried sand, and supplied 

with sand-filtered sea water to a depth of 0.5 m. 

Adult sandfish weighing more than 350 g were 

transferred from holding ponds to conditioning tanks. 

The seawater temperature in the conditioning tanks 

was stable, maintained below 30 °C. The density of 

broodstock should be less than 2 animals/m 2. Water 

exchange was carried out in the morning to avoid 

broodstock being induced to spawn from thermal 

shock. Fine shrimp starter feed at 1 g/m 3 was fed 

twice a day. In addition, broodstock were co-cultured 

with the carnivorous Babylon snail (Babylonia 

areolata), providing extra protein-rich feed that contributed 

to sandfish growth and condition. Even when 

kept in good health, broodstock might lose weight 

in 1 month of conditioning; weight loss of less than 

20% is acceptable. 

After conditioning in tanks, broodstock were 

reliably induced to spawn, being more sensitive to 

thermal shock stimulation (Agudo 2006; Duy 2010). 

This allowed the year-round production of sandfish 

juveniles. Pond-held broodstock are maintained close 

to the hatchery for convenience of transfer to conditioning 

tanks. There should be sufficient animals in 

holding ponds to substitute a group of 50 animals 

after each breeding cycle in the hatchery. 

Larval rearing 

Optimal larval density and feed were the two 

main factors in maximising growth and survival. The 

micro-algae Chaetoceros muelleri was used for the 

swimming and settled stages in the hatchery. Using 

a single species of algae represented a significant 

35 

simplification of the technical and infrastructure 

requirements for larval production, and meant that 

techniques could be more easily adopted by smallscale 

hatcheries such as former shrimp hatcheries. 

The feeding rate was increased gradually during 

larval rearing. The optimal rearing density was at 

200–300 larvae/L. At high densities of larval rearing, 

growth rates can decrease and high malformation 

rates are observed. As a result, it is better to get 10% 

survival (to 2–5-mm juveniles) from a starting point 

of 200 larvae/L in 4 weeks than 1% survival from 

1,000 larvae/L in 6 weeks. In addition, faster growth 

of juveniles can prevent predator disasters, such as 

copepod infestation. Loss from copepods was also 

minimised by preparing settlement plates by coating 

them in a slurry made from Spirulina paste (Figure 1) 

rather than natural conditioning through immersion 

in sea water (Duy 2010). 

Juvenile production 

Simplified hatchery methods using cheap and 

basic equipment were refined, and consistent batches 

of juveniles can now be produced at will, with around 

50,000 competent juveniles produced from batches 

of 2 million eggs. Hapa nets were used effectively 

for a low-cost nursery in ponds (Figure 2), removing 

the need for large raceways at hatchery facilities for 

juvenile rearing. 

Testing economic return from 

large-scale production in model 

ponds 

Design of model ponds 

We used two ponds in each of three provinces 

(Khanh Hoa, Phu Yen and Ninh Thuan) in central 

Vietnam. The ponds had a coral-sand or muddy-sand 

substrate. The ponds in Phu Yen and Ninh Thuan were 

used previously to rear shrimp and swimming crab. 

There was a collaborating agreement between RIA3 

and farmers to operate model ponds in Phu Yen and 

Ninh Thuan provinces. The two ponds in Khanh 

Hoa province were sediment settlement ponds at the 

National Center for Seed Production, belonging to 

RIA3, and were operated by project staff. 

Pond preparation 

All chosen ponds were located in the intertidal 

zone for convenient seawater exchange. The steps of 

pond preparation were as follows:

Figure 1. Preparation of Spirulina-coated settlement plates 

Figure 2. Hapa nets used for a first-stage nursery of sandfish in ponds 

36

• Dry the pond by draining through sluice-gates and 

pumping. 

• Remove predators and unwanted seaweed. 

• Till the sediment to disturb and wash the mud 

layer, ensuring that there is a burying layer of 

about 5 cm. 

• Build a net pen at the sluice-gates to exclude 

predators, and prevent escape or massing of sandfish 

in this area. 

• Apply lime (agriculture or hydrated) at 0.5–1.0 t/ha. 

• Fill the pond with sea water 1 week prior to stocking 

with juvenile sandfish. 

Transportation of juveniles 

The 2–20-g juveniles were produced at the RIA3 

sandfish hatchery from a single spawning in May 

2008. They were nursed to a size of 2 g in ponds 

using the hapa systems described by Pitt and Duy 

(2004), and then grown at high density in earthen 

ponds to a larger size (advanced nursery) before 

stocking in the model ponds in Phu Yen and Ninh 

Thuan. They were selected and placed in bare tanks 

to defecate for 1–2 days prior to transferring them 

to the ponds. An open transportation method of 

juveniles in foam boxes was used effectively, with 

survival rates of up to 100%. 

Water quality management 

The biggest causes of sandfish mortality in ponds 

are known to be predators and the stratification of 

pond water in the wet season. Despite this, we did 

not use paddle wheels to reduce stratification in 

the six model ponds; it was found to be unnecessary 

due to the efficiency of mixing during tidal 

water changes and wind mixing. During culture, 

pond water depths were kept at 0.8–1.5 m, and 

the water was changed by opening and closing the 

sluice-gates. Water quality parameters (temperature, 

37 

salinity) were monitored daily (Table 1). We found 

that the two model ponds in Khanh Hoa province 

experienced less water exchange than other ponds, 

which we believe was due to neap tides and hot 

weather. This resulted in high temperatures (up to 

36 °C) and salinities (up to 41‰) in these two ponds 

in the dry season. Ponds in Ninh Thuan and Phu Yen 

provinces had daily water changes, resulting in better 

conditions. 

Harvest 

We found that sandfish in all ponds reached commercial 

size (>300 g) in average weight in November 

2009, after 9–14 months in ponds (Table 2). The 

harvest was brought forward due to a significant 

flood event. Ponds in Khanh Hoa had endured the last 

wet season in 2008 without any losses. Final yields 

were in the range 2.61–2.80 t/ha (Table 2). Survival 

rates were higher for juveniles stocked at larger 

sizes (80%, 85% and 87% for 2-g, 10-g and 20-g 

juveniles, respectively). The sandfish were sold to 

local dealers and buyers in Ho Chi Minh City. Most 

of the production of this harvest was processed by a 

Singaporean processor using his preferred techniques 

to ensure higher quality. Local buyers also bought 

some sandfish and degutted them at the pond, then 

processed them using traditional methods. The dried, 

cultured sandfish were later seen at the market in Ho 

Chi Minh City, Vietnam. 

Financial return from pond culture 

At the harvest in November 2009, cultured sandfish 

were sold to processors at the ponds (Figure 

3) for 35–40,000 Vietnamese dong (VND)/kg 

(US$2.00–2.20) whole wet weight. The profit fluctuated 

between 49.5% and 80.1%, and the profit margin 

was estimated at 33.1–45%. This is equivalent to 

about 30–40 million VND (US$1,700–2,200)/ha/crop. 

Table 1. Mean (± SD) temperatures and salinities in model ponds in Khanh 

Hoa (KH), Phu Yen (PY) and Ninh Thuan (NT) provinces 

Pond Temperature (°C) Salinity (‰) 

KH1 27.4 ± 4.8 24.5 ± 8.5 

KH2 27.4 ± 5.0 24.5 ± 8.4 

PY1 28.2 ± 2.8 25.6 ± 6.5 

PY2 28.2 ± 2.7 25.6 ± 6.6 

NT1 29.5 ± 3.4 30.0 ± 2.7 

NT2 29.5 ± 3.4 30.1 ± 2.7

Table 2. Results of sandfish model pond culture in three provinces, 2008–09 

Province Total area 

(m 2) 

Discussion 

Mean 

stocking 

size (g) 

Density 

(juv./m 2) 

The results from model ponds in Phu Yen, Khanh 

Hoa and Ninh Thuan provinces showed that monoculture 

of sandfish in ponds can be profitable to 

farmers in coastal areas. It was clear that the bigger 

the sandfish are when released, the higher the survival 

rates obtained. However, there was a slower growth 

rate at around 1.0 g/day in these ponds compared 

with sandfish growth rates previously reported from 

other pond studies. In Van Ninh, Khanh Hoa province, 

growth rates were 1–3 g/day or 1.0–1.8 g/day, 

38 

Mean 

weight at 

harvest (g) 

Mean 

survival 

rate (%) 

Duration 

(days) 

Yield 

(t/ha) 

Khanh Hoa 14,000 2 1 350 80 420 2.80 

Phu Yen 10,000 10 1 310 85 305 2.63 

Ninh Thuan 10,000 20 1 300 87 274 2.61 

Figure 3. Processing of pond-cultured sandfish at Research Institute for Aquaculture No. 3 

respectively (Pitt and Duy 2004; Mills et al. 2008). 

In the hatchery, density affects sandfish growth at 

biomass levels greater than 225 g/m 2 (Battaglene 

et al. 1999). There may have been limited natural 

food and benthic organic matter in the substrates, 

thus affecting the growth in our model ponds when 

this threshold density was exceeded due to high 

survival rates. This led to a long culture period to 

attain commercial size for sandfish in the model 

ponds in Khanh Hoa province, while sandfish in the 

ponds in the two other provinces were at commercial 

size because of the bigger size of release. In fact, the

growth of sandfish appears to depend on many factors 

including substrate, pond site and supply of natural 

feed through water exchange. 

During culture, water management in the sandfish 

ponds requires attention by the farmers. Mass mortalities 

are likely if ponds are not adequately attended 

in the wet season; this has resulted in high mortality 

rates in the past. All the evidence gathered so far suggests 

that these problems can be cheaply and effectively 

overcome, even in uncharacteristically heavy 

and prolonged periods of rain (Mills et al. 2008). 

However, the relatively long duration of culture 

increases the expense of renting ponds and labour 

costs due to the high risk over the wet season. The 

prices paid for sandfish are increasing over the years, 

which will support a higher profit for the farmers in 

the future. 

The results of the model pond trials have been 

encouraging for industry expansion in the region and 

sandfish farming is contributing to viable livelihoods 

for the farmers in coastal central Vietnam. 

References 





Battaglene S.C. 1999. Culture of tropical sea cucumbers for 

stock restoration and enhancement. Naga –The ICLARM 

Quarterly 22(4), 4–11. 

39 


Survival and growth of cultured juvenile sea cucumber, 


Bell J.D., Agudo N.S., Purcell S.W., Blazer P.M., Pham 

D. and Della Patrona L. 2007. Grow-out of sandfish 

Holothuria scabra in ponds shows that co-culture with 

shrimp Litopanaeus stylirostris is not viable. Aquaculture 

273, 509–519. 

Duy N.D.Q. 2005. Improving the seed production technique 

of sandfish Holothuria scabra in Nha Trang, Khanh 

Hoa. Research Institute for Aquaculture No. 3, FSPS 

Programme. SUMA Project Final Report. 


scabra) in Vietnam. Aquaculture Extension Manual No. 

48, Southeast Asian Fisheries Development Center, 

Iloilo, Philippines. 

Lovatelli A., Conand C., Purcell S., Uthicke S., Hamel J-F. 

and Mercier A. (eds) 2004. Advances in sea cucumber 

aquaculture and management. FAO Fisheries Technical 

Paper No. 463. Food and Agriculture Organization of the 


Mills D., Duy N.D.Q. and Johnson W. 2008. Review of sandfish 

pond-culture progress in Vietnam. ACIAR Project 

no. FIS/2007/117, Final Project Report. 

Pitt R. and Duy N.D.Q. 2004. Breeding and rearing of sea 

cucumber Holothuria scabra in Vietnam. In ‘Advances 

in sea cucumber aquaculture and management’, ed. 

by A. Lovatelli, C. Conand, S. Purcell, S. Uthicke, 

J.-F. Hamel and A. Mercier. FAO Fisheries Technical 

Paper No. 463, 333–346. Food and Agriculture 


In-vitro fertilisation: a simple, efficient 

method for obtaining sea cucumber 

larvae year round 

Igor Eeckhaut 1,2*, Thierry Lavitra 2,3, Aline Léonet 1, 

Michel Jangoux 4 and Richard Rasolofonirina 3 

Abstract 

Obtaining eggs and larvae in large quantities is a critical point for the economic viability of sea cucumber 

aquaculture. In this paper, spawning induction methods and in-vitro fertilisation (IVF) methods are presented 

and compared. The IVF technique developed in Madagascar (MH-IVF) is a simple, cost-efficient method 

that enables hatcheries to obtain clean, fertilised eggs of sea cucumbers year-round. MH-IVF does not 

require high-tech equipment and is applicable in small- and large-scale hatcheries. It ensures the best control 

at the very beginning of the work on the number and type of genitors (i.e. sex, length, weight, colour); the 

quality of the gonads (healthy versus parasitised); and the number, size and quality of spermatozoa and eggs. 

MH-IVF involves the sacrifice of very few genitors compared with the individuals obtained and sacrificed 

for production. Yet, it does not influence genetic drift any more than spawning induction methods. 

Introduction 

It is evident today from many surveys that the world’s 

wild stocks of sea cucumbers are depleting fast, and 

almost everywhere this is due to the high demand 

from the Chinese market. The disappearance of sea 

cucumber wild stocks is not only a problem at the 

ecological level (these organisms being among the 

best bioturbators of the sediments in many marine 

ecosystems), but it is also a huge social problem as the 

sea cucumber trade ensures a livelihood for millions 

of humans in developing countries. One of the best 

answers to this worldwide problem is to develop efficient 

aquaculture systems where coastal villagers of 

1 Laboratoire de Biologie Marine, Université de Mons, 

Mons, Belgique 


2 Madagascar Holothurie S.A., Toliara, Madagascar 

3 Institut Halieutique et des Sciences Marines, Université 

de Toliara, Toliara, Madagascar 

4 Laboratoire de Biologie Marine, Université Libre de 

Bruxelles, Bruxelles, Belgique 

40 

developing countries can be involved in some phases 

of the farming. However, aquaculture is basically a 

business where the end product (i.e. the trepang) is 

sold into the Chinese market. The private companies 

that are involved in this process need benefits: preferably 

quickly and with a minimum of investments. It 

is thus crucial for the sustainability of sea cucumber 

aquaculture that the profitability of each step in the 

process—obtaining eggs, rearing larvae, pre-growing 

juveniles and growing adults—is optimised. Obtaining 

eggs and larvae in large quantities is thus a critical 

point for the economic viability of the industry. 

Over the past 10 years, we have developed a new 

method based on in-vitro fertilisation (IVF) for 

obtaining sea cucumber larvae throughout the year in 

Madagascar. This method is used routinely by the company 

Madagascar Holothurie S.A. (MH.SA), which was 

created at the end of the research phase. We present here 

a description of this method and the various techniques 

that allow aquaculturists to obtain fertilised eggs of sea 

cucumbers. Some are still in the research phase but 

appear to show promise for the near future.

There are basically three types of method: unforced 

spawnings, forced spawnings and IVF. The first 

method is used only on the East Pacific Isostichopus 

fuscus in Ecuador. There, and for that species only, 

spawning occurs monthly depending on the lunar 

cycle. There is no need to force the spawning but just 

to know the right time when genitors spawn (Mercier 

et al. 2007). To develop this method, Mercier et al. 

(2007) monitored several hundred individuals nearly 

every month over 4 years. Isostichopus fuscus displayed 

a lunar spawning periodicity: 0.7–34.9% of 

individuals consistently spawned 1–4 days after the 

new moon. Spawning occurred mostly within one 

evening; however, some gamete release was often 

recorded over two to four consecutive evenings. 

Individuals maintained in captivity for several months 

retained their spawning periodicity and timing with 

the lunar cycle. The percentage of spawning individuals 

was higher and a greater overlap between male and 

female peak spawning activity was observed during 

clear conditions compared with overcast conditions. 

Aside from the I. fuscus case, fertilised eggs are 

obtained by either inducing the spawning of genitors 

or fertilising oocytes that have been extracted 

from gonads. Spawning induction methods are 

based mainly on mechanical stress inflicted on adult 

individuals, but can also be stimulated by chemical 

incubations or injections. 

Spawning induction methods 

In the very first attempt to artificially obtain viable 

gametes from sea cucumbers, a Japanese scientist 

attempted the stripping technique in the 1930s (Inaba 

1937). The rate of fertilisation was only about 20%, 

and many of the larvae were malformed. Therefore, 

this method is no longer used for larval production. 

Today, the efficient mechanical stresses used are 

thermal shocks, and stimulation through drying and 

water pressure. Often a combination of these methods 

is used to force spawning. 

Thermal shocks 

Thermal shocks are the most widespread sea 

cucumber spawning induction technique in aquaculture. 

The method has been successful in Iran 

(Dabbagh et al. 2011), Mauritius (Laxminarayana 

2005), India (James et al. 1994), Maldives (B. Giraspy, 

pers. comm.), the Philippines (R. Gamboa, pers. 

comm.), Vietnam (Pitt and Duy 2004), Australia 

(Morgan 2000a; Ivy and Giraspy 2006), Solomon 

41 

Islands (Battaglene et al. 2002), Fiji (Hair et al. 

2011), New Caledonia (Agudo 2006), Tanzania 

(G. Robinson, pers. comm.), and Japan and China 

(Shuxu and Gongehao 1981; Li 1987). 

Thermal shocks involve placing genitors into 

baths of different temperatures, and the steps of the 

method vary from place to place. In Mauritius, for 

example, Laxminarayana (2005) induced the spawning 

of Bohadschia marmorata and Holothuria atra 

by decreasing the seawater temperature by 3–5 °C by 

the addition of ice. After 5 minutes the sea cucumbers 

were introduced into another tank filled with filtered 

sea water at normal temperature (3–5 °C higher 

than the first tank temperature). For H. scabra, the 

water temperature is raised by 3–5 °C for 1 hour, 

either by adding warmed sea water to the spawning 

tank or using aquarium heaters (Agudo 2006). 

The water temperatures should be kept within the 

range 28–32 °C. If the ambient water temperature is 

>30 °C, it is recommended to give a cold shock treatment 

for 1 hour before the heat shock. Sealed plastic 

bags containing ice are added to the tank to quickly 

lower the water temperature by 5 °C (Agudo 2006). 

Thermal shock is the most commonly used method 

to induce spawning of Apostichopus japonicus 

in Japan and China. Most spawners release eggs 

or sperm when the water temperature is raised by 

3–5 °C above the ambient temperature. The induction 

of spawning by sea cucumbers in Japanese and 

Chinese hatcheries is usually carried out by regulation 

of rearing conditions, such as temperature, water 

exchange and light intensity. In A. japonicus cultivation 

in Japan, wild-caught broodstock are induced 

to spawn in tanks of sea water about 5 °C higher 

than natural sea water and under dark conditions. 

However, this method has some drawbacks in that 

it is sometimes ineffective and the rate of spawning 

is inconsistent. 

Water pressure and drying treatments 

These methods are often used in combination with 

thermal shocks or if thermal shocks were unsuccessful. 

The broodstock are left to dry in a tank in 

the shade for about half an hour before subjecting 

them to a powerful jet of sea water for a few minutes 

(Agudo 2006). The broodstock are then returned to 

the spawning tank at ambient water temperature. 

During the drying treatment the broodstock are left 

in the shade, completely dry, or in a few centimetres 

of sea water, for 30–45 minutes. These methods 

are commonly used with H. scabra as well as

A. japonicus. For the latter species, the operation 

often starts at about 17:00 hours, when the water in 

the temporary stocking tank is drained away and the 

spawners are exposed to air for 30–60 minutes, after 

which they are jetted with water for about 5–10 minutes. 

After about 1.5–2.0 hours, the spawners move 

upwards, become restless and toss their head from 

side to side. The males begin to spawn first, followed 

by the females about half an hour later. 

Chemical incubations and chemical 

injections 

The addition of a food stimulant is sometimes 

used for inducing spawning in sea cucumbers. Dried 

algae (Spirulina at a rate of 30 g per 300–500 L, 

or Algamac 2000 at a concentration of 0.1 g/L) is 

added to the tank containing broodstock for 1 hour 

(Agudo 2006). After 1 hour of incubation, the water 

is removed from the tank and replaced with clean 

water at ambient temperature. 

Mercier and Hamel (2002) demonstrated that 

the transfer of perivisceral coelomic fluid (PCF) 

can be used as a reliable tool to induce spawning 

in mature individuals. PCF collected from holothurians 

that had been in the typical spawning posture 

without shedding gametes for about 20 minutes 

triggered spawning in 71–100% of conspecifics. The 

individuals responded to the injection of a 2–3-mL 

aliquot by displaying the spawning posture within 

30–62 minutes and by massive gamete broadcast. 

The inductive substance was found not to be sexspecific 

since positive responses were observed in 

individuals of the same or opposite sex as the donor. 

The PCF of a spawning donor was also active when 

added to the surrounding sea water, as it induced the 

typical posturing in 47–65% of mature individuals, 

and subsequent gamete release in 20–31% of them 

less than 85 minutes later. 

Although most experiments were performed with 

Bohadschia argus, similar results were obtained with 

B. marmorata, Holothuria leucospilota and H. atra. 

Interspecific trials were also successful, implying 

that the chemical involved is not species-specific. 

Although this method is promising, it is still not 

applied in sea cucumber aquaculture as it relies 

totally on the observation of genitors in spawning 

posture, which is a real challenge in non-natural 

conditions. However, if the bioactive molecule present 

in PCF is identified, this method should have 

a great advantage over the stress-induced methods 

described above. 

42 

Kato et al. (2009) purified one small pentapeptide 

from the buccal tissues of A. japonicus that has a 

practical value to induce spawning in the hatchery setting 

(Fujiwara et al. 2010). Kato et al. (2009) named 

the identified native peptide ‘cubifrin’. Mature A. 

japonicus injected with cubifrin during the reproductive 

season, from February to May, displayed sequential 

reproductive behaviours, which comprised climbing 

the side wall of the tank toward the water surface, 

waving the head and shedding gametes. Gamete 

shedding started about 60 and 80 minutes after the 

injection in males and females, respectively, and was 

completed almost simultaneously in both sexes about 

2 hours after the administration. Repeated injections 

of cubifrin at intervals of about 10 days successfully 

induced multiple spawns in both males and females. 

Induction of spawning by cubifrin in A. japonicus is an 

effective, simple and cost-effective method requiring 

only the injection of cubifrin solution into the body 

cavity. Cubifrin injections, however, were not effective 

in other holothurians, and the possibility of using them 

on other sea cucumber species remains to be examined. 

In-vitro fertilisation 

In-vitro fertilisation is a process by which female 

germinal cells are fertilised by sperm in non-natural 

conditions; that is, outside the female genital tracts in 

organisms with internal fertilisation and in laboratory 

conditions for organisms with external fertilisation. 

The problem with IVF in sea cucumber aquaculture 

is that the development of oocytes (as is the case for 

the female germinal cells of all animals) is stopped 

during the meiosis at prophase I. 

Oocyte maturation naturally concludes in 

sea cucumbers just before or during spawning, 

resulting in mature oocytes ready to be fertilised. 

Consequently, oocytes extracted from ovaries by 

dissection are not ready to be fertilised—they must 

undergo maturation first. In echinoderms the mechanism 

of maturation has been reviewed recently by 

Mercier and Hamel (2009), and is best understood in 

asteroids (sea stars). A gonad-stimulating substance 

(GSS) produced by the radial nerve cord (Kanatani 

1964) acts on the ovarian follicle cells, which, in turn, 

produce a secondary substance, the maturation inducing 

substance (MIS), identified as 1-methyladenine 

(1-MeA) (Kanatani and Shirai 1967; Kanatani 1969). 

The 1-MeA acts on an oocyte membrane receptor to 

activate an intracellular maturation promoting factor 

(MPF) (Stevens 1970; Yamashita et al. 2000), which

induces oocyte maturation involving germinal vesicle 

breakdown (GVBD), chromosome condensation and 

extrusions of the polar bodies. 

This oocyte maturation process is considered 

to be universal, with few variations among species 

(Kishimoto et al. 1982; Yamashita et al. 2000). It is 

also presumed to occur in sea cucumbers, although 

this assertion is untested. Maruyama (1985) demonstrated 

that a GSS existed in five sea cucumber species; 

comprising a peptide of several thousand daltons 

having similar characteristics to the asteroid GSS. 

Smiley (1988) suggested that the MIS of Stichopus 

californicus is likely to be a 2,8 di-substituted adenine. 

It was demonstrated, moreover, that the action 

of 1-MeA can be mimicked in sea stars (Kishimoto 

and Kanatani 1973; Kishimoto et al. 1976) and sea 

cucumbers (Smiley 1990) by various molecules such 

as L-cysteine (Kishimoto and Kanatani 1973), dithiothreitol 

(DTT) (Kishimoto and Kanatani 1980) or 

dimercaptopropanol (DMP) (Kishimoto et al. 1976). 

Yet, the endocrine substances involved in natural sea 

cucumber oocyte maturation remain unknown. 

In sea cucumber aquaculture, two methods of IVF 

have proven to be efficient. The first method is still 

in the research phase and acts in activating ovarian 

cells that themselves induce oocyte maturation during 

the spawning period. This recently discovered method 

involves the incubation of oocytes in a gonadstimulating 

substance-like (GSSL) solution before 

fertilisation (GSSL-IVF) (Katow et al. 2009). The 

second method acts directly on vitellogenic oocytes 

and is efficient both during and outside the spawning 

period (Léonet et al. 2009). This technique has been 

used routinely at the MH.SA hatchery in Madagascar 

for several years and is referred to as MH-IVF. 

GSSL-IVF 

Recently, Katow et al. (2009) isolated a GSSL 

molecule from the radial nerve of the sea cucumber 

A. japonicus (Aj-GSSL), and its partial DNA and 

protein sequences were characterised. The researchers 

incubated tubes of ovaries full of vitellogenic 

oocytes with various extracts during the spawning 

season of the sea cucumber. Radial nerve extract at 

3 mg/mL induced GVBD in 85% of immature ovarian 

oocytes. A synthetic 43-amino acid Aj-GSSL 

generated from this sequence induced GVBD in 

50% of immature ovarian oocytes, and an N-terminal 

21-amino acid peptide of the synthetic partial 

Aj-GSSL (Aj-GSSL-P1) induced GVBD in 80% of 

immature ovarian oocytes. 

43 

MH-IVF 

Léonet et al. (2009) analysed the effects of a 

powerful oocyte maturation inductor (OMI) used routinely 

by MH.SA on oocytes of the commercial species 

Holothuria scabra and on various other species 

of sea cucumbers. The new bioactive molecule was 

isolated from echinoderm extracts and identified by 

mass spectrometry, and the active site of the biomolecule 

was synthesised (international patent number: 

WO 2008/003691; patent title: ‘Oocyte maturation 

method’). The new OMI induces the maturation and 

fertilisation of more than 90% of oocytes, while other 

OMIs described in the literature (i.e. 1-MeA, DTT, 

DMP and L-cysteine) induce between 28–90% of 

oocytes to mature (Figure 1). The use of the other 

OMIs result in fertilisation rates that never exceed 

40% (Figure 1), and the resultant larvae often present 

developmental abnormalities. 

One of the advantages of the new OMI compared 

with the other methods is that it is effective throughout 

the year, even outside the spawning season of sea 

cucumbers. In H. scabra, the difficulty of obtaining 

fertilised eggs throughout the year by conventional 

methods such as thermal shocks varies according 

to the geographic location, seemingly being easier 

when H. scabra populations are closer to the equator. 

The reproductive cycle of H. scabra has been well 

investigated over most of its geographic range—it is 

known in the Southern Hemisphere for populations 

in Indonesia (05°S; Tuwo 1999), Solomon Islands 

(09°S; Ramofafia et al. 2003), New Caledonia (20°S; 

Conand 1981) and Australia (27°S; Morgan 2000b); 

and in the Northern Hemisphere for populations in 

India (09°N; Krishnaswamy and Krishnan 1967) and 

the Philippines (13°N; Ong Che and Gomez 1985). 

The methods used during these studies were different 

but, globally, they strongly suggest that at least a small 

proportion of H. scabra in these populations spawn all 

year round (Hamel et al. 2002). However, the intensity 

of spawning over a year is different from one population 

to another: it can be continuous; it can increase 

once during a period of 2–3 months (i.e. an annual 

reproductive cycle); or it can increase twice with one 

of the two peaks of spawning intensity being higher 

than the other (i.e. a biannual reproductive cycle). 

Figure 2 shows the ovarian maturation in the 

H. scabra population around Toliara (Madagascar) 

(Rasolofonirina et al. 2005). Each bar represents 

30 females whose ovaries have been sectioned and 

characterised into five stages of maturity. The ovaries

Percentage 

100 

80 

60 

40 

20 

0 

a 

Figure 1. Comparison of the efficiency of various substances on the oocyte 

maturation in Holothuria scabra (from Léonet et al. 2009). Oocytes 

have been extracted from the ovaries and incubated with the 

following substances: SW = sea water; DMP = dimercaptopropanol; 

1-MeA = 1-methyladenine; L-cyst = L-cysteine; DTT = dithiothreitol; 

MH ind = inductor used in Madagascar. Incubation time was 2 hours. 

The blue bars indicate the percentage of oocytes that were mature after 

incubation, and the red bars the percentage of oocytes that were fertilised 

after addition of spermatozoa. Small a, b, + and – indicate significant 

similarities or differences: two adjacent signs that are similar (e.g. b and 

b) indicate similarity of the effect. 

of two stages, termed ‘post-spawning’ and ‘resting’, 

are composed mainly of oogonia and oocytes at the 

beginning of the vitellogenesis, and are not ready to 

undergo maturation. The ovaries of the three other 

stages, termed ‘growing’, ‘mature’ and ‘spawning’, 

include mainly oocytes at the end of the vitellogenesis, 

and are ready to undergo maturation under 

the right stimulation. The graph demonstrates how 

MH-IVFs are feasible monthly: it shows that batches 

of potentially fertilisable oocytes are present each 

month in ovaries of H. scabra. Looking at the survey 

results, one can observe that more than 30% of the 

females have batches of oocytes in their ovaries waiting 

to enter maturation at almost any time of the year. 

Table 1 shows that the process is effective on 13 aspidochirote 

species tested so far (Léonet et al. 2009). The 

species were from the genera Actinopyga, Holothuria, 

Thelenota and Pearsonothuria. Interestingly, the 

method was successful on H. fuscogilva, a species of 

very high value. No Stichopus species were tested. 

– 

Mature 

Fertilised 

b 

+ 

b 

– 

SW DMP 1-MeA L-cys DTT MH ind 

44 

a 

– 

b 

– 

a + 

Figure 3 illustrates the hatchery production 

obtained in MH.SA from January 2009 to February 

2010. During 2009, MH.SA carried out 29 IVFs, 

sacrificing 32 females and 24 males. The production 

of 4,942,876 embryos transformed into 278,486 

6-day-old auricularia, then 164,545 1-day-old 

post-metamorphic juveniles and 48,857 1-cm-long 

juveniles. These juveniles were transferred into ponds 

for pre-growing. The average monthly production 

of juveniles via MH-IVF is about 4,000 1-cm-long 

individuals up to a maximum of 8,000 (in a hatchery 

where the wet room is 70 m 2). 

Comparison of the methods 

Spawning induction methods are not effective outside 

the spawning period (Table 2). The sea cucumber 

spawning period varies from one species to another, 

and seems to be extended when the population 

is located close to the equator. The farther the

Percentage 

100 

80 

60 

40 

20 

0 

Nov-98 

Dec-98 

Jan-99 

Feb-99 

Mar-99 

Apr-99 

May-99 

Jun-99 

Jul-99 

Aug-99 

Sep-99 

Oct-99 

Nov-99 

Dec-99 

Jan-00 

Feb-00 

Mar-00 

Apr-00 

May-00 

Jun-00 

Jul-00 

Aug-00 

Sep-00 

Oct-00 

Nov-00 

Dec-00 

Jan-01 

Feb-01 

Mar-01 

Apr-01 

Figure 2. Ovarian maturity in the Holothuria scabra population of Toliara (Madagascar) (Rasolofonirina et 

al. 2005). At each period of the survey, the ovaries of 30 females were sectioned, analysed and 

characterised into five stages (post-spawning, resting, growing, mature and spawning). The ovaries 

of the stages post-spawning (black and white striped) and resting (white) include mainly oogonia and 

young oocytes. The ovaries of the stages growing (green), mature (spotted red) and spawning (plain 

red) include many oocytes that have completed vitellogenesis. 

populations are from the equatorial line, the more difficult 

the spawning induction methods are to apply. For 

example, it is easy to obtain eggs from H. scabra in 

the Philippines with thermal shocks (R. Gamboa, pers. 

comm.) but hard in Toliara (Madagascar) or Mascat 

(Oman) with the same method. It seems also to be 

true for I. fuscus, where the spawning season extends 

45 

Period 

Table 1. Maturation rate (%) of oocytes from various sea cucumber species incubated 

with the MH inductor. Control is the rate of oocyte maturation in filtered sea 

water (n = number of individuals tested) (modified from Léonet et al. 2009) 

Species Maturation (%) Control (%) 

Actinopyga echinites (n=3) 81.00 31.00 

Bohadschia subrubra (n=2) 99.00 9.00 

Bohadschia vitiensis (n=4) 87.42 9.65 

Holothuria cinerascens (n=3) 92.60 12.30 

Holothuria edulis (n=2) 92.00 11.00 

Holothuria forskali (n=2) 94.50 7.00 

Holothuria fuscogilva (n=5) 80.00 10.00 

Holothuria leucospilota (n=4) 70.25 6.00 

Holothuria maculosa (n=6) 63.35 9.20 

Holothuria scabra (n=4) 92.25 15.75 

Holothuria tubulosa (n=4) 82.00 24.25 

Pearsonothuria graeffei (n=3) 92.00 32.00 

Thelenota ananas (n=3) 79.33 32.66 

through the year in Galapagos (Torral-Granda and 

Martinez 2007) but is restricted to July–September in 

Baja California (Herrero-Pérezrul et al. 1999). 

The reliability of thermal shocks, even within 

the spawning period, is quite random (Table 2). The 

use of a substance to inject into the coelom or for 

incubation is much more reliable once the appropriate

Number of juveniles 

60,000 

50,000 

40,000 

30,000 

20,000 

10,000 

0 

J F M A M J J A 

Month 

Figure 3. Production of 1-cm-long juveniles from the Madagascar Holothurie S.A. hatchery 

during 2009: blue line = monthly production; red line = cumulative production 

concentration is known. The PCF method is actually 

difficult to apply in aquaculture as it requires PCF 

from animals in spawning posture, and that is not 

always easy to find. For this method to be effective in 

aquaculture, the bioactive molecule in the PCF needs 

to be identified. 

The three methods of spawning induction involved 

genitors that are kept in a large volume of sea water 

(often tanks with a few hundred litres). The fertilised 

eggs are collected at the end of the process through 

the use of various filtration procedures. During filtration, 

all microbes (bacteria, protozoans and small 

metazoans such as copepods) are retained with the 

fertilised eggs. Non-fertilised eggs stay in the filtrates 

and degrade during the next hours of the process. 

Therefore, the risk of infestation is high with spawning 

induction methods and very low in IVF methods 

because the latter require 1–2 L of 1-µm filtered sea 

water at most (Table 2). 

The risk of larval malformation is minimal for 

spawning induction methods and for both GSSL-IVF 

and MH-IVF. However, it is high for IVF methods 

that use chemicals such as DTT, dimercaptopropanol 

(BAL), L-cysteine or 1-MeA. 

With respect to genetic issues, IVFs are no more 

influential on genetic drift than are the spawning 

induction methods. Genetic drift is a change in the 

frequency of alleles in a population. When populations 

are smaller, as is the case in aquaculture breedings, 

the effect of genetic drift is greater and may 

cause alleles to disappear completely, thus reducing 

genetic diversity. The reduction of genetic diversity 

46 

S O N D J F 

can be a problem in the production of individuals 

less adapted to cope with environmental variation. In 

IVFs, as in spawning induction methods, genetic drift 

could be a problem in the future, and the only way 

to overcome it is to pay attention to not always using 

genitors from the same parental lineage. In MH.SA, 

IVFs are done with genitors from previous generations, 

but gametes are also mixed with those from 

wild strains: gonads of wild strains are obtained from 

fishermen, who usually discard them as they use only 

the body wall of sea cucumbers to prepare trepang. 

In conclusion, IVF methods, especially MH-IVF, 

are simple, cost-efficient, allow the collection of 

fertilised eggs of sea cucumbers year round, and 

enable control of the basic operations in hatcheries. 

MH-IVF does not require high-tech equipment and 

is useful in both large- and small-scale hatcheries. It 

ensures a high degree of control at the very beginning 

of the work on the number and type of genitors (i.e. 

sex, length, weight, colour); the quality of the gonads 

(healthy versus parasitised); and the number, size and 

quality of spermatozoa and eggs. IVF necessitates 

the sacrifice of very few genitors compared with the 

individuals obtained and sacrificed for production 

(in 2009 the IVF sacrifices reached 0.1% of the 

production; the body walls of animals sacrificed for 

IVF were processed into trepang and entered into the 

production).

Table 2. Efficiency of the methods that allow sea cucumber aquaculturists to obtain fertilised eggs 

Tested species References 

Risk of larval 

malform ations 

Risk of 

infestation 

Reliability 

inside 

spawning 

period 

Methods Details Useful 

outside 

spawning 

period 

– – + – Various species including Hamel et al. (2002) 

Apostichopus japonicus, 

Holothuria scabra and 

Isostichopus fuscus 

PCF Injection into 

– – + – Bohadschia argus 

Mercier and Hamel 

coelomic cavity 

B. marmorata 

(2002) 

Holothuria leucospilota 

H. atra 

Cubifrin Injection into 

– + + – A. japonicus Fujiwara et al. (2010) 

coelomic cavity 

Kato et al. (2009) 

In-vitro fertilisation 

GSSL-IVF Incubation of gonadal – + – – A. japonicus Katow et al. (2009) 

tubules 

MH-IVH Incubation of oocytes + + – – 13 species 

Léonet et al. (2009) 

(see Table 1) 

Spawning induction 

Thermal shocks Transfer into tanks of 

various temperatures 

47 

DTT-IVF Incubation of oocytes + + – + H. scabra 


A. japonicus 

Karaseva and 

H. leucospilota 

Khotimchenko (1995) 

H. pardalis 

Maruyama (1980) 

Other inductors Incubation of oocytes – – – + H. scabra 


(BAL, 

H. leucospilota 

Maruyama (1980) 

L-cystéine, 

H. pardalis 

1-MeA) 

PCF = perivisceral coelomic fluid; GSSL-IVF = gonad-stimulating substance-like in-vitro fertilisation; MH-IVH = Madagascar Holothurie S.A. in-vitro fertilisation; DTT-IVF = dithiothreitol in-vitro 

fertilisation; BAL = dimercaptopropanol; 1-MeA = 1-methyladenine


This work has received the support of the Fonds 

National de la Recherche Scientifique (FNRS) and 

Commission Universitaire pour le Développement 

(CUD) through various grants and funding. 

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Evaluation of nutritional condition of 

juvenile sandfish (Holothuria scabra) 

Satoshi Watanabe 1*, Jacques M. Zarate 1,2, 

Maria J.H. Lebata-Ramos 2 and Marie F.J. Nievales 3 

Abstract 

It is important to accurately evaluate the wellbeing or nutritional condition of organisms when monitoring 

the wild stock conditions and improvement in aquaculture techniques; however, reliable nutritional condition 

indexes have not been established for sea cucumbers. In this study, the effects of starvation on condition factor 

(body weight / body volume), coelomic fluid constituent (protein, carbohydrate and cholesterol) concentrations 

and coelomic fluid density were analysed in an attempt to establish a method to determine nutritional 

condition in juvenile sandfish (Holothuria scabra). Body length, breadth and weight of juveniles produced 

at the sea cucumber hatchery of the Aquaculture Department, Southeast Asian Fisheries Development 

Center, were measured after anaesthetisation with 2% menthol-ethanol. Coelomic fluid protein level was 

analysed by the bicinchoninic acid method. Carbohydrate level was analysed by the phenol – sulfuric acid 

method. Cholesterol level was analysed by the Zak method. Coelomic fluid volume and coelomic fluid weight 

were measured. Starvation caused a concomitant decrease in body length, breadth and weight, resulting 

in no net change in the condition factor. This result indicated that condition factor cannot be used as a 

nutritional condition index. Coelomic fluid constituent level could be measured with a small volume of 

sample (i.e. 10–20 µL). Although no clear pattern was observed in coelomic fluid protein and cholesterol 

levels during the starvation trial, carbohydrate level increased, as did coelomic fluid density. These results 

suggest that coelomic fluid density and carbohydrate level may be used as indexes for nutritional condition 

of sandfish without sacrificing the animal. 

Introduction 

Due to overexploitation and increasing demand, 

fishery stocks of many tropical sea cucumber species 

have declined drastically in the Pacific and Indian 

oceans (Carpenter and Niem 1998; Hamel et al. 2001; 

Conand 2004). In order to increase the fishery production, 

many studies have been done on hatchery, 

aquaculture and stock enhancement methods of sea 

1 Japan International Research Center for Agricultural 

Sciences, Tsukuba, Ibaraki, Japan 


2 Aquaculture Department, Southeast Asian Fisheries 

Development Center, Tigbauan, Iloilo, Philippines 

3 Division of Biological Sciences College of Arts and 

Sciences, University of the Philippines Visayas, Miagao, 

Iloilo, Philippines 

50 

cucumbers, especially sandfish (Holothuria scabra), 

which is the most valued of tropical sea cucumbers 

(e.g. Battaglene et al. 1999; Mercier et al. 1999; 

Purcell et al. 2006; Bell et al. 2007). Nevertheless, 

there is a basic methodological problem: there has 

been no standard evaluation method developed for 

nutritional condition in sea cucumbers, including 

H. scabra. Hatcheries for H. scabra have been operating 

in countries such as New Caledonia, Vietnam, 

India and the Philippines (James 1999; Pitt and Duy 

2004; Agudo 2006; Duy 2010). Slow growth and high 

mortality of the cultured juveniles are problematic in 

these hatcheries—the growth of juveniles can sometimes 

be faster in an earthen pond where supplemental 

feeding is not conducted than in concrete tanks under 

controlled conditions (SEAFDEC–AQD, pers. comm.; 

Pitt et al. 2001; Agudo 2012). Therefore, hatchery

techniques, particularly feeding methods, should be 

improved. It is also crucial to establish a method to 

monitor the condition of released juveniles in stock 

enhancement programs. 

In this study, attempts were made to establish a 

method to evaluate nutritional condition of sandfish 

based upon body size to weight relationship and 

concentration of coelomic fluid constituents. 

Materials and methods 

Measurements of body size, coelomic fluid 

volume and coelomic fluid density 

In order to acquire basic information about the relationship 

between body size and coelomic fluid, data on 

H. scabra juveniles obtained from the sea cucumber 

hatchery of the Southeast Asian Fisheries Development 

Center – Aquaculture Department (SEAFDEC–AQD) 

in Iloilo, the Philippines, were collected. To increase 

body measurement accuracy, the juveniles were 

anaesthetised using a standard anaesthetic solution: 

ethanol saturated with menthol (i.e. 0.56 g menthol 

crystal dissolved in 100 mL of 99% ethanol) and 

diluted with filtered sea water to 2% (Yamana et al. 

2005). H. scabra (n = 15) were placed in the solution 

at room temperature for 20 minutes. After blotting dry 

with paper towels, body length (BL) and body breadth 

at the widest point (BB) were measured to the nearest 

0.01 mm, and body weight (BW) was measured to the 

nearest 0.01 mg. Body volume (BV) was calculated as 

a spheroid according to equation (1): 

BV = 4/3 × π × BL × (BB/2) 2 (1) 

Fulton’s condition factor (K) was calculated 

according to equation (2): 

K = BW/BV ×104 (2) 

Holothuria scabra were then cut longitudinally at the 

abdomen, and total coelomic fluid was collected with 

a micropipette into a micro centrifuge tube. Coelomic 

fluid volume (CFV) was measured to the nearest 10 µL 

with micropipettes. Coelomic fluid weight (CFW) was 

measured to the nearest 0.001 mg with a microbalance. 

Effects of starvation on condition of H. scabra 

Holothuria scabra juveniles of similar sizes 

obtained at the SEAFDEC–AQD sandfish hatchery 

(n = 30) were anaesthetised as described above and 

body sizes were measured (i.e. BL, BB and BW). For 

the initial data, five individuals were stored at –80 ºC. 

51 

The rest of the H. scabra were individually placed 

in containers made of PVC pipe (10 cm diameter 

× 5 cm length) with both ends covered with 5-mm 

mesh (Figure 1). The containers were placed in a 

60-L fibreglass tank (5 containers in each of 5 tanks) 

and kept under flow-through conditions with aeration 

but no sediment or supplementary feeding. Tank sea 

water was sand-filtered, further filtered with 10-µm 

and 1-µm filters, and UV-treated. Size measurements 

were made every 2 days on the same individuals after 

anaesthetisation, and five individuals (i.e. one tank) 

were stored at –80 ºC every 2 days until day 10. 

At the conclusion of the trial, the frozen samples 

were thawed in a refrigerator and longitudinally cut at 

the abdomen. Coelomic fluid was collected to measure 

protein, carbohydrate and cholesterol concentrations: 

• Protein concentration of coelomic fluid was measured 

by the bicinchoninic acid (BCA) method (QuantiPro 

BCA Assay Kit, SIGMA-ALDRICH). A 10-µL 

aliquot of coelomic fluid was diluted 100 times with 

distilled water in 1.5-mL microtubes, and absorbance 

was read at 562 nm using a microplate reader. 

• Carbohydrate concentration of the coelomic fluid 

was measured by the modified phenol – sulfuric 

acid method (Kushwaha and Kates 1981). A 10-µL 

aliquot of the coelomic fluid was mixed with 40 µL 

distilled water, 20 µL 5% phenol solution and 

100 µL concentrated H 2SO 4 in 2-mL microtubes, 

vortexed, and incubated in an 80 °C block heater 

for 10 minutes. Absorbance was read at 490 nm 

against a blank, using a microplate reader. 

• Cholesterol concentration of the coelomic fluid was 

measured by the modified Zak method (Zak 1957; 

Altescu 1965). A 20-µL aliquot of the coelomic 

fluid was mixed with 300 µL 0.2% CuCl 2 •2H 2O 

in 99% ethanol and 200 µL concentrated H 2SO 4 

in 1.5-mL microtubes, and incubated in an 80 °C 

block heater for 10 minutes. Absorbance was read 

at 540 nm against a blank, using a microplate reader. 

Filters Fibreglass tank Samples 

10 µm 

1 µm 

UV 

Figure 1. Schematic drawing of the sandfish rearing 

system used in this study

Effects of starvation on coelomic fluid 

volume and coelomic fluid density 

To determine changes in coelomic fluid density 

(CFD) and CFV relative to the body size (CFV '), 

another starvation trial was conducted for 20 days. 

Body size measurements were made after anaesthetisation 

(n = 25) and five individuals were stored 

at –80 ºC for the initial data. In each of four 60-L 

fibreglass tanks, five individuals were placed (not 

individually separated). Every 5 days, five individuals 

(i.e. all five individuals from one tank) were 

measured and stored at –80 ºC. The frozen samples 

were thawed in a refrigerator; total coelomic fluid 

was drawn from the body cavity to measure CFV and 

CFW. CFD was obtained as CFW/CFV. CFV ' was 

calculated as CFV/BV. 

Statistical analysis 

Relationships between the studied parameters were 

examined by linear, hyperbolic or exponential regression 

analyses. For comparisons of more than three 

datasets, ANOVA was performed followed by a Tukey 

test for posteriori comparisons. For comparisons of 

paired data sets, t-tests were used. Differences were 

considered significant if P < 0.05. 

Results and discussion 

Body size, coelomic fluid volume, coelomic 

fluid density and condition factor 

CFV of H. scabra had a significant positive correlation 

with BL (Figure 2, equation (3)): 

CFV = 1.73 × e0.11BL (3) 

CFV increased linearly as BW (Figure 2, equation 

(4)): 

CFV = 123.0 × BW – 93.7 (4) 

and BV (equation (5)) increased: 

CFV = 0.01 × BV – 60.40 (5) 

This is common for many animals since BV and 

BW increase exponentially with BL. 

There were no significant correlations between 

CFD and BL (r2 = 0.13, P = 0.19), BW (r2 = 0.058, 

P = 0.39) or BV (r2 =0.068, P = 0.35). 

Condition factor (K) had a significant negative 

linear correlation with BL (Figure 2), BV and BW, 

according to equations (6), (7) and (8), respectively: 

52 

K = –0.01 × BL + 1.22 (6) 

K = –2.8×10 -6 × BV + 1.05 (7) 

K = –0.0032 × BW + 1.05 (8) 

Since K is correlated with BL, BV and BW, it must be 

standardised for size and weight if it is to be used for 

condition comparisons of H. scabra of different sizes. 

Starvation, condition factor and coelomic 

fluid constituent concentrations 

BV and BW of individual H. scabra decreased 

concomitantly during the 10-day starvation period 

(Figure 3). While BW gradually decreased over the 

experimental period, the trend in BV was less clear, 

perhaps due to limited accuracy of body size measurements 

despite anaesthetisation. The plasticity of 

the body shape of sea cucumbers is problematic for 

size measurements (Sewell 1990; Battaglene et al. 

1999). Nevertheless, both mean BV and BW significantly 

decreased in 10 days (P < 0.05 and P < 0.01, 

respectively, t-test). Because of this, K stayed constant 

during the starvation period (Figure 3), with 

no significant difference between day 1 and day 

10 (P = 0.16, t-test). K is one of the most widely 

used indexes for determination of condition, wellbeing 

or ‘plumpness’ of organisms in fisheries and 

general fish biology studies (e.g. Nash et al. 2006). 

However, unlike vertebrates and invertebrates with 

exoskeletons, K is not a useful index for the evaluation 

of nutritional condition in H. scabra because of 

the concomitant changes in body size and weight. 

Protein and cholesterol concentrations in the coelomic 

fluid of H. scabra initially increased and then 

decreased after day 6 during the 10-day starvation 

period (Figure 4), according to equations (9) and 

(10): 

C p = –0.050 × d 2 + 0.53 × d + 2.70 (9) 

Cch = –0.0016 × d2 + 0.021 × d + 0.17 (10) 

where Cp is protein concentration and Cch is cholesterol 

concentration, and d is day of starvation. 

Therefore, it is difficult to use them as indexes of 

nutritional condition in H. scabra. On the other hand, 

carbohydrate concentration (Cc) increased linearly 

(Figure 4) as starvation continued, according to 

equation (11): 

C c = 0.076 × d + 0.86 (11)

Coelomic fluid volume 

(µL) 


(µL) 


(µL) 

1,200 

1,000 

800 

600 

400 

200 

0 

r = 0.91 

P < 0.0001 

20 30 40 50 60 70 

Body length (mm) 

Body volume (mm3 1,200 

1,000 

800 

600 

400 

200 

0 

r = 0.84 

P < 0.001 

0 50,000 

) 

100,000 

1,200 

1,000 

800 

600 

400 

200 

0 

r = 0.79 

P < 0.001 

0 2 4 6 8 

Body weight (g) 

Therefore, C c may be suitable for determination 

of nutritional condition. Reasons for increased C c 

despite starvation are not known. In fact, C c in the 

coelomic fluid in Japanese sea cucumber Stichopus 

japonicus is reported to decrease and non-protein 

nitrogen level stay constant during starvation (Tanaka 

1958). Further studies on the physiological processes 

of H. scabra during starvation are needed. 

Starvation, coelomic fluid volume and 

coelomic fluid density 

CFD had a significant positive linear correlation 

with the starvation period (Figure 5), according to 

equation (12): 

CFD = 0.0087× d + 0.92 (12) 

CFV ', on the other hand, had a significant negative 

linear correlation with the starvation period (Figure 

4) according to equation (13): 

53 

K (g/mm 3 ×10 4 ) 

K (g/mm 3 ×10 4 ) 

K (g/mm 3 ×10 4 ) 

1.2 

1.1 

1.0 

0.9 

0.8 

0.7 

0.6 

r = –0.68 

P < 0.01 

20 30 40 50 60 70 

Body length (mm) 

1.2 

1.1 

1.0 

0.9 

0.8 

0.7 

0.6 

Body volume (mm3 r = –0.76 

P < 0.001 

0 50,000 

) 

100,000 

1.2 

1.1 

1.0 

0.9 

0.8 

0.7 

0.6 

r = –0.69 

P < 0.01 

0 2 4 6 8 

Body weight (g) 

Figure 2. Relationships between body size and coelomic fluid volume and condition factor (K) in 

Holothuria scabra (n = 15) 

CFV ' = –0.0015× d + 0.084 (13) 

These relationships may indicate that increased C c 

due to starvation may be related to thickening of the 

coelomic fluid. In addition, since protein is reported 

to be the major energy source for small Apostichopus 

japonicus (synonym for S. japonicus) during aestivation 

(Yang et al. 2006), the protein concentration may 

increase during the initial phase of starvation due to 

thickening of the coelomic fluid, and subsequently 

decrease due to energy consumption. 

Recommended index for nutritional 

condition 

Although mechanisms of changes in coelomic 

fluid constituent concentrations during starvation are 

not understood, the Cc seems to be a good indicator of 

nutritional condition in H. scabra. Since it requires a 

very small amount of coelomic fluid sample (10 µL) 

for the colorimetric carbohydrate measurement, it

Body volume (mm 3 ) 

Body volume (mm 3 ) 

K (g/mm 3 ×10 4 ) 

12,000 

10,000 

8,000 

6,000 

4,000 

2,000 

0 

8 

6 

4 

2 

0 

0.9 

0.8 

0.7 

0.6 

0.5 

0.4 

0 

0 

0 

2 4 6 8 10 

Starvation (days) 

2 4 6 8 10 


2 4 6 8 10 


Figure 3. Changes in body volume, body weight 

and condition factor (K) of Holothuria 

scabra (n = 5) during a 10-day starvation 

trial. Different symbols refer to specific 

individuals. 

may be possible to monitor the time-course change of 

nutritional condition of an individual without sacrificing 

it. A method to sample the coelomic fluid using 

cannulation from live specimens should be further 

investigated. Although CFD may also be a good 

indicator of nutritional condition, it requires a larger 

amount of sample for the measurement. In this study, 

the entire coelomic fluid of each individual was used 

for the density measurement to increase accuracy of 

the measurements. While the use of more sensitive 

devices may increase the measurement accuracy of 

CFD, colorimetric methods are recommended. 

Studies on improvement of H. scabra production at 

hatcheries and aquaculture facilities, as well as stock 

54 

Protein (mg/mL) 

Cholesterol (mg/mL) 

Carbohydrate (mg/mL) 

6 

5 

4 

3 

2 

1 

0 

0.35 

0.30 

0.25 

0.20 

0.15 

2 

4 6 


0.10 

0 2 4 6 8 10 


2.0 

1.5 

1.0 

r = 0.62 

P < 0.001 

r = 0.58 

P < 0.001 

enhancement technologies, should be carried out with 

the methods for monitoring H. scabra conditions 

described here. 


8 10 

0.5 

0 

r = 0.73 

P < 0.0001 

0 2 4 6 8 10 


Figure 4. Relationships between starvation period 

and levels of protein, cholesterol and 

carbohydrate in the coelomic fluid of 

Holothuria scabra 

The authors are grateful to Joemel Sumbing, Jesus 

Rodriguez, Rema Sibonga, Harold Figurado and Roy 

Hipolito at SEAFDEC–AQD for assistance in sandfish 

culture and laboratory analysis. This study was 

funded by the Japan International Research Center 

for Agricultural Sciences (JIRCAS).

Coelomic fluid density 

(mg/mL) 

Coelomic fluid volume/ 

body volume (µL/mm3 ) 

1.3 

1.2 

1.1 

1.0 

0.9 

0.8 

0 

0.12 

0.08 

0.04 

r = 0.72 

P < 0.0001 

5 10 15 


0 

0 5 10 15 20 


Figure 5. Relationships between starvation period 

and coelomic fluid density and coelomic 

fluid volume relative to body volume of 

Holothuria scabra 

References 

r = –0.44 

P < 0.05 





Agudo N.S. 2012. Pond grow-out trials for sandfish 

(Holothuria scabra) in New Caledonia. In ‘Asia–Pacific 





Altescu E.J. 1965. New reagent for the direct determination of 

serum cholesterol. Journal of Clinical Pathology 18, 824. 


Survival and growth of cultured juvenile sea cucumbers 


Bell J.D., Agudo N.S., Purcell S.W., Blazer P., Simutoga M., 




509–519. 

Carpenter K.E. and Niem V.H. 1998. The living marine 

resources of the Western Central Pacific, Volume 2: 

Cephalopods, crustaceans, holothurians and sharks. FAO 

species identification guide for fishery purposes. Food and 


20 

55 









scabra) in Vietnam. Aquaculture Extension Manual 48. 

Southeast Asian Fisheries Development Center: Iloilo, 

Philippines. 





James D.B. 1999. Hatchery and culture for the sea cucumber 

Holothuria scabra Jaeger in India. Naga, ICLARM 

Quarterly 22, 12–16. 

Kushwaha S. C. and Kates M. 1981. Modification of 

phenol-sulfuric acid method for the estimation of sugars 

in lipids. Lipids 16, 372–373. 

Mercier A., Battaglene S.C. and Hamel J.-F. 1999. Daily 

burrowing cycle and feeding activity of juvenile sea 

cucumbers Holothuria scabra in response to environmental 

factors. Journal of Experimental Marine Biology 

and Ecology 239, 125–156. 

Nash R.D.M., Valencia A.H. and Geffen A.J. 2006. The 

origin of Fulton’s condition factor—setting the record 

straight. Fisheries 31, 236–238. 













evaluation of co-culture of juvenile sea cucumbers, 

Holothuria scabra (Jaeger), with juvenile blue shrimp, 



Sewell M.A. 1990. Aspects of the ecology of Stichopus mollis 

(Echinodermata: Holothuroidea) in north-eastern New 

Zealand. New Zealand Journal of Marine and Freshwater 


Tanaka Y. 1958. Feeding and digestion processes of 

Stichopus japonicus. Bulletin of Faculty of Fisheries 

Hokkaido University 9, 14–28. 

Yamana Y., Hamano T. and Yamamoto K. 2005. Anesthetizer 

of the adult sea cucumber Apostichopus japonicus. 

Nippon Suisan Gakkaishi 71, 299–306. (in Japanese 

with English abstract)

Yang H., Zhou Y., Zhang T., Yuan X., Li X., Liu Y. et 

al. 2006. Metabolic characteristics of sea cucumber 

Apostichopus japonicus (Selenka) during aestivation. 

Journal of Experimental Marine Biology and Ecology 

330, 505–510. 

Zak E. 1957. Simple rapid microtechnic for serum total 

cholesterol. American Journal of Clinical Pathology 27, 

583–588. 

56

Ocean nursery systems for scaling up juvenile 

sandfish (Holothuria scabra) production: 

ensuring opportunities for small fishers 

Marie Antonette Juinio-Meñez 1*, Glycinea M. de Peralta 1, Rafael Junnar P. 

Dumalan 1, Christine Mae A. Edullantes 1 and Tirso O. Catbagan 1 

Abstract 

Cost-effective production of juveniles to release size (>3 g) is a primary objective in the culture of Holothuria 

scabra. Ocean nursery systems were developed to help overcome the space limitations of a small hatchery setup 

and shorten the rearing period in the hatchery. The growth and survival of first-stage juveniles (4–10 mm) 

in two ocean nursery systems—floating hapas and bottom-set hapa cages—were compared with those reared 

in hapa nets in a marine pond. Juveniles reared in these nursery systems were healthy and in good condition. 

Survival was not substantially different in hapa nets in marine ponds and floating hapas. However, growth 

in pond hapa nets was higher than in the two ocean nursery systems. Nonetheless, the estimated cost of 

producing juveniles in the floating hapa system is considerably cheaper compared with those reared in the 

other systems. Moreover, local community partners easily maintained the floating hapas and reared the 

juveniles to release size. Further, the effects of sand conditioning on juvenile quality were also investigated. 

The growth of sand-conditioned juveniles was higher than unconditioned ones in hatchery tanks, and more 

conditioned juveniles buried within the first hour of release in the field. From floating hapas, juveniles 

can be conditioned in sea pens for at least 1 week, or reared to bigger sizes for 1–2 months (>20 g) prior 

to release. However, whether this intermediate rearing procedure will be practical with large numbers of 

juveniles needs to be considered. Results show that ocean nursery systems are simple and viable alternative 

systems for scaling up juvenile sandfish production compared with hapas in marine ponds, which might not 

be available and accessible to small fishers. 

Introduction 

The sea cucumber fishery is a source of livelihood 

to many coastal dwellers and the basis of a multimillion 

dollar trepang industry in the Philippines 

(Gamboa et al. 2004). Various coastal towns, cities 

and provinces all over the country have been reported 

to engage in significant sea cucumber collection 

and processing activities (e.g. Trinidad-Roa 1987). 

Intense harvesting, unsustainable fishery practices 

and increasing demand for sea cucumber products 




57 

in international trade have resulted in a progressive 

decline in sea cucumber stocks and the overexploitation 

of high-value species. 

With the decline in the sea cucumber stocks, 

restocking hatchery-produced juvenile sea cucumbers 

is seen as a means to rebuild wild stocks 

(Battaglene 1999). At present, Holothuria scabra is 

the only species of tropical sea cucumber that can 

be mass cultured in the hatchery (see references in 

Lovatelli et al. (2004)). 

The culture technology for sandfish was initially 

developed in India (James 1999, 2004) and then in 

Solomon Islands (Battaglene 1999). Culture protocols 

were further refined in New Caledonia (Agudo 

2006) and Vietnam (Pitt and Duy 2004; Duy 2010).

In the Philippines, experimental-scale trials of 

sandfish culture were initiated in 2000 (Gamboa and 

Juinio-Meñez 2003), and efforts to scale up juvenile 

production and expand community-based searanching 

activities are ongoing. Hatchery culture protocols 

based on various methods reported from other 

hatcheries were modified and adapted to optimise 

larval and early juvenile rearing at the University of 

the Philippines Marine Science Institute’s (UPMSI) 

Bolinao Marine Laboratory (BML). However, the 

costs of producing juveniles in the hatchery and 

marine ponds were high. Scaling up production was 

further constrained by space limitations in a small 

hatchery set-up. Given these considerations, ocean 

nursery systems designed to shorten the juvenile 

rearing period in the hatchery and reduce the cost 

of production were investigated. In addition, since 

production of juveniles is intended primarily for 

community-managed sea ranching, mechanisms to 

engage local partners in early juvenile rearing were 

deemed to be strategic in enhancing ownership of 

these initiatives. 

Hatchery culture of H. scabra 

at the UPMSI Bolinao Marine 

Laboratory 

The current techniques used for broodstock spawning 

and rearing juvenile sandfish are described here. For 

each spawning induction, 40–50 wild broodstock 

(>200 g) are acquired from fishers, and are maintained 

in sea pens near the hatchery facility or in 

concrete tanks in the hatchery for 2–4 weeks prior 

to spawning induction. Broodstock are successfully 

induced to spawn within 3–4 days using a combined 

treatment of desiccation, thermal shock and food 

shock (Spirulina) (Agudo 2006) at any time of the 

year. 

The developing larvae are reared in larval tanks 

with moderate aeration and shading at a stocking density 

of 0.3–0.5 fertilised egg/mL. Larvae are cultured 

in static conditions with daily partial water change 

(30–50%) using UV-treated sea water (UVSW). A 

mixture of Isochrysis galbana and Chaetoceros calcitrans 

at a density of 10,000–15,000 cells/mL is fed to 

the larvae twice a day as they develop. Under optimal 

conditions (28–30 °C and 32–34 ppt), the auricularia 

larvae start to metamorphose to doliolaria stage by 

day 10. General cleaning of the tanks is done prior 

to introduction of Spirulina-coated settlement plates 

58 

in the larval rearing tanks. The plates are introduced 

when >50% of the larvae have reached the pentactula 

stage, usually within 12 days of fertilisation. Both 

sides of the corrugated plastic settlement plates are 

coated with Spirulina paste (i.e. Spirulina powder 

dissolved in a small volume of fresh water) and airdried 

for 30–60 minutes (Duy 2010). Before being 

placed in the larval-rearing tanks, settlement plates 

are soaked in tanks with flow-through UVSW for 

30 minutes. The amount of C. calcitrans and I. galbana 

provided to the larvae twice a day is adjusted 

to 20,000–30,000 cells/mL when most larvae have 

settled by day 15. The diatom Navicula ramossissima 

and Sargassum extract are also provided as supplemental 

food for the post-settled juveniles. 

This method resulted in a fivefold increase in survival 

from fertilised eggs to second-stage juveniles 

from year 1 to year 3 (Table 1). This is attributed 

to the low initial stocking density currently being 

used in the facility (0.3–0.5 fertilised egg/mL), the 

use of Spirulina-coated plates to induce settlement, 

and the extended use of C. calcitrans combined with 

N. ramossissima to feed the newly settled juveniles. 

Periodically, Sargassum extract was also provided 

as supplemental food. Survival from first-stage 

to second-stage also improved by 95% by year 3. 

Increase in the number of second-stage and releasesize 

juveniles was largely due to the development of 

ocean nursery systems in Bolinao, which addressed 

the problem of slow growth and low survival due 

to limitation in hatchery space (i.e. high density 

stocking in tanks) as described below. As a result, 

fewer batches of larvae had to be reared per year, 

significantly reducing time and effort in the hatchery 

operations. 

Ocean nursery systems 

In the first year of production, early juveniles were 

reared to a release size of >3 g in the land-based 

hatchery tanks. Rearing to release size in the hatchery 

involved growing post-settled juveniles in settlement 

tanks with benthic diatoms and supplementing with 

Sargassum extract up to 90 days until the juveniles 

reached ~1.0 g. The juveniles were then transferred 

to tanks with sediment and sand-filtered sea water. 

Daily feeding of diatoms and periodic addition of 

ground Sargassum enriched the sediment in the 

tanks. Both growth rate and survival were low due to 

difficulties in producing sufficient benthic diatoms 

and maintaining good water quality in the tanks with

Table 1. Juvenile production in the Bolinao outdoor hatchery facility from May 2007 to April 2010 

Spawning trial Number 

of batches 

Fertilised egg 

count 

(millions) 

sediment, even with a flow-through system. After the 

study visit at the Research Institute for Aquaculture 

No. 3 (RIA3) in Nha Trang, Vietnam, in June 2008, 

most of the first-stage juveniles (4–10 mm) were 

reared in hapa nets in a marine pond following 

Vietnamese methods (Duy 2010). However, a suitable 

marine pond was about 100 km away from the BML 

hatchery—a travel time of ~2.5 hours. Thus, manpower 

resources and costs to transport juveniles were 

substantial. In addition, while survival was relatively 

high (60–73%), juvenile growth in the ponds was 

highly variable. Growth ranged from almost nil up 

to 6.1 g over 30 days. This variability was probably 

due to high temperatures (27–31 °C) and extreme 

fluctuations in salinity (13–29 ppt). 

Ocean nursery systems to increase juvenile production 

and reduce production costs for first-stage 

juveniles were investigated (Juinio-Meñez et al. 

2009). Bottom-set hapa cages, which were used 

to rear juveniles to >1.0 g during the experimental 

phase of sandfish culture in earlier trials, were 

modified to rear first-stage juveniles (4–10 mm). In 

addition, the use of floating hapas was pilot-tested. 

Initial trials conducted in high nutrient areas in 

northern Luzon showed that first-stage juveniles can 

grow up to ~1.0 g in 49 days in the floating hapas 

(Edullantes and Juinio-Meñez 2009). Subsequently, 

an experiment was conducted to compare growth and 

survival of first-stage juveniles in the three nursery 

systems—the hapa nets in ponds and the two ocean 

nursery systems (hapa cages and floating hapa nets). 

The same type of mesh was used for all set-ups. 

Stocking density relative to the estimated potential 

grazing area was 150 juveniles/m 2. The experiment 

ran for 30 days. Results showed that growth was 

higher in the hapa nets (0.6 g) in the pond than in the 

% survival 

to first stage 

(30 mm) 

Year 1 (May 2007 

– April 2008) 

8 22.23 0.76 0.11 16.08 12,468 


– April 2009) 

3 10.74 1.14 0.35 32.32 26,331 


– April 2010) 

3 7.10 2.08 0.67 31.44 32,433 

TOTAL 14 71,232 

Aside from scaling up juvenile production, improving 

the quality of released juveniles is crucial for 

successful sea ranching. Hatchery production of 

environmentally incompetent juveniles jeopardises 

restocking success (Battaglene and Bell 2004; Purcell

Table 2. Comparison of the different nursery systems (hapa nets in marine ponds, ocean floating hapas and 

bottom-set sea cages) using different criteria 

Criteria Nursery systems 

2004; Oliver et al. 2008). In the hatchery, additional 

conditioning regimes introduce extra expense, but 

this might be offset by improvements in growth and 

survival. To improve the quality of juveniles and 

increase survival in the wild, it has been proposed 

that hatchery individuals be conditioned to optimise 

morphological and behavioural traits (Delgado et 

al. 2002; Davis et al. 2005; Brokordt et al. 2006). 

While juveniles can be reared to a size of ~3 g in 

hapa nets in both ponds and ocean nursery systems, 

they are not exposed to sediment, and graze primarily 

on biofilm on the nets. Preliminary studies at BML 

showed that juveniles that were reared in tanks with 

sediment had thicker body walls and grew faster than 

those reared in tanks without sediment (Schagerstrom 

2003). Subsequent laboratory experiments showed 

that mean body weights of juveniles were substantially 

higher in the sand-conditioned treatment than 

those in treatments without sand. Moreover, up to 

60% of juveniles in the sand-conditioned treatment 

attained a weight of more than 3 g in 30 days, compared 

with only 23% in the treatment without sand 

(Dumalan et al. 2009). After 45 days in sea cages, 

the average weight of sand-conditioned juveniles was 

higher but, because of the high variability in growth 

among individuals, it was not substantially different 

from the average weight of juveniles that were not 

sand-conditioned in the laboratory prior to release. 

The average survival rates of sand-conditioned and 

unconditioned juveniles were also not different. 

However, post-released juveniles that were not 

sand-conditioned took a longer time to bury into 

60 

Hapa nets in 

marine ponds 

Ocean floating 

hapas 

Ocean bottomset 

cages 

Growth +++ ++ ++ 

Survivorship +++ +++ ++ 

Cost of materials and other inputs + +++ ++ 

Maintenance + +++ ++ 

Ease of retrieval +++ ++ + 

Adaptability (small-scale fishers) 

Other considerations 

+ +++ ++ 

Durability of nursery units ++ + +++ 

Changes in salinity, temperature, dissolved oxygen 

Rating: +++ = most desirable 

++ 

+ = least desirable 

+ ++ +++ 

the sediment (R. Dumalan, unpublished data). This 

indicates that, even if juveniles can be reared in hapa 

nets to a release size of >3 g, sand conditioning prior 

to release may be necessary to improve their survival 

in the wild. 

Proposed production scheme 

for juvenile sandfish for 

community-based grow-out 

Based on the results of different experiments 

conducted in the hatchery and the field, as well as 

experience with local small fishers, production of 

sandfish from a small hatchery can be made costeffective 

and accessible to small-scale fishers for 

community-based grow-out. The hatchery phase for 

larval rearing to post-settled stage (4–10 mm) will 

take 30–45 days. Post-settled juveniles can then be 

reared in ocean floating hapas (Figure 1) to a size 

of 2–3 g (25–30 mm) in 30–60 days. To condition 

juveniles with sediment and grow them to a bigger 

release size, the juveniles can be reared in bag nets 

or sea pens and retrieved after 15–30 days at sizes 

>20 g. This intermediate stage will substantially 

increase the survival of juveniles during the grow-out 

phase to marketable size. We recommend the release 

of these juveniles in suitable and well-managed 

sea-ranch areas. Based on experience in the pilot sea 

ranch, sandfish will attain sexual maturity within a 

year, and the first harvest of animals >320 g can be 

made after 1 year, with a subsequent harvest after

Figure 1. Ocean floating hapas within the communal sea-ranching site in Masinloc, Zambales 

another 6 months. Programmed releases and selective 

harvesting of sandfish >320 g can maintain a 

viable reproductive population in the sea ranch, thus 

optimising both ecological and economic returns (M. 

Juinio-Meñez, unpublished data). 


The authors are grateful for financial and institutional 

support for the hatchery operations, and 

scaling up of juvenile production and development 

of the ocean nursery systems, from the University 

of the Philippines Marine Science Institute, the 


Research (ACIAR) and the Department of Science 

and Technology through the Philippine Council for 

Marine and Aquatic Research and Development. 

The sand-conditioning studies were supported 

with funds from the Department of Agriculture 

Bureau of Agricultural Research. Ms Elsie Tech 

provided invaluable technical assistance in scaling 

61 

up and maintaining the quality of the algal culture 

system for the hatchery phase. The assistance of 

Mr Florando Castro Jr and Ms Lyne Suriaga in the 

hatchery operations, as well as other members of 

the sea cucumber research team for field operations, 

was invaluable. Travel support for the participation 

of M.A. Juinio-Meñez in the symposium was also 

provided by ACIAR. 

References 

Agudo N.S. 2006. Sandfish hatchery techniques. The 


Research, Secretariat of the Pacific Community and 

WorldFish Center: Noumea, New Caledonia. 


stock restoration and enhancement. Naga – the ICLARM 


Battaglene S.C. and Bell J.D. 2004. The restocking of sea 

cucumbers in the Pacific Islands. In ‘Case studies in 

marine ranching’, ed. by D.M. Bartley and K.M. Leber.

FAO Fishery Technical Paper No. 429, 109–132. Food and 

Agricultural Organization of the United Nations: Rome. 

Brokordt K.B., Fernandez M. and Gaymer C.F. 2006. 

Domestication reduces the capacity to escape from 

predators. Journal of Experimental Marine Biology and 

Ecology 329, 11–19. 

Davis J.L.D., Eckert-Mills M.G., Young-Williams A.C., Hines 

A.H. and Zohar H. 2005. Morphological conditioning of 

hatchery-raised invertebrate Callinectes sapidus to improve 

field survivorship after release. Aquaculture 243, 147–158. 

Delgado G.A., Glazer R.A. and Stewart N.C. 2002. Predatorinduced 

behavioral and morphological plasticity in the 

tropical marine gastropod Strombus gigas. The Biological 

Bulletin 203, 112–120. 

Dumalan R.J., Juinio-Meñez M.A. and Casilagan I.L. 2009. 

Effects of sand conditioning on the growth, survival and 

burying behavior of hatchery-reared juvenile Holothuria 

scabra (Jaeger). Paper presented at the 10th National 

Symposium in Marine Science, 22–24 October 2009, 

Davao City, Philippines. 


scabra) in Vietnam. Aquaculture Extension Manual No. 

48. Southeast Asian Fisheries Development Center: 

Iloilo, Philippines. 

Edullantes C.M. and Juinio-Meñez M.A. 2009. The effects 

of seawater nutrient concentration on the growth and 

survival of juvenile sandfish Holothuria scabra. Paper 

presented at the 10th National Symposium in Marine 

Science, 22–24 October 2009, Davao City, Philippines. 







Agricultural Organization of the United Nations: Rome. 

Gamboa R. and Juinio-Meñez M.A. 2003. Pilot-testing the 

laboratory production of the sea cucumber Holothuria 

scabra (Jaeger) in the Philippines. The Philippine 

Scientist 40, 111–121. 

James B. 1999. Hatchery and culture technology for the sea 

cucumber Holothuria scabra Jaeger in India. Naga – the 

ICLARM Quarterly 22, 12–16. 

62 

James B. 2004. Captive breeding of the sea cucumber 

Holothuria scabra from India. In ‘Advances in sea 

cucumber aquaculture and management’, ed. by A. 



385–395. Food and Agricultural Organization of the 


Juinio-Meñez M.A., de Peralta G.M., Catbagan T.O. and 

Rodriguez B.D.R. 2009. Nursery production systems for 

hatchery-reared sandfish (Holothuria scabra). Poster at 

10th National Symposium in Marine Science, 22–24 

October 2009, Davao City, Philippines. 

Lovatelli A., Conand C., Purcell S., Uthicke S., Hamel 

J.-F., Mercier A. (eds) 2004. Advances in sea cucumber 

aquaculture and management. FAO Fisheries Technical 

Paper No. 463. Food and Agricultural Organization of 

the United Nations: Rome. 

Oliver M.D., MacDiarmid A.B., Stewart R.A. and Gardner 

C. 2008. Anti-predator behavior of captive-reared and 

wild juvenile spiny lobster (Jasus edwardsii). Reviews 

in Fisheries Science 16, 186–194. 








Purcell S. 2004. Criteria for release strategies and evaluating 





181–191. Food and Agricultural Organization of the 


Schagerström E. 2003. A study of juvenile Holothuria 

scabra (Jaeger) (Echinodermata) on different types of 

sediment at Bolinao, Pangasinan, Philippines. Degree 

project work, University of Kalmar, Kalmar, Sweden. 

Trinidad-Roa M.J. 1987. Beche-de-mer fishery in the 

Philippines. Naga – the ICLARM Quarterly, October 

1987, 15–17.

Small-scale hatcheries and simple technologies 

for sandfish (Holothuria scabra) production 

Ruth U. Gamboa 1*, Remie M. Aurelio 1, Daisy A. Ganad 1, 

Lance B. Concepcion 1 and Neil Angelo S. Abreo 1 

Abstract 

Sandfish (Holothuria scabra) hatchery production is currently being done at various scales across several 

continents including Australia, Maldives, Vietnam, Pacific island countries, Madagascar and the Philippines. 

Work in Mindanao in the southern Philippines, through the University of the Philippines Mindanao (UPMin), 

commenced in 2006. UPMin set up experimental hatcheries, ponds and other facilities by establishing 

partnerships with two local corporations: Alsons Corporation and JV Ayala Group of Companies. The former 

facility also has a seawater channel feeding fish ponds, which, through time, has harboured resident populations 

of sandfish. This channel became a source of broodstock, as well as a ‘conditioning area’ for sandfish 

collected from the wild. It also served as the first-stage nursery for juveniles. This paper describes low-cost 

technology for all stages of culturing H. scabra up to production of juveniles ≥10 g for release, and compares 

the cost-cutting innovations with those of published protocols. Three local modifications made by the UPMin 

project team are described here: the use of a seawater channel for broodstock and hapa; mono-algal feeding 

using Chaetoceros calcitrans; and the use of recycled or locally made materials. Broodstock can be kept 

for weeks in the channel with zero mortality, even without maintenance. In the hapas, juveniles can grow 

to 5–10 g in 1–2 months at an average survival of 84%. Chaetoceros calcitrans was bought from Alsons 

and scaled up using recycled 250-L PVC barrels. It was used as a feed until the early juvenile stage. These 

innovations yielded a best performance average of 2.2% survival to 3–5-mm juveniles. This paper attests to 

the progress and innovations made in sea cucumber research in the Philippines since H. scabra production 

was pilot-tested in the country in 2002. 

Introduction 

Sandfish (Holothuria scabra) hatchery production is 

currently being done at various scales across several 

continents: Australia, Maldives and Vietnam are doing 

large-scale for commercial production (Bowman 

2012; Duy 2012); the Pacific island countries are trialling 

small-scale production for community-managed 

sea ranching (Hair et al. 2011); Madagascar uses 

in-vitro fertilisation to obtain larvae all year round 

for their partner communities (Eeckhaut et al. 2008); 

and in the Philippines, seeds are primarily used in 

1 College of Science and Mathematics, University of the 

Philippines Mindanao, Mintal, Davao City, Philippines 


63 

pilot sites for sea ranching and grow-out (Olavides 

et al. 2011; Juinio-Meñez et al. 2012). 

Sandfish production was pilot-tested in the 

Philippines as early as 2002 (Gamboa and Menez 

2003). Work in Mindanao in the southern Philippines, 

through the University of the Philippines Mindanao 

(UPMin), commenced in 2006 when UPMin received 

funding from the Australian Centre for International 

Agricultural Research (ACIAR). A year later, financial 

support also came from the Philippine Government 

through the Department of Science and Technology – 

Philippine Council for Aquatic and Marine Resource 

Development. Neither project grant, however, provided 

any capital outlay, and UPMin did not have a coastal 

property. Thus began the quest for a research base and 

a low-cost means of adopting the technology locally.

The space and facility problems were overcome by 

establishing partnerships with two local corporations: 

Alsons Corporation, a large, intensive, commercial 

milkfish and tilapia industry with aquaculture facilities 

in Dumoy (Davao City); and JV Ayala Group of 

Companies, which owns High Ponds Resort, in Toril, 

Davao City. Alsons’ Dumoy facility accommodates 

one of our two experimental hatcheries. Within the 

compound is a seawater channel feeding the milkfish 

and tilapia ponds. This channel became the source 

as well as the ‘conditioning area’ for our broodstock, 

and served as the first-stage nursery for our juveniles. 

The High Ponds facility of the JV Ayala Group houses 

our second hatchery and experimental marine pond. 

This paper describes a low-cost technology for 

producing H. scabra comprising the following 

hatchery phases: broodstock collection; broodstock 

induction (induced spawning); larval rearing and 

early settlement; nursery, which is divided into first 

(in the hapa) and second (sand-conditioning) stages; 

and harvest of ≥10-g juveniles for release. It also 

describes micro-algal culture. 

The seawater channel 

In Dumoy, a 300-m-long man-made canal carries sea 

water from the main pipe to a dyke that feeds all the 

ponds. Water is pumped five or six times a week, with 

almost 90% daily exchange efficiency and depths of 

2–3 m. Through time, the channel has accumulated a 

natural sandy–muddy floor with its corresponding flora 

and fauna, including a population of H. scabra. The 

channel serves two other purposes for our project—as a 

natural conditioning area for broodstock collected from 

the wild and as a hapa-nursery system for juveniles. 

The hatcheries 

Two small-scale hatchery facilities were constructed, 

one each in Dumoy and High Ponds. The Dumoy 

hatchery was a 30-m 2 area located between two big 

holding tanks for tilapia fingerlings. It was basically 

a nipa-roofed structure with coco-wood posts. Sea 

water, electricity and space were all provided free 

by Alsons. At High Ponds, the 80-m 2 hatchery was 

roofed with corrugated PVC sheets and walled with 

chicken wire. In addition, a 6,000-m 2 freshwater 

earthen pond was converted to marine water for 

experimental use. The space for the hatchery, use of 

the pond and other selected amenities at High Ponds 

were free, but the project paid for electricity. 

64 

Hatchery protocols 

Broodstock collection and conditioning 

For each induction, we would use at least 38 sandfish, 

sized 130–250 g. The broodstock came from 

either the resident population in the Dumoy channel 

or our project sites (Davao del Sur and Davao 

Oriental), located 1 and 5 hours, respectively, 

from the hatchery. The animals from the sites were 

purchased through our local People’s Organisation 

groups and were individually packed in oxygenfilled 

polyethylene bags containing 1 L of sea water 

(Agudo 2006). The bags were layered inside a styrofoam 

chest box for transport. 

Wild broodstock were brought to Dumoy, where 

they were acclimatised for 1 hour by allowing the 

bags to float in a contained area in the water channel. 

Each animal was then taken out and dropped 

gently to the bottom. To avoid mixing with the canal 

residents, the wild broodstock were released at the 

seaward end of the channel. This conditioning setup 

eliminated feeding and maintenance, yet yielded 

about 99% survival. 

We believe that broodstock conditioning played a 

role in the success of the larval rearing that followed. 

For example, the collapse of a batch of larvae on one 

occasion (January 2010) may have been due to short 

(i.e. 2 days) broodstock conditioning. The successful 

batches came either from those conditioned longer or 

from the resident broodstock population. 

Induced spawning 

In earlier induction attempts, broodstock were 

brought up from the channel onto a floating cage, 

2 × 2 × 2 m and ~2 cm mesh size, where they were 

allowed to defecate for at least 24 hours. It was 

observed, however, that smaller individuals could 

squeeze out of the mesh holes, often incurring 

injury or lesions. An improved practice involves 

selecting healthy broodstock from the channel and 

holding them in a bare, flat-bottomed tank containing 

UV-treated sea water provided with mild aeration. 

After about 1 day, the gut-empty broodstock were 

rinsed with UV-treated sea water. They were divided 

into two spawning groups (Pitt and Duy 2004) for 

induction comprising the following steps (Figure 1): 

• Desiccation. The animals were transferred with 

care into a dry tank or bin and kept there for 

20 minutes.

• Conditioning in ambient water. The ‘dry’ animals 

were moved into a 70-L, 45-cm-high bin filled 

with 10 cm of filtered sea water, and kept there 

for 15 minutes. 

• Thermal shock. The water temperature in the tank 

was raised 3–5 °C above ambient by slowly adding 

boiled sea water (James et al. 1994). Induction 

proceeded for 1 hour. 

• Spirulina bath. Fifteen grams of Spirulina were 

mixed with 1 L of fresh water then blended well 

and added slowly to the tank. Induction proceeded 

for 1 hour. 

• Complete water change. The Spirulina was flushed 

out by using a hose siphon. Ambient sea water was 

then slowly added up to about 25 cm depth. After 

several minutes, one or two individuals would 

stand and exhibit swaying behaviour. These are 

signs of readiness to spawn—the gonopore on 

the dorsal surface of the head begins to swell; 

males release a long thread of milky sperm, while 

females release yellowish eggs in two to four 

bursts that usually shoot out of the water. 

65 

Gametes were collected using a beaker. Sperm 

were scooped out of the water and eggs were collected 

from each spawning individual by following 

the direction of the swaying female and positioning 

the beaker accordingly. Since the released eggs usually 

shoot out of the water, collecting them required 

some practice. All sperm were mixed together in a 

70-L container, and all eggs in a 20-L container. 

To estimate the total egg count, the eggs were 

pooled in 40 L of sea water. Three subsamples of 

1 mL each were taken and counted under a microscope. 

The average of the three counts was computed. 

The total number of eggs was roughly estimated 

using equation (1): 

Total egg count = average count/mL 

(1) 

× 40,000 mL 

About 0.5 mL of sperm from the mixture was 

introduced to the 40-L egg stock. Too much sperm 

can lead to polyspermy. Two-cell stage could be 

observed within the next few hours. 

Figure 1. Induction of Holothuria scabra. Upper row: desiccation (left), thermal shock (centre), Spirulina bath 

(right); lower row: spawning male (left) and female (right)

Regardless of the length of conditioning of 

the broodstock in the water channel, the thermal- 

Spirulina shock (Agudo 2006) proved effective in 

9 of our 10 inductions. A summary of the hatchery 

performance from those successful inductions is 

shown in Table 1. The single instance when the 

thermal-Spirulina shock did not work was with 

broodstock that came from the project site and were 

induced the next day. 

Our spawning induction trials were carried out 

randomly (during any month) based on the available 

free tanks in the hatcheries. The success of induction 

alone did not follow any lunar phase, as was also 

observed by Pitt and Duy (2004). In all nine trials, 

the males spawned first, which was in keeping with 

the reports of other authors (Agudo 2006; Duy 2010; 

Giraspy and Ivy 2010; Pitt et al. 2001). 

Larval rearing 

Larval density 

We used a low density of 0.3 fertilised eggs/mL, 

calculated as (equation (2)): 

Number of larvae per tank = desired volume 

(2) 

of water in tank × 0.3 fertilised eggs/mL 

The volume of fertilised eggs to be used (equation 

(3)) was: 

Volume of 

fertilised eggs = 

0.3 eggs/mL 

× total volume of 

fertilised eggs 

Average count/mL in 

the 40 L concentrate 

(3) 

Rearing tanks 

Our 250-L conical-bottom larval rearing tanks 

were made of marine plywood and custom built to 

fit the hatchery area. The larval tanks were prepared 

for stocking by washing them well with chlorine, 

rinsing with fresh water and then air-drying. Next, 

each tank was half-filled with 1-µm filtered and 

UV-treated sea water. The fertilised eggs were then 

poured in gently and water was brought to the desired 

volume. Moderate aeration was applied on the first 

day of rearing. 

Rearing tanks were completely covered during the 

larval stages using thin white cloth overlain with black 

cellophane bags. This kept the larvae in darkness and 

also prevented chironomid (bloodworm) infestation. 

66 

A week after the appearance of pentactula, the black 

cellophane was removed to allow light to penetrate 

the tank and encourage moderate algal growth for the 

juveniles. This differs from Agudo’s (2006) protocol, 

where the tank is covered for only the first 2 days of 

larval rearing. We noted that algal growth was better 

on tank walls that were not very smooth. 

Water monitoring and larval sampling 

Temperature and salinity were monitored daily. 

Temperatures varied in the range 26–29°C, while 

salinity was 30–34 ppt. The density of larvae was 

estimated by counting in a known volume of test 

tube or glass tubing viewed against the light. 

Developmental stages of larvae were monitored 

under the microscope. 

Water treatment and water change 

Sea water for the larval tanks went through three 

filtrations: UV light, 10-µm and 1-µm tube filters, and 

a 1-µm bag filter. Thirty per cent of the water volume 

was changed daily. To chelate heavy metal residues, 

we added ethylenediaminetetraacetic acid (EDTA) 

at 5 g/m 3 per total volume of water changed. When 

larvae were no longer present in the column, EDTA 

treatment was halted and water change was done 

every other day until all juveniles were ready for the 

hapas. By 2010 we ceased chelating with EDTA and 

yet our survival rates were improving. During the June 

and October 2010 batches, the UV light in the Dumoy 

hatchery broke. We proceeded with the rearing using 

filtered sea water only. Since survival of juveniles was 

among the highest in these batches, it appears that UV 

light and EDTA can be eliminated. 

Larval food and feeding regime 

Feeding the larvae started on day 2. Our protocol 

used just one species, Chaetoceros calcitrans, 

throughout—the regime is shown in Table 2. 

Chaetoceros spp. are some of the best algae for larval 

rearing (Battaglene 1999). We initially adopted a 

once-a-day feeding regime with C. calcitrans until 

Mr Duy (Vietnam) suggested splitting the ration at 

9 am and 3 pm. This strategy improved the survival 

rate of our June and October 2010 batches (Table 1). 

Feeding was thereafter done twice a day until the 

juveniles were moved out into the hapas. In his seed 

production manual, Duy (2010) prefers a mixture 

of algae for optimal growth, and recommends the 

single species only when there is not enough algal 

supply. We found single feeding with Chaetoceros

Table 1. Summary of combined production performance of the Dumoy and High Ponds hatcheries 

Remarks 

Count and 

% survival 

of 3-mm 

juveniles 

EDTAb Initial 

fertilised 

eggs in 

tanks 

Total 

fertilised 

eggs 

(millions) 

Minutes 

after the first 

spawnera Count of 

spawners 

Total 

broodstock source, 

conditioning 

Days after moon 

phase 

Batch date 

M F M F 

38, Dumoy channel residents 12 14 40 55 2.4 No 240,000 5,400 Hapa by day 38 

(2.2%) 


(1.8%) 

38, Dumoy channel residents 4 5 20 0 1.28 No 180,000 300 Collapsed by day 34 

(0.2%) 


(1.5%) 

40 from wild; conditioned in 10 21 30 11 2.6 No 180,000 0 Collapsed by day 6; 

Dumoy channel for 2 days 

short (2-day) 

conditioning period 

47 from wild; conditioned in 12 20 29 15 1.9 Yes 400,000 539 Collapsed by day 43; 


(0.13%) heavily infested with 

bloodworms 

46 from wild; conditioned in 14 23 25 51 6.8 Yes 300,000 71 Collapsed by day 39; 


(0.02%) heavily infested with 

bloodworms 

40 from wild; conditioned in 12 13 30 12 2.7 No 300,000 0 Collapsed by day 20; 


heavily infested with 

bloodworms 

43 from wild; conditioned in 15 16 36 12 4.3 No 300,000 2,500 Hapa by day 38 

Dumoy channel for more than 

(0.83%) 

1 week 

1 day after F.Q. 

15 October 2010 

4 days after F.Q. 

23 June 2010 


23 February 2010 

5 days after L.Q. 

11 February 2010 


13 January 2010 

(High Ponds only) 

2 days after F.M. 

4 December 2009 

67 


6 October 2009 

6 days after F.M. 

13 July 2009 


6 May 2009 

a Always a male 

b EDTA = ethylenediaminetetraacetic acid 

F.Q. = first quarter; L.Q. = last quarter; F.M. = full moon

was sufficient, simple and cost-effective. Our best 

performance was 2.2% survival from fertilised eggs 

to 3-mm juvenile stage. 

Settlement plates 

Settlement plates were made of corrugated 

polyethylene roof materials that were cut into pieces 

about 350 × 200 mm. The long sides of each piece 

were tied together midway with a nylon string to 

assume a partial fold that could be stacked randomly 

at the bottom of the tank. 

Each piece was washed with detergent and chlorine 

and air-dried, making sure to keep off insects 

that might lay eggs on the plates. The rough side was 

painted with a thin coat of Spirulina paste prepared 

by diluting the powder with just enough water to create 

a paste-like consistency (Duy 2010). The plates 

were added once doliolaria were observed, and were 

stacked randomly in the tanks up to 50% of the water 

column. The water was changed 3 hours after adding 

the plates or until all the Spirulina bubbles were 

eliminated. Strong aeration was provided. 

68 

Rearing problems 

Infestation of chironomids and copepods, both in 

the tanks and on settlement plates, was the main cause 

of low survival or population crashes in our hatcheries. 

In four of the five crashes, the white cloth tank 

covers were removed at settlement stage. These tanks 

showed severe chironomid infestation. We decided to 

keep the cover on until harvest time at ≥3 mm, and 

this improved the survival rate. Chironomids at the 

High Ponds site were more difficult to control, probably 

due to the shaded location of the hatchery and the 

presence of more trees in the immediate surroundings. 

The hatchery in Dumoy, on the other hand, is sandwiched 

between two concrete structures (Figure 2). 

We found that copepods can survive even in 

UV-treated and filtered seawater systems, as was also 

reported by Pitt and Duy (2004). They can destroy 

good batches of settled juveniles within a few days. 

To address this, proper aseptic procedures were 

observed, such as chlorination of water pipes and 

tanks before and after each batch, and covering the 

Table 2. Daily feeding concentration of Chaetoceros calcitrans used for Holothuria scabra production in this 

protocol 

Day from fertilisation Larval stage Chaetoceros cells/mL Aeration 

2 Early auricularia 20,000 gentle 

4 Mid auricularia 20,000–25,000 moderate 

6 Mid and late auricularia 25,000–30,000 moderate 

8 Late auricularia 30,000–40,000 moderate 

10 

(till transfer to hapa) 

Doliolaria 

(till 0.5-mm juvenile) 

30,000–40,000 strong 

(once plates are added) 

Figure 2. The hatchery at High Ponds, Toril (left) is shaded by trees on one side and at the back, while that in 

Alsons, Dumoy (right), is more exposed to sunlight.

tanks immediately after water change. Our staff were 

told to be mindful of being carriers of contaminants. 

For example, they had to rinse their hands before 

doing tank water changes, especially if they had come 

directly from monitoring the hapas in the channel. 

Agudo (2006) recommends thorough rinsing of all 

rearing materials with freshwater before and after use, 

and storing them in containers with chlorinated water. 

Nursery 

First phase: ≥3-mm juveniles into hapas 

In our experience, juveniles do not grow uniformly 

in the tanks. This is still a difficulty in our optimisation 

of a low-cost technology, although significant 

improvement in the rate of survival to 3 mm was 

obtained when the feeding regime was split into 

two, tanks were fully covered to prevent chironomid 

infestation, and rough inner surface tanks and rough 

settlement plates were used. 

By day 38, a good number of juveniles had reached 

≥3 mm in size. This group was harvested and moved 

into the hapas. Harvesting involved using a fine, soft 

watercolor paintbrush to detach the bigger juveniles 

Table 3. Survival of juveniles in the hapas inside the seawater channel at Dumoy 

Batch / date Total count 

of 3–5-mm 

juveniles 

Total hapas (@ 

400 juveniles per 

hapa) 

69 

from the plates. After harvesting, those plates still 

with smaller juveniles were dropped back into the 

tanks without repainting with Spirulina. A thin film 

of algae could regrow on the plates overnight. With 

this thinning-out process, juveniles were harvested at 

least three times within a 3–7-day interval. 

The hapas, measuring 1 × 2 × 1 m with a mesh size 

~1 mm, were made of the same material as that used 

by local pond operators. Because the water level in 

the channel changes regularly, floating hapas were 

designed (Figure 3). The four surface corners of 

the hapa were tied to bamboo poles fixed to paddle 

wheel buoys; and the bottom corners and the middle 

floor were fastened with weights to keep the floor 

submerged in the water all the time. The hapas were 

conditioned for 3–5 days to allow a substantial mat of 

biofilm to grow. Then 400 juveniles (≥3 mm length) 

were transferred into them (Figure 4). The algal mat 

served as natural food for the growing juveniles and 

eliminated the manual task of feeding them. In the 

channel, growth of biofilm is fast and periodic thinning 

was done by gently scrubbing the outer sides of 

the hapa. In Vietnam the hapas are tied to bamboo 

poles that are fixed on the substrate of the pond. The 

Figure 3. The seawater channel at Alsons, Dumoy (left), and the floating hapas (right) 

Mean wet weight (g) 

after 30 days 

Count and % survival 

after 30 days 

15 October 2010 5,400 14 5.45 3,051 (56.5%) 

23 June 2010 6,400 16 2.5 2,717 (42%) 

11 February 2010 4,000 10 3.5 3,822 (96%) 

6 May 2009 2,000 5 2.1 1,453 (73%)

Figure 4. Harvesting ≥3-mm juveniles from a plate (left); releasing the juveniles onto a hapa (centre); 1-monthold 

juveniles in the hapa (right). A synaptid (foreground) and seahare egg case (tip of caliper) are seen 

with the juveniles. 

water level in their ponds follows the natural high- 

and low-tide cycle, but growth of biofilm is not as 

thick as that in the Dumoy water channel. 

A summary of the survival rates of juveniles in the 

hapas is shown in Table 3. Our best record was 96%. 

Low survival in June and October 2010 occurred when 

juveniles were kept in hapas longer than 35 days. As in 

the tanks, juveniles in the hapas do not grow uniformly, 

and harvesting was also done two to three times. The 

first harvest was conducted at 30–35 days, and juveniles 

≥2.0 g were thinned out. One to two more batches 

of late shooters would catch up at 2–3-week intervals. 

Longer time in the hapa and frequent handling 

seemed unfavourable for the juveniles. This staggered 

harvesting can be a natural pacing for grow-out or searanching 

releases. It should be well managed in order 

to avoid a glut at the nursery and ensure continuous 

release and, consequently, continuous harvest. 

Predators in ocean nurseries include crabs and 

carnivorous fishes (Dance et al. 2003; Lavitra et al. 

2009). Surprisingly, they were not a problem in the 

water channel. Although synaptids and Dollabella 

(Figure 4) were common invaders, we noted no 

threats to the growing juveniles. The weights in the 

bottom corners of the hapas have to be checked regularly—without 

them the floor rises up to the surface 

and could expose the juveniles to more direct heat 

from the sun and warmer water temperature. 

Second phase: sand-conditioning of ≥2.0-g 

juveniles 

Juveniles ≥2.0 g were conditioned in the substrate 

before they were released for grow-out or sea 

70 

ranching. We conducted several pond experiments 

using various sized juveniles from the hapas. In 

one of the trials, three pens (3 × 5 × 0.4 m each, 

made of PVC screen, with a mesh size of 15 mm) 

were laid out in one portion of the pond. To each 

pen, 50 juveniles (3–13 g) were introduced. After 

the first month, the average wet weight was 21.3 g 

(i.e. growth rate of 0.77 g/day) (Figure 5). After 4 

months, the survival rate was 70–100%, with an 

average wet weight of 191 g. In another experiment 

involving smaller juveniles, survival after a month 

was 58–80% and average growth rate was 0.42 g/day. 

While growth and survival of juveniles varied, the 

marine pond proved, at the very least, to be a reliable 

juvenile sand-conditioning area. 

In Vietnam H. scabra are commercially grown to 

≥500 g in marine ponds. The ponds are converted 

shrimp ponds and are irrigated by natural rise and fall 

of the tides. In the Philippines there are also many 

abandoned shrimp farms, and their potential for 

sea cucumber grow-out is recommended for further 

investigation. 

Harvest of ≥10-g juveniles for release 

We recommend ≥10 g for release size, as the bigger 

the juvenile, the greater the chances of survival, 

especially in sea ranches. Juveniles were packed in 

groups of five in oxygen-filled polyethylene bags 

containing 1 L of sea water, and transported to the 

release site in the same way that broodstock are 

transported. On site, the bags were allowed to float 

on the water for about 30 minutes to acclimatise the 

juveniles to the ambient temperature (Figure 6).

Average wet weight (g) 

350 

300 

250 

200 

150 

100 

50 

0 

n = 50 

juveniles/pen 

Initial 

Pen 1 

Pen 2 

Pen 3 

Figure 5. Growth of juveniles in pens within a marine pond in High Ponds. Vertical bars represent 

standard error while numbers inside bars in month 4 represent the surviving individuals. 

Chaetoceros culture 

A significant reduction in production cost in terms 

of labour and raw materials was achieved by using 

a single-species feed, Chaetoceros calcitrans, for 

the larvae. This regime was adopted from practices 

in Vietnam. Every week, 1 L of stock culture was 

brought in by Alsons from their algal laboratory in 

another city. Using the formulation of Agudo (2006), 

the stock was scaled up to 10 L inside an air-conditioned 

algal room (Figure 7; refer also to appendix). 

Sea water for culture passed through UV-sterilisation, 

microfiltration and chlorination–dechlorination. These 

10-L stocks in turn became the seed for outdoor 

upscaling in 250-L recycled PVC drums. Another 

suspected source of chironomids was the scaled-up 

Month 1 Month 2 Month 3 Month 4 

Figure 6. Transporting the juveniles to site of release—community partners at work 

71 

Chaetoceros cultures. It was necessary to bring the 

drums out in the open for exposure to sunlight, but 

they were tightly covered with thin, white cloth to 

prevent chironomid infestation. 

Conclusions 

35 47 50 

The cost-cutting innovations in this paper are 

compared with those of Agudo’s (2006) protocol 

(Figure 8). Protocols to produce sandfish are already 

established, and H. scabra has been found to grow in 

various systems (James et al. 1994; Battaglene et al. 

1999; Gamboa et al. 2004; Pitt and Duy 2004; Agudo 

2006; Duy 2010). Three local modifications made by 

the Mindanao project team have been described here: 

mono-algal feeding using Chaetoceros calcitrans; the

Figure 7. The algal room (left); some Chaetoceros calcitrans jugs inside (centre); outdoor upscaling making use 

of recycled glucose syrup barrels (right) 

Agudo’s protocol 

• Conditioning tanks 

• Flow-through system 

• Aeration, feeding 

• At least two algal food 

species during planktonic 

stage 

• Water change from 30% 

daily to 100% every 

other day 

• EDTA after water change 

• Two diatom species and 

supplement feeding and 

fertiliser at settlement 

stage 

• 12-hour photoperiod 

(tanks uncovered) 

• Nursery tanks with 

flow-through water 

• Hapas made of 

expensive material 

• Tanks for substrate 

conditioning 

Broodstock collection 

and conditioning 

Spawning induction 

(thermal and Spirulina shocks) 

Fertilisation and stocking of eggs 

Rearing of auricularia 

Rearing of doliolaria 

Settlement of pentactula 

Release to hapas 

(1st stage nursery) 

Substrate conditioning 

(2nd stage nursery) 

Release to sea ranch/pond 

Figure 8. Comparison of cost-cutting innovations in this paper with those 

of Agudo’s (2006) protocol 

72 

This paper’s 

cost-cutting methods 

• Use of the water channel 

No tanks, no feeding, no 

aeration, no flow through 

• One feeding regime with 

Chaetoceros calcitrans only; 

savings on electricity, water, 

reagents, labour 

• Feeding twice a day 

• Water change, 30% daily 

• Tanks covered with black 

cloth to keep light and 

chironomids out 

• One feeding regime with 

Chaetoceros calcitrans only 

• Water change, 30% every 

other day 

• Tanks covered with white 

cloths 

Best record: 2.2% survival to 3 mm 

• Hapa made of local material, 

set up in a water channel 

• Low maintenance: no feeding, 

no aeration, no water change 

1-month average: 84.5% survival 

to 3–5 g 

• In pens inside earthen pond 

• Low maintenance: no feeding, 

no aeration, no water change 

1-month average: 66% survival to 

21.34 g

use of a seawater channel for broodstock conditioning 

and hapa nursery; and use of recycled or locally 

made materials. These modifications were made in 

the context of partnership: the mono-algal feeding 

was adopted from the system employed by Mr Duy 

in RIA3, Nha Trang, Vietnam; and the water channel, 

marine pond and hatchery spaces were provided by 

two private partners, Alsons Corporation and the 

JV Ayala Group of companies. This paper attests to 

the progress and innovations made in sea cucumber 

research in the Philippines since H. scabra production 

was pilot-tested in Bolinao in 2002 (Gamboa and 

Juinio-Menez 2003). 

References 




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1999, Heriot-Watt University, Kuala Lumpur, Malaysia. 




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of sea ranching in northern Australia. In ‘Asia–Pacific 





Dance S.K., Lane I. and Bell J.D. 2003. Variation in shortterm 

survival of cultured sandfish (Holothuria scabra) 

released in mangrove-seagrass and coral reef flat habitats 

in Solomon Islands. Aquaculture 220, 495–505. 



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pond culture in Vietnam. In ‘Asia–Pacific tropical 





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M.W., Gildas P. and Jangoux M. 2008. Madagascar 

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Gamboa R. and Juinio-Menez M.A. 2003. Pilot-testing the 

laboratory production of the sea cucumber Holothuria 

scabra (Jaeger) in the Philippines. The Philippine 

Scientist 40, 111–121. 

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of the tropical sea cucumbers Holothuria scabra and H. 

lessoni in the Indo-Pacific region. SPC Beche-de-mer 





James D.B., Gandhi A.D., Palaniswamy N. and Rodrigo 

J.X. 1994. Hatchery and culture of the sea-cucumber 


Institute Special Publication No. 57. 


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(Holothuria scabra) sea ranching in the Philippines. In 

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by C.A. Hair, T.D. Pickering and D.J. Mills. ACIAR 



proceedings] 

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I. 2009. Problems related to the farming of Holothuria 

scabra (Jaeger, 1833). SPC Beche-de-mer Information 


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Preliminary sandfish growth trials in tanks, ponds, 


Bulletin 15, 17–27.

Appendix. Modified Chaetoceros upscaling formulation 

The technology in this paper does not maintain an 

algal culture. Instead, a 4 L stock of Chaetoceros 

is purchased from Alsons every other week and 

scaled up outdoors in the hatchery using recycled 

polyethylene barrels. The formulation we modified 

is described here and is not intended for maintaining 

pure stock cultures. 

Chlorination–dechlorination 

12.5% chlorine strength stock solution. Usage: 

0.2 mL (stock) per litre of culture volume (Agudo 

2006). Although chlorine content is not indicated in 

sodium hypochlorite powder, for calculation purposes 

we estimated the strength to be around 70%, based on 

references on the internet about sodium hypochlorite 

available in the Asian market. 

74 

250 g thiosulphate in 1-L solution to make stock 

solution. Usage: 0.2 mL (stock) per litre of culture 

volume (Agudo 2006). 

Chaetoceros upscaling formulation 

(modified from Agudo 2006) 

1. Fertiliser—Manusol (30:10:10): for 10-L jug 

culture, 0.25 g is needed; for 200-L culture, 5 g 

is needed 

2. Silicate—sodium metasilicate: for 10-L jug culture, 

0.375 g is needed; for 200-L culture, 7.5 g 

is needed.

Sandfish production and development of 

sea ranching in northern Australia 

William M. Bowman 1* 

Abstract 

Sea cucumber harvesting has been carried out in the Northern Territory (NT) since 1700 when Macassans 

regularly visited the area. Tasmanian Seafoods Pty Ltd currently holds all licences for sea cucumber in the NT, 

with the main target species being sandfish (Holothuria scabra). Tasmanian Seafoods has successfully trialled 

propagation and juvenile production for wild fishery stock enhancement and land-based grow-out in ponds. 

Lease of an ex-prawn farm and hatchery facilities at Darwin Aquaculture Centre has progressed its efforts. 

Tasmanians Seafoods has established working relationships with remote Indigenous communities situated nearby 

on recognised fishing grounds on Groote Eylandt, to develop the sea-ranching component of the project and 

establish joint ventures for the harvesting of the ‘released’ sea cucumbers. Appropriate policies and management 

arrangements are also being negotiated with the NT Government Department of Resources Fisheries Group. 

Introduction 

Sea cucumber harvesting has been carried out in the 

Northern Territory (NT) since 1700, when Macassans 

from Celeb (Sulawesi island group, Indonesia) visited 

annually and set up processing sites adjacent to the 

fishing grounds (Macknight 1976). The industry 

has evolved and now consists of a series of regulatory 

controls to manage the fishery, predominantly 

through input controls. Entry to the fishery is limited 

to six licences that are restricted by area, species, 

minimum size and the number of divers on each 

vessel (Shelley and Puig 2003). 

Tasmanian Seafoods Pty Ltd is currently the sole 

licence owner for sea cucumber fishing in the NT. 

The fishery’s principle target species is the sandfish 

(Holothuria scabra). Since 2004 Tasmanian Seafoods 

has been investigating the potential of propagation 

and juvenile production of sandfish, with a view 

to enhancing the existing wild fishery through sea 

ranching and exploring land-based grow-out. 

1 Tasmanian Seafoods Pty Ltd, Darwin, Australia 


75 

During 2006–08, repeated trials were carried out 

to assess the potential of land-based grow-out and 

develop pond-management techniques for H. scabra. 

Promising results led to the expansion of the project 

by leasing a farm that had previously been used to 

cultivate prawns. Subsequently, a ‘farming’ component 

was added to the sea-ranching project, enabling 

greater access to, and utilisation of, necessary facilities 

(e.g. earthen ponds) for the project. 

In developing the sea-ranching component of 

the project, Tasmanians Seafoods has sought to 

create effective working relationships with remote 

Indigenous communities situated nearby on recognised 

fishing grounds, and establish joint ventures for 

the harvesting of the ‘released’ sandfish. The development 

of sea ranching has also required ongoing 

negotiations with the NT Government Department 

of Resources Fisheries Group to develop appropriate 

policies and management arrangements to conform 

with the NT’s Fisheries Act 1998. 

The fishery 

The fishing grounds occur along the Arnhem 

Land coast, with the major harvest areas being the

Cobourg Peninsula and Groote Eylandt (Figure 1) 

(Handley 2010). All commercial harvesting of sea 

cucumber in the NT is conducted by hand, either by 

walking the shallows, snorkelling or hookah. The 

fishery operates in waters up to 3 nautical miles 

seaward of the NT and surrounding islands coast. 

The hatchery 

In 2004 Tasmanian Seafoods set up a pilot hatchery 

at the NT Government’s Darwin Aquaculture Centre 

(DAC). Initially, the hatchery was dependent on 

wild caught broodstock, which proved restrictive 

due to the logistics of acquiring broodstock from the 

fishing grounds, with the nearest grounds being on 

the Cobourg Peninsula about 200 km away with no 

road access (Figure 1). This led to the development 

of transport techniques using vessels and aircraft to 

collect and transfer broodstock to the hatchery with 

minimal stress, and the lease of ponds at a local 

aquaculture farm to hold breeding stock. 

Successful larval culture of H. scabra led to 

expansion of the hatchery at the DAC. The larval 

rearing infrastructure is now a recirculating system 

comprising a 25,000-L sump, 40,000-L larval rearing 

volume, 36,000-L conditioning system and two 

1,500-L experimental larval rearing systems. 

All sea water entering the system has a salinity 

of 30‰ and is filtered to 1 µm. Once in the loop, 

Cobourg Peninsula 

Darwin 

Northern Territory 

500 km 

76 

the water is repeatedly treated with UV sterilisation 

and foam fractionation. The hatchery is located in a 

covered outdoor area, and water temperature in the 

larval rearing tanks is in the range 27–31 °C. 

During the larval run, the larval tanks are static 

with a daily partial water exchange. The larvae are 

predominantly fed Chaetoceros muelleri, beginning 

at densities of 15,000 cells/mL and increasing to 

35,000 cells/mL by the end of the run. Once the 

larvae have settled, the tanks are put on flow-through 

at 100% water exchange per day. 

The conditioning tanks are used to cover settlement 

substrates with diatoms, with a good coverage 

of periphytic diatoms on our settlement substrates 

generally taking around 5–7 days. Settlement 

substrates are then put into the larval tanks at the 

time of settlement, to help induce the larvae to settle 

and provide food for the post-settlement and early 

juvenile stages. While larval settlement is consistently 

achieved, the settlement rate is highly variable 

between tanks, often ranging from 0.4% to over 20%. 

The larval tanks are harvested and graded soon after 

settlement, generally at around day 30. 

The ponds 

Tasmanian Seafoods secured the lease on a prawn 

farm in 2009. The facility comprises eight 1-ha 

ponds, six 0.1-ha ponds, and one 2-ha reservoir. The 

Arnhem Land 

Groote Eylandt 

Figure 1. Major harvest areas of the Northern Territory (Australia) sea cucumber fishery

1-ha ponds are used for production, currently yielding 

2.0–2.5 tonnes wet weight per hectare. The 0.1-ha 

ponds are more versatile and easily managed, and are 

used for broodstock holding and conditioning, and 

nursery production. 

Water is pumped from Darwin Harbour into the 

reservoir, which then gravity-feeds the rest of the 

farm. The ponds are on flow-through, and water 

quality is regularly monitored. Between February 

2010 and January 2011, the salinity in the reservoir 

ranged from 24.6‰ to 38.6‰, and the temperature 

ranged from 24.7 °C to 35.2 °C. Optimal dissolved 

oxygen levels are maintained by using air diffusers 

mounted on the bottom of the ponds connected to air 

blowers. The diffusers also vertically mix the water 

column, preventing stratification. 

The pond nursery system currently consists of 

30 hapa nets (2.5 × 2.5 m, 1-mm mesh), which are 

stocked with newly settled juveniles (>1 mm). The 

grow-out ponds are stocked when juveniles reach 

25 mm (Figure 2). The growth rates in ponds increase 

with animal size, and with suitable conditions can 

exceed 2.5 g/day when animals are nearing harvest 

(i.e. around 350 g). Freshwater influx into the ponds 

through the monsoon season is managed by adjusting 

Figure 2. Nursery production of sandfish 

77 

flow-through rates; and pond depth is maintained 

using boards or internal standpipes, giving the ability 

to skim the fresh water off the top. 

Sea ranching 

In 2006 Tasmanian Seafoods began searching for 

suitable sites to conduct sea-ranching trials. Little 

Lagoon on Groote Eylandt (Figure 3) was chosen 

due to the presence of suitable release habitat for 

hatchery-produced juveniles. In addition, the local 

community of Umbakumba expressed an interest in 

being involved in the project. 

Little Lagoon is a shallow basin approximately 

2,000 ha in area comprising patches of seagrass, 

shifting sand bars and mud substrate. The area has 

long been recognised as a productive fishery and 

natural nursery area for sandfish (R. Hone, pers. 

comm., 2009). The lagoon also has favourable geographical 

characteristics for monitoring the released 

sandfish, including protection from the weather due 

to its semi-enclosed nature and a low tidal range, 

which helps to maintain good water visibility. 

Building a successful relationship with the 

Umbakumba community has been critical for the

developmental stage of the sea-ranching project. 

There are obvious logistical difficulties associated 

with this site, which is approximately 700 km from 

the hatchery. However, local community involvement 

allows for relatively simple management of the project, 

while regular barge and plane services facilitate 

transport of equipment to and from the site. 

Future direction 

Groote Eylandt 

10 km 

Figure 3. Location of sea-ranching site, Little Lagoon, Groote Eylandt 

The future direction for Tasmanian Seafoods in sea 

cucumber propagation and sea-ranching research is 

to increase hatchery and nursery efficiency through 

improved hatchery protocols and system design; 

improve pond management to reduce variation and 

increase yields; and accurately assess the viability of 

sea-based grow-out of sandfish. 

Tasmanian Seafoods aims to promote Indigenous 

community involvement in sea ranching in the NT, 

creating opportunities and economic activity in 

remote areas. Information generated in the research 

will assist in determining the potential of stock 

enhancement as a management tool for the future 

development and sustainable use of the NT’s sea 

cucumber fishery. 

78 

Umbakumba 

Little 

Lagoon 

References 

Handley A.J. (ed.) 2010. Fishery status reports 2009. 

Northern Territory Government Department of 

Resources. Fishery Report No. 104, 113–119. 

Macknight C.C. 1976. The voyage to Marege: Macassan 

trepangers in northern Australia. Melbourne University 

Press. 

Shelley C.C. and Puig P. 2003. Management of sea 

cucumbers in the Northern Territory, Australia, and 

current research to further improve understanding of the 

fishery. In ‘Advances in sea cucumber aquaculture and 

management’, ed. by A. Lovatelli, C. Conand, S. Purcell, 

S. Uthicke, J.-F. Hamel and A. Mercier. FAO Fisheries 



Hatchery experience and useful lessons from 

Isostichopus fuscus in Ecuador and Mexico 

Annie Mercier 1*, Roberto H. Ycaza 2, Ramon Espinoza 3, 

Victor M. Arriaga Haro 4 and Jean-François Hamel 5 

Abstract 

This paper summarises lessons learned from captive breeding of the sea cucumber Isostichopus fuscus in 

land-based installations on the coast of Ecuador and Mexico. This species has been intensively fished in 

Mexico, along mainland Ecuador and around the Galapagos Islands. Management efforts have traditionally 

been challenged by local economic and social conditions. Populations of I. fuscus have thus been severely 

depleted over the past decades, generating interest in aquaculture and restocking. Spawning, fertilisation, 

larval rearing, disease control and juvenile growth have been documented in two privately owned hatcheries. 

Data from trials conducted in Ecuador over several years indicate that, under optimal conditions, juveniles 

can be grown to a size of ~8 cm in length in 3.5 months and to commercial size in ~18 months. Preliminary 

tests have shown that growing juvenile sea cucumbers in shrimp ponds is feasible. In Mexico, successful 

spawnings were restricted to late summer and autumn/fall months, when cultures of larvae and early juveniles 

yielded growth rates similar to or greater than those recorded in Ecuador. Grow-out of juveniles in shrimp 

ponds was impeded in both countries by skin infections, leading to high mortality rates, whereas juveniles 

placed in cages in the ocean (in Mexico) exhibited reasonable growth rates and better survival (to 90%). 

Overall, studies demonstrate that, with proper disease control, millions of juvenile I. fuscus can be reared in 

captivity annually, thus providing an alternative to fisheries, or a way to maintain sustainable harvests and 

eventually contribute to restoration of the natural populations. 

Introduction 

Isostichopus fuscus (Figure 1) is a deposit-feeding 

sea cucumber that is mainly found on reefs and sandy 

bottoms along the western coast of the Americas, 

from northern Peru to Baja California, Mexico 

(Castro 1993; Toral-Granda 1996; Sonnenholzner 

1997; Gutierrez-Garcia 1999). Like many other 

1 Ocean Sciences Centre (OSC), Memorial University, St 

John’s, Newfoundland and Labrador, Canada 


2 Investigaciones Especies Acuaticas (IEA), Santa Elena, 

Ecuador 

3 Acuacultura dos Mil S.A. de C.V., Mazatlán, Sinaloa, Mexico 

4 Organización y Fomento de la Comisión Nacional de 

Acuacultura y Pesca, Mazatlán, Mexico 

5 Society for the Exploration and Valuing of the Environment 

(SEVE), St Philip’s, Newfoundland and Labrador, Canada 

79 

commercial sea cucumber species, I. fuscus has been 

widely fished over past decades to meet the growing 

demand for beche-de-mer in the major Asian markets. 

As the waters along mainland Ecuador became 

depleted, the fisheries shifted to the Galapagos 

Islands in the early 1990s, raising international 

apprehension over the fate of this unique archipelago, 

which has been recognised as a national park and 

marine reserve. Since then, attempts by government 

at regulating sea cucumber harvests, and banning 

them in some areas, have met strong opposition 

from local fishers in Ecuador. In fact, illegal fisheries 

have always been a concern and still occur along 

the mainland coast, around the Galapagos Islands 

and elsewhere in the distribution area of I. fuscus. 

In 1994 the Government of Mexico imposed a total 

closure because this species was considered locally 

endangered. However, the closure was not obeyed by

Figure 1. Adults of Isostichopus fuscus photographed (A) in situ (Galapagos Islands) 

and (B) in land-based installations (mainland Ecuador) showing the main 

colour morphs 

fishers, leading to a decrease in the biomass, which is 

now only 2% of the original biomass in some regions 

(Castro 1995; Aguilar-Ibarra and Martinez-Soberon 

2002). Currently, the fishery in Mexico is managed 

under concessions and stricter activity controls 

(Toral-Granda 2008). 

Official information on the fisheries and actual 

total catches are difficult to obtain and remain sparse 

(Salgado-Castro 1993; Castro 1997; Sonnenholzner 

1997; Gutierrez-Garcia 1999; Jenkins and Mulliken 

1999). Nevertheless, recent data and reports 

on average capture sizes (Sonnenholzner 1997; 

Martinez 2001) indicate that I. fuscus populations 

have declined substantially and that natural stocks 

may irreversibly crash in the near future. Stock 

recovery has yet to be observed in any region 

(Toral-Granda 2008). 

Despite this situation, a very limited number of 

studies has been conducted on the reproductive biology, 

spatial distribution, population structure, growth 

and survival rate of I. fuscus (Herrero-Pérezrul 

1994; Fajardo-Leon et al. 1995; Toral-Granda 1996; 

Sonnenholzner 1997; Herrero-Pérezrul et al. 1999; 

Hamel et al. 2003; Mercier et al. 2004, 2007; Toral- 

Granda and Martínez 2007; Becker et al. 2009). 

Some authors have mentioned that aquaculture and 

restocking should be investigated as possible solutions 

to the current crisis (Gutierrez-Garcia 1995, 

1999; Fajardo-Leon and Velez-Barajas 1996; Jenkins 

and Mulliken 1999). 

Until recently, aquaculture in Ecuador and Mexico 

was largely focused on shrimp. The emergence of 

white spot disease in 1999–2000 has severely 

affected the industry and resulted in the bankruptcy 

and closure of numerous farms. Consequently, 

both countries now have abandoned shrimp farm 

80 

infrastructures that could very well be put to use 

for the development of other species, such as sea 

cucumbers. 

This paper summarises efforts made to cultivate 

I. fuscus, including methods of larval development 

and juvenile growth in land-based nursery systems 

on the coasts of Ecuador and Mexico. Major findings 

from Ecuador have been outlined previously 

(Hamel et al. 2003; Mercier et al. 2004, 2007; 

Becker et al. 2009), whereas data from Mexico are 

presented here for the first time. 

Results show that aquaculture of this species is 

feasible and that it could potentially be developed 

as an alternative to fisheries. In addition, it could be 

used to maintain sustainable harvests and eventually 

contribute to the restoration of natural populations. 

Further research to complement the work presented 

here is being conducted on the feeding, growth and 

reproductive biology of this highly prized sea cucumber, 

which is a dominant feature of the Mexican and 

Ecuadorian marine ecosystems. In time, hatchery 

production and restocking of I. fuscus might provide 

part of the solution to the current sea cucumber 

fishery crisis. 

Methods and results 

Spawning and fertilisation 

Adult sea cucumbers were routinely collected 

from nearby coastal areas in Ecuador or Mexico to 

serve as broodstock. The adults were adapted to captive 

conditions in large tanks or raceways for a few 

days or weeks prior to spawning. Various methods of 

spawning induction were initially tested. However, 

close monitoring and spawning experiments later

evealed that the species follows a predictable lunar 

spawning periodicity. Patterns of gamete release were 

investigated on the coast of Ecuador using several 

hundred newly collected individuals monitored nearly 

every month for 4 years. Between 1% and 35% of 

individuals consistently spawned 1–4 days after the 

new moon (Figure 2) (Mercier et al. 2007). Most 

81 

spawnings occurred on the same evening, although 

some gamete release was often recorded over two to 

four consecutive evenings. On a spawning night, males 

typically initiated gamete release around sunset, and 

females spawned just after the peak male broadcast. 

The percentage of spawning individuals was higher, 

and a greater overlap between male and female peak 

Figure 2. Example of the typical spawning periodicity recorded in captive 

Isostichopus fuscus in Ecuador (from Mercier et al. 2007)

spawning activity was noticed, during clear conditions 

compared with overcast conditions (Mercier et 

al. 2007). Preliminary data from Mexico confirmed 

the same lunar pattern, although individuals mostly 

started to spawn 2–3 days before the new moon, and 

continued to do so for 2–4 consecutive days. 

In Ecuador, it has thus been possible to obtain 

male and female gametes on a monthly basis; only a 

limited number of spawning trials have been unsuccessful, 

mostly due to poor environmental conditions 

(e.g. heavy rain). In Mexico, spawning events were 

recorded solely between June and December of each 

year, with maximum success in late summer and 

autumn/fall (August to December). 

The broodstock in Ecuador typically consisted of 

300–400 adults maintained in large 30-t tanks. Males 

and females were isolated in buckets as soon as they 

showed signs of imminent spawning (typical posture 

with anterior end rising and moving right to left and 

up and down). Clear morphological distinctions 

between male and female gonopores at that stage 

allowed trained personnel to sort them before the 

actual gamete release. Each female was placed separately 

in a 300-L spawning tank and maintained there 

until it had released its oocytes. Once the female had 

been removed from the tank, dry sperm obtained 

surgically from three males (sperm extracted from 

the gonad without adding any sea water until use may 

be kept at 4 °C for up to 48 hours) was diluted in sea 

water to allow cell count and prepare the solution 

required to achieve the desired final concentration of 

spermatozoa in the tanks. The best fertilisation rates 

and lowest occurrence of polyspermy were obtained 

with a concentration of 500–1,000 spermatozoa/mL. 

Spawning of both males and females occasionally 

occurred in the broodstock tanks; already fertilised 

gametes were then transferred to culture vessels. 

Similar techniques were used in Mexico. 

Larval development 

After fertilisation, the eggs were rinsed to remove 

excess sperm. A few hours later, the developing 

larvae were transferred to the hatchery tanks, 

where their development was closely monitored 

(Hamel et al. 2003; Mercier et al. 2004). The routine 

protocol included daily cleaning of the tanks during 

the first days, followed by installation of a flowthrough 

system. In Mexico, the flow-through system 

was used from the very beginning of the culture. The 

larvae were fed every day using a mix of live microalgae 

(dominated by Rhodomonas and Dunaliella 

82 

in Ecuador, and Chaetoceros and Dunaliella in 

Mexico) at a frequency and concentration dictated 

by the daily observation of digestive tract contents. 

With improvement of the rearing techniques over the 

past few years, including the use of running sea water 

and temperature control (see below), a 30–50% survival 

rate has regularly been achieved, although the 

average survivorship remains at 8–30% of juveniles 

developed from each larval run (Hamel et al. 2003; 

Mercier et al. 2004). 

Isostichopus fuscus possesses planktotrophic larvae 

that need to feed during their pelagic phase and will 

undergo a series of transformations to reach the 

juvenile stage (Figures 3–5; Table 1). In most trials, 

the development, settlement and growth of the juveniles 

were asynchronous, and different stages/sizes 

occurred simultaneously in the cultures. Extreme 

examples were observed in a few tanks where residual 

auricularia larvae neighboured 4-mm-long juveniles. 

Table 1 provides developmental kinetics for both 

countries based on the bulk of the cultures, discarding 

extreme asynchronies. Figure 6a shows the different 

sizes of juveniles that may occur in a typical cohort. 

Ovulation occurs in the gonadal tubule as the 

oocytes are released (Figure 3a). Thus, fully mature 

oocytes (~120 µm in diameter) are expelled directly 

in the water column at the metaphase-I of meiosis, 

after the germinal vesicle breakdown. Embryonic 

development is initiated with the elevation of the 

fertilisation envelope, roughly 4 minutes after fertilisation. 

The expulsion of the first polar body occurs 

~3 minutes later (Figure 3b). The second polar body 

follows rapidly within ~2 minutes. The first cleavage 

is equal, radial and holoblastic, and divides the cell 

into two equal hemispheric blastomeres (Figure 3c). 

The second cleavage again occurs along the animal– 

vegetal axis, yielding more spherical blastomeres. 

Embryos hatch from the fertilisation envelope as 

early gastrulae ~10 hours after fertilisation (Figure 

3d). These early gastrulae are ciliated and swim; 

they elongate into full-size gastrulae after ~14 hours 

(Figure 3e). Auricularia larvae, which constitute the 

first feeding stage, begin to appear ~24 hours after 

fertilisation. Growing auriculariae can be observed 

during the next 2 weeks of culture (Figure 3f; Table 

1). At this stage they begin to accumulate hyaline 

spheres. The oesophagus, sphincter, intestine, cloaca 

anus are clearly visible. After 16–18 days the auricularia 

reaches its maximum size of 1.1–1.3 mm; it has 

left and right somatocoels, as well as an axohydrocoel 

(Figure 3g) (Hamel et al. 2003; Mercier et al. 2004).

Figure 3. Early development of the sea cucumber Isostichopus fuscus; the bars represent 200 µm. 

A: Oocytes collected surgically from a mature gonad; the germinal vesicle (GV) is 

clearly visible. The insert shows a close-up of an ovulating oocyte with the follicular 

cells (FC) still attached to it. B: Fully mature, newly fertilised eggs with clear germinal 

vesicle breakdown. The insert shows the expulsion of the two polar bodies (PB). C: Twocell 

stage. D: Newly hatched gastrula. E: Elongated gastrula with visible blastopores 

(BP). F: Early auricularia on which the ciliary bands (CB), hyaline spheres (HS), buccal 

cavity (BC), oesophagus (E), intestine (I), cloaca (C) and anus (A) are identifiable; 

food items (F) are present in the buccal cavity. G: Ventral view of a fully developed 

auricularia showing the left somatocoel (LS), axohydrocoel (A), hyaline spheres (HS), 

ciliary bands (CB), buccal cavity (BC), oesophagus (E), sphincter (S), intestine (I) 

and right somatocoel (RS). H: Dorsal view of a metamorphosing auricularia. With a 

noticeable decrease in size, the buccal cavity disappears and the hyaline spheres (HS) 

are pulled closer together. The mouth (M), intestine (I), oesophagus (E), left somatocoel 

(LS) and axohydrocoel (A) are clearly visible. 

In the following hours, many auriculariae initiate 

the transformation that will lead to the doliolaria 

stage (Figure 3h). During this process, the larvae 

shrink to nearly 50% of their initial size, the buccal 

ciliated cavity disappears and the hyaline spheres 

are pressed closer together (Figure 4a). The doliolaria 

stage is reached ~19–24 days after fertilisation 

(Figure 4b; Table 1) as the larvae stop feeding and 

83 

the cilia are aligned in five distinct crowns along 

their cylindrical body. At this time, the movement 

of the primary tentacles can be observed through the 

translucent body wall. The somatocoel is also visible. 

A few days later, the doliolaria transforms into 

an early pentactula possessing five buccal tentacles 

(Figure 4c). At this stage, the larvae remain close to 

the substrate, successively going through swimming

Figure 4. Late development of the sea cucumber Isostichopus fuscus; the bars represent 

200 µm. A: Late metamorphosing auricularia, showing the hyaline spheres 

(HS), oesophagus (E), intestine (I), somatocoel (S) and axohydrocoel (A). 

B: Fully developed doliolaria with hyaline spheres (HS), primary tentacles 

(PT), ciliary bands (CB) and somatocoel (S). C: Early pentactula with five 

tentacles (T) and the still-visible ciliary bands (CB). D: Dorsal view of newly 

settled pentactula with tentacles (T) and hyaline spheres (HS). E: Ventral view 

of newly settled pentactula showing the first ambulacral podia (AP) and the 

five buccal tentacles (T). F: Early juvenile, measuring 1.5 mm in length, with 

tentacles (T), ambulacral podia (AP) and ossicles (O). The hyaline spheres 

have disappeared. G: A 2-mm-long juvenile with five tentacles (T) and three 

pairs of ambulacral podia (AP). The intestine (I) and ossicles (O) are visible. 

H: A 3-mm-long juvenile showing the tentacles (T), papillae (PA), intestine 

(I), anus (A) and ring canal and aquapharyngeal bulb (RC + APB) 

and settling phases. Definitive settlement, with the 

complete loss of cilia, completion of metamorphosis 

and emergence of the two first ambulacral podia, 

occurs about 22–27 days post-fertilisation in Ecuador 

and 17–20 days post-fertilisation in Mexico (Table 1; 

84 

Figure 4d, e). Further details on the development are 

available (Hamel et al. 2003; Mercier et al. 2004). 

Hatcheries in Ecuador use corrugated sheets of 

Plexiglas covered with a rich biofilm to provide 

settlement substrates and food to settled larvae and

early juveniles. In Mexico, conditioned, multilayered 

sheets of locally made fabric mesh are used as settlement 

substrata and during the early growth phase 

of juveniles. 

Juvenile growth 

Figure 5. Juvenile sea cucumber Isostichopus fuscus measuring 15 mm in length 

and showing the tentacles (T), early body wall pigments (P), intestine (I), 

ambulacral podia (AP), anus (A) and papillae (PA) 

Although the first settled juveniles can be observed 

as early as day 17–22, a majority of juveniles measuring 

1.0–1.5 mm in length are generally found in the 

tanks after 21–28 days of culture (Figure 4f; Table 1). 

They reach ~2–3 mm only a few days later (Figure 

4g, h), and 5 mm after ~40–48 days. At this stage, 

the juveniles start to accumulate some reddish-brown 

pigments. In 8-mm-long juveniles, the tips of the tentacles 

become ramified. After 50–65 days of culture, 

the juveniles are 15–18 mm long and 4 mm wide 

(Figure 5). They possess several papillae and an elongated 

intestine that already exhibits strong peristaltic 

movements. The body wall becomes more opaque 

as the ossicle density and the tegument thickness 

increase. When the juveniles reach ~20 mm in length, 

the whitish colouration that characterises the early 

stages of life is gradually replaced by a brownish 

tinge typical of adults (Figure 6a). After 72–85 days 

of culture, the juveniles are ~35 mm long and 10 mm 

wide (Hamel et al. 2003; Mercier et al. 2004). 

The typical growth of I. fuscus larvae and juveniles 

in Ecuador is shown in Figure 7. The average growth 

85 

of larvae and juveniles follows the second-order 

polynomial calculation (equation (1)): 

f(x) = 1658 – 321(x) + 11(x2) (1) 

where f(x) is the size in µm and x is the time in days 

(r2 = 0.99) 

The latest cultures in Ecuador have yielded significantly 

faster growth rates, with juveniles measuring 

11 mm after 28 days, 31 mm after 56 days and 

56 mm after 77 days. Growth rates are slightly slower 

in Mexico (Table 1). 

Grow-out experiments 

In Ecuador the juveniles are usually transferred 

to larger 18-m2 pre-conditioned flow-through tanks, 

with or without conditioned plates (the same as 

those used for larval settlement), when they reach 

0.5–1.0 mm in length. Mexico makes similar use of 

settlement plates for juvenile growth in flow-through 

tanks. After about 72 days, some of the juveniles have 

reached sizes up to 34 mm (Figure 7; Table 1). The 

maximum size of I. fuscus grown in aquaculture 

facilities is ~240 mm in length or ~490 g (Figure 6b). 

Juvenile I. fuscus were also successfully reared in 

shrimp ponds in Ecuador. A preliminary experiment 

was conducted early in the study to determine if small 

sea cucumbers (~100–150 g) collected from the wild 

would grow in ponds in different locations. Enclosures

Table 1. Development of Isostichopus fuscus, from fertilisation to 35-mm-long juvenile 

STAGE TIME 

Ecuador 

of 1 m 2 were used to facilitate recapture. These sea 

cucumbers grew an average of 17 g/week and exhibited 

a 98% survival rate, suggesting that shrimp ponds 

along the coast can provide a good environment to 

grow I. fuscus juveniles to adult size in a reasonable 

time frame. However, juveniles grown in tanks and 

shrimp ponds may both develop skin diseases that can 

cause massive mortality, especially during months with 

warmer temperatures and heavy rains (see below). 

In Mexico in 2009, an experimental shrimp pond 

was used for the grow-out of hatchery-reared juveniles 

(starting with 2-month-old seeds of 3–5 mm 

and 4–7 mg). During the monitoring phase they grew 

86 

TIME 

Mexico 

Fertilisation 0 0 

Elevation of the fertilisation envelope 4 minutes 5 minutes 

Expulsion of the first polar body 7 minutes 10–15 minutes 

Expulsion of the second polar body 9 minutes 16–20 minutes 

2-cell 52 minutes 21 minutes 

4-cell 70 minutes 30–40 minutes 



32-cell 140 minutes 80–90 minutes 

Blastula 3 hours 2.5–3.0 hours 

Early gastrula 6 hours 6 hours 

Hatching 10 hours 9 hours 

Late gastrula (elongation) 14 hours 11 hours 

Early auricularia 1–2 days 20–25 hours 

Auricularia 3–15 days 3–10 days 

Late auricularia (early metamorphosis) 16–18 days 11–17 days 

Doliolaria 19–24 days 13–18 days 

Early pentactula 21–26 days 14–19 days 

Settlement (metamorphosis completed) 22–27 days 17–20 days 

Juvenile, 1 mm 28 days* 21 days 

Juvenile, 2 mm 30 days 30 days 










Juvenile, 35 mm 72 days 85–90 days 

* For the juvenile stages, the time indicated corresponds to the first noteworthy observations of a particular 

size in the tanks. 

from an average of 1.07 to 42.07 g in 3 months, but 

survival was low due to outbreaks of skin disease. 

Using mesh cages at sea (1.8 × 1.8 × 1.8 m) stocked 

with 3,000 seeds resulted in a more conservative 

growth rate (from 2.66 to 26.92 g in 3 months) 

but greater survival (40–90%). The presence of 

sponges and other fouling organisms on the mesh 

(500–1,000 µm), and clogging from accumulated 

sediments, might have prevented the entry of fresh 

deposits serving as food to the juveniles. The presence 

of crabs in the cages was also noted, which 

might have caused stress (slowing growth) and possibly 

mortalities.

Figure 6. A: Juveniles of different sizes, ranging 3–25 mm in length, obtained in the same cohort. 

B: Maximum size of I. fuscus obtained through aquaculture (~24 cm long) 

Size (mm) 

34 

32 

30 

28 

26 

24 

22 

20 

18 

16 

14 

12 

10 

8 

6 

4 

2 

0 

0 4 8 

Figure 7. Average growth of larvae (black bars) and juveniles (grey bars) of the sea cucumber 

Isostichopus fuscus in Ecuador 

Diseases and other problems 

f=1658–321x+11x 2 

r 2=0.99 

Parasites of the digestive tract in larvae 

The most common problem observed during the 

culture of I. fuscus was the development of a disease 

in the digestive system of early larvae (Figure 8) 

(Becker et al. 2009). Following the appearance of 

opaque cells around the digestive tract, the second 

visible symptom was contraction of the intestine 

and stomach. In the worst cases, the digestive tract 

12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 

Time (days) 

87 

completely shrivelled up and disappeared. Once it 

became visible, the condition was usually fatal to the 

larvae. 

Upon close examination of the affected larvae 

under the microscope, the disease was determined 

to be caused by protozoan parasites (Figure 8a, b). 

During the first stage of the disease, the parasites 

can be seen entering through the body wall and the 

digestive tract, probably inducing the observed contraction. 

Later in the development of the disease, the

A B 

Figure 8. Micrographs of diseased Isostichopus fuscus. A: Auricularia larva (length 1.2 mm) with digestive tract 

invaded by parasites (arrows). B: Close-up view of the intestine with parasites (parasite diameter 12 µm) 

parasites become larger and are present everywhere 

around the intestine, both inside and outside. The 

parasites that penetrate the intestine appear to feed 

on the intestinal contents or tissues, slowly making 

it shrink, sometimes rupturing the intestinal wall 

and typically causing the death of the larva within 

1–3 days (Becker et al. 2009). 

The parasites have never been observed in the larvae 

before hatching. However, the condition develops 

rapidly shortly thereafter, suggesting that the causal 

agents are present in the surrounding environment, and 

that they enter the larvae at the first opportunity. They 

seem to remain inactive until the larvae start to feed. 

Afterwards, they can be seen to develop in different 

areas of the mouth and, most commonly, the digestive 

tract (stomach and intestine). A form with thin appendixes 

can be found attached all over the larvae, but the 

amoeboid form is mostly observed around the digestive 

organs; it has the ability to move in and out of what 

appears to be a trophosoite form (Becker et al. 2009). 

We have tried different methods of collecting the 

gametes to establish whether the parasites were coming 

from the sea water itself or from the spawning 

adults. It has proven impossible to develop a culture 

without the presence of the parasites at one stage or 

another, even when using artificial sea water from 

the onset. It would seem that the parasites are either 

present around the gametes and/or develop spontaneously 

in the culture (possibly from aerosols). 

Close monitoring of the early larval stages allows 

detection of the first occurrence of the parasites, and 

enables control of the disease through adjustments 

of environmental parameters. If the disease is not 

88 

contained in its earliest phase, the whole culture 

usually crashes. This problem is especially prevalent 

during the hottest and rainiest months of the cycle 

in both countries. Decreasing the temperature to 

~24–26 °C and increasing aeration in the cultures 

mitigates proliferation of this parasite; however, even 

lower temperatures may slow or interrupt the development 

of the larvae. 

Disease of the body wall (skin) in juveniles and 

larger individuals 

In Ecuador and Mexico, grow-out trials in shrimp 

ponds or large tanks have so far yielded mixed results, 

with significant mortality due to a disease affecting 

the body wall (Figure 9). This condition may cause 

degeneration, evisceration and eventually death. Some 

promising treatments were devised in Mexico with 

daily usage of antibiotics for several weeks, but cured 

animals could develop the disease again later on. The 

best way to prevent and cure this condition in Mexico 

is currently to grow I. fuscus directly in the ocean or 

transfer any affected individual to the field as soon as 

the skin disease is detected. 

Problems related to quality of food and water 

Due to variable and often poor environmental 

conditions along the coast where the water was being 

pumped, a very complete filtration system, including 

UV treatment, had to be installed to provide the best 

possible water quality throughout the trials. The conventional 

treatment used for prawn culture was not 

dependable enough to grow sea cucumber larvae with 

optimum success, especially I. fuscus, which requires

Figure 9. A: Juveniles and B: adult individuals of Isostichopus fuscus affected by body wall (skin) 

disease; individuals are ~2–3 cm long in A and ~20 cm in B. 

high-quality oceanic water. Strict sanitary measures 

were adopted in the handling of gametes and larvae 

to maximise survival rates and minimise incidence 

of infections and diseases. Bacterial counts were 

routinely made from water samples to monitor the 

efficiency of the sanitary and filtration procedures. 

Bacterial contamination of algal cultures was 

another common problem that had to be overcome. 

Growing larvae need large quantities of healthy 

live algae to develop steadily, especially during the 

auricularia stage. Inability to provide a healthy mix 

of algae can significantly delay growth and metamorphosis 

for extended periods. Thus, it has proven 

crucial to develop a system of algae production that 

is reliable and efficient. 

As the size of the cultures grew from a few tens 

of thousands to over 2–3 million larvae per month, 

rearing conditions had to be maintained and eventually 

improved to avoid mass mortalities. 

Outlook 

After 10 years of research and development: 

• A good portion of the effort has been placed on 

adapting shrimp farm equipment and larval rearing 

conditions to fit the needs of I. fuscus. 

• The species has been found to follow a predictable 

lunar spawning cycle, which facilitates the collection 

of mature gametes (oocytes and spermatozoa). 

• A larval rearing protocol has been developed using 

flow-through systems, an optimal micro-algae diet, 

water quality management and disease control. 

89 

• In successful trials, survival rates from fertilised 

egg to settlement varied from 2–13% in Mexico 

to ≥30% in Ecuador. 

• Based on the best growth rates, juveniles can reach 

8 cm (~25–27 g) in 110 days in shrimp ponds 

(Ecuador) and 90 days in cages (Mexico), with 

survival rates of up to 90%. 

• While grow-out of sea cucumbers in tanks and 

shrimp ponds appears to be promising under optimal 

conditions, cage culture (sea farming) might 

be a more reliable and simple option because it is 

free of disease. 

Future goals 

Future research aims to: 

• improve the diets and conditioning of adults to 

spawn when maintained in tanks to avoid having 

to continuously collect broodstock from the wild 

• finetune hatchery and larval rearing protocols to 

maximise (scale-up) commercial mass-production 

• optimise the control of larval and juvenile parasitic 

infestations and infections 

• experiment with grow-out techniques to determine 

the best diet, substrates and location to grow the 

sea cucumbers to commercial size 

• determine the commercial and ecological prospects 

for hatchery-produced I. fuscus (e.g. marketing, 

restocking) 

• explore the possibility of culture away from shrimp 

habitat / installations.


The authors would like to acknowledge the hard work 

and technical assistance of Jorge Jaramillo, Jose 

Pico, Pedro Gonsaby and Maricela Garcia during the 

course of the laboratory work in Ecuador, as well as 

Ramon Cota, Cesar E. Magallanes Raygoza, Cristian 

Eden Sagueiro Beltran, Karla Marina Garcia Quiroz, 

Juan Jose Beltran Sanchez and Javier Cervantes 

Zambrano in Mexico. 

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J.-F. 2009. Protozoan disease in larval culture of the 

edible sea cucumber Isostichopus fuscus. Pp. 571–573 

in ‘Echinoderms’, ed. by L.G. Harris, S.A. Bottger, C.W. 

Walker and M.P. Lesser. CRC Press, London. 

Castro L. 1993. The fisheries of the sea cucumbers 

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in Baja California, Mexico. Proceedings of the 8th 

International Echinoderm Conference, Dijon, France, 

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impatiens and Parastichopus parvimensis fisheries. SPC 


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Singh-Cabanillas J. and Michel-Guerrero E. 1995. 

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sea cucumber Isostichopus fuscus (Echinodermata: 

Holothuroidea) in Santa Rosalia, Southern Baja 

California, from September 1992 to September 1993. 

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for culturing the sea cucumber Isostichopus fuscus 

in the sea of Cortez, Mexico. Institute of Aquaculture: 

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in Mexico. SPC Beche-de-mer Information Bulletin 11, 

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Dominguez F. and Cintra-Buenrostro C.E. 1999. 

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(Echinodermata: Holothuroidea) in the southern Gulf 

of California, Mexico. Marine Biology 135, 521–532. 

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in the Galapagos Islands: Ecuador’s sea cucumber 

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risk or an opportunity for conservation? SPC Beche-demer 


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study of gamete release in a broadcast-spawning holothurian: 

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and Isostichopus fuscus, from the Gulf of California. 

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biology and population structure of the sea cucumber 

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United Nations: Rome.

Sandfish sea ranching and farming 

Brushing sea-pen netting to remove biofouling, Ambolimoke, 

south-western Madagascar (Photo: Georgina Robinson) 

91

Principles and science of stocking 

marine areas with sea cucumbers 

Steven W. Purcell 1* 

Abstract 

Clearly stating the goals of stocking builds an essential platform for success. The scales, methodologies, management 

and time frames of the interventions can then be matched to the original goals. Stock enhancement, 

restocking and sea ranching will involve different stocking strategies. The genetic risks to wild stocks must 

be minimised by preventing translocation of juvenile sea cucumbers to different locations than those where 

broodstock were collected, unless studies show broad genetic homogeneity of the stock. Cultured juveniles 

are easily marked by immersion in a fluorochrome solution (e.g. tetracycline or calcein), which provides a 

long-term, unequivocal means of distinguishing hatchery-produced animals from wild conspecifics. Use of 

open sea pens is an experimental tool that provides better estimates of early stocking success. Juvenile density 

can be assessed by searching through sand and mud in quadrats by hand, whereas sub-adults and adults can 

be surveyed visually in transects with a stratified arrangement. Proponents of sea cucumber stocking in the 

wild should be conservative and realistic about the expected returns; 1 in 5–10 (10–20%) of released juvenile 

sea cucumbers surviving to market size is a benchmark. Clear goals, use of existing technology, and realistic 

expectations in sea ranching and restocking of sea cucumbers will provide the foundation for success. 

Background 

Stocking of marine invertebrates 

While fish have been stocked into the sea since 

long ago, stocking of cultured marine invertebrates is 

mostly fairly recent (Bell et al. 2005). Notable invertebrates 

used in marine stocking include scallops and 

other bivalves, sea urchins, abalone, lobsters, Queen 

conch, giant clams and trochus. In the past, most 

stocking programs were unsuccessful in biological and 

economical terms (Leber et al. 2005; Bell et al. 2006). 

Poor survival of the released juveniles can be attributed, 

to a large extent, to inept knowledge about how, 

when and where to release the animals so that they 

may survive in high numbers (Liao et al. 2003; Purcell 

2004; Lorenzen et al. 2010). Consequently, stocking 

programs started releasing cultured juveniles before 

1 National Marine Science Centre, Southern Cross 

University, Coffs Harbour New South Wales, Australia 


92 

the technology was developed to know how they 

should be released. This is unfortunate because stocking 

was thus criticised as a questionable management 

intervention even before the technology for many species 

was given the chance to be developed and proven 

(Hilborn 1998; Molony et al. 2003). 

In recent times, criticism about stocking success has 

fostered a new era for programs to both develop release 

strategies through research before large-scale releases 

and conduct stocking in a responsible way (Blankenship 

and Leber 1995; Lorenzen et al. 2010). Key elements 

to responsible stocking are: (1) a requirement to demonstrate 

stocking success using marking of juveniles, 

(2) precautions to avoid disease transfer from hatchery 

stocks to the wild and (3) making efforts in the hatchery 

to produce juvenile cohorts with a wide genetic pool 

that closely matches the genetic make-up of the wild 

stocks among which the juveniles are released. As a 

consequence, greater scientific rigour in stocking 

programs is now giving back confidence in restocking, 

sea ranching and stock enhancement as potentially costeffective 

management tools (Bell et al. 2006, 2008).

Stocking of sea cucumbers 

Stocking marine areas with sea cucumbers is a 

relatively nascent intervention (Battaglene and Bell 

2004; Bell et al. 2005). Small-scale trials of stocking 

cultured sandfish (Holothuria scabra) in the sea 

appear to have commenced in the early 1990s in India 

(James 2004) and the late 1990s in Solomon Islands 

(Dance et al. 2003). 

The Australian Centre for International 

Agricultural Research (ACIAR) embarked on 

a long-term program to assess the best tropical 

candidate species for restocking, develop hatchery 

technology for producing juveniles en masse, 

develop optimal release strategies, and apply the 

technology on a larger scale to test whether tropical 

sea cucumbers could be restocked or grown economically 

for village-based sea ranching. The first 

component, in Solomon Islands, determined that 

sandfish (Holothuria scabra) was the best species 

for tropical stocking, developed enough hatchery 

technology to produce them reliably for smallscale 

releases (Battaglene 1999; Battaglene et al. 

1999) and studied the juvenile ecology (Mercier 

et al. 1999, 2000). The second component, in New 

Caledonia, adapted the larval culture and grow-out 

methods (Agudo 2006), developed methods to 

transport the juveniles (Purcell et al. 2006a) and 

technology for mark–recapture research (Purcell et 

al. 2006b; Purcell and Blockmans 2009), assessed 

release density and size-at-release in long-term 

release experiments (Purcell and Simutoga 2008), 

and evaluated restocking design (Purcell and Kirby 

2006). The third component, being conducted 

in the Philippines and the Northern Territory, 

Australia, aims to determine whether the benefits 

of stocking sandfish for village-based sea ranching 

outweigh the costs of stocking (Juinio-Meñez 2012; 

Fleming 2012). 

Purposes of stocking 

The goals of stocking interventions will govern 

the management regulations needed and the spatial 

context of the releases. It is easy for agencies to 

develop a keen interest in culturing and stocking 

sea cucumbers in the wild without a clear description 

of the ultimate goals of the intervention. Such 

ambiguity can lead to false expectations of the 

likely outcomes, ownership or access issues, and the 

scale of releases and companion measures needed 

93 

to achieve success. The path to failure in stocking 

programs is therefore often paved with uncertainty 

about the ultimate goals. 

Stocking is a general term used here to mean 

the release of sea cucumbers into the sea with the 

expectation that they will then grow to larger sizes. 

Bell et al. (2005, 2008) and Bartley and Bell (2008) 

defined different types of stocking interventions, 

which are paraphrased, respectively, below. 

• Sea ranching: the release of cultured juveniles 

into open (non-bounded) habitats in the sea for 

harvesting once they reach market size. This is a 

‘put, grow, and take’ strategy relying on sole access 

rights (e.g. via lease of an area) to the proponents, 

without a main objective of increasing the yield of 

the overall fishery. 

• Restocking: the release of cultured juveniles into 

natural habitats to build nucleus breeding populations 

that will subsequently breed and replenish 

recruitment to repopulate the broader fishery. 

This modality is predicated on protection of the 

released animals from fishing, ideally for their 

life span. 

• Stock enhancement: the release of cultured juveniles 

into the broader fishery to grow and later 

improve yields to fishers granted access to fishing 

grounds. This modality does not have a main 

objective of rebuilding egg supply for generational 

stock rebuilding, and does not rely on sole access 

to stocked areas within the fishery. 

Sea farming is another type of stocking, which is 

done into impoundments and artificial habitats (e.g. 

earthen ponds) supplied with sea water, but it is not 

examined in this paper. 

The pathways to impact in restocking interventions 

are rather long compared with sea ranching 

(Figure 1). The main reason is because restocking 

relies not only on the survival of released animals to 

maturity, but also that they breed in the wild and that 

their offspring repopulate fishing grounds and survive 

to maturity (also see Molony et al. (2003)). The 

success of this latter, vital step of restocking is most 

difficult to demonstrate scientifically (Battaglene and 

Bell 2004; Purcell 2004). In contrast, sea ranching 

requires only that the stocked animals survive in 

high numbers to a market size. 

Proponents should be explicit about whether the 

aim is to release animals that will be harvested by 

a particular group of people, or to rebuild depleted 

wild populations, or to enhance fishery yields for 

all fishers.

Communication and participation with stakeholders 

Preserving the integrity of 

wild stocks 

Risks of translocation 

Steps in restocking 

Correct the fishery 

management problem 

Nominate existing reserves or 

create no-take zones for restocking 

Collect broodstock and 

breed them in a hatchery 

Release juveniles in ways to 

maximise survival to maturity 

Protect the released animals in 

the reserve for their lifespan 

Larval supply from the 

restocked breeding population 

rejuvenates recruitment in 

neighbouring fishing grounds 

The offspring from restocked 

animals survive in fishing 

grounds and grow to adulthood 

The offspring from 

restocked animals 

can be fished 

Breeding populations in 

local fishery are rebuilt 

Figure 1. Important steps in restocking and sea ranching. Restocking relies on survival of 

the restocked animals to maturity and survival of their offspring to maturity. Also 

important through the steps of both interventions is frequent communication and 

participation of stakeholders. 

The ability to produce juveniles in the hatchery 

often spurs the desire to release them at various sites 

for various purposes. However, the genetic identity 

of local stocks, even those suppressed to low levels 

by fishing, should be maintained (Hindar et al. 1991; 

Utter and Epifanio 2002; Lorenzen et al. 2010). Some 

sea cucumbers such as black teatfish (Holothuria 

whitmaei) have high gene flow among populations, 

suggesting that larvae travel long distances and maintain 

genetic mixing among populations (Uthicke and 

Benzie 2000, 2003). In contrast, species such as the 

sandfish (Holothuria scabra) have restricted gene flow, 

94 

Steps in sea ranching 

Gain access rights over an area 

of optimal habitat for ranching 

Collect broodstock and 

breed them in a hatchery 

Release juveniles in ways to 

maximise survival to maturity 

Protect the released animals in 

the ranching area until they 

reach an optimum market size 

Improved recruitment to 

neighbouring fishing 

grounds is a secondary 

effect 

Harvest all animals 

Communication and participation with stakeholders 

causing certain populations to be relatively isolated 

from others, even within a country, and leading to 

unique genetic differences between populations at 

scales of less than 100 km (Uthicke and Benzie 2001; 

Uthicke and Purcell 2004). Native stocks may have 

particular genes that predispose them to cope much 

better with local environmental stresses that may occur 

periodically (Templeton 1986; Waples 1995). 

Stock translocation may lead to reduced fitness of 

resident populations through outbreeding depression 

and introgression (Utter 1998; Uthicke and Purcell 

2004). That is, introduced stock can outcompete with 

local stock (both ecologically and reproductively) or 

can interbreed with local stocks, leading to a loss 

in the genetic differentiation between populations. 

It is possible that introgression of foreign stocks 

could reduce the fitness of the population to deal

with occasional environmental stresses (Figure 2). 

Such effects are not just theoretical; studies show that 

translocation of fish can negatively affect local populations, 

and the introduction of foreign genes can lead 

to long-lasting effects that are usually irreversible 

(Hindar et al. 1991; Waples 1995; Utter 1998). 

Are there some instances when translocation of 

foreign stock could be responsible? In some cases, 

populations have been depleted to extinction such 

that teams of divers could not find even a small 

number to serve as hatchery broodstock for restocking, 

and years have passed without successful natural 

recruitment (Bell et al. 2005). If proponents can produce 

rigorous data to convincingly show this to be the 

case, foreign translocation of new stock may be the 

only practical solution to restoring populations, but 

such interventions should not be swayed by private 

economic interests. Additionally, responsible restocking 

in such cases would use broodstock of the closest 

populations from which broodstock can be collected. 

Population viability relies on genetic variability 

among individuals (Waples 1995). Using a large 

number of spawning animals in each spawning event 

in the hatchery, and taking care with using different 

sperm from different males to fertilise different 

groups of eggs (to avoid sperm dominance), will help 

to produce genetically diverse juveniles for stocking 

in the wild (see Utter 1998). 

A: Native population stocked with native juveniles 

Translocation 

(foreign stock) 

Stocking 

(native stock) 

B: Native population stocked with foreign juveniles 

95 

Use of markers 

Technology for stocking 

In a ‘responsible approach’ to stocking 

(Blankenship and Leber 1995; Lorenzen et al. 2010), 

cultured animals stocked in the wild are first tagged 

or marked. Marking the juveniles allows them to be 

distinguished from wild conspecifics, and provides a 

means to evaluate the effectiveness of the intervention 

(Figure 3). The ability of sea cucumbers to shed 

tags inserted in their body wall or coelomic cavity 

prevents the retention of most tags used in fisheries 

biology, including streamer tags, T-bar tags, codedwire 

tags, visible implant elastomer tags and passive 

induced transponders (Conand 1990; Kirshenbaum 

et al. 2006; Purcell et al. 2006b, 2008). 

Genetic ‘fingerprinting’ of individual sea cucumbers 

provides an accurate marking method (Uthicke 

and Benzie 2002; Uthicke et al. 2004), but the 

method is relatively costly. This method has not been 

applied yet to cultured sea cucumbers. Alternatively, 

sea cucumbers can be marked with fluorochromes, 

which fluorescently marks the ossicles (spicules) 

in the outer body wall of the animals. This procedure 

can be as cheap as 2 cents (US) to mark a 5-g 

juvenile (Purcell et al. 2006b). Fluorochromes such 

as tetracycline and calcein have been shown to be 

Interbreeding 

Stress event 

Stress event 

Figure 2. Illustration of one risk of translocation of foreign stock. A: Hatchery-produced juveniles from local 

(native) broodstock are stocked into the local population, the genetic identity of the stock is preserved, 

and the population is able to cope well with a stress event. B: Hatchery-produced juveniles from foreign 

broodstock (from a genetically different population) are translocated into the local population, the 

genetic identity of the stock is greatly reduced through introgression, and the interbred population no 

longer has the previous tolerance to cope with certain stress events.

A: Sea ranching or restocking with unmarked juveniles 

Unmarked juveniles 

stocked 

B: Sea ranching or restocking with marked juveniles 

Figure 3. Diagrammatic illustration of pitfalls in releasing unmarked sea cucumbers in the wild. A: Unmarked 

cultured juveniles are released into an area that receives some natural recruitment of wild juveniles—it 

is impossible to validate how many, or what percentage, of the cultured animals survived over time. 

B: Marked cultured juveniles are released into an area that receives some natural recruitment of wild 

juveniles—the markers allow the cultured animals to be later distinguished from wild conspecifics mixed 

in the population to validate how many, or what percentage, survived over time. 

suitable for up to about 2 years (Purcell and Simutoga 

2008) (Figure 4), and 2-month trials with calcein blue 

and xylenol orange have shown long-term promise 

(Purcell and Blockmans 2009). 

Cultured juveniles can be immersed in a marker 

solution in mass numbers in the hatchery within 

completely shaded flat-bottom tanks (Figure 5). The 

animals must be in a growth phase for the ossicles in 

Ossicles under 

normal light 

Marked juveniles 

stocked 

96 

Wild recruits 

1–2 years 

Wild recruits 

1–2 years 

Survival rate of released 

animals is uncertain 

their body wall to take up the fluorochromes (Purcell 

and Blockmans 2009). Fluorochromes are combined 

into the carbonate structure of ossicles during the 

process of calcification, and only that portion (e.g. 

10–50%) of their ossicles being developed will be 

marked (Purcell et al. 2006b; Purcell and Blockmans 

2009). Some juveniles may be slightly yellowish for 

a short time after immersion, but afterwards they are 

?? 

Survival rate of released 

animals can be proven 

unequivocally 

Same ossicles 

under fluorescent 

light only 

Figure 4. Ossicles (spicules) of Holothuria scabra individuals that had previously been marked sequentially 

by tetracycline then calcein (2 weeks later). Left: a field of view of ossicles under the microscope 

with normal light; right: the same field of view of the same ossicles under fluorescent light in an 

epifluorescence microscope. Note that about half of the ossicles have been marked—some that were 

fully formed were not marked during the immersion treatment.

Figure 5. Fluorochrome stock solution is added to a 

large tank with aerated sea water and a heater 

to maintain water conditions. The animals are 

left for 12–24 hours in the solution to enable 

effective marking of the ossicles within their 

outer body wall. 

indistinguishable in outer appearance from unmarked 

animals. If ossicles are unmarked, or weakly marked, 

after an immersion treatment, it may be that (1) the animals 

were not growing well before the treatment (i.e. 

they were ‘stunted’), so their ossicles were not being 

developed; (2) the conditions, such as the temperature 

of the immersion solution, were not well maintained; 

or (3) the fluorochrome chemicals were inactive—e.g. 

tetracycline can be damaged by light and heat. 

The materials needed for verification of fluorochrome 

markers are surprisingly basic, and the 

methods are cheap and simple (Figure 6). Small tissue 

samples can be taken from the ventral surface of the 

sea cucumbers in the field. Most ossicles are about 

50–100 µm long and there are thousands of ossicles 

in each cubic millimetre sample of outer body wall of 

sandfish (Purcell et al. 2006b). Once in the laboratory, 

the samples are simply soaked for 30 minutes in household 

bleach to digest the soft tissue, which leaves the 

ossicles in the sample container. The ossicles are rinsed 

with fresh water to remove the bleach, then dried and 

observed under an epifluorescence microscope. 

Use of sea pens 

In some situations, sea pens may be used for 

farming sea cucumbers to market size. For instance, 

it may be important to separate sea cucumbers from 

other animals or to keep them from moving into other 

areas where they can be fished (e.g. Robinson and 

97 

Pascal 2009, 2012). However, sea pens can be costly 

(materials and set-up), require regular maintenance 

and do not allow sufficient space for large numbers of 

animals unless the pens are very large. Sea ranching 

of large numbers of sea cucumbers would involve an 

area (e.g. a sheltered bay) of good habitat in which 

the ranching proponents have exclusive access to the 

animals, and where the animals could be released into 

that area without sea pens. So long as the habitat is 

optimal or good for the species, the sea cucumbers 

will not be likely to move far in the years before they 

are harvested (Mercier et al. 2000; Purcell and Kirby 

2006). Sea pens are, therefore, mostly advantageous 

as experimental tools to help the researcher better estimate 

survival and growth of released sea cucumbers. 

Up to a size of about 50–100 g, juvenile sandfish 

can crawl up the walls of sea pens made of plastic 

mesh. Escape then causes an underestimation in survival 

rates. We conducted short trials in a hatchery tank 

with sand to test different designs of small (0.1 m 2) 

prototype sea pens in an attempt to find a design that 

would prevent 2–10-g juveniles from escaping. Copper 

wire sewn to the upper edge of the mesh deterred 

animals from moving over it and escaping, but was 

toxic. In a weakly replicated (n = 2) test over 24 hours, 

fewer juveniles escaped (climbed over) pens with mesh 

skirting (mean = 25% escape) compared with pens 

with the upper edges folded inwards (mean = 60% 

escape) or pens with simple straight edges (mean = 

70% escape). Juveniles were observed to crawl up the 

mesh wall, but fell back into pens when they crawled 

to the edge of the net skirts. We therefore used small 

sea pens of 1 m 2 with mesh skirts for small experiments 

on release strategies (Figure 7). Later, we tested 

escape rates of similar sized juveniles from prototype 

pens in the hatchery that had a strip of antifouling 

painted on the upper edge, and found that escape rates 

over 24 hours were comparable with those using the 

mesh skirts. As mesh skirts were difficult to make, we 

used an antifouling strip on the upper 10-cm surface 

of the pen walls for large pens (e.g. 500 m 2). Note 

that the risk of escape is much higher with smaller 

pens because the animals are in close proximity to the 

pen walls; hence, escape rates from small pens are not 

indicative of those from large pens. 

Surveys 

Surveys for juvenile sandfish

A 

C 

Figure 6. Steps in collecting and processing tissue samples of sea cucumbers to distinguish 

marked animals from unmarked (wild) ones. A: A tiny sample (a few mm 2) of the 

outer body wall is taken from the ventral surface of the animal, which is returned 

to the sea. B: The tissue sample is placed into a cell of a tray and buffered alcohol 

is added to preserve it. C: The alcohol is removed, bleach is added for 30 minutes 

to digest the soft tissue, then the bleach is removed and the ossicles are rinsed five 

times with freshwater. D: Once dry, the tray is placed under an epifluorescence 

microscope to look for fluorescently marked ossicles. 

Figure 7. A small sea pen of 1 m 2 set into a seagrass 

bed. A mesh skirt on the upper edge of the 

pen mesh helps to prevent juveniles from 

escaping by climbing over the sea pen wall. 

98 

B 

D 

juvenile sandfish. The solution is to assess densities 

of juveniles within randomly placed quadrats of 

1–2 m 2 by laying the quadrat and manually searching 

through the upper 5 cm of sediment by hand. 

It is useful to estimate the survival rate in the initial 

months after release, when the animals are still juveniles. 

Within sea pens, quadrat surveys for sandfish 

should be stratified—some should be placed against 

the inner wall of the sea pen and some in the centre 

area of the pen (Figure 8). This is necessary because 

sea cucumbers will tend to gather near the edge of 

the sea pen through random movements (Jeanson et 

al. 2003), so this zone should be surveyed separately 

(Purcell and Simutoga 2008). 

Once the animals in a sea pen are large enough to 

count reliably using visual census, the sea pen may be 

removed to allow the animals to displace over a larger 

area and avoid crowding. Conversely, the sea-ranching 

program may have simply released animals into 

the open and waited 6–12 months before doing visual 

surveys. In most sea-ranching situations, the animals

Quadrats 

(1 m 2 ) 

Quadrats (2 m 2 ) 

Figure 8. Potential placement of random quadrats within experimental sea pens. The number of animals within the 

border area—50 cm inside the inner wall of the pen mesh—can be sampled with rectangular 1-m 2 quadrats 

(2 × 0.5 m). Animals within the inner area can be sampled with square 2-m 2 quadrats (1.41 × 1.41 m). 

would be released near the middle of the managed 

area at moderate density (e.g. 1/m 2). Through random 

displacement over long time intervals (see Purcell 

and Kirby 2006), some of the animals will move 

relatively large distances from the release area (e.g. 

100 m), many would move short distances from the 

release area (e.g. up to 50 m) and many would stay 

in the release area. The uneven density of released 

animals calls for a stratified survey design (Figure 9). 

Zones can be marked out—for example, using buoys 

at the corners—to delineate the release zone (central 

zone), a middle zone and the outer zone. Transects 

can then be laid randomly in each zone, increasing 

replication in zones successively further from the 

release area to account for greater variability in 

counts within the replicate transects from increasing 

patchiness and sparseness of sea cucumbers. 

Where to release? 

Nature should be a useful guide to choosing good 

sites for stocking sea cucumbers. For example, 

sandfish (Holothuria scabra) larvae appear to settle 

on seagrass blades, and juveniles are known to 

inhabit shallow seagrass beds (Mercier et al. 2000). 

Sites with a current or previous history of hosting 

the species should be a sensible start. It may be that 

some sites never really were home to the species 

99 

Pen fence wall 

Border area within 

pen (imaginary) 

Inner area within 

pen 

of sea cucumber but could serve as good stocking 

sites; however, this will generally be rare. Avoid sites 

with widely varying environmental conditions; for 

example, areas periodically subject to freshwater 

deluges. Likewise, avoid areas that may be vulnerable 

to pollutants (see Purcell and Simutoga 2008). 

In an experiment in New Caledonia, we set up 30 

replicate 1-m 2 experimental sea pens with net skirts 

15 cm into sediments within various locations in a 

bay such that each pen had a different undisturbed 

habitat composition (S.W. Purcell, unpublished data). 

A group of 25 juveniles (2–10 g) was weighed and 

released into each sea pen. After 1 week, the juveniles 

surviving in each enclosure were collected by 

hand and an air-uplift suction device, and re-weighed. 

Preliminary analyses suggest that microhabitats for 

optimal growth and survival of the juveniles would 

have the following traits to ensure their protection 

from predators and allow them to bury easily: 

• shallow—0.2 m to about 2–3 m depth 

• a low proportion of coral or coral rubble in the 

sediments 

• moderate penetrability of sediments; muddy-sand 

appeared best and should allow a hand to be forced 

easily to a few centimetres depth 

• moderately high seagrass coverage, preferably 

in the genera Cymodocea, Thalassia and 

Syringodium.

Central zone 

(release) 

Middle zone 

Outer zone 

Figure 9. Potential design for transect surveys within a coastal seagrass 

bed in which cultured sea cucumbers (small oval figures) have 

been previously released for sea ranching, and have moved out 

of the central release zone. Bars are belt transects (e.g. 2 × 50 m) 

laid randomly within three zones (red dashed lines), which are 

defined at the site by buoys or other permanent markers at the 

corners of each zone. Stratified sampling is used; that is, the 

number of transects increases from the central zone to the outer 

zone because the sea cucumbers are expected to become sparser. 

Expected returns 

Unfortunately, but quite predictably, most of the 

small juvenile sea cucumbers released in the wild 

will not survive. Predation is the biggest hurdle in 

stocking a wide variety of invertebrates, and most of 

the released juveniles die or are eaten by predators 

shortly after being released (Bell et al. 2005). Many 

different animals eat sea cucumbers, particularly 

when they are young. Known predators of tropical 

sea cucumbers include a wide variety of crabs, 

predatory gastropods, sea stars, sea birds, and fishes 

including pufferfishes (Tetraodontidae), emperor 

fishes (Lethrinidae), triggerfishes (Balistidae) and 

wrasses (Labridae) (Dance et al. 2003; Francour 

1997). Personal experience with various release 

experiments in New Caledonia suggests that invertebrate 

predators, especially crabs and sea stars, 

are especially voracious predators of juvenile sea 

Random transects 

for visual surveys 

100 

cucumbers. These observations correspond closely 

with reports of crab predation in Madagascar (Lavitra 

et al. 2009; Robinson and Pascal 2012). 

Modelling of survival rates of 5-g released juveniles 

showed that 7–20% of sandfish released in New 

Caledonia could be expected to survive to a good 

market size of 700 g 2.6 years after being released for 

sea ranching (Purcell and Simutoga 2008). Therefore, 

a conservative estimate of survival to this size would 

be about 1 in 10 (Figure 10). A survival rate of 

around 20% to this size over roughly 3 years could 

be achieved if conditions were favourable over the 

ranching period. This notion corresponds closely with 

shorter durations of some other recent studies. In Fiji, 

Hair (2011) determined survival rates of 23–41% for 

sandfish in sea pens over just 6 months, and the animals 

had not reached a market size. Similarly, in the 

Philippines, a survival rate of 39% was reported by 

Juinio-Menez et al. (2012) for sandfish in a sea ranch;

Released juveniles Sub-adults 

Adults 

however, these comprised juveniles from batches 

released at various occasions over a 19-month period, 

and many had been recently released. 

Overly optimistic predictions of economic returns 

from sea ranching will give expectations to villagers 

that will be difficult to meet, and proponents may benefit 

more from conservative expectations and praise at 

exceeding them. Estimates of economic viability of 

sea ranching can then be made by back-calculating 

revenue from the harvested animals to the maximum 

cost of producing juveniles in hatcheries to make a 

profit (see Leber et al. 2005; Purcell and Simutoga 

2008). Two additional points should be considered: 

1. As with other mariculture programs, some 

patience and investment is needed early on 

because it often takes years to reduce the costs 

of producing juveniles and to perfect release 

methods. 

2. Benefits to communities extend beyond the economic 

(Lorenzen et al. 2010); sea ranching and 

restocking can build technical capacity and foster 

awareness for better stewardship of the resource 

by communities, which should be considered a 

valuable outcome for fishery managers. 


For assistance in field and hatchery experiments 

presented in this paper, the author thanks N. Agudo, 

P. Blazer, B. Blockmans, E. Danty, E. Vigne, A. le 

Turc and C. Sanchez. The research components were 

conducted through the WorldFish Center, and received 

financial support from the Australian Centre for 

International Agricultural Research (ACIAR), the three 

provinces of New Caledonia, and the Government of 

France via the Délégation Française, Noumea. This is a 

2–3 years 

Figure 10. Stylised diagram of changes in size and numbers of sea cucumbers, due to death and predation, from 

the time of release in the wild to the time at which they reach a good marketable size 

101 

contribution of the National Marine Science Centre and 

Marine Ecology Research Centre of Southern Cross 

University. 

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103 

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Hampshire.

Pond grow-out trials for sandfish 

(Holothuria scabra) in New Caledonia 

Natacha S. Agudo 1* 

Abstract 

Sandfish (Holothuria scabra) is a high-value tropical sea cucumber widely distributed in the shallow waters 

of the Indo-Pacific. In New Caledonia, sandfish are locally called ‘gris’ and have been harvested since the 

1840s. The WorldFish Center in New Caledonia grew cultured juvenile sandfish in earthen ponds to assess 

the potential for farming the species. In this paper, we report on pond culture grow-out of sandfish from small 

juveniles to market size in a 21-month trial. Sandfish in two ex-shrimp ponds reached mean weights of 390 

and 441 g after 19 and 21 months, respectively. The overall average weight gains were estimated to be 0.60 g 

and 0.77 g per animal per day, and overall survival to be 69% and 41%, respectively. Some mortality occurred 

in ponds due to high water temperature and salinity. Beche-de-mer produced from the pond-grown sandfish 

had a darker skin colour and most was classified as grade-A, although cultured animals lost twice as much 

weight as the wild sandfish during processing. Positive features were the homogeneous sizes of pond-grown 

animals and the potential for reduced fluctuations in numbers. Recommendations for improving sandfish 

farming in ponds centre on the management of animal density and the practice of alternating earthen ponds. 

Introduction 

Sandfish, Holothuria scabra, is a tropical sea cucumber 

widely distributed in the shallow waters of the 

Indo-Pacific (Conand 1998). This species has a high 

commercial value on the international market once 

processed by boiling and drying into beche-de-mer 

(also called trepang). In New Caledonia, sandfish 

are locally called ‘gris’ and have been harvested 

since the 1840s (Conand 1990). The current fishery 

is composed mainly of Indigenous artisanal fishers 

(Purcell et al. 2002). The price for beche-de-mer 

exports depends on its quality and size, and in 2007 

was in the range US$21–47/kg in New Caledonia. 

Over the past 10 years, exports of beche-de-mer from 

New Caledonia have ranged from 40 to 80 tonnes 

annually according to the Institut de la Statistique 

et des Etudes Economiques de Nouvelle-Calédonie 

(ISEE). 

1 Current address: Aquarium des Lagons, Noumea Cédex, 

New Caledonia 


104 

Pioneering work on sandfish spawning and rearing 

was done in India in 1988 at the Central Marine 

Fisheries Research Institute (James et al. 1994). 

Rearing methods were then developed further by the 

WorldFish Center (formerly ICLARM) in Solomon 

Islands (1996–99), Vietnam (2000–04) and New 

Caledonia (2000–06). The main focus of the research 

by the WorldFish Center in New Caledonia was the 

release of juveniles into enclosures in the wild to 

determine the optimum size and density for restocking 

and stock enhancement. Additionally, some of the 

cultured juvenile sandfish produced in New Caledonia 

were on-grown in earthen ponds to assess the potential 

for farming the species. Preliminary results were 

reported by Bell et al. (2007). In this paper, we report 

more details on pond-culture grow-out of sandfish 

from small juveniles to market size (400–600 g). 

Methods 

The grow-out trials for sandfish were conducted over 

21 months between June 2005 and March 2007. Two 

0.2-ha earthen ponds (A and B) on a private shrimp

farm at Tontouta, 50 km north of Noumea, were 

used (Figure 1). All juveniles used for these trials 

were reared in the WorldFish Center’s sea cucumber 

hatchery at Saint Vincent (Boulouparis, 73 km 

north of Noumea) using the methods described by 

Pitt (2001) and Agudo (2006). Pond A was stocked 

with juveniles that had a mean weight of 0.9 g at 

a stocking density of 1.6 individuals/m 2. Pond B 

received larger juveniles (mean weight of 11.7 g) at 

a density of 0.8 individuals/m 2. The grow-out trials 

commenced during winter on 6 June 2005, when the 

average water temperature was 22 ºC. 

Both ponds had a maximum depth of 1 m and 

a muddy substratum. The ponds had previously 

been used for maintaining shrimp (Litopenaeus 

stylirostris) broodstock, but had been empty since 

2002. They were filled with sea water 2 weeks 

before transferring the sandfish juveniles. No food 

or fertiliser was added. Daily water exchange usually 

varied between 30% and 60%, but fell to less than 

10% on one occasion due to a broken water pump. 

Water temperature (ºC), salinity (ppt), dissolved 

oxygen (ppm) and secchi disk (cm) measurements 

were taken twice a day, in the morning and in the 

afternoon. 

Figure 1. Earthen pond used for growing out sandfish 

105 

To estimate the growth of sandfish, the mean 

wet weight (g) of 30 individuals from each pond 

was measured each month. Animals were collected 

at random, dried in the shade for 5 minutes, then 

weighed with a digital balance. Survival of sandfish 

in each pond was determined by counting all animals 

when the ponds were drained at the conclusion of 

the trial. 

Harvested sandfish were processed by a professional 

into beche-de-mer by gutting, boiling, soaking 

in sea water overnight, cleaning, boiling again and 

drying. A local trader evaluated the beche-de-mer 

based on skin colour, cleanliness of gut and skin, and 

resultant product grade. 

Results 

Water quality parameters 

Water temperature was in the range 16.9–33.3 ºC, 

with mean water temperatures between 27.3 ºC and 

27.9 ºC in summer and between 17.5 ºC and 24.1 ºC 

in winter (Figure 2). Dissolved oxygen variation was 

2.9–14.2 ppm, and salinity was mostly between 32 

and 36 ppt. Extreme values of salinity such as 25 and 

38 ppt were occasionally observed. Secchi measurements 

averaged 50 cm. 

Growth rate 

In pond A, sandfish with an initial mean weight 

of 0.9 g reached a mean weight of 325.4 g after 

12 months. Their growth then slowed during the 

cold season, when mean water temperatures were 

between 20.4 ºC and 22.7 ºC (Figure 2). Sandfish in 

pond A reached a final mean weight of 390 g after 

21 months (Figure 3). Mean individual growth rate 

was correlated with water temperature and reached 

a peak of 1.04 g/day in April 2006, when the mean 

water temperature was 27.3 ºC (Figure 2). 

In pond B, the sandfish with a greater initial 

weight of 11.7 g reached a mean weight of 395 g 

after 13 months. Their growth also slowed during 

the cold season when mean water temperature was 

in the range 20.7–22.7 ºC. Excessive development 

of filamentous algae in pond B meant that these 

animals had to be transferred to another pond in 

December 2005. At the time of transfer, survival 

was 73%. The transferred sandfish reached a final 

mean weight of 441 g after 19 months (Figure 3), 

and maximum growth rate was 1.3 g/day in March 

2006 (Figure 2).

Growth rate (g/animal/day) 

1.3 

1.2 

1.1 

1.0 

0.9 

0.8 

0.7 

0.6 

0.5 

0.4 

0.3 

0.2 

0.1 

0 

Jun-05 

Jul-05 

Aug-05 

Sep-05 

Oct-05 

Nov-05 

Dec-05 

Jan-06 

Feb-06 

Mar-06 

Apr-06 

May-06 

Month-year 

Figure 2. Growth of sandfish and mean water temperature in ponds A and B 

Mean weight (g ±SE) 

500 

450 

400 

350 

300 

250 

200 

150 

100 

50 

0 

Jun-05 

Jul-05 

Pond A 

Pond B 

Aug-05 

Sep-05 

Oct-05 

Nov-05 

Dec-05 

Jan-06 

Feb-06 

Figure 3. Mean weight of sandfish in ponds A and B 

106 

Mar-06 

Jun-06 

Apr-06 

Jul-06 

Month-year 

May-06 

Aug-06 

Pond A 

Pond B 

Mean water temperature 

Sep-06 

Jun-06 

Oct-06 

Jul-06 

Nov-06 

Aug-06 

Dec-06 

Sep-06 

Jan-07 

Oct-06 

Feb-07 

Nov-06 

Mar-07 

Dec-06 

30 

29 

28 

27 

26 

25 

24 

23 

22 

21 

20 

19 

18 

17 

16 

15 

14 

13 

12 

11 

10 

Jan-07 

Mean water temperature (ºC±SE)

Maximum growth for sandfish in both ponds during 

these trials was reached after 10–11 months during 

summer (March–April 2006, Figure 2). Growth then 

decreased and ranged from 0.6 to 0.8 g/day for pond A, 

and from 0.7 to 0.9 g/day for pond B (Figure 2). The 

overall average weight gains were estimated to be 0.60 

and 0.77 g/animal/day for ponds A and B, respectively. 

The length–weight relationship of the sandfish 

stocked into ponds A and B (Figure 4) is a power 

curve, as described by Pitt and Duy (2004a). 

Survival and stocking density 

In pond A, survival after 21 months was 69%. 

The final density was 1 animal/m 2 and biomass was 

434 g/m 2. This was well above the level of ~225 g/m 2 

thought to be the limit of growth rates (Battaglene 

1999). Over 3 days in early 2007, 2,222 sandfish were 

harvested (45, 280 and 1,897 animals harvested on 

24 January, 26 January and 15 March, respectively). 

In pond B, final survival was 41% after 19 months; 

high mortalities were observed after the first 6–7 months 

during the 2005–06 summer due to excessive weed 

proliferation (Figure 5), which, in turn, induced high 

water temperature and salinity. At the time of transfer of 

animals, during that summer, the survival rate reached 

73%. The final density was 0.3 animals/m 2 and biomass 

was 147 g/m 2. Over 3 days in early 2007, 668 sandfish 

were harvested (376, 68 and 224 animals harvested on 

10 January, 13 January and 26 January, respectively). 

Wet weight (g) 

600 

540 

480 

420 

360 

300 

240 

180 

120 

60 

107 

Behaviour of sandfish in ponds 

During the full moon in February 2006, when the 

average water temperature was 27.4ºC, an aggregation 

of at least 100 sandfish was observed on the edge 

of pond A (Figure 6). They formed groups of four or 

five individuals (mean weight of 206 g), reaching a 

maximum density of 30 animals/m 2. Pre-spawning 

behaviour, such as rolling movements, was also 

observed. In March 2006, in pond B, an adult male 

(>300 g) spawned in the afternoon. This occurred 

1 day after the first quarter of the moon, when the 

water temperature was 30.7 ºC. 

During winter 2006, 70% of the sandfish were 

buried with a thick layer of mud covering their dorsal 

surface (Figure 7). The average water temperature in 

ponds during this period was 20.5 ºC. 

Birds and their footprints were often observed 

around the ponds. Crabs (e.g. Portunus pelagicus, 

Scylla serrata), indigenous shrimps (Penaeus sp.) 

and fish (Apogon sp., Siganus sp.) were also seen in 

the ponds. During the 21-month grow-out period, 14 

sandfish (22–392 g) with skin lesions were observed 

(Figure 8). The lesions were always on the dorsal surface 

of the animals, and appeared to have been caused 

by predators such as large crabs and birds. 

Another danger is if the pond water level suddenly 

drops. Animals buried near the edge of ponds can be 

trapped, and if they remain out of water for more than 

a few hours, they will eviscerate and die (Figure 9). 

y = 0.1229x 2.6526 

0 

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 

Length (cm) 

R 2 = 0.9867 

Figure 4. The length–weight relationship for cultured sandfish reared in ponds

Figure 5. Weed proliferation in a grow-out pond 

Figure 6. Aggregation of sandfish near pond edge 

108

Figure 7. Buried sandfish 

Figure 8. Sandfish with skin lesions 

109

Figure 9. Trapped and eviscerated sandfish 

Processing into beche-de-mer 

During processing (Figure 10A, B), sandfish were 

gutted by making a small incision on the ventral 

surface to remove the viscera. Initial boiling time was 

about 30 minutes. Drying was done outdoors under 

the sun for at least 1 week, depending on the weather. 

The beche-de-mer from the cultured animals had 

a darker skin colour than the product processed from 

wild sandfish. Most of the cultured beche-de-mer 

was classified as grade A (with some grade Extra-A 

and grade B) with a free-on-board export value of 

€75–77/kg (2007 prices). A negative aspect was that 

cultured animals lost twice as much weight during 

processing compared with wild sandfish. Hence, for 

the grade A beche-de-mer, there were 25 pieces/kg 

instead of 13–15 pieces as found in wild sandfish harvests. 

In spite of this disadvantage, the consistently 

large specimens and high final grade were encouraging 

features for the trader, who normally has to deal 

with variable sizes and fluctuations in numbers from 

local wild sandfish fisheries. 

110 

Discussion 

Although the sandfish in our trials required minimal 

husbandry, some mortality did occur in pond B due to 

high water temperature and salinity. Thus, a combination 

of extreme conditions, such as sudden variation 

of temperature and salinity, handling and transport 

may generate harmful stress leading to loss of stock. 

A key requirement of management is to observe 

some relatively simple measures to minimise the 

risks of stress, such as avoiding extreme variations 

in water temperature, always keeping the animals in 

water in the shade, and not overcrowding the animals 

in containers. Nevertheless, the costs of husbandry 

should be modest because sandfish do not need 

feeding in ponds at medium densities (1.5–3.0 t/ha) 

(Pitt and Duy 2003). 

Stratification of water in ponds due to heavy 

rainfall is to be avoided (Pitt et al. 2001) because it 

can lead to extremely high temperature, low salinity 

and low dissolved oxygen. Sandfish can survive 

salinities as low as 20 ppt, but they are vulnerable 

to anoxic conditions in ponds (Pitt and Duy 2004b). 

Proliferation of filamentous algae can also cause 

similar problems.

A 

B 

Figure 10. Sandfish processing showing: freshly harvested sandfish (A) and initial boiling (B) 

Provided that suitable water conditions can be 

maintained in ponds, the growth rates of sandfish are 

encouraging for farming. Indeed, from grow-out trials 

in shrimp ponds in Vietnam, individual growth rates 

of 2 g/day appear to be possible throughout much 

111 

of the year on a range of substrates (Pitt et al. 2001; 

Pitt and Duy 2003, 2004b). Growth rates in New 

Caledonia were also favourable—at 0.6–1.3 g/day— 

and higher than those in the wild (Hamel et al. 2001). 

They were lower than those in Vietnam, presumably

due to cooler water temperature and lower levels of 

nutrients in the ponds. It appears that lack of nutrients 

in the sediment, high biomass and low water 

exchange resulted in environmental conditions that 

did not favour growth. Management of density was 

not attempted during the grow-out trials because of 

the distance to the site and the fact that a technician 

was not on site at all times. These results suggest that 

survival and growth could be improved substantially 

by regular removal of sandfish to another pond. 

The duration of grow-out to 400 or 600 g can 

possibly be reduced in New Caledonia if juveniles 

are released in summer into ponds with enriched substrates. 

Another potentially promising way to reduce 

the cost of farming sandfish is to find ways to bypass 

the second nursery phase in hatcheries by releasing 

newly settled juveniles directly into ponds. For this 

to succeed, the pond will need to have sediment that 

allows the growing juveniles to bury, and predators 

will need to be controlled. 

This trial showed that sandfish, Holothuria scabra, 

could be reared in earthen ponds. In nature, these 

sea cucumbers live mainly on sandy–muddy subtrata. 

However, the sediment found in shrimp ponds in New 

Caledonia appears to fit the habitat requirements of 

sandfish. 

In New Caledonia the hot season lasts from 

November to mid April, and the coldest season from 

mid May to mid September. In summer, tropical 

depressions and cyclones can also bring heavy rains 

that pose a risk to the farming of sandfish. Without 

any management or intervention, long periods of rain 

can lead to partial or total loss of animals in earthen 

ponds. Future studies should focus on the monitoring 

and management of freshwater influx into ponds 

during these high-risk periods. 

During the hatchery–nursery phase, juveniles of 1 g 

may be obtained after 2–3 months of culture. But we 

must consider that 19–20 months of rearing in ponds 

is necessary for a minimum of 500 g weight, on average, 

for sea cucumbers. Further research should focus 

on improving farming conditions for better growth 

performance and reduced rearing periods. 

Finally, the practice and advantages of alternating 

pond-culture species could also be considered. This 

practice could actually improve sediment quality and 

thus the pond environment. Research on the effects 

of livestock sandfish quality and the structure of the 

sediment basins would be useful. 

112 

References 





Battaglene S.C. 1999. Culture of tropical sea cucumbers 

for stock restoration and enhancement. NAGA – the 

ICLARM Quarterly 22(4), 4–11. 





509–519. 

Conand C. 1990. The fishery resources of the Pacific countries. 

Part 2: holothurians. FAO Fisheries Technical Paper 

272.2. Food and Agriculture Organization of the United 

Nations: Rome. 

Conand C. 1998. Holothurians. In: K. Carpenter and V. 

Niem (eds), ‘FAO species identification guide: the marine 

living resources of the western central Pacific’, Vol. 2, 




The sea cucumber Holothuria scabra (Holothuroidae: 

Echinodermata): its biology and exploitation as Bechede-mer. 



J.X. 1994. Hatchery and culture of the sea-cucumber 


Institute Special Publication No. 57. 

Pitt R. 2001. Review of sandfish and rearing methods. SPC 


Pitt R. and Duy N.D.Q. 2003. To produce 100 tonnes of 

sandfish. SPC Beche-de-mer Information Bulletin 18, 

15–17. 

Pitt R. and Duy N.D.Q. 2004a. Length–weight relationship 

for sandfish, Holothuria scabra. SPC Beche-de-mer 


Pitt R. and Duy N.D.Q. 2004b. Breeding and rearing of 











Purcell S., Gardner D. and Bell J. 2002. Developing optimal 

strategies for restocking sandfish: a collaborative project 

in New Caledonia. SPC Beche-de-mer Information 

Bulletin 16, 2–4.

Ability of sandfish (Holothuria 

scabra) to utilise organic matter in 

black tiger shrimp ponds 

Satoshi Watanabe 1*, Masashi Kodama 2, Jacques M. Zarate 1,3, 

Maria J.H. Lebata-Ramos 3 and Marie F.J. Nievales 4 

Abstract 

Due to frequent viral disease outbreaks, a large proportion of shrimp aquaculture in South-East Asian 

countries has switched from black tiger shrimp (Penaeus monodon) to P. vannamei, an exotic species 

originally imported from Latin America. One of the causes of disease outbreaks is thought to be poor water 

and sediment conditions in the shrimp ponds, which may aggravate disease symptoms. To obtain basic 

information for co-culture methods of black tiger shrimp and sandfish (Holothuria scabra) for possible 

mitigation of shrimp-pond eutrophication and prevention of disease outbreaks, basic laboratory experiments 

were conducted at the Southeast Asian Fisheries Development Center—Aquaculture Department in Iloilo, 

the Philippines. A feeding trial of juvenile sandfish showed that they do not grow well with fresh shrimp 

feed on hard substrate. Another trial indicated that sand substrate enhances the growth of juvenile sandfish 

fed with shrimp feed. A feeding trial using shrimp tank detritus, shrimp faeces and Navicula ramosissima 

(a benthic diatom) as food sources showed that sandfish grew fastest with the faeces, followed by detritus 

and N. ramosissima. Dissolved oxygen consumption and acid-volatile sulfur levels in the shrimp tank detritus 

were reduced by sandfish feeding. This suggests that sandfish are capable of growing with organic matter in 

shrimp ponds, and can bioremediate shrimp-pond sediment. 

Introduction 

The majority of shrimp aquaculture in South-East Asian 

countries has changed from black tiger shrimp (Penaeus 

monodon) to P. vannamei, which is an exotic species 

originally imported from Latin America. The change in 

target species has occurred due to frequent viral disease 

outbreaks, such as white spot syndrome disease, yellow 

1 Japan International Research Center for Agricultural 

Sciences, Tsukuba, Ibaraki, Japan 


2 National Research Institute of Fisheries Science, 

Kanazawa-ku, Yokohama, Japan 

3 Aquaculture Department, Southeast Asian Fisheries 

Development Center, Tigbauan, Iloilo, Philippines 

4 Division of Biological Sciences College of Arts and 

Sciences, University of the Philippines Visayas, Miagao, 

Iloilo, Philippines 

113 

head disease, hepatopancreatic parvovirus disease and 

monodon baculovirus disease (Flegel 2006). Effective 

measures for the prevention of the diseases have not 

been established. Vaccination against these diseases is 

still under development, and it is extremely difficult 

to completely prevent viral intrusion via crustaceans 

and birds that enter outdoor shrimp ponds. In order 

to avoid risk of economic loss associated with mass 

mortality, more farmers culture P. vannamei, which 

can be harvested at a smaller size and earlier than P. 

monodon. However, there is a possibility that P. vannamei 

‘escapees’ may reproduce in the wild and cause 

significant problems to the natural environment. With 

the introduction of P. vannamei, Taura syndrome virus 

and infectious hypodermal and hematopoietic necrosis 

virus have now become problematic (Flegel 2006). 

Thus, it is desirable to establish less risky culture 

methods of P. monodon to revive their production.

While extermination of viruses is difficult, it 

may be possible to suppress disease outbreaks by 

maintenance of optimal water and sediment conditions. 

Anecdotally, it is thought that the disease 

symptoms do not readily manifest in shrimps reared 

in good environmental conditions, despite the presence 

of viruses (Lightner and Redman 1998). As an 

inexpensive technique of environmental control of 

shrimp ponds, co-culture with commercially important 

organisms that have bioremediation capability 

may be a promising approach, and can also provide 

additional income to farmers. Mitigation of shrimppond 

eutrophication by co-culture may also help 

reduce environmental deterioration in areas affected 

by intensive shrimp aquaculture, which has always 

been an issue in South-East Asian countries. To this 

end, the feasibility of co-culture of P. monodon and 

sandfish (Holothuria scabra), a high-value tropical 

sea cucumber, was examined in this study. Since 

sandfish stocks have been heavily depleted in many 

parts of South-East Asia (Carpenter and Niem 1998; 

Hamel et al. 2001; Conand 2004), the co-culture may 

also be beneficial for sea cucumber conservation. 

There are a number of studies on co-culture of sea 

cucumbers with other organisms, such as teleost fish 

(Ahlgren 1998), bivalves (Zhou et al. 2006; Slater and 

Carton 2007, 2009; Paltzat et al. 2008), gastropods 

(Kang et al. 2003; Maxwell et al. 2009) and shrimps 

(Pitt et al. 2004; Purcell et al. 2006; Bell et al. 2007). 

These studies tried to make use of the sea cucumbers’ 

ability to consume particulate organic matter in the 

sediments. Pitt et al. (2004) studied the effects of size, 

stocking density and feeding on the feasibility of coculture 

of P. monodon with H. scabra, and reported 

that co-culture is possible in many situations. However, 

they encouraged further, more rigorous studies due to 

statistical uncertainty in their study. In the present 

study, feeding trials of H. scabra using various types 

of organic matter available in shrimp tanks were 

conducted in order to ascertain an effective feeding 

method for H. scabra in shrimp ponds. The biomitigating 

ability of H. scabra in tanks was also studied. 

Materials and methods 

Feeding trial 1: benthic diatoms and shrimp 

feed 

Juveniles for use in the trials were produced at the 

sea cucumber hatchery of Southeast Asian Fisheries 

Development Center—Aquaculture Department 

114 

(SEAFDEC–AQD). In order to compare the relative 

importance of diatoms and shrimp feed as food 

sources for juvenile H. scabra, feeding trials were 

conducted using Navicula ramosissima (benthic 

diatom monocultured at SEAFDEC–AQD) and 

P. monodon powdered feed (SEAFDEC–AQD 

formula). For each treatment described below, five 

juvenile H. scabra were placed in 60-L fibreglass 

tanks filled with filtered and UV-treated sea water 

with aeration. Sea water was pumped from offshore, 

sand filtered, filtered with 10-µm and 1-µm filters, 

and UV treated before use in the experiments. No 

substrate was added to the tanks. The juveniles were 

fed every 2 days with one of the following diets: 

(1) 1,000 mL N. ramosissima (~6.2 × 10 5 cells/mL); 

(2) a mixture of 500 mL N. ramosissima and 0.5 g 

powdered shrimp feed; (3) 1 g powdered shrimp feed; 

or (4) no feed (negative control). Three replicate tanks 

were used for each treatment, except for the control, 

where only one tank was used. In order to prevent 

growth of natural food and accumulation of contaminants, 

the tanks were cleaned thoroughly and water 

changed completely prior to feeding every 2 days. To 

compare the growth rates between treatments after 

3 weeks, the juveniles’ body length (BL) and weight 

(BW) were measured to the nearest 0.01 mm and 

0.01 g, respectively. To increase size measurement 

accuracy, the juveniles were anaesthetised with 2% 

menthol–ethanol solution (Yamana et al. 2005) and 

blotted dry with paper towels prior to sampling. 

Feeding trial 2: effect of sand on sandfish 

growth 

The effects of the presence of sand substrate on 

the growth of H. scabra were studied. Sand collected 

from the beach in front of SEAFDEC–AQD was 

sieved through 1-mm mesh, washed with fresh water, 

bleached with sodium hypochlorite, washed again and 

sun-dried. The prepared sand was placed in a 60-L 

fibreglass tank (to approx. 5 cm depth), and filtered 

(10-µm and 1-µm) and UV-treated sea water was added 

to the tank. Five H. scabra juveniles were placed in the 

tank and provided with aeration (the with-sand treatment). 

The same number of juveniles was also placed 

in another 60-L tank under the same conditions except 

without sand (the without-sand treatment). The juveniles 

were fed with powdered shrimp feed (0.5 g/tank) 

every day. Water in the tanks was changed 100% every 

2 days but the sand was not washed during the 2-week 

trial. Growth in BL and BW over the course of the 

experiment was compared between treatments.

Feeding trial 3: organic matter from shrimp 

tanks 

Further effects of food types on growth of 

H. scabra juveniles were studied using organic 

matter that should be available in shrimp ponds: 

shrimp faeces, shrimp-tank detritus and N. ramosissima 

(Navicula species are ubiquitous). Faeces and 

detritus were collected from P. monodon tanks at 

SEAFDEC–AQD. The tanks were drained to collect 

the sedimentary detritus, and fresh faeces were manually 

separated from the total detritus using spoons. 

Faeces and detritus were stored at –80 °C until used. 

Juvenile H. scabra were individually placed in 

containers made of PVC pipe (10 cm diameter × 

5 cm length) with both ends covered with 5-mm mesh. 

For each treatment described below, 10 containers 

were placed in each 60-L fibreglass tank with sand 

and aeration. Each container was partially embedded 

in the sand. Juveniles were fed every 2 days 

with the following: (1) 2 g shrimp-tank detritus; 

(2) 2 g shrimp faeces; (3) 430 mL N. ramosissima 

(~ 6.2 × 10 5 cells/mL); and no feed (negative control). 

Two replicate tanks were used for each treatment 

except for the control, where only one tank was used. 

Water was changed 100% every 2 days and sand in 

the tanks was not cleaned. The trial ran for 10 days. 

The BL and BW of all juveniles were measured 

after 10 days. The juveniles were anaesthetised before 

recording the measurements. Carbohydrate concentration 

in the coelomic fluid of the juveniles was measured 

after the size measurements. Coelomic fluid was collected 

with a micropipette though an incision along 

the abdomen, and the carbohydrate concentration was 

measured by a modified phenol – sulfuric acid method 

(Kushwaha and Kates 1981). A 10-µL aliquot of coelomic 

fluid was mixed with 40 µL distilled water, 20 µL 

5% phenol solution and 100 µL concentrated H 2SO 4 in 

2-mL microtubes; vortexed; and incubated in a block 

heater at 80 °C for 10 minutes. Absorbance was read 

at 490 nm against a blank, using a microplate reader. 

Biomitigation of sediment eutrophication 

by sandfish 

In order to examine the ability of H. scabra to 

mitigate sediment eutrophication, two aspects of sedimentary 

organic matter were studied: (1) reduction of 

acid-volatile sulfur (AVS) level in detritus after ingestion 

and excretion by H. scabra; and (2) reduction of 

dissolved oxygen (DO) consumption by detritus after 

ingestion and excretion by H. scabra. 

115 

Holothuria scabra (about 20 cm in BL) were allowed 

to defecate in a bare tank for 2 days, then were separately 

placed in bare 60-L fibreglass tanks (n = 3) with 

aeration, and allowed to feed on shrimp tank detritus 

for 2 days. Their faeces were then collected with a 

spatula. AVS levels in both the faeces and the detritus 

were measured by Hedorotech-S kit (GASTEC Co.) 

About 3 g of both the faeces and detritus samples 

(n = 3 each) were mixed with 330 g filtered sea water, 

placed in sealed Erlenmeyer flasks, shaded with 

aluminum foil, and placed in an incubator at 27 °C. 

A control flask containing filtered sea water was also 

incubated. DO levels were measured every hour with 

a DO meter until DO in one of the treatments was 

depleted. DO consumption rate (mg O 2/g/hour) was 

determined as the largest difference between two 

successive readings. 


Feeding trial 1: benthic diatoms and shrimp 

feed 

Diatoms and epiphytic algae are suggested to 

be important food sources for juvenile H. scabra 

by Battaglene et al. (1999), who hypothesised that 

reduced light decreased growth in H. scabra juveniles 

through lower algal production. Shrimp starter 

feed is also reported to be good food for H. scabra 

(Pitt et al. 2004). Results from these trials confirmed 

that there was no mortality of H. scabra in any feed 

treatment during the 3-week study. However, unlike 

the previous study (Pitt et al. 2004), negative growth 

was observed in H. scabra fed with powdered shrimp 

feed (Figure 1; –0.026 to –0.022 g/day, –0.27 to 

–0.17 mm/day). Positive growth was observed in 

H. scabra fed with a mixture of powdered shrimp 

feed and N. ramosissima (Figure 1), in which 

the growth rates (0.065 to 0.12 g/day, 0.36 to 

0.45 mm/day) were comparable to those of those 

fed only with N. ramosissima (0.036 to 0.12 g/day, 

0.30 to 0.52 mm/day). Thus, powdered shrimp feed 

by itself was found to be ineffective for the growth 

for H. scabra under the rearing conditions used in 

this trial. 

Feeding trial 2: effect of sand on sandfish 

growth 

Battaglene et al. (1999) reported that the growth 

rate and survival of H. scabra juveniles reared on 

sand was higher than those on a hard substrate when

fed with dried powdered algae and natural biofilm. 

Kihara et al. (2009) observed faster growth and 

better survival of Japanese sea cucumber juveniles 

(Apostichopus japonicus) with the presence of sand, 

compared with those provided with no sand, when 

fed with dried powdered algae. Although the effect 

of sand on the survival of juveniles is not consistent, 

sand substrate seems to have a positive effect on the 

growth of sea cucumbers. 

In this study, a similar result was observed. 

H. scabra juveniles provided with powdered 

shrimp feed showed positive growth (0.068 g/day, 

0.25 mm/day) in the presence of sand (Figure 2), 

whereas juveniles reared without sand showed negative 

growth (–0.13 g/day, –0.42 mm/day). The growth 

rate observed in the ‘with-sand’ treatment was smaller 

than that reported for similar sized individuals by 

Pitt et al. (2004), in which shrimp feed and sand 

substrate were used. Nevertheless, the presence of 

sand substrate seems important for feeding and/or 

assimilation of food for H. scabra. Kihara et al. (2009) 

Body length (mm ± SD) 

Body weight (g ± SD) 

70 

60 

50 

40 

30 

20 

10 

0 

10 

8 

6 

4 

2 

0 

(a) 

t = 0 

t = 21 days 

N N N N+S N+S N+S S S S C 

(b) 

t = 0 

t = 21 days 

N N N N+S N+S N+S S S S C 

Figure 1. Mean (a) length (mm) and (b) weight (g) of 

Holothuria scabra juveniles (n = 5) reared 

with: Navicula ramosissima (N); a mixture 

of N. ramosissima and powdered shrimp 

feed (N+S); powdered shrimp feed (S); and 

no feed (C) for 21 days; error bars represent 

standard deviation. 

116 

reported that, although A. japonicus ingested dried 

powdered algae, it did not bring about positive growth 

in the absence of sand. Since faeces were constantly 

observed in the ‘without-sand treatment’ during this 

trial, H. scabra seem to ingest powdered shrimp feed 

without sand. Therefore, sand may assist digestion 

of food particles in the gut of sea cucumbers. It is 

also possible that partially decomposed shrimp feed 

that could not be removed from the sand was more 

readily digestible or assimilable than fresh feed for 

sea cucumbers, which have been shown to have low 

digestive enzyme activity (Yingst 1976). 

Feeding trial 3: organic matter from shrimp 

tanks 

H. scabra juveniles showed positive growth 

when fed with shrimp tank detritus, shrimp faeces 

and N. ramosissima, except in one of the replicates 

of the detritus treatment (Figure 3). The 

growth rate was fastest with the faeces (0.018 to 

0.052 g/day, 0.18 to 0.38 mm/day), followed by 



75 

70 

65 

60 

55 

50 

25 

23 

21 

19 

17 

(a) 

(b) 

t = 0 

t = 14 days 

With sand Without sand 

t = 0 

t = 14 days 

With sand Without sand 

Figure 2. Mean (a) length (mm) and (b) weight (g) of 

Holothuria scabra juveniles (n = 5) reared 

with and without sand substrate in fibreglass 

tanks and fed powdered shrimp feed for 

14 days; error bars represent standard 

deviation.

detritus (–0.021 to 0.026 g/day, –0.26 to 0.29 mm/day) 

and N. ramosissima (0.011 to 0.013 g/day, 0.156 to 

0.158 mm/day). This, together with the result of 

feeding trial 2, indicates that H. scabra can grow in a 

P. monodon pond without additional feeding. Growth 

rates obtained in this trial are comparable with those 

reported by Battaglene et al. (1999), in which diatoms 

and epiphytic algae were fed to H. scabra, but almost 

an order of magnitude slower than those reported by 

Pitt et al. (2004). Therefore, shrimp feed in the presence 

of sand substrate, rather than decomposed leftovers, 

shrimp faeces or naturally occurring micro-algae, 

seems to be suitable for the growth of H. scabra. Yuan 

et al. (2006) reported that the mixed diets of bivalve 

faeces and powered algae showed promising results for 

cultivation of sub-adult Apostichopus japonicus, while 

the sea cucumber fed with powdered algae or faeces 

alone could not obtain the best growth. Holothuria 

scabra may be able to consume fresh leftovers by 



50 

45 

40 

35 

30 

4.5 

4.0 

3.5 

3.0 

2.5 

2.0 

1.5 

(a) 

t = 0 

t = 14 days 

D D F F N N C 

(b) 

t = 0 

t = 14 days 

D D F F N N C 

Figure 3. Mean (a) length (mm) and (b) weight (g) 

of Holothuria scabra juveniles (n = 10) 

reared with detritus collected from Penaeus 

monodon rearing tanks (D); P. monodon 

faeces (F); Navicula ramosissima (N); and 

no feed (C) for 14 days; error bars represent 

standard deviation. 

117 

P. monodon more efficiently, rather than deteriorated 

sludge in the shrimp pond. 

The carbohydrate concentration in the coelomic 

fluid had a significant negative correlation with 

growth in BL (Figure 4; r = –0.30, p < 0.05) and 

BW (r = –0.29, p < 0.05, n = 70). Watanabe et al. 

(2012) found that carbohydrate concentration in the 

coelomic fluid is positively correlated with starvation 

period. Therefore, carbohydrate concentration may 

be correlated with growth rate through nutritional 

condition, which presumably affects the growth rate 

of H. scabra. However, although the correlations 

were significant, the correlation coefficient had small 

values, and carbohydrate concentration values were 

highly variable, especially at low growth rates. Since 

feeding condition or nutritional condition is not the 

only factor affecting growth rate, one should be careful 

in the interpretation of carbohydrate concentration 

when analysing it in relation to growth rate. 

Carbohydrate conc. 

(mg/mL) 

Carbohydrate conc. 

(mg/mL) 

2.5 

2.0 

1.5 

1.0 

0.5 

0 

–1.0 –0.5 0 0.5 1.0 

Growth rate (g/day) 

2.5 

2.0 

1.5 

1.0 

0.5 

(a) 

(b) 

0 

–1.0 –0.5 0 0.5 1.0 

Growth rate (g/day) 

Figure 4. Relationship between growth rate of (a) 

length (mm/day, and (b) weight (g/day) 

and carbohydrate concentration (mg/mL) 

in the coelomic fluid of Holothuria scabra 

juveniles (n = 70) reared with detritus 

collected from Penaeus monodon rearing 

tanks; P. monodon faeces and Navicula 

ramosissima. Linear correlations were 

significant in both graphs.

Biomitigation of sediment eutrophication 

by sandfish 

Dissolved oxygen consumption by faeces of 

H. scabra fed with shrimp tank detritus was 22% 

of that consumed by the shrimp tank detritus alone 

(from 1.0 ± 0.1 SD to 4.5 ± 1.0 SD g O 2/g dry 

wt/hour, p < 0.001, n = 3, t-test) (Figure 5). This 

may be attributable to reduction of organic matter in 

the detritus through assimilation by H. scabra (i.e. 

less organic matter equals less oxygen consumed by 

micro-organisms during decomposition of organic 

matter). Grazing of the brown sea cucumber 

(Australostichopus mollis) reduces total organic 

carbon, chlorophyll a and phaeopigment, as well as 

the chlorophyll a : phaeopigment ratio of sediments 

impacted by green-lipped mussel depositions (Slater 

and Carton 2009). Conversely, it is reported that, 

while H. scabra bioturbate sediments and eat organic 

deposits in tanks with blue shrimp (Litopenaeus stylirostris), 

they did not significantly reduce the organic 

content of the sand in the tanks (Purcell et al. 2006). 

Oxygen consumption 

(mgO /g dry wt/hour ± SD) 

2 

AVS (mg/g dry wt) 

6 

5 

4 

3 

2 

1 

0 

0.8 

0.6 

0.4 

0.2 

0 

(a) 

(b) 

Detritus Faeces 

Detritus Faeces 

Figure 5. (a) Dissolved oxygen consumption rate 

and (b) acid-volatile sulfur (AVS) level of 

detritus collected from Penaeus monodon 

rearing tanks and faeces of H. scabra 

fed with the detritus (n = 3 for oxygen 

consumption rate and n = 1 for AVS level); 

error bars represent standard deviation. 

118 

If this also applies to the detritus derived from 

P. monodon, H. scabra may somehow change the 

nature of organic matter in the detritus so that oxygen 

consumption is reduced. Regardless of the actual 

mechanism, reduction of oxygen consumption is an 

important consequence of H. scabra feeding since 

hypoxia in the sediment and bottom water is a major 

problem in shrimp ponds (Suplee and Cotner 1996; 

Avnimelech and Ritvo 2003). 

AVS level (hydrogen sulfide and iron sulfide 

≈ total sulfur) in the shrimp tank detritus 

(0.67 mg/g dry wt) was reduced by 55% by H. scabra 

(0.31 mg/g dry wt) feeding (Figure 5). Dissimilative 

sulfate reduction by sulfate-reducing bacteria 

(Fenchel and Blackburn 1979) results in the release 

of hydrogen sulfide into the environment, which is 

very toxic to many aquatic organisms (Bagarinao 

and Vetter 1992). Sulfide diffused out of sediments 

into bottom water is quickly oxidised biotically and 

abiotically (Jorgensen 1977); therefore, high sulfide 

levels in the sediment can aggravate hypoxia in the 

bottom water. Thus, AVS reduction in shrimp-tank 

detritus by H. scabra should bring about positive 

effects to the environment of a shrimp pond. Further 

quantitative analysis should be carried out to determine 

the proper stocking density of H. scabra for 

effective biomitigation of a shrimp pond. 

Conclusions 

The series of experiments conducted in this study 

showed that, although more quantitative data are 

needed, H. scabra has potential to biomitigate the 

eutrophication and improve sediment quality in a 

shrimp pond. Studies on the relationship between 

stocking density of H. scabra and the extent of 

biomitigation, as well as relationships between the 

shrimp-pond environment and shrimp disease manifestation, 

should also be carried out. 

Agudo (2006) suggested that, although the availability 

of cultured juvenile H. scabra provides potential 

for farming H. scabra in earthen ponds or sea 

pens, it should not be reared in ponds together with 

shrimp because shrimp prey on H. scabra. Bell et 

al. (2007) reported that co-culture of H. scabra with 

blue shrimp (Litopenaeus stylirostris) is not viable 

due to death and morbidity of H. scabra. Therefore, 

in co-culture with P. monodon, H. scabra should be 

either protected in cages or reared in a separate pond, 

to which shrimp-pond effluents are introduced before 

the water is returned to the shrimp pond. Rotational

culture is another possible approach. Further studies 

to establish practically feasible co-culture methods 

should be conducted. 


The authors are grateful to Joemel Sumbing, Jesus 

Rodriguez, Harold Figurado and Esteban Garibay at 

SEAFDEC–AQD for assistance in sandfish culture 

and laboratory analysis. This study was funded by the 

Japan International Research Center for Agricultural 

Sciences (JIRCAS). 

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119 





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Yuan X., Yang H., Zhou Y., Mao Y., Zhang T. and Liu Y. 

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Establishment and management of 

communal sandfish (Holothuria scabra) 

sea ranching in the Philippines 

Marie Antonette Juinio-Meñez 1*, Marie Antonette S. Paña 1, 

Glycinea M. de Peralta 1, Tirso O. Catbagan 1, Ronald Dionnie D. Olavides 1, 

Christine Mae A. Edullantes 1 and Bryan Dave D. Rodriguez 1 

Abstract 

Sea ranching of sandfish is being piloted as a means to enhance the recovery of depleted natural stocks 

and provide a supplemental source of income for artisanal fishers. Participatory and adaptive approaches 

were employed in the establishment and management of sea ranches to ensure that benefits accrue to both 

the ‘rights-holders’ and other community members. Three pilot sea-ranching sites have been established in 

north-western Luzon, the Philippines. The sites are managed by members of a local association of small fishers 

with the support of the municipal government, which granted limited exclusive-use rights to the sea-ranch 

managers. Each site was delineated into two major use zones: the 1-ha no-take release and nursery area, and 

the 4-ha reserve area. Multiple releases of cultured sandfish juveniles produced from local wild broodstock 

were conducted in the sites. Within 7–10 months, effective spawning populations were established in the 

sea-ranching sites when the density of reproductively mature (>200 g) individuals (ind) exceeded 100 ind/ha. 

Growth and survival rates were variable among sites. At the Bolinao sea ranch, the maximum estimated overall 

density reached 1,119 ind/ha, with an estimated survival rate of 39% after 19 months. Mass spawning of 

sandfish in the sea ranch further demonstrated that community-based sandfish sea ranching can help rebuild 

depleted wild populations. Among the major threats to sustainability are periodic poaching and storms, which 

reduce harvestable biomass and economic returns to the rights-holders. Sea ranching should be integrated 

within a broader fishery management framework to improve the management of sea cucumber fisheries. 

Introduction 

Rehabilitation of overexploited and depleted stocks 

is essential to securing continued production from 

capture fisheries (Bartley and Bell 2008). This has 

become imperative for species that are commercially 

important and heavily exploited, such as sea cucumbers. 

Sea cucumber collection has been an important 

part of the multispecies invertebrate fishery in the 

Indo-Pacific region for over 1,000 years (Conand 




121 

1990). Production of cultured species from hatcheries 

has been undertaken to increase and/or replenish 

yields through restocking, stock enhancement and sea 

ranching. However, despite progress in aquaculture, 

the application of hatchery technologies in fisheries 

management has yet to overcome many challenges. 

These include cost-effective production of juveniles; 

identification of where and when to use such interventions; 

integration of these initiatives with institutional 

fisheries management regimes; monitoring 

the success of interventions; and releasing juveniles 

into the wild in such a way that they survive in high 

numbers (Blankenship and Leber 1995; Bell et al. 

2005, 2006; Lorenzen 2008). Putting these concepts

into practice in a developing-country context to 

harmonise socioeconomic and ecological benefits to 

small fishers was the primary consideration in the 

establishment of communal sandfish sea ranching in 

the Philippines. 

Historical overview of Philippine 

sea cucumber resources and 

fisheries 

The sea cucumber fishery has been and is still an 

important source of livelihood for many of the 

coastal communities in the Philippine archipelago 

(Domantay 1934; Trinidad-Roa 1987; Akamine 

2001). One of the earliest commercial sea cucumber 

fisheries in South-East Asia, dating back over 

200 years, was in Sulu. Sea cucumbers were collected 

by the best pearl divers of the coastal Tausug and 

vinta-dwelling Samal and Badjao communities for 

the Sulu Sultanate. Licence to fish sea cucumbers was 

given by the sultan, while the datus (the local elites) 

commonly led or deployed several hundred fishers in 

fishing fleets (an early sign of fishery management) 

(Warren 1985). 

In the late 18th century, the sea cucumber fishery 

in the southern Philippines developed rapidly as a 

result of trade with Spain, China and Britain (Warren 

1985; Akamine 2001). From 1805 to 1830, dried sea 

cucumbers or trepang were shipped from Sulu to 

Manila twice a year in varying amounts up to 50 t 

(Warren 1985). Manila was also a main trading port 

between the South Pacific region and China (Ward 

1972, cited in Akamine 2001). 

Between 1924 and 1932, the Philippines exported 

an average of 272 t/year of dried sea cucumbers to 

China, British East Indies, Hong Kong and Japan 

(Domantay 1934). Post-World War II records show 

that the Philippines exported only 0.54 t in 1950 

(Montilla and Blanco 1952), 5 t in 1958 (Surtida and 

Buendia 2000) and 12 t in 1970 (Akamine 2002). 

Export volume rapidly increased to over 600 t in 

1978, exceeding pre-war records, and again doubled 

in 1983. Since then, the Philippines has maintained 

a total annual export of no less than 1,000 t, making 

sea cucumbers a major export commodity. 

Although the Philippines is the second-largest 

exporter of tropical sea cucumbers in the world 

(Conand and Byrne 1993), results of a multisectoral 

national forum established that there have been no 

significant efforts to effectively regulate and manage 

122 

the fishery, either at the national- or local-government 

level (Casilagan and Juinio-Meñez 2007). The 

scarcity of useful fishery baseline information in 

most regions is often cited as an obstacle in the 

formulation of a management plan (Gamboa et al. 

2004). Furthermore, resource managers at the localgovernment 

unit level and the national agencies 

generally know very little about the value and status 

of the sea cucumber resources. 

The status of the sea cucumber resources and 

fishery in the municipalities where the pilot searanching 

sites were established is characteristic of 

overexploited fisheries in many parts of the country. 

For example, in the Bolinao–Anda reef system, 

species diversity is high but population densities 

are very low, and the average sizes of sea cucumber 

are below reported sizes at sexual maturity per species 

(Olavides et al. 2010). Fishery-dependent and 

independent studies in the area found 49 species, 

26 of which are being collected and traded (including 

the very low-value species). The catch per unit 

effort in the 1970s–1980s was reported to be over 

100 kg/day, and had declined to less than 1 kg/day in 

2008. Several high-value commercial species such 

as Thelenota ananas and T. anax have been fished to 

local extinction, while the populations of other target 

species, particularly Holothuria scabra and Stichopus 

horrens, are depleted. 

Sandfish sea ranch establishment 

process and management scheme 

One of the highest valued sea cucumber species in the 

Philippines is Holothuria scabra, commonly known 

as sandfish. With the scaled-up juvenile production of 

sandfish (Juinio-Meñez et al. 2012), sea ranching was 

piloted in three coastal municipalities in north-western 

Luzon. The framework, establishment process and 

management scheme for communal sea ranching of 

sandfish were developed to ensure that benefits accrue 

to both the ‘rights-holders’ and other community 

members (M.A. Juinio-Meñez, unpublished data). 

These were also aimed at minimising social conflicts, 

which are inherent in the open-access and multipleuse 

nature of nearshore fisheries in the Philippines. 

The key implementation strategies are: (1) acquisition 

of exclusive communal-use rights for a 5-ha sea ranch, 

(2) increases in the production, and improvement 

in the quality, of hatchery-produced juveniles, and 

(3) regular monitoring to estimate population growth 

and survival in the sea-ranching sites.

Biophysical, social and governance criteria were 

considered in the selection of three sea-ranching 

sites in the provinces of Pangasinan and Zambales, 

north-western Luzon (Figure 1). The biophysical 

requirements included 50–60% seagrass cover, 

sandy–muddy substrate, minimum exposure to 

wave action, and presence of sandfish. Even if the 

biophysical prerequisites had been met, the final site 

selection was based on the presence of an interested 

local fisher association (or a group with experience in 

community-based coastal resource management) and 

a supportive local government unit willing to grant 

preferential-use rights to the sea-ranch managers. 

Community consultations were conducted in the 

potential sites and in neighbouring villages that may 

be affected by restricted access in the sea-ranch area. 

Upon endorsement of the village council, the local 

partners applied for preferential-use rights to manage 

the sea ranch and exclusively harvest all sea cucumbers 

in the site. This was legitimised by an ordinance 

passed by the local legislative body, and the issuance 

of a gratuitous permit by the mayor. The responsibilities 

of the local sea-ranch managers were to help in 

conducting information and awareness campaigns, 

123 

provide manpower in developing and maintaining the 

site, and guard the sea ranch (Figure 2A, B, C, D). 

The sea-ranch rights-holders initially comprised 

12–15 families of fishers per site, with an average 

annual income of US$640–5,600 per household. Each 

of the 5-ha sites was delineated into two major use and 

management zones composed of a 1-ha nursery notake 

zone located at the centre of the sea ranch, and a 

4-ha reserve zone surrounding the nursery zone. Inside 

the no-take zone is a core release area (50 × 50 m), 

where cultured sandfish juveniles were released. 

In addition, 3 × 100 m 2 circular pens were installed 

in the core release area and stocked with juveniles 

to facilitate monitoring of growth and survival of a 

single batch. To minimise disturbance of the released 

juveniles, entry into the nursery zone is restricted to 

release and monitoring activities. In the reserve area, 

boat passage and traditional fishing activities (except 

for any species of sea cucumbers) are allowed with 

permission from the sea-ranch managers. 

Hatchery-produced juveniles (>3 g) were released 

in multiple batches, with varying numbers of individuals 

(ind) per batch. Juveniles were released individually 

by pressing their bodies lightly into the surface 

Figure 1. Map of the three sea-ranching sites in north-western Luzon, the 

Philippines: (1: Barangay Victory, Bolinao, Pangasinan; 2: Barangay 

Sablig, Anda, Pangasinan; 3: Panglit Island, Masinloc, Zambales)

Figure 2. Regular activities of sea-ranch managers. A: Conducting information 

and education activities for local communities and site visitors. B: Site 

development (e.g. delineation and pen construction). C: Release of 

hatchery-produced sandfish juveniles. D: Guarding the sea ranch. 

E: Periodic monitoring. F: Mass harvest and processing 

of the sediment, partially burying them, to reduce the 

risk of predation. Stratified belt transect surveys in 

different areas of the sea ranch were conducted with 

local partners every 3–4 months to estimate survival 

and growth. Population densities, abundance and 

biomass of sandfish were also estimated. The results 

of the surveys were discussed with the sea-ranch 

managers to assess the status of the sandfish in the 

sites and schedule harvests. The managers processed 

the harvested sandfish themselves (Figure 2E, F), and 

sold their products to sea cucumber wholesalers or 

exporters in Manila. A comparison of key information 

on the management and monitoring surveys 

in the three pilot sea-ranching sites is presented in 

Table 1. 

124 

Lessons learned and insights 

A viable spawning population can be 

established and maintained in a sea ranch 

Growth and survival of sandfish in the sea-ranch 

sites were widely variable. From an average release 

size of 5–7 g, sandfish reached an initial size of 

sexual maturity of about 180 g within 7–10 months. 

The density of sandfish in the sea ranches increased 

rapidly in the first year of operation, with maximum 

densities across the three sites in the range 

302–1,119 ind/ha (Table 1). The highest estimated 

survival was 39% in the Bolinao sea ranch after 

19 months, with density reaching 1,119 ind/ha. This 

is over 400 times the density of the wild population 

in the Bolinao–Anda reef system, which is only

about 6 ind/ha (Olavides et al. 2010). This density 

approaches that of a relatively unexploited natural 

population of 2,900 ind/ha reported from Papua New 

Guinea (Shelley 1985). In contrast, the maximum 

survival estimate in the two other sites was only 14% 

(Table 1). 

More importantly, within 10 months after the first 

release of juveniles, the density of reproductively 

mature (>200 g) individuals exceeded 100 ind/ 

ha. The highest density of reproductively mature 

sandfish was 499 ind/ha after 19 months, comprising 

over 40% of the sandfish in the Bolinao sea 

ranch. Synchronous spontaneous spawning was 

also observed in the Bolinao and Anda sites on 23 

February 2010 (Olavides et al. 2011). Prior to and 

after this mass spawning event, the sea-ranch managers 

observed sandfish exhibiting spawning behaviour, 

clearly demonstrating that a viable spawning population 

has been established in these sites. 

Typhoons and poaching are major threats 

to economic viability 

The modal size (total weight) of sandfish in 

the Bolinao sea ranch decreased drastically after 

125 

protracted periods of heavy rainfall and strong waves 

brought about by two consecutive typhoons during 

September and October 2009 (Juinio-Meñez, unpublished 

data). There was a decrease of about 70% in 

the estimated total biomass in the sea ranch—from 

1,100 kg to 347 kg over a 7-month period—after 

the typhoons (6th to 8th monitoring periods). The 

estimated harvestable biomass (i.e. sandfish >320 g) 

prior to the typhoon in July 2009 was about 188 kg. 

Four months after the typhoon, there was no harvestable 

biomass. The negative impact of typhoons on 

the growth of sandfish may be attributed to drastic 

changes in environmental factors and habitat modification. 

The heavy rains may have caused significant 

exposure to suboptimal salinity levels that stressed 

the sandfish—preliminary laboratory experiments 

showed that sandfish ceased to feed at around 20 ppt 

salinity (J.R. Gorospe, unpublished data). Further, 

it was also observed that, after the typhoon, sediment 

in the sea-ranching area became coarse, with 

abundant coral rubble on the surface. The progressive 

decrease in weight of individual sandfish months later 

indicates that the strong typhoons decreased sediment 

quality in the sea ranch. 

Table 1. Management and sandfish population data in the three pilot sea-ranching sites in north-western Luzon 

Bolinao, 

Pangasinan 

Rights-holder Association of small 

fishers 

Location of sea-ranching sites 

Anda, 

Pangasinan 

Co-managed by 

representatives of 

village council and a 

people’s organisation 

Masinloc, 

Zambales 

Members of the 

marine protected area 

council 

Date of first release Dec 2007 Dec 2008 May 2009 

Total number of juveniles releaseda 14,300 

(10 releases) 

Mean weight (g) 

(size range 3–20 g) 

Maximum weight of sandfish harvested 

(g) 

Estimated density 

(ind/ha) after 16–18 months 

Highest estimated density of individuals 

>200 g (ind/ha) 

Range of estimated survival of released 

juveniles (%) during the first six 

monitoring periods 

Highest estimated biomass (kg) in entire 

sea ranch (5 ha) 

a Excluding juveniles released in the pens inside the sea ranch during the first year 

18,749 

(8 releases) 

21,272 

(6 releases) 

7.0 ± 4.7 5.8 ± 2.8 5.5 ± 1.9 

630 560 500 

1,119 86 90 

499 224 116 

19–39 2–13 2–14 

1,100 419 292

Aside from natural disturbances, poaching reduces 

the potential economic returns to the sea-ranch 

rights-holders. All the sites have a round-the-clock 

rotational guarding scheme agreed upon by the 

sea-ranch managers to minimise opportunity costs 

(i.e. 2–3 days a month per household). The income 

share from the sea ranch was proportional to the 

time and effort invested by each member household. 

Consistency and commitment of members to adhere 

to guarding schedules varied among sites. Even in 

Bolinao, where the management has been exemplary, 

incidences of successful poaching have occurred. No 

major typhoon has affected the two other sites, and 

yet estimated survival rates in these sites were lower 

(Table 1). This may be due, in part, to poaching incidences 

of sandfish within the sea ranch. Poaching is a 

given socioeconomic constraint in open-access areas 

with many poor subsistence fishers. Thus, governance 

mechanisms to mitigate and manage social conflicts 

are crucial to the success of sea-ranching efforts. 

Another factor that affects the harvestable biomass 

is movement of sandfish outside the sea-ranch area. 

This is determined by various environmental factors 

that affect habitat quality (including incidence of 

natural disturbances such as typhoons), and needs to 

be investigated more closely in the future. 

Sea ranching is part of an integrated 

fishery management framework 

Communal sandfish sea ranching is a model that 

could be adopted to harmonise the need to rebuild 

depleted populations and, at the same time, provide 

economic incentive for rights-holders who invest 

in managing the areas. The community-managed 

5-ha sea ranch demonstrates that release of sandfish 

in suitable and well-managed sites can establish 

viable spawning populations that should contribute 

to rebuilding depleted fishery stocks. An effective 

spawning population in the sea ranch can be maintained 

while optimising economic returns through 

programmed releases of juveniles and selective harvesting 

of sea cucumbers (e.g. >320 g). Harvesting 

animals larger than the average size at sexual maturity 

(~200 g) also increases economic returns since 

bigger sandfish fetch a higher price in the market. 

However, sandfish sea ranching will not be feasible 

in many situations; for example, where there is no 

supply of cultured juveniles, in habitats that are not 

suitable for H. scabra, and where risks from natural 

disturbances and poaching are very high. In the 

Philippines, where management of nearshore waters 

126 

is under the jurisdiction of local government units 

(LGUs), local-level management systems such as 

partnerships between small-scale fishers and LGUs 

are important. To promote sustainability of severely 

exploited and unmanaged multispecies sea cucumber 

fisheries in the country, the important components of 

an integrated fishery and sea-ranching management 

system include: implementation of a registry and 

permit system for fishers, processors and traders that 

is consistent with the provisions of national fisheries 

codes; minimum size limits for harvest and trade; and 

community-managed reserves such as the communal 

sandfish sea ranches discussed here. 


The establishment of the pilot sea-ranching area for 

sandfish was funded by the Australian Centre for 

International Agricultural Research (ACIAR), with 

complementary support from the Department of 

Science and Technology (DOST) of the Philippines. 

This work would not have been possible without 

the active engagement and wisdom of our primary 

research and development partners—the sea-ranch 

managers: Samahan ng mga Maliliit na Mangingisda 

ng Victory, Inc. (SMMVI); Sablig Barangay Multisectoral 

Association (SBMA) and its barangay 

council; Marine Protected Area Management 

Council of Panglit Island, Research and Development 

Committee; and the local government units of 

Bolinao and Anda in Pangasinan and Masinloc, 

Zambales. 

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Philippines: continuities and discontinuities. Tropics 

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enhancement, and sea ranching: arenas of progress. 

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Maldives sea cucumber farming experience 

Beni G.D. Azari 1* and Grisilda Ivy Walsalam 

Abstract 

With recent technological developments and the increasingly intensive interest in tropical sea cucumber 

farming, it is an opportune time to review the existing strategies of the first successful commercial hatchery 

in the Republic of Maldives (the Maldives). This may help to understand the success of the hatchery and 

grow-out operations. This paper analyses the strategies used in the production and grow-out of the commercially 

important sea cucumber Holothuria scabra, and their effects on the local communities and the 

environment in the Maldives. Holothuria scabra has been cultured in the Maldives since 1996. Hatchery 

production techniques consistently produce high-quality juveniles. When the juveniles reach 2–3 cm in size, 

they are transferred to nearby company-owned atoll lagoons for further growth. The sea cucumber grow-out 

period varies between 12 and 18 months in these waters. In addition to the company’s own sea cucumber 

grow-out operation, considerable quantities of juveniles are grown, with similar grow-out periods, by contract 

growers and villagers from the nearby islands. When the sea cucumbers are fully grown (350–425 g), the 

local growers sell them back to the company and are paid a management fee according to the duration of 

care and quantity of the product. The participation of the local community and village groups is one of the 

reasons for the ongoing success of sea cucumber culture in the Maldives. Sea cucumber hatchery production 

is a profitable operation in the Maldives, even though the cost of production per juvenile is higher due to the 

remote location and associated higher energy and transportation costs. 

1 Sea Cucumber Consultancy, Hervey Bay, Queensland, 

Australia 


128

Sandfish (Holothuria scabra) production 

and sea-ranching trial in Fiji 

Cathy A. Hair 1* 

Abstract 

There is presently enormous interest in the Pacific islands region in restoring depleted sea cucumber fisheries 

with hatchery-produced juveniles. The Australian Centre for International Agricultural Research funded 

projects in Fiji to transfer technology for culturing and sea ranching of sandfish (Holothuria scabra, known 

locally as ‘dairo’). Two hatcheries that respectively produce blacklip pearl oyster and penaeid shrimp were 

successfully used to culture sandfish. Government aquaculture officers and private-sector hatchery technicians 

were trained in sandfish production methods. Successful spawning and rearing to the small juvenile stage 

were carried out at both hatcheries but, due to factors such as cyclones and equipment failure, only one of the 

hatchery runs produced about 500 large juveniles for a release trial. An extensive seagrass bed on a shallow 

sand flat in front of Natuvu village, Vanua Levu, met the criteria for suitable habitat for sea ranching, and 

the community was committed to the research. The juveniles were released into four 100-m 2 sea pens (two 

pens each of small and large juveniles, 1–3 g and >3–10 g, respectively). Survival after 6 months was around 

28% overall (23% for small and 33% for large sandfish). 

The Natuvu community ceased harvest of sandfish from the wild prior to the project starting, and also 

declared a marine protected area (MPA) around the sea-ranching site. An unanticipated benefit of the project 

was an increase in other valuable sea cucumber species in their MPA, which were harvested for a one-off 

community fundraising event. 

Introduction 

There is enormous interest in the Pacific islands region 

in the potential for restoring depleted sea cucumber 

fisheries with hatchery-produced juveniles. This 

report describes Australian Centre for International 

Agricultural Research (ACIAR)-funded projects in 

Fiji to transfer technology for culturing and sea ranching 

of sandfish (Holothuria scabra, known locally as 

‘dairo’). Sandfish are a traditional food item (Figure 

1) and are restricted by legislation to collection for 

domestic consumption. However, Fisheries regulations 

are ambiguous—on one hand stating that sandfish are 

reserved for domestic markets, and on the other setting 

export limits for them. Hence, export-driven overfishing 

of sandfish has occurred in recent years. 

1 James Cook University, Townsville, Queensland, Australia 


129 

Sandfish is one of the few high-value sea cucumber 

species that can be reliably cultured (Battaglene 

et al. 1999; Raison 2008). Two hatcheries that 

normally produce other invertebrate species in Fiji 

were involved in the production of larval and juvenile 

sandfish: a private-sector blacklip pearl oyster 

(Pinctada margaritifera) hatchery and the government 

penaeid shrimp hatchery. One of the uses for 

cultured sandfish juveniles is sea ranching—the 

release of hatchery-produced juveniles into unenclosed 

coastal environments where they are allowed 

to grow to commercial size and later harvested by 

an individual or group in a ‘put-and-take’ operation 

(Bell et al. 2008). However, although hatchery 

techniques for sandfish are well established, the value 

of the final product must be weighed up against the 

cost of producing the juveniles, the subsequent 

growth rates and the survival of sufficient numbers 

to commercial size. Unfortunately, there is limited

Figure 1. Sandfish prepared as a traditional Fijian 

meal 

information on the economic viability of sea ranching 

using cultured juveniles. 

Fiji had several factors in its favour as the location 

for a Pacific-region sandfish sea-ranching trial. 

Importantly, the national government, the private 

sector, non-government organisations (NGOs) and the 

University of the South Pacific (USP) agreed to cooperate 

in the trial research. Many coastal communities 

were also interested in this species. Traditional marine 

tenure and control in the form of qoliqolis (traditional 

fishing-rights areas) provides good security for cultured 

sandfish during trials. In addition to longstanding 

customary management practices, there has been 

a trend in recent years for the traditional owners of 

many qoliqolis in Fiji to develop management plans 

in conjunction with the Fiji Fisheries Department and 

NGOs. Such plans often include the setting aside of 

a marine protected area (MPA) as a ‘no-take’ zone 

within the qoliqoli. These managed areas provide the 

perfect opportunity for trials on the feasibility of sea 

ranching of sandfish. The village involvement also 

improves the chances of development of a management 

framework for sea ranching. 

There were two major goals of the project: 

1. to transfer technology for sea cucumber production, 

release techniques and post-release monitoring 

to government and private-sector technicians 

2. to conduct trials of sea ranching of sandfish in a 

Fijian community qoliqoli to obtain information 

on juvenile sandfish growth and survival; assess 

social, technical and economic feasibility; and 

look at the implications for management options 

for sea ranching as a village livelihood. 

130 

Methods 

Transfer hatchery and juvenile grow-out 

technology 

Study sites and facilities 

The first phase of the technology transfer component 

was carried out between May 2008 and April 

2010 at Savusavu (Figure 2) on Vanua Levu, the 

second largest Fijian island (Hair et al. 2011a). The 

second phase was carried out between October 2010 

and January 2011 at Galoa on Viti Levu, the largest 

island of Fiji (Figure 2). Both sites had hatchery 

facilities but neither was set up for sea cucumber 

aquaculture, so systems were modified and new gear 

provided where necessary. 

In Savusavu, the pearl oyster hatchery of J. Hunter 

Pearls was used (Figure 3; Table 1). The hatchery had 

the essential resources of power, seawater supply and 

treatment capacity (i.e. UV-sterilisation and filtration 

to 1 µm) and aeration. Importantly, it also had a microalgae 

production facility, since several species are 

routinely cultured to support pearl oyster spat production. 

Four 1,600-L conical-based tanks were available 

for sea cucumber larval rearing. A reliable source of 

broodstock was available at Natuvu village, about 

2 hours’ drive (by car or boat). In order to support sandfish 

aquaculture, we used available tanks and hatchery 

resources, built temporary raceways, and negotiated the 

use of a local seawater pond for holding broodstock and 

for hapa net trials for juvenile grow-out. 

In Viti Levu, the Fiji Fisheries Department shrimp 

hatchery at Galoa (Figure 4; Table 1) was used. This 

hatchery also had town power with a backup generator, 

treated sea water and aeration. Five conical-based 

300-L tanks and two 1,000-L flat-based tanks were 

available for larval rearing. Various raceways and 

large tanks were also made available for holding 

broodstock, water storage and so on. A spawning 

tank was created by cutting down a 1,000-L rainwater 

tank and installing a central standpipe. There was no 

micro-algae production at the hatchery but carboys of 

algae were supplied by USP and stored for 2–3 days 

at a time in an air-conditioned room fitted with lights. 

There were reports of adult sandfish being available 

locally, but we used Natuvu broodstock again because 

we planned to release juveniles back at that location. 

Galoa also had three saltwater earthen ponds used 

for shrimp culture, one of which was allocated for 

sandfish juvenile grow-out.

Figure 2. Map of Fiji showing general location of the two study site areas, Savusavu on Vanua Levu (red box) and 

Galoa on Viti Levu (black box) (map courtesy of Secretariat of the Pacific Community) 

Figure 3. The J. Hunter Pearls blacklip pearl oyster hatchery at Savusavu, Vanua Levu 

131

Table 1. Summary of features and resources available at the two hatcheries used to produce sandfish in Fiji 

J. Hunter Pearls Fisheries Department 

Location Savusavu, Vanua Levu Galoa, Viti Levu 

Core production species Blacklip pearl oyster (Pinctada 

margaritifera) 

Water supply Direct from the sea, filtered to 1 µm, 

UV-treated 

132 

Penaeid shrimp (Penaeus monodon) 

and freshwater prawn (Macrobrachium 

rosenbergii) 

Pumped into large, open storage tank from 

the sea, filtered to 1 µm, UV-treated 

Spawning tank Modified fish transport box (1 m 3) Modified circular rainwater tank 

(0.7 m 3) 

Larval rearing tanks 4 × 1,600-L conical-based fibreglass 5 × 300-L conical-based fibreglass, 

2 × 1,000-L flat-based plastic 

Live micro-algal feed Chaetoceros muelleri, T. ISO a, 

Proteomonas sulcata. Nitzschia 

closterium: produced on demand on site 

Primarily T. ISO a, with small quantities 

of C. muelleri and N. closterium: supplied 

from Suva by University of the South 

Pacific in carboys when available 

Power Town power, no backup Town power, with backup generator 

Broodstock source Natuvu, Vanua Levu (2 hours transport by 

boat and car) 

Natuvu, Vanua Levu (24 hours transport 

by car and ferry) 

Broodstock maintenance Pond/sea Large concrete tank (~6,000 L) 

Juvenile rearing 

a T.ISO = Tahitian Isochrysis sp. 

2 × 2 m improvised raceways (built of 

coconut logs and tarpaulins) 

Bag nets in earthen pond 

Figure 4. Fiji Fisheries Department penaeid shrimp hatchery at Galoa, Viti Levu, showing earthen pond in the 

foreground

Broodstock 

All broodstock for hatchery production in 

both Savusavu and Galoa were collected from the 

Savusavu area, predominantly around Natuvu. This 

was important to ensure that juveniles released into 

the Natuvu qoliqoli were the same genetic stock as 

the existing wild stocks (Purcell 2004). Broodstock 

were usually collected on a rising tide, the time 

when local fishers claimed they were less likely to be 

buried. Depending on the time of collection, broodstock 

were either left in a holding pen until ready 

for packing and transport, or packed directly on the 

boat. They were always transported with one large or 

two smaller individuals in a plastic bag containing 

one-third sea water and two-thirds oxygen. 

In the initial runs at the J. Hunter Pearls hatchery, 

broodstock were held in a pond in Savusavu between 

runs. However, due to poor condition of broodstock 

and losses of animals, we moved to a system where 

sandfish were collected for spawning and returned to 

the sea. At Galoa, a large, indoor cement tank with 

a 10-cm layer of sand in the bottom was used. The 

sand was replaced fortnightly, and water exchange 

and feeding occurred on alternate days. 

Larval and juvenile production 

Spawning of sandfish generally followed methods 

developed by the WorldFish Center (WorldFish) 

(Agudo 2006). Spawning induction employed a combination 

of stresses including (in order): (1) drying 

out a group of 30–40 broodstock for half an hour; 

(2) immersing them in a warm bath for 1 hour (~5 °C 

above ambient water temperature); (3) immersing 

them in a bath of Spirulina for 1 hour; and (4) placing 

them in clean water at ambient temperature until 

spawning occurred. Spawning males were removed 

from the spawning tank after they had each released 

sperm for some minutes. Spawning females were left 

until it was obvious that no more egg releases would 

occur. After all broodstock were removed, eggs were 

left in the tank for at least half an hour and were 

monitored to observe cell division. To minimise the 

incidence of polyspermy, the spawning tank was put 

on flow-through after several males had spawned, 

then eggs were siphoned into an 80-µm egg-washing 

basket and rinsed further. Larval rearing tanks were 

stocked at 0.3 viable eggs/mL. 

At Savusavu, from day 2 after fertilisation, early 

auricularia larvae were fed daily with live microalgae 

(primarily Chaetoceros muelleri and T. ISO (Tahitian 

Isochrysis sp.), with small amounts of Proteomonas 

133 

sulcata). Feeding rates ranged from 20,000 cells/ 

mL at day 2 up to 40,000 cells/mL by around day 

10 (Agudo 2006). Small amounts of Nitzschia 

closterium, a benthic diatom used for conditioning 

settlement plates and feeding early juveniles (Agudo 

2006), were also produced, but this species was difficult 

to mass culture and not available routinely. 

At Galoa, a varied live micro-algae diet was 

difficult to obtain: USP provided carboys of T. ISO 

and occasionally small quantities of C. muelleri 

and N. closterium. To make up for the shortfall in 

live feed, the larvae were fed Reed Mariculture’s 

Instant Algae® (Shellfish Diet 1800®) (Figure 5) at 

the same ration as for live micro-algae. This commercially 

available diet is composed of a mixture of 

Isochrysis (30%), Tetraselmis (20%), Pavlova (20%) 

and Thalassiosira weissflogii (30%), and was used 

successfully as the primary diet for sandfish larvae 

for the first time in Fiji (Hair et al. 2011b). 

At both hatcheries, one-third of the tank was 

exchanged with treated sea water daily from day 

2 onwards. Larvae were monitored daily through 

all larval stages (i.e. length measurement, density 

estimates, observations on condition, activity level 

and malformation). Once doliolaria larvae were 

observed, signalling that settlement was imminent, 

conditioned plates were placed in the tanks. Because 

we were unable to reliably and consistently condition 

plates with live diatoms, we employed the technique 

of Duy (2010) and used perspex plates painted with 

a Spirulina paste (Figure 6). These plates remained 

in the larval tanks until transfer of juveniles to raceways 

4–6 weeks after spawning. Live C. muelleri and 

Figure 5. Instant Algae—a commercially available 

diet used to raise sandfish larvae

Figure 6. Plates coated with Spirulina being placed 

in a larval rearing tank at Galoa 

T. ISO, with small amounts of Algamac 2000 (Biomarine 

Inc.) and Spirulina were added to the tanks 

to feed pentactula and early juveniles (Agudo 2006; 

Duy 2010). At Galoa, where the live algae supply was 

unreliable, instant algae was also used to supplement 

the diet of small juveniles (Hair et al. 2011b). 

Juveniles at both hatcheries were transferred from 

the larval rearing tanks 4–5 weeks after spawning. At 

Savusavu, strong tidal flushing caused low productivity 

in the only available pond, and juvenile grow-out 

was unsuccessful in this environment. Therefore, the 

juveniles were transferred to a bare 4-m 2 raceway 

inoculated with N. closterium at the J. Hunter Pearls 

hatchery. They were moved later to a second 4-m 2 

raceway with sand, and fed with shrimp feed. At 

Galoa, early juveniles were transferred from larval 

rearing tanks directly into 2 × 2 × 1 m bag nets in a 

pond (1-mm mesh), as recommended by Duy (2010). 

134 

Trial sea ranching 

Study site 

The trial sea ranching was carried out in the 

qoliqoli of Natuvu village (Wailevu district), near 

Savusavu (Figure 1). A qoliqoli is a traditionally 

managed fishing area under communal ownership 

that is fished for subsistence by the owners, and can 

also be fished commercially by both owners and nonowners 

(with the owners’ permission). Natuvu village 

was selected after assessing several potential sites. It 

fulfilled a number of key criteria, namely: 

• It had good physical microhabitat based on criteria 

developed by Purcell (2004) (Figures 7, 9a). There 

was an extensive seagrass meadow (approx. 750 m 

long parallel to shore by 500 m wide), characterised 

by a diverse invertebrate fauna (several species 

of sea cucumber, sea stars, urchins, sponges, 

crabs, ascidians, worms etc.) as well as numerous 

sandfish of small to medium size. The substratum 

was sandy–muddy sediment of moderate softness 

(i.e. it was possible to easily push fingers into the 

sediment but not the whole hand). At low tide the 

water depth was 0.2–2.5 m. It had 40–70% seagrass 

cover (primarily Syringodium isoetifolium, 

with a small amount of Halodule uninervis), and 

we graded the area as good to very good. 

• There was minimal freshwater discharge into the 

area. There was some flood risk, but only likely 

during extreme events (e.g. heavy rain associated 

with cyclones). This can be considered a risk 

anywhere in the tropics. 

• There was strong community interest in the 

research—in fact, sandfish collection was banned 

in the months leading up to the research team’s 

visit to Natuvu in order to ‘attract’ research. 

• The village is located on the seashore directly in 

front of and in direct line of sight of the seagrass 

bed. This meant that good security could be provided 

for the released juveniles as they grew to 

commercial size. The site also allowed convenient 

access to the juveniles for monitoring, cage maintenance 

and so on. 

• There were stocks of adult-sized sandfish in the 

surrounding qoliqoli that were available to be 

used as broodstock. This meant that any juveniles 

produced would be released into the same area as 

their parents, which ensured an environmentally 

responsible approach resulting in least genetic 

modification of the wild stocks at the release site 

(Purcell 2004; SPC 2009).

Figure 7. Natuvu sandfish release habitat with resident wild sandfish 

• The village was located about 2 hours by car or by 

car and boat from the J. Hunter Pearls hatchery. 

This proximity made it easy to transport animals 

from Natuvu to the hatchery (i.e. broodstock) or 

from the hatchery to Natuvu (i.e. broodstock return 

or juveniles for release). 

Once the preferred site was selected, negotiations 

were conducted with the qoliqoli owners on how 

the research project would proceed. We also made 

an agreement on who would own any sandfish that 

reached commercial size during the project. 

Pen construction, release and monitoring 

Construction of the pens was a community undertaking 

(Figure 8) and was completed over 2 days prior 

to the release in May 2009. Four circular 100-m 2 pens 

were deployed in the seagrass bed. The pens were 

made of 3-mm black plastic oyster mesh. Each stood 

30 cm above and 10–15 cm below the substratum, to 

reduce the chance of juveniles burying and escaping 

under the sides. The pen sides were reinforced with 

metal posts (Figure 8). 

Release of juveniles into the seagrass bed at 

Natuvu was carried out according to the methods 

recommended by WorldFish and based on studies 

carried out in New Caledonia (Purcell and Eeckhaut 

2005; Purcell et al. 2006a; Purcell and Simutoga 

2008; Purcell and Blockmans 2009). Juvenile sandfish 

were marked by immersing them in a tetracycline 

solution (100 mg/L) for 24 hours, 1 week prior to 

release. They were then returned to the sand raceway 

135 

to recover. At the time of marking, however, the juveniles 

were stunted, and we suspected that marking 

would not be successful because spicules must be 

in the growing phase in order to take up the fluorochrome 

stain (Purcell et al. 2006b). Prior to packing 

and transport, individual animals were examined for 

any lesions or obvious health problems (Purcell and 

Eeckhaut 2005). 

At the hatchery the juveniles were divided into 

small (1–3 g) and large (>3–10 g) size classes, 

counted and packed into plastic bags with water 

and oxygen. Two size classes were used because 

half of the available juveniles had not reached the 

optimal release size of >3 g (Purcell and Simutoga 

2008). Furthermore, we were releasing into quite 

different habitat to that used by WorldFish researchers, 

who determined a 3-g minimum—the Natuvu 

Syringodium seagrass bed presented an opportunity 

to test the recommendation of ideal release size. 

At the release site, two 1 × 1 m hapa nets (~1-mm 

mesh) were staked out in the seagrass beds near the 

pens. Small juveniles were placed in one hapa and 

large juveniles in the other, and left overnight to 

acclimatise. The next day the project staff, wardens 

and other community members retrieved the juveniles 

and individually ‘planted’ the sandfish inside 

the pens by forming a small trench with a finger and 

placing the animal inside. Individuals in a subsample 

of released juveniles were marked with numbered 

pegs and checked at regular intervals in the 24 hours 

following release in order to observe behaviour.

Monitoring by project staff and community 

wardens was carried out 3 months after the release 

(August 2009) and then at approximately 2-monthly 

intervals until the conclusion of the study (April 

2010) (Figure 9). On each occasion, the number of 

animals in each pen was counted, and their length 

and width measured. The length–width data were 

used to calculate weight using a formula developed 

by Purcell and Simutoga (2008). Prior to release and 

at the first two monitoring times, skin samples of 

released sandfish were taken and preserved to check 

if they were marked. The skin samples were checked 

using a fluorescent microscope. 

Results 

Transfer hatchery and juvenile grow-out 

technology 

Broodstock 

Figure 8. Project staff (Fiji Fisheries, University of the South Pacific, James Cook 

University) and community helpers constructing one of four sea pens 

in Natuvu qoliqoli seagrass bed in May 2009 

Wild broodstock were mostly collected from 

Natuvu, although a small number was collected from 

other locations near Savusavu (Table 2). Minimum 

broodstock size was 250 g. 

Between spawning runs at the J. Hunter Pearls 

hatchery, sandfish broodstock were held in a pond 

near Savusavu, but average size decreased while 

they were held there. This may have been due to 

sub optimal pond conditions or poaching of large 

136 

animals. Consequently, broodstock were not kept in 

the pond for the last 6 months of the project; instead, 

wild broodstock were collected for spawning and 

then returned to the sea afterwards. 

Broodstock were kept in tanks at Galoa hatchery 

but became stressed, diseased and then died after 

problems with the seawater pump, which meant that 

water exchange did not occur for more than a week. 

Hatchery production to early juvenile stage 

Between November 2008 and March 2010, five 

hatchery runs were undertaken at Savusavu. Each run 

involved multiple spawning attempts with at least 30 

animals. Gamete release from males and females, egg 

fertilisation and larval production were achieved on 

every run. However, only two of the runs resulted 

in settlement, and only one run produced substantial 

numbers of juveniles: 1,500 small juveniles (from 

640,000 stocked eggs) were transferred to raceways 

for further grow-out in February 2009. Of these, 500 

progressed to 1–10-g juveniles, to be used for the 

sea-ranching trial at Natuvu. 

Multiple spawning attempts using 30–40 broodstock 

individuals were carried out during a single 

hatchery run at Galoa in November 2010. Spawning 

occurred, fertilised eggs were produced and larvae 

were reared successfully to settlement. After 7 weeks, 

5,300 small juveniles (from 600,000 stocked eggs) 

were transferred to three bag nets in the pond for

Figure 9. Sandfish in a pen (left), and project staff and community warden measuring sandfish (right), Natuvu 

further grow-out. They reached a mean individual 

weight of ~0.6 g and ~ 2 cm length at 10 weeks of 

age. However, breakdown of water pumps, freshwater 

influx into the pond and insufficient maintenance of 

the bag nets resulted in total mortality of the juveniles 

at 11 weeks (4 weeks after transfer to the pond). 

Trial sea ranching 

Survival and growth of sea-ranched juveniles 

The release was carried out on 18 May 2009: 105 

large juvenile sandfish were placed into each of two 

pens (A, C), and 143 small sandfish were placed 

into each of two pens (B, D). Observations made 

during 2–24 hours post-release suggest that most 

juveniles buried relatively quickly and did not show 

stress behaviour by ‘balling’ up. Many juveniles 

commenced feeding within hours, as evidenced by 

faeces trails. 

Survival after 6 months was around 28% overall 

(23% for small and 33% for large sandfish). The 

highest overall survival—41%—was recorded from 

a pen of large sandfish (Figure 10), and the lowest 

survival was also from a pen of large sandfish at 23%. 

Losses (due to mortality or escape) were greatest in 

the first 3 months, and thereafter remained relatively 

steady (Figure 10). Due to bad weather causing damage 

to the pens in November 2009, survival is only 

reported up to this time. 

137 

Growth of hatchery-produced sandfish in pens 

was measured every 1–2 months throughout the 

trial (Figure 11). Measurements from the trial are 

considered reliable up until 8 months after release, 

immediately prior to cyclone Tomas in March 2010. 

At this time, average sandfish size was 165 ± 5 g 

and 167 ± 6 g for small and large sandfish, respectively. 

Additional measurements were taken after 

the cyclone (Figure 11), but may also have included 

some wild sandfish because of the damage to pens. 

Processed skin samples did not show any fluorescent 

spicules, as we had suspected during the marking process. 

Therefore, in our case, fluorochrome marking 

was not useful in distinguishing hatchery-produced 

juveniles from wild individuals. A data logger indicated 

that sea temperatures were lower than normal 

in October–November 2010 and early January 2011, 

which may have contributed to the slower growth 

observed during those periods. However, cyclones 

also occurred around those times. 

Community engagement and resource 

management 

Prior to the start of the study (mid 2008), the Natuvu 

chief banned the harvest of sandfish throughout the 

entire qoliqoli. During 2009, an MPA of almost half 

the qoliqoli area was declared, and this initiative was 

supported and ratified by Fiji Fisheries (Figure 12). 

The Natuvu community was closely involved with the

Table 2. Broodstock collection time, hatchery where they were used, collection location, number collected and 

mean (± SE) weight (g) 

Time Location Hatchery Number Mean weight ± SE (g) 

November 2008 Natuvu (2 collections) 

Nawi Island (Savusavu) 

Yaroi (Savusavu) 

Savusavu 70 / 30 

5 

10 

138 

301 ± 8 / 321 ± 8 

857 ± 46 

192 ± 8 

December 2009 Natuvu Savusavu 33 342 ± 15 

March 2010 Natuvu Savusavu 40 453 ± 14 

November 2010 Natuvu Galoa 55 395 ± 17 

Number sandfish observed 

160 

140 

120 

100 

80 

60 

40 

20 

0 

May 09 Aug 09 Oct 09 Nov 09 

Figure 10. Survival of released sandfish in the four pens after 6 months. Solid lines represent pens 

stocked with large juveniles (>3–10 g), and broken lines represent pens stocked with 

small juveniles (1–3 g). 

Mean (± SE) sandfish weight (g) 

200 

160 

120 

80 

40 

0 

Large (A/C) 

Small (B/D) 

19/05/2009 

2/06/2009 

16/06/2009 

30/06/2009 

14/07/2009 

28/07/2009 

11/08/2009 

25/08/2009 

8/09/2009 

22/09/2009 

6/10/2009 

20/10/2009 

3/11/2009 

17/11/2009 

1/12/2009 

15/12/2009 

29/12/2009 

12/01/2010 

26/01/2010 

9/02/2010 

23/02/2010 

9/03/2010 

23/03/2010 

6/04/2010 

Figure 11. Growth data over 11 months for hatchery-produced sandfish at Natuvu. Solid lines 

represent large juveniles (both pens combined) and broken lines represent pens of small 

juveniles (both pens combined). March and April 2010 are subsamples of the sandfish 

located in pens after cyclone Tomas, and data are to be treated with caution. Cyclones are 

denoted by C, and observed spawning in pens is denoted by SP. 

SP 

C 

SP 

C

Figure 12. Marine protected area (broken line) within the Natuvu village 

qoliqoli (solid line). Sea pens are red circles inside the qoliqoli. 

research at all stages of the study. They assisted with 

all project work, such as building pens and releasing 

the juveniles. Four ‘wardens’ were assigned to ensure 

that the hatchery-produced juveniles were protected 

and not disturbed. They also performed routine maintenance 

on the pens, assisted with monitoring and 

carried out other project-related duties. 

Observations by the wardens and other project staff 

suggested that wild sandfish populations improved 

(e.g. increased in size and abundance) following the 

introduction of the protective measures This could 

benefit the seagrass habitat, as sea cucumbers are 

known to have a beneficial ecological effect on the 

substratum through their feeding and burying habits. 

In addition, spawning of hatchery-produced sandfish 

in pens was observed in November 2009 and March 

2010, suggesting that the sea-ranched sandfish may 

contribute to future stock biomass. 

Natuvu locals also stated that other commercial sea 

cucumber species, such as curryfish (Stichopus hermanni, 

a medium-value species), increased in number 

and size within the MPA (Figure 13a). In fact, 

large-size curryfish were observed to be so abundant 

that the community temporarily opened the MPA 

to harvest this species in late 2010. The 300 kg of 

beche-de-mer they processed (Figure 13b) earned the 

community approximately FJ$24,000 (A$15,000)— 

enough to fund a community hall (disaster evacuation 

centre), contribute to church fundraising, support the 

local school and meet other community needs. The 

139 

MPA was closed to fishing again after the curryfish 

harvest. Despite the lack of a large-scale sandfish 

release in their qoliqoli, the community continues to 

protect sandfish throughout the entire qoliqoli and 

is keen to see ongoing research in this area. They 

intend to manage their MPA in collaboration with Fiji 

Fisheries in ways to ensure continued benefits from 

sandfish and other commercial holothurians. 

Discussion 

A number of positive outcomes resulted from the 

ACIAR projects. Private-sector and government 

staff were trained in sea cucumber production techniques, 

leaving a core of skilled and experienced 

technicians in Fiji. Furthermore, national government 

fisheries officers, students and community members 

were trained in release and monitoring methods for 

hatchery-reared juvenile sandfish. During production 

activities, the relative ease of producing sea cucumber 

in non-sea-cucumber hatcheries was demonstrated. 

This suggests that a multispecies hatchery approach 

to aquaculture production may be a successful and 

sensible option for small Pacific island nations where 

there are often shortfalls in resources and trained 

staff. Some variations were made to accommodate the 

local conditions and the available hatchery facilities: 

however, thousands of juveniles were produced with 

comparatively little modification. The lack of pond 

or raceway facilities was a constraint in Savusavu,

while the availability of earthen ponds at Galoa was 

an advantage—production at the latter site may have 

been increased substantially if time and resources had 

permitted. Equipment breakdown and insufficient staff 

were major constraints at Galoa. The failure to produce 

juveniles in subsequent production runs was due to a 

combination of factors, including unfavourable environmental 

conditions, the effects of two cyclones and 

human error. It is noteworthy that the December 2009 

hatchery run was carried out successfully by the Fijian 

hatchery counterparts with no outside assistance, but 

was cut short by a cyclone. Disruptions from cyclones 

were as minor as a few days of bad water quality and 

power loss during larval production, and as severe as 

months of hatchery down time to repair facilities and 

destroyed sea pens, and loss of released animals. 

Production methods were adapted during the projects. 

Changes were based on new techniques from 

Vietnam and the Philippines (e.g. Duy 2010; Gamboa 

et al. 2012) as well as variations customised for Fiji. 

For example, perspex settlement plates were painted 

with a Spirulina paste instead of conditioning with 

Nitzschia sp. (Duy 2010). Another major change was 

applied in the feeding techniques used at Galoa in 

November 2010. The successful rearing of larval and 

early juvenile sandfish by feeding predominantly with 

instant algae was a major breakthrough in terms of simplifying 

techniques for small hatcheries in the Pacific 

region (and potentially other developing countries) 

(Hair et al. 2011b). More research is needed, but the 

use of an off-the-shelf algal diet may prove a huge boost 

for small hatcheries with limited resources and staff. 

Figure 13. (left) Commercial-size curryfish (Stichopus hermanni) and 

(right) Natuvu women with beche-de-mer 

140 

In terms of the success of the trial sea ranching, only 

one small trial was carried out, due to the difficulty 

in getting sufficient numbers of juveniles through to 

release size. However, of those that were released, the 

survival and growth results were encouraging. Both 

large and small sandfish from the release at Natuvu 

grew and survived well. The results compared favourably 

with similar studies in the Pacific islands region 

(Purcell and Simutoga 2008). As reported from the 

Philippines (Olavides et al. 2011), sandfish in pens 

were observed to spawn on two occasions (at 6 and 

11 months post-release). There was a high level of 

community cooperation and commitment in the project, 

with community leaders taking the opportunity to 

apply other management measures around the project 

that led to environmental and financial benefits. 

Technical challenges for Fiji (and many similar 

small nations) continue to include producing live 

feed for larval production, collection and maintenance 

of broodstock, producing sufficient numbers 

of large-sized juveniles, and risk management of 

extreme weather events (in particular, cyclones). 

Management, environmental and socioeconomic 

challenges will undoubtedly become more important 

as the technical issues are overcome. A number 

of sandfish sea-ranching and farming programs in 

more advanced stages may offer solutions or outline 

promising approaches to these challenges (e.g. 

Robinson and Pascal 2009, 2012; Fleming 2012; 

Juinio-Meñez et al. 2012). However, the hatchery 

and release activities described here have increased 

awareness of and interest in the technology. Fiji in

now a position to pursue further development of sea 

cucumber sea ranching if desired. 


The author would like to acknowledge the support 

and assistance from our stakeholders and partners 

throughout this study; in particular, J. Hunter Pearls 

staff, officers of the Fiji Fisheries Department 

(Savusavu, Labasa, Suva and Galoa), the Natuvu 

community, Fiji Locally Managed Marine Area 

network, Caukadrove Yabula Management Support 

Team and University of the South Pacific. 

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and Masuda R. 2008. A new era for restocking, stock 

enhancement and sea ranching of coastal fisheries 

resources. Reviews in Fisheries Science 16, 1–9. 


scabra) in Vietnam. SEAFDEC Aquaculture Extension 

Manual No. 48. 

Fleming A. 2012. Sea ranching of sandfish in an 

Indigenous community within a well-regulated fishery 

(Northern Territory, Australia). In ‘Asia–Pacific tropical 





Gamboa R.U., Aurelio R.A., Ganad D.A., Concepcion L.B. 

and Abreo N.A.S. 2012. Small-scale hatcheries and 

simple technologies for sandfish (Holothuria scabra) 

production. In ‘Asia–Pacific tropical sea cucumber 

aquaculture’, ed. by C.A. Hair, T.D. Pickering and D.J. 

Mills. ACIAR Proceedings No. 136, 63–74. Australian 

Centre for International Agricultural Research: Canberra. 

[These proceedings] 

Hair C., Kaure T., Southgate P. and Pickering T. 2011b. 

Potential breakthrough in hatchery culture of sandfish 

(Holothuria scabra) by using algal concentrate as food. 

SPC Beche-de-mer Information Bulletin 31, 60–61. 

Hair C., Pickering T., Meo S., Vereivalu T., Hunter J., and 

Cavakiqali L. 2011a. Sandfish culture in Fiji Islands. SPC 



Catbagan T., Edullantes C.M. et al. 2012. Establishment 

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and management of communal sandfish (Holothuria 

scabra) sea ranching in the Philippines. In ‘Asia–Pacific 




Agricultural Research: Canberra. [These proceedings]. 

Olavides R.D., Rodriguez B.D. and Juinio-Meñez M.A. 




23–24. 

Purcell S. W. 2004. Criteria for release strategies and evaluating 


sea cucumber aquaculture and management’ ed. by A. 








Purcell S.W., Blockmans B.F. and Agudo N.N.S. 2006a. 



238–244. 

Purcell S.W., Blockmans B.F. and Nash W.J. 2006b. 

Efficacy of chemical markers and physical tags for 

large-scale release of an exploited holothurian. Journal 

of Experimental Marine Biology and Ecology 334, 

283–293. 

Purcell S. and Eeckhaut I. 2005. An external check for 

disease and health of hatchery-produced sea cucumbers. 





Science 16, 204–214. 

Raison C.M. 2008. Advances in sea cucumber aquaculture 

and prospects for commercial culture of Holothuria 

scabra. CAB Review: Perspectives in Agriculture, 

Veterinary Science, Nutrition and Natural Resources 3, 

1–15. 

Robinson G. and Pascal B. 2009. From hatchery to community—Madagascar’s 

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Robinson G. and Pascal B. 2012. Sea cucumber farming 

experiences in south-western Madagascar. In ‘Asia– 







Background Paper 4, Sixth SPC Heads of Fisheries 

Meeting, February 2009. SPC: Noumea.

Sea cucumber farming experiences in 

south-western Madagascar 

Georgina Robinson 1* and Benjamin Pascal 2 

Abstract 

In south-western Madagascar, anthropogenic and environmental factors are adversely affecting 

marine resources, and alternatives to fishing for the local Vezo community are limited. In an effort to 

overcome this problem, a non-government organisation (NGO), Blue Ventures, has been pioneering farming 

of sandfish (Holothuria scabra) in pens as a livelihood strategy for communities. Successful preliminary trials 

resulted in Blue Ventures and the NGO Trans’Mad-Développement obtaining funding to expand the project 

to include 40 families in seven villages. The pens, measuring between 625 and 900 m 2, were constructed in 

nearshore seagrass beds and stocked with batches of 300–450 hatchery-reared juveniles (15 g) at 3–4-month 

intervals. Sea cucumbers reaching a minimum size of 300 g between 4 and 12 months later were harvested 

and sold to the commercial partner, Madagascar Holothurie S.A., for processing and export. During the 

period of the study, a total of 51,500 juveniles were released at seven sites during 21 release events spread 

over 45 months. Although preliminary trials yielded high survival rates (80%), on scaling up the project a 

number of factors led to increased mortality rates; these included suboptimal transportation and stocking 

conditions, and predation. To meet these problems, methodologies were improved and a number of strategies 

were adopted to improve survival of juveniles following release. Socioeconomic issues remained a challenge 

throughout the project, as theft of market-size sea cucumbers was prevalent. 

Introduction 

In south-western Madagascar, anthropogenic and 

environmental factors, including climate change, 

population growth and overfishing, are adversely 

affecting marine resources. Coupled with the aridity 

of the region, alternatives to fishing for the Vezo 

community who inhabit the region are limited. As 

a means to address these issues, a sea cucumber 

mariculture project was launched in Madagascar 

in 1999 (Jangoux et al. 2001). In March 2008 the 

project evolved from its experimental roots into the 

commercial domain with the creation of Madagascar 

Holothurie Société Anonyme (MH.SA), the first private 

company based on sea cucumber aquaculture 

1 Department of Ichthyology and Fisheries Science, Rhodes 

University, Grahamstown, South Africa 


2 Trans’Mad-Développement, Toliara, Madagascar 

142 

in Madagascar (Eeckhaut et al. 2008; Robinson and 

Pascal 2009). 

Since January 2007, the local non-government 

organisation (NGO) Blue Ventures has been pioneering 

sea cucumber farming as a livelihood strategy 

for communities. After preliminary trials demonstrated 

the feasibility of rearing juvenile sandfish 

(Holothuria scabra) in sea pens, funding was obtained 

from the Regional Coastal Management Programme 

of the Indian Ocean Countries (ReCoMaP) for Blue 

Ventures and the NGO Trans’Mad-Développement 

(TMD) to develop community-based holothurian 

mariculture in partnership with commercial operator 

MH.SA. Between September 2008 and September 

2010, the project was scaled up to include 40 families 

in seven villages in south-western Madagascar. 

A handbook on sea cucumber farming has been 

developed that contains detailed methodologies 

used in the project ().

This paper describes community efforts to 

farm hatchery-reared juvenile sandfish in sea 

pens. It examines a series of 21 releases at seven 

sites between January 2007 and September 2010. 

Importantly, it discusses a range of technical, biological 

and ecological factors that affected the survival 

and growth of the farmed sandfish, and outlines adaptations 

to farming practices that were implemented in 

order to address these factors. 

Study sites 

Methods 

The two NGOs operated in geographically distinct 

areas to ensure maximum spatial coverage for the 

project (Figure 1). Extensive site surveys were conducted 

to identify villages with suitable habitat for 

sandfish, comprising shallow, sheltered areas with 

high levels of nutrients, such as muddy substrata 

and seagrass beds (Hamel et al. 2001; Agudo 2006). 

Additional selection criteria included adequate 

sediment depth (~50 cm) for pen construction and 

proximity to the village to facilitate maintenance 

and surveillance of the pens. Seven villages in total 

were selected: Blue Ventures continued to work in 

Andavadoaka, where preliminary trials were conducted 

and expanded to the villages of Nosy Be, 

Ambolimoke and Tampolove, situated within the 

Velondriake Locally Managed Marine Area. TMD 

worked in the villages of Fiherenamasay, Andrevo- 

Bas and Sarodrano, close to the regional capital of 

Toliara (Robinson and Pascal 2009). 

Farming methods 

Initially, pens were constructed from locally available 

materials, using wooden stakes and 10–15 mm 

nylon fishing net. The base of the pens was buried 

25 cm into the sediment to prevent escape of the 

sandfish. Blue Ventures experimented with a variety 

of pen models and sizes ranging from 60 to 

625 m2. After preliminary trials were completed, 

pens were designed in order to maximise growth 

rates, by ensuring that the total biomass in the pens 

did not exceed the natural carrying capacity of 

habitats for Holothuria scabra, believed to be in the 

range 225–250 g/m2 (Battaglene 1999; Purcell and 

Simutoga 2008). The pens measured 25 × 25 m, with 

one-quarter of the pen (12.5 × 12.5 m) sectioned off 

to form a 156.25-m2 juvenile pen and the remaining 

468.75-m2 as a grow-out pen. The production model 

143 

was designed to stock batches of 300 juveniles 

every 3–4 months, with subsequent transfer to the 

grow-out section 5 months after input. However, 

problems were experienced after constructing the 

grow-out section, as the mesh size used (15-mm 

nylon fishing net) led to fish (Lutjanidae, Gerreidae 

and Plotosidae) becoming trapped in the nets. This, 

in turn, attracted crabs, mainly Thalamita crenata, 

which ripped holes in the net, through which sea 

cucumbers could escape (Robinson 2011). The 

pens were eventually reconstructed with 6 × 8 mm 

HDPE plastic mesh; however, the delay in importing 

materials meant that juveniles delivered between 

19 August 2009 and 12 May 2010 were overstocked 

in the 156-m 2 juvenile section, and it was not possible 

to fully test the production model. 

TMD constructed large, open 30 × 30 m pens 

from the outset, which were stocked with batches 

of 450 juveniles every 3–4 months depending on 

availability from MH.SA. In an effort to reduce 

losses from predation in Sarodrano and Andrevo- 

Bas, 25-m 2 protective enclosures were constructed 

in the centre of the pens. The nursery pens had a 

10 mm top net stitched on to prevent the entrance of 

crabs (Figure 2). Juveniles were held in the protective 

enclosures for 2–3 months until they reached an average 

size of 50 g, at which stage they are better able 

to withstand predatory attacks from crabs (Lavitra 

2008) and are well acclimatised to the wild. 

Juvenile supply 

The commercial operator, MH.SA, was responsible 

for the supply and transport of large juveniles 

(approximately 15 g or 6 cm) from the nursery site at 

Belaza, located approximately 20 km south of Toliara 

(Figure 1), to the village grow-out sites. MH.SA was 

given exclusive rights to buy back all market-sized 

sea cucumbers for processing and export. At the start 

of the project, production costs were relatively high 

at US$0.54 per juvenile; thus, project funding was 

used to subsidise the cost for farmers. Juveniles were 

supplied to farmers on credit at a cost of US$0.20 

per juvenile, advanced by project funds, and the cost 

of juveniles was reimbursed at set rates when the 

sea cucumbers were harvested and sold. NGO staff 

were required to relay the number and weights of 

market-ready sea cucumbers to MH.SA 2 weeks prior 

to harvest and sale. In addition, MH.SA imposed a 

minimum size limit of 300 g and a minimum quantity 

of 300 market-sized animals before they would travel 

to the villages for the sale.

Transportation and stocking 

Toliara 

Figure 1. Sandfish farming sites of Blue Ventures and Trans’Mad- 

Développement in south-western Madagascar 

Initially, MH.SA used their fishing vessel to 

transport juveniles from the nursery in Belaza to 

grow-out sites. A number of protocols were put into 

place to minimise handling and maintain optimal 

water quality, such as defecation of juveniles prior to 

transport and regular partial water changes. Juveniles 

were loaded into fish transport boxes (100 per box), 

which were stacked in insulated plastic fish harvest 

bins filled with sea water (Figure 3). Transportation 

occurred overnight or in the early morning in order to 

144 

avoid daytime temperature extremes, and to schedule 

arrival time for juveniles to be stocked during midmorning 

spring low-ebb tides. Transportation times 

to Andrevo-Bas and Fiherenamasay ranged from 4 to 

10 hours (Tsiresy et al. 2011), and journey times to 

reach grow-out sites in Velondriake (200–250 km to 

the north), ranged from 14 to 22 hours depending on 

weather conditions. 

In an effort to reduce the level of mortality due 

to boat transportation, more conventional transportation 

strategies were adopted later in the project 

(Purcell et al. 2006). Juveniles were stocked in 5-L

plastic bags with 2.5 L of sea water and oxygen, 

packed into insulated containers and transported 

directly to the grow-out sites by four-wheel drive 

vehicle. Motorised boats were used to relay juveniles 

to villages with no road access. Where delivery was 

problematic and delayed, contingency plans were 

implemented. On two occasions, juveniles were 

released by SCUBA divers at high tide during the 

day into pens at a water depth of 2.5 m. However, 

as methodologies used in the development of sea 

cucumber farming aimed to maximise community 

participation, it was preferable to keep juveniles 

ashore in open containers, and carry out partial 

water changes until they could be stocked at night 

during the spring low tide. This allowed the juveniles 

a 6–8-hour period to recover from the stress of 

transportation and resume normal behaviour. Prior to 

release, farmers were trained to gradually acclimatise 

juveniles to ambient water temperatures for 30 minutes 

before releasing them individually into the pens. 

Capacity building and monitoring 

The NGOs were responsible for providing training 

and technical support to farmers throughout the 

project, including training in pen construction and 

145 

maintenance, husbandry, conflict resolution and 

financial management. Log books were issued to each 

farming group to record details of all husbandry and 

maintenance activities, together with accounts detailing 

the number of sea cucumbers delivered and sold, 

the amount of juvenile credit repaid and the profits 

generated per group. Participatory monitoring was 

carried out on a monthly basis at night during spring 

low tides to provide data on growth and mortality. 

All sea cucumbers found during monitoring were 

counted, and a minimum subsample of 25% was 

weighed using a top-pan electronic balance. 

Predator control 

Due to high levels of predation experienced at 

some sites, TMD developed a number of targeted 

predator control techniques. Two types of traps were 

designed—a bucket buried in the sand with bait 

suspended across the entrance, and a baited mesh 

cage with a circular opening (Figure 4). Traps using 

locally harvested arc shell meat (Anadara natalensis) 

as bait were deployed around the pens. Farmers were 

encouraged to regularly hunt for crabs in and around 

the pens, with an intensification occurring in the 

month leading up to juvenile deliveries. A variety 

Figure 2. Protective nursery enclosures (25 m 2) constructed in the centre of 30 × 30 m sea pens in 

Sarodrano to protect newly released juveniles from predation

Figure 3. Methods used to transport hatchery-reared juveniles by fishing boat to grow-out sites in 

Velondriake using fish boxes stacked inside insulated harvest bins 

146 

Figure 4. Traps designed by Trans’Mad- 

Développement to capture 

predatory crabs

of techniques were used—using a spear or gloves to 

catch crabs, snorkelling along the sides of the pens to 

flush crabs towards the traps, or trapping and killing 

them. All species were targeted; edible crabs such 

as Lupa sanguinolenta, Scylla serrata, and Lupa 

pelagica were sold or used for domestic consumption, 

and non-edible species (e.g. Thalamita crenata) 

were dried to provide food for pigs and chickens 

(Ravoto 2010). 

Anti-poaching measures 

As theft was considered to be one of the main 

risks facing the project (Robinson and Pascal 2009), 

a number of proactive measures were put in place, 

including nightly surveillance programs and the 

creation of marine reserves governed by social conventions 

(dinas) to regulate access to the mariculture 

zones, and enable villagers to deal with incidents of 

theft at a local level. As theft was prevalent throughout 

the project, a regional meeting, organised by 

MH.SA and chaired by the Minister of Fisheries, 

was held in April 2010 in Toliara. The meeting was 

attended by a wide range of stakeholders, including 

sea cucumber farmers, NGOs, Department of 

Fisheries, police, army, middlemen and seafood traders. 

A number of additional strategies were agreed 

upon, including establishing a system of traceability 

for farmed sea cucumbers by issuing certificates of 

origin; legalising the village dinas at the district level; 

increasing the presence of government officials, 

including fisheries surveillance and police; and 

constructing guard platforms adjacent to sea pens to 

facilitate surveillance. 

Farming trials 

Results 

During the period of the study, 51,500 juveniles 

were released at seven sites during 21 release events 

spread over 45 months (Table 1). 

Survival of hatchery-reared sandfish 

A number of factors were found to affect the 

survival of hatchery-reared sandfish post release, 

including transport and handling stress, predation and 

human factors (poaching), leading to variable survival 

rates between farming sites (Table 2; Figures 5b, 6b). 

During preliminary farming trials, where juveniles 

were properly transported and acclimatised, survival 

rates were high after 11 months, with 79% and 80%, 

147 

respectively, for the first two releases in Andavadoaka 

and Ambolimoke (Table 2). However, the use of the 

boat to transport larger quantities of juveniles from 

October 2008 increased mortality rates. During 

transportation by boat of the first five batches of 

juveniles to grow-out sites in Velondriake, a total of 

3,061 juveniles (11% of the total number of sandfish 

delivered) died (Robinson 2011). The journey by sea 

was frequently complicated and prolonged during 

periods of rough weather, leading to evisceration of 

juveniles and mortalities on board. In December 2009 

the occurrence of a tropical storm in the afternoon 

caused the direct mortality of 55% of juveniles destined 

for Nosy Be (Table 2). During the same month, 

the delivery boat was stuck in heavy seas behind 

the barrier reef in Fiherenamasay, resulting in direct 

mortality of 91% of juveniles. Frequently delayed 

or prolonged transportation also led to suboptimal 

stocking conditions early on in the project. During the 

delivery of 1,200 juveniles to Ambolimoke in October 

2008, the late arrival of the boat resulted in releasing 

the juveniles into pens on a rising spring tide. The 

animals, which were already stressed after a 16-hour 

boat journey with no water exchange, were unable to 

bury or even maintain their position on the sediment, 

and were observed rolling around on the sediment 

surface. Some farmers even reported observations of 

juveniles floating out of the pens as the strong tidal 

current, wind and waves swept through the shallow 

area where the pens were located. Survival rates were 

35% after 2 months (Table 2; Figure 5b). 

During the first releases in Sarodrano and Andrevo- 

Bas, there was intense predation from crabs, with 

mortality rates of 80% and 81%, respectively, after 

2 months (Table 2; Figure 7). Transportation and 

acclimatisation of juveniles for Sarodrano was optimal, 

as juveniles were transported by canoe from the 

nursery (30 minutes) and released at midnight during 

the spring low tide. However, within 20 minutes, large 

numbers of Thalamita crenata arrived at the pens, 

where they succeeded in scaling the pens and ripping 

holes in the sides (10-mm nylon net) to prey on the 

newly released juveniles. One month after release, 

survival estimates between pens varied greatly, ranging 

from 0% to 71%, with an average survival rate of 

20% for the five pens (Table 2; Figure 6b). In an effort 

to protect newly released juveniles from predation by 

crabs, nursery enclosures (Figure 2) were constructed 

after the first release at Sarodrano and Andrevo-Bas. 

With this new system, the observed survival rates were 

79% and 70%, respectively, 15 days after release.

Table 1. Summary of all juvenile sandfish releases, January 2007 – September 2010 

Other factors of importance 

Pen size (m2) No. pens Total 

no. of 

juveniles 

Date Site NGO No. juveniles 

released 

24 January 2007 ADV BV 200 60 1 200 

16 January 2008 ADV BV 200 100 200 

1 October 2008 ABM/ADV BV 1,200/200 *156/100 4/1 1400 *Only juvenile section of pen constructed 

24 February 2009 ABM/ADV/ BV 1,800/450/ *156/225/ 6/1/4/6 5,250 *Only juvenile section of pen constructed 

NSB/ TMP 

1,200/1,800 156 /156 

31 March 2009 SAR TMD 2,250 900 5 2,250 

13 May 2009 FHM TMD 2,250 900 5 2,250 

11 June 2009 ADR TMD 3,150 900 7 3,150 

19 August 2009 NSB/ TMP BV 1,200/2,400 *625/625 4/9 3,600 *Grow-out section constructed with 15-mm nylon 

net 

18 September 2009 SAR TMD 2,250 900 5 2,250 Juveniles released into 25-m2 protective enclosures 

6 October 2009 ABM/ TMP BV 2,700/300 *156/156 9/1 3,000 *Grow-out section removed due to damage to nets 

20 October 2009 ADR TMD 3,150 900 7 3,150 Juveniles released into 25-m2 protective enclosures 

2 December 2009 ABM/ NSB/ BV 2,700/1,200/2,700 156/156/ 9/9 6,600 Juveniles released into 25-m 

TMP 

156 

2 protective enclosures 

17 December 2009 FHM TMD 2,250 900 5 2,250 

3 March 2010 ADR TMD 3,150 900 7 3,150 Juveniles released into 25-m2 protective enclosures 

16 April 2010 SAR TMD 1,800 900 4 1,800 Juveniles released into 25-m2 protective enclosures 

27 April 2010 TMP BV 2,700 156 9 2,700 

12 May 2010 ABM/ NSB/ BV 1,500/1,200 *625/625 5/4 2,700 *Grow-out section reconstructed with HDPE mesh 

27 May 2010 FHM TMD *900 900 2 900 *Quantity reduced due to poor farming efforts 

15 June 2010 ADR TMD *1,500 900 6 1,500 *Quantity reduced due to poor farming efforts 

25 August 2010 SAR TMD *1,200 900 4 1,200 *Quantity reduced due to lack of supply from 

MHSA 

22 September 2010 TMP BV *2,000 625 9 2,000 *Quantity reduced due to lack of supply from 

MHSA 

148 

Site codes: ADV = Andavadoaka; AMB = Ambolimoke; NSB = Nosy Be; TMP = Tampolove; SAR = Sarodrano; FHM = Fiherenamasay and ADR = Andrevo-Bas 

NGOs: BV = Blue Ventures; TMD = Trans’Mad-Développement

SST (°C) 

Mean survival (%) 

Biomass (g/m 3 ) 

32 

30 

28 

26 

24 

0 50100 150 200 250 

Days after release 

100 

80 

60 

40 

20 

250 

200 

150 

(a) 

(b) 

0 

0 

0 50 100 150 200 250 


(c) 

Survival rate 

Mean body weight 

Biomass 

Growth rate 

100 

0.8 

0.6 

50 

0.4 

0.2 

0 

0 

0 50 100 150 200 250 


Figure 5. Biological responses of sandfish in the second release in Ambolimoke on 1 October 2008 into 

four 12.5 ×12.5 m sea pens: (a) sea surface temperature (SST); (b) mean survival and weight 

of released sandfish; (c) biomass and growth rates of released sandfish. NB: There was high 

mortaility within 1 month due to poor transport conditions. 

149 

400 

350 

300 

250 

200 

150 

100 

50 

2.0 

1.8 

1.6 

1.4 

1.2 

1.0 

Mean weight (g) 

Growth rate (g/day)

Unfortunately, however, these positive results led 

farmers to neglect crab culling, both in nurseries 

and the rest of the pens, and survival rates decreased 

dramatically (Tsiresy et al. 2011) (Table 2; Figure 7). 

The effect of protective nursery enclosures on the survival 

rate of newly released juveniles in Andrevo-Bas 

and Sarodrano is shown in Table 2 and Figure 7. In 

Sarodrano, the vigilance of farmers in excluding crabs 

from nursery enclosures prior to and after stocking led 

to survival rates of 88% (76 days after the third input) 

and 83% (60 days after the fourth input) (Figure 7). 

Theft of market-size sea cucumber was also an 

important factor affecting survival. Over the course 

Mean body weight (g) 


450 

400 

350 

300 

250 

200 

150 

100 

50 

100 

80 

60 

40 

20 

150 

of the study period, eight incidents of poaching were 

reported, amounting to 2,735 sandfish, 5% of the 

total number delivered. Seven of the eight reported 

incidents were directly linked to planned harvests 

and sales to MH.SA, either in the 2 weeks prior to 

a sale or following the cancellation of a sale (Table 

2). Furthermore, half of the thefts occurred during 

periods of celebration, including Christmas and New 

Year in 2007 and 2009 (Figure 6b), and Independence 

Day in June 2009. Periods of bad weather, which prevented 

fishers from going to sea, coincided with two 

of these celebration periods, providing an additional 

driver for poaching. 

(a) Sarodrano Fiherenamasay Andrevo-Bas 

0 

0 50100 150 


200 250 300 

(b) Sarodrano Fiherenamasay Andrevo-Bas 

Harvest 

Harvest 

0 

Theft 

0 50 100 150 


200 250 

Harvest 

Figure 6. Biological responses of sandfish at the Trans’Mad-Développement farming sites during 

the first releases of juveniles into five pens in Sarodrano on 1 April 2009 (n = 2,250), 

five pens in Fiherenamsay on 13 May 2009 (n = 2,250) and seven pens in Andrevo-Bas 

on 11 June 2009 (n = 3,150) 

300


100 

90 

80 

70 

60 

50 

40 

30 

20 

10 

0 

t=67 

t=73 

t=76 t=60 

Figure 7. The effect on mean survival of releasing 15-g juveniles into protected nursery enclosures. 

Unshaded bars denote releases into open 30 × 30 m sea pens; shaded bars indicate release of 

sandfish into 25-m 2 covered nursery enclosures. The number of days post-release is indicated 

above each bar. 

Growth of hatchery-reared sandfish 

t=71 

A wide range of growth rates was recorded in 

the farming trials throughout the study period, and 

time to reach commercial size varied between sites 

and individual release events (Table 3). A number 

of factors were found to affect growth, including 

seasonality (water temperature) and stocking density; 

density-dependent factors were linked to site-specific 

carrying capacities. 

The minimum time to reach market size was 

observed in Andrevo-Bas, where 128 animals (16% of 

the stock remaining following mortalities from predation) 

were harvested after only 128 days at an average 

individual weight of 362.4 g. Partial harvests of the 

fastest growing animals (the ‘shooters’) were also carried 

out in Sarodrano, when 206 animals (29%) with 

an average weight of 363.9 g were harvested after 219 

days, and the remaining sea cucumbers (average weight 

410.6 g) were harvested after 290 days (Figure 6b). 

Conversely, some sites showed poor growth rates 

throughout the study period, most notably Andavadoaka 

and Fiherenamasay (Table 3). In Andavadoaka, sandfish 

from trials in January 2007 and January 2008 failed 

to reach commercial size within 12–15 months. 

The carrying capacity for the site was estimated at 

approximately 100 g/m 2. As it would not have been 

151 

t=70 

t=75 

t=70 

t=74 

t=44 

t=61 

Input 1 Input 2 Input 3 Input 4 Input 1 Input 2 Input 3 Input 4 Input 1 Input 2 Input 3 

Sarodrano 

Andrevo-Bas 

Fiherenamasay 

economically viable to rear sandfish at such low densities, 

the site was subsequently abandoned in 2009. In 

Fiherenamasay, poor initial growth rates of 0.23 g/ 

day after 4 months of farming led to experimentation 

by technicians to rework the sediment by either 

‘ploughing’ or removing the top 5-cm layer. These 

two techniques resulted in increasing the weight gain 

of juveniles fivefold and fourfold, respectively, after 

38 days, increasing the average growth rate to 1.0 g/day 

(Tsiresy et al. 2011). Overall, the average growth rate 

for Fiherenamasay was only 0.65 g/day, and the pens 

were relocated to a new site prior to the second release. 

Growth rates were variable within and between 

sites due to effects of stocking density and seasonality, 

indicating that spatio-temporal variation is important. 

During the first field trial in Ambolimoke (January 

2008), 196 juveniles (average weight 14.7 g) were 

stocked in a 100-m 2 pen at densities of 1.96 juveniles/ 

m 2. Survival rates were high (80%); however, the average 

growth rate was only 0.55 g/day. When sandfish 

were harvested experimentally after 11 months, the 

mean weight was only 185.9 g (± 3.0 SE) (Table 3). 

During the second release into new pens in October 

2008, growth rates were higher and sandfish reached a 

market size of 351.8 g (± 3.1 SE) after only 8 months. 

The average growth rate of 1.4 g/day was due to a 

combination of warm water temperature during the

Table 2. Summary table of mortality and losses recorded from selected releases due to varying factors 

Month/year Site Time post 

release 

Table 3. Summary of growth rates and time to harvest recorded for each farming location. NB: Data presented 

is restricted to initial releases where there was no mixing of cohorts. 

Site Release date Average 

growth rate 

(g/day) 

Time to 

harvest 

(days) 

152 

Size at harvest (g) Other comments 

Andavadoaka January 2007 0.5 333—no 

harvest 

150—not achieved Poor site—abandoned 2009 

Ambolimoke January 2008 0.55 340 185.9 Experimental harvest/processing 

Ambolimoke October 2008 1.4 248 351.8 New pens constructed, low 

stocking density due to high 

mortalities 

Nosy Be February 2008 0.82 163 Not achieved Periodic internal theft of large 

sea cucumbers 

Tampolove February 2008 1.19 282 349 (n = 223) Partial harvest, followed by theft 

prior to sale in February 2009 

Sarodrano March 2009 1.6 

1.36 

219 

290 

Fiherenamasay May 2009 0.65 293—no 

harvest 

Andrevo June 2009 1.45 

1.8 

Mortality 

(%) 

128 

220 

Probable cause or mitigating factors 

January 2007 Andavadoaka 11 months 21 Optimal transport (car in bags with oxygen) 

January 2008 Andavadoaka 11 months 20 Optimal transport (car in bags with oxygen) 

January 2008 Ambolimoke 11 months 20 Optimal transport (car in bags with oxygen) 

October 2008 Ambolimoke 2 months 65 Various (long boat journey, no water changes, 

weakened juveniles, rising tide, low pen height) 

March 2009 Sarodrano 67 days 81 Predation (crabs) 

June 2009 Andrevo-Bas 71 days 80 Predation (crabs) 

October 2009 

and March 2010 

Andrevo-Bas 70 and 75 

days 

85 and 79 Protective enclosures, with lax crab hunting 

December 2009 Nosy Be Immediate 55 Physical damage due to boat transport during a 

storm 

December 2009 Fiherenamasay Immediate 91 Physical damage and prolonged transport stress 

due to boat being stuck in rough seas 

February 2010 Tampolove 12 months 99 Theft 2 days prior to a sale to MH.SA (n = 929) 

March 2010 Fiherenamasay 10 months 42 Theft after cancellation of a sale to MH.SA 

(n = 953) 

April and 

August 2010 

Sarodrano 60 and 76 

days 

11 and 17 Protective enclosures, with vigilant crab hunting, 

well-maintained enclosures 

June 2010 Andrevo-Bas 70 days 34 Protective enclosures, with vigilant crab hunting, 

well-maintained enclosures 

363.9 (n = 206) 

410.6 (n = 277) 

Partial harvests, low stocking 

density due to high mortalities 

208—not achieved Poor site—abandoned and new 

site selected 

362.4 (n = 128) 

420 (n = 568) 

Partial harvests, low stocking 

density

summer months and low densities resulting from 

post-release mortality. The growth rate increased 

from 0.88 g/day to a peak rate of 1.69 g/day during 

February and March 2009, when water temperatures 

were ~32 °C. The growth rate then decreased as 

water temperatures fell to 25.6 °C and as the biomass 

approached 220 g/m 2 (Figure 5a, b, c). 

In the farming villages of TMD, for the first 

releases of 450 juveniles per pen, stocking densities 

were low, at 0.5 juveniles/m 2. Medium to high levels 

of mortality were experienced at all three villages 

during the first month (Figures 5, 7b); thus, stocking 

densities were further reduced, and throughout 

the production cycle the biomass never exceeded 

45 g/m 2. At these sites, average daily growth rates 

over the first 5 months for Sarodrano, Andrevo-Bas 

and Fiherenamasay were 1.3, 1.8 and 0.23 g/day, 

respectively (Tsiresy et al. 2011). 

Discussion 

Factors affecting survival 

The following factors have the potential to affect 

the survival of released sandfish: method of transport 

to the release site, size at release, type of substrate, 

time of release (both within the diurnal cycle and 

seasonal), stocking density, abundance of predators 

and availability of food (Battaglene and Bell 2004). 

The impact that some of these factors can have on 

the survival rate of juveniles released into sea pens 

in the wild was highlighted in the results of the study. 

In addition, the effect of techniques developed to 

improve survival during various release events in 

south-western Madagascar was also demonstrated. 

Size at release has a significant effect on survival 

of sandfish (Purcell and Simutoga 2008). In comparison 

with other studies, the high survival rates (~80%) 

obtained when juveniles were properly transported 

and acclimatised was largely due to the large size 

of juveniles released (15 g). During transport and 

release, juvenile sandfish are subjected to a wide 

range of stresses, including physical shocks and 

prolonged agitation, periods out of water, temperature 

shocks, buffeting by tidal currents and wave action, 

and predators (Dance et al. 2003; Purcell 2004). 

Therefore, optimal transportation and acclimatisation 

strategies should be employed to maximise survival 

of hatchery-reared sandfish released into the wild. 

Predators constitute one of the main risks to be 

considered for sea cucumber aquaculture using 

153 

pens (Lavitra et al. 2009). High mortality due to 

predation was a major obstacle to the economic 

viability of some of the aquaculture ventures 

(Tsiresy et al. 2011). Purcell (2010) postulated that 

minimal handling of juveniles in transporting them 

into the wild should promote longer periods of burial 

for the first days after release, which may improve 

post-release survival by enhancing their avoidance 

of predators. However, our results indicate that, 

at some sites that were subject to high predation 

pressure, behavioural modifications post release 

were not sufficient to prevent predation. The results 

of this study demonstrate the positive effect that 

providing a physical barrier to predators can have 

on increasing survival of hatchery-reared sandfish. 

However, a two-pronged approach is needed; the 

combination of using protective nursery enclosures 

in conjunction with targeted predator control proved 

extremely effective in increasing survival rates of 

newly released hatchery-reared sandfish, as demonstrated 

by the success of farmers in Sarodrano who 

remained vigilant in crab hunting and maintaining 

enclosures. 

After a number of biological and technical hurdles 

affecting survival of sandfish were overcome, 

and once market-sized sea cucumbers started to be 

reliably produced in sea pens, a new set of socioeconomic 

problems came into play as theft became 

prevalent. The issue of theft was exacerbated by a 

number of weaknesses in the business model. First, 

the fact that credit was extended to farmers to obtain 

juveniles eliminated any risk on their part, and 

therefore did not engender responsibility among 

farmers. Second, the low prices paid by MH.SA of 

approximately US$1.00–1.39 per piece, from which 

juveniles’ costs were also deducted, often meant that 

it was more profitable for farmers to sell their sea 

cucumbers to traders in the neighbouring villages. 

Finally, the 2-week time delay, enforced by MH.SA, 

between NGO staff communicating the number and 

weights of market-ready sea cucumbers to MH.SA, 

and MH.SA staff travelling to Velondriake to buy 

them, increased the risk of theft in the interim period, 

when the majority of thefts occurred. 

Factors affecting growth 

Density-dependent factors were not found to 

directly affect survival of sandfish, but they were 

important in regulating growth rates. During this 

study, lower stocking densities appeared to lead 

to higher growth rates, and high growth rates were

ecorded in periods of high water temperatures. 

Battaglene (1999) observed that growth of Holothuria 

scabra ceased when densities reached approximately 

225 g/m 2, and that even juveniles held at this density 

lost weight. A study by Purcell and Simutoga (2008) 

on the long-term growth of sandfish in the wild also 

indicated a natural carrying capacity for sandfish of 

around 2.5 t/ha for farming programs. Our results also 

indicated that carrying capacities for sandfish exist and 

affect their growth rate. However, we found there was 

considerable variation between sites. In Ambolimoke, 

growth rates slowed as the biomass reached ~220 g/m 2 

although water temperature was also a contributing 

factor. In Andavadoaka, the low carrying capacity of 

the site (~100 g/m 2) prevented sandfish from reaching 

market size after 12–15 months. In addition, when 

sandfish were released temporarily at this site at biomass 

of 360 g/m 2, the effects of overcrowding were 

evident as sandfish were observed squeezing through 

the mesh in an effort to disperse. 

Density-dependent effects on growth rate are likely 

to be linked to food availability; however, it appears 

that some sites are capable of supporting higher 

stocking densities than others. For example, the sea 

pens opposite the MH.SA nursery in Belaza are 

capable of supporting a biomass of ~700 g/m 2, and it 

is therefore possible for sandfish to reach market size 

at a density of 2 individuals/m 2 (Lavitra 2008). As 

the carrying capacity of the site will strongly affect 

the economic viability of farming sandfish, a simple 

method was developed during the project to assist 

with optimal site selection and to assess the carrying 

capacity of potential sites. Small 4-m 2 test plots 

were stocked with juveniles, and weekly growth was 

monitored until the sea cucumbers stopped growing 

due to density-dependent effects, at which point the 

total biomass per unit area was calculated (Pascal and 

Robinson 2011). 

Highly variable growth rates within specific 

cohorts lead to heterogeneous sizes of sandfish 

(Purcell and Kirby 2006), which was confirmed by 

this study. In some echinoderm species, the presence 

of larger individuals can suppress the growth 

of smaller ones (Grosjean et al. 1996; Dong et al. 

2010); therefore, grading is often used in aquaculture 

to produce uniform size classes. In some cases the 

removal of ‘shooters’ (fast-growing individuals) can 

allow the smaller ones to catch up, as seen in the successful 

partial harvests at villages near Toliara. In-situ 

partial processing of sea cucumbers at the community 

level is now being investigated. In addition to 

154 

alleviating incidents of theft, as sea cucumbers can 

be harvested and processed on a regular basis as they 

reach market size, it may also lead to the production 

of more uniform batches of sandfish, and reduce the 

time to reach harvest size. 

Conclusions 

Over recent years, research has led to the development 

of reliable techniques to produce hatcheryreared 

sandfish (James et al. 1994; Battaglene 1999; 

Agudo 2006; Duy 2010). Studies on the release of 

hatchery-reared juveniles commonly report high 

levels of mortality during the first few months after 

release into the wild (Dance et al. 2006; Purcell 

and Simutoga 2008; Hair et al. 2011), yet the 

probable cause of mortality remains unidentified 

or unreported. It is perhaps timely then for future 

research priorities to focus on improving survival of 

hatchery-reared juveniles in the wild. By gaining a 

better understanding of the factors that affect their 

survival in the natural environment, acclimatisation 

and release strategies can be improved. Enclosures 

or cages acting as an intermediate ‘halfway home’ to 

acclimatise juveniles during the first days or weeks 

of release have been suggested (Dance et al. 2003; 

Purcell 2004). In Vietnam and the Philippines, new 

technologies such as floating and fixed bottom hapa 

nets in ponds and the sea are currently being used 

(Duy 2010; R. Gamboa, pers. comm.) to extend the 

nursery phase into the marine environment, in order 

to increase production capacity and reduce production 

costs. It is likely that such techniques, in addition 

to being more cost-effective, will also produce 

hardier juveniles more capable of withstanding the 

broad range of abiotic and biotic conditions of the 

marine environment. 


The authors particularly wish to thank the 

Trans’Mad-Développement and Blue Ventures aquaculture 

teams for their hard work and commitment to 

the project. Funding was provided by the Regional 

Coastal Management Programme of the Indian 

Ocean Countries (ReCoMaP), which also provided 

significant support and input throughout the 2-year 

project. Sincere thanks to the Australian Centre 

for International and Agricultural Research for the 

opportunity to attend the Asia–Pacific Tropical Sea 

Cucumber Symposium in Noumea in February 2011.

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Research, Secretariat of the Pacific Community and 

WorldFish Center: Noumea, New Caledonia. 

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for stock restoration and enhancement. Naga – The 

ICLARM Quarterly 22, 4–11. 


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ed. by D.M. Bartley and K.M. Leber. FAO Fisheries 



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Dong S.L., Liang M., Gao Q.F., Wang F., Dong Y.W. and 

Tian X.L. 2010. Intra-specific effects of sea cucumber 

(Apostichopus japonicus) with reference to stocking density 

and body size. Aquaculture Research 41, 1170–1178. 



Development Center Aquaculture Extension Manual 

No. 48. 

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M.W., Gildas P. and Jangoux M. 2008. Madagascar 

Holothurie S.A.: the first trade company based on sea 

cucumber aquaculture in Madagascar. SPC Beche-demer 


Grosjean P., Spirlet C. and Jangoux, M. 1996. Experimental 

study of growth in the echinoid Paracentrotus lividus. 

Journal of Experimental Marine Biology and Ecology 

201, 173–184. 

Hamel J-F., Conand C., Pawson D.L. and Mercier A. 2001. 








J.X. 1994. Hatchery techniques and culture of the sea 

cucumber Holothuria scabra. Central Marine Fisheries 

Research Institute Special Publication No. 5. 

Jangoux M., Rasoloforinina R., Vaitilingon D., Ouin J.M., 

Seghers G., Mara E. et al. 2001. A sea cucumber hatchery 

and mariculture project in Tuléar, Madagascar. SPC 


Lavitra T. 2008. Caractérisation, contrôle et optimalisation 

des processus impliqués dans le développement postmétamorphique 

de l’holothurie comestible Holothuria 

scabra [dissertation]. University of Mons-Hainaut: Mons, 

Belgium. 

155 




Bulletin, 29, 20–30. 

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farming. Regional Programme for the Sustainable 

Management of the Coastal Zones of the Countries of 

the Indian Ocean (ReCoMaP). At: 

Purcell S.W. 2004. Criteria for release strategies and 

evaluating the restocking of sea cucumber. In ‘Advances 

in sea cucumber aquaculture and management’, ed. 

by A. Lovatelli, C. Conand, S. Purcell, S. Uthicke, 

J.-F. Hamel and A. Mercier. Fisheries Technical Paper 

No. 463, 181–192. Food and Agriculture Organization 

of the United Nations: Rome. 

Purcell, S.W. 2010. Diel burying by the tropical sea cucumber 

Holothuria scabra: effects of environmental stimuli, 

handling and ontogeny. Marine Biology 157, 663–671. 

Purcell S.W., Blockmans B.F. and Agudo N.S. 2006. 



238–244. 

Purcell S.W. and Kirby D.S. 2006. Restocking the sea 

cucumber Holothuria scabra: sizing no-take zones 

through individual-based movement modelling. Fisheries 





Science, 16, 204–214. 

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contexte d’elevage des holothuries. Memoire license de 

la mer et du littoral. Institute Halieutique et des Sciences 

Marines, University of Tulear. 

Robinson G. 2011. Community-based sea cucumber 

aquaculture in Madagascar. In ‘Mariculture in the WIO 

region: challenges and prospects’, ed. by M.Troell, T. 

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Tsiresy G., Pascal B. and Plotieau T. 2011. An assessment 

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in southwestern Madagascar. SPC Beche-de-mer 

Information Bulletin 31, 17–22.

Sea ranching of sandfish in an Indigenous 

community within a well-regulated fishery 

(Northern Territory, Australia) 

Ann E. Fleming 1* 

Abstract 

The Northern Territory is in a unique position to support sandfish (Holothuria scabra) ranching as it has an intact 

wild fishery and low poaching pressure. Indigenous people own 85% of the coastline, and are keen to develop 

economic opportunities through their natural resources. The commercial wild-caught sector has well-established 

markets, and has expressed a willingness to partner with Indigenous coastal communities. Research currently underway 

is focused on the biological and economic feasibility of sea cucumber ranching as well as developing effective 

facilitation and evaluation approaches to ensure that Indigenous people drive enterprise development themselves. 

Introduction 

A wild sea cucumber fishery operates across northern 

Australia, extending from the tropical regions 

of Western Australia, across the Northern Territory 

(NT), to tropical Queensland in the east. This paper 

reports on the fishery within the NT, which comes 

under the management and regulation of the Northern 

Territory Government (2009). 

Compared with countries also working to develop 

sea cucumber ranching, the NT is in a unique position. 

It has an intact and sustainable wild-catch fishery 

with well-established supply chains and markets. This 

is largely due to a strong management regime and the 

efforts of the commercial sector, which consists of a 

single operator who owns all six available licences. 

In addition, the NT has a large population of coastal 

Indigenous Australians who own 85% of the coastline, 

and who aspire to pursue economic development 

through the use of their natural marine resources. 

The recent recognition of Aboriginal people’s legal 

ownership of the intertidal zone within the NT offers 

1 Aquaculture Branch, Fisheries Group, Department of 

Resources, Darwin, Northern Territory, Australia 


156 

further opportunities for marine-based economic 

activities. The commercial wild-catch operator has 

demonstrated a willingness to partner with Indigenous 

communities to establish sea-ranching enterprises, 

and is currently operating a commercial hatchery in 

the NT, and conducting pond-based grow-out and 

sea-ranching trials, the latter with a community on 

Groote Eylandt (Bowman 2012). 

Another unusual factor that exists within the NT 

is the absence of significant sea cucumber poaching 

activity. This is largely because local people, both 

Indigenous and non-Indigenous, do not eat sea 

cucumbers, and because illegal take by Indonesian 

fishers has been drastically curtailed in recent years 

due to enhanced surveillance and apprehension 

operations. 

The implications of this unique set of factors in 

the NT will be discussed in this paper in the context 

of opportunities for sea cucumber aquaculture by 

Indigenous people living in remote communities. 

The wild fishery context 

A modern wild fishery, targeting the high-value 

sea cucumber, sandfish (Holothuria scabra), has 

operated in the NT since the 1980s. It continues

to be sustainable today due to the precautionary 

management approach by the NT Government and 

a unique set of circumstances around the nature of 

the commercial sector and the characteristics of the 

operating environment. 

The fishery is divided into two zones, three 

licences per zone, with six licenses in total. The 

government’s conservative approach includes a limit 

on the number of licences and the area of the fishery 

(within 3 nautical miles of the coast to preserve 

deeper sea breeding stocks considered important for 

recruitment). Collection of sandfish is by diving from 

vessels, using hand methods only. 

Fishery management aims to ensure intergenerational 

equity of stocks, and it does this by having a 

range of performance indicators, any one of which 

can trigger a management response. The performance 

indicators are: 

• a breach of a total catch of 300 t/year (wet weight) 

• a variation in the rolling 3-year average catch per 

unit effort by a factor of 30% from the current 

year value 

• a decrease in the average weight by more than 20% 

• a change in species composition to over 30% of 

total catch 

• a change in licence ownership. 

The government takes this precautionary management 

approach due to the limited knowledge of the 

biology and ecology of sandfish. Consequently, there is 

a push, initiated by the Australian Government, towards 

addressing key research priorities to fill the knowledge 

gaps and develop meaningful yield estimates. 

The second set of factors that contribute to sustainability 

are around the nature of the commercial sector 

and the characteristics of the operating environment: 

• There is only one licencee, so there is no ‘gold 

rush’ mentality around fully harvesting the good 

stocks. 

• The company has the ability to rotate harvests. 

• Crocodiles, poor visibility, monsoon season and 

extreme tidal range restrict access to many fishing 

grounds, and limit the ability of divers to pick up 

all harvestable stocks. 

• There is relatively low poaching activity (at least 

in recent years). 

In the past, the incidence of illegal fishing in 

northern Australian waters, predominately by 

Indonesian sea cucumber vessels, has been considerable. 

However, recently, there has been a significant 

increase in the apprehension of illegal vessels, from 

60 in 1999 to 210 in 2005. 

157 

In 2006, the Australian Fisheries Management 

Authority (AFMA) set in place an extensive surveillance 

and apprehension program within the Australian 

Fishing Zone using aircraft and sea vessels, together 

with extensive data gathering. As a result of this 

concerted effort, by 2009 the apprehension rate was 

down to nine vessels in the first 5 months (AFMA, 

pers. comm.). Clearly, the message had filtered back 

to illegal fishermen in Indonesia that surveillance had 

increased and apprehension was likely. 

It is interesting to consider this illegal activity by 

Indonesian fishers in the context of the long history 

of sea cucumber (or ‘trepang’ as they are traditionally 

known) fishing in northern Australian waters by the 

Macassans from Sulawesi. They came each year in 

the monsoonal months and fished for trepang, often 

working in collaboration and mutually beneficial 

trade with the coastal Aboriginal people (Macknight 

1976). They had been doing this since around the mid 

1700s until Europeans put a stop to it in 1907 to allow 

local white people to take over the trade. As a result 

of this historical sustained contact with Indonesians, 

Northern Territory Aboriginal people have a cultural 

affiliation with trepang and with the fishing activity, 

even though they do not eat sea cucumber. 

In addition to the unique factors around the wild 

sector, there are also some quite unusual characteristics 

around current sea-ranching aspirations, by 

both Indigenous people and the commercial sector. 

In 2008 the High Court of Australia gave legal 

recognition to Indigenous Australians’ ownership 

of the intertidal zone within the NT (Altman 2008). 

Negotiations are currently underway to determine 

access to marine resources in that zone. Irrespective 

of the final outcome of negotiations, there are 

opportunities for Indigenous people to conduct 

sea ranching and on-sell to the commercial sector, 

which has demonstrated a willingness to partner with 

Indigenous people in this enterprise, committing to 

buy all postharvest or first-process product. 

The sea-ranching trials 

In 2009 the NT Government began working with the 

commercial operator on two trials to assist Indigenous 

communities to establish sea-ranching enterprises. 

One is in partnership with the Warruwi community of 

Goulburn Island and the other with the Umbakumba 

community on Groote Eylandt. The former is an 


Research (ACIAR) project in partnership with a

oader project involving Vietnam and the Philippines 

that is led by the WorldFish Center. 

On Goulburn Island an 18-ha research site has 

been established and four research pens set up to 

monitor growth and survival according to the methods 

developed by Purcell (2004, 2012) and Purcell 

and Simutoga (2008). The site is a perched reef, 

accessible only at low tides when water levels are 

10–30 cm deep. Suitable daytime low tides occur 

only between August and March. The danger of 

crocodile attack precludes diving or snorkelling. 

Surveys have shown that standing stocks of wild 

sandfish are healthy in the trial area. These will be 

removed prior to release of juveniles produced by the 

private sector in collaboration with government staff. 

Releases of approximately 10,000 fluorochromestained 

5-g juveniles are planned using a cage release 

method developed by the private sector. The release 

cages are designed to exclude most predators, and 

protect animals from extreme water currents resulting 

from the 5-m tide difference. Animals are expected 

to move out of the cage as they become acclimatised. 

The logistics of working at the site make the research 

very difficult, primarily due to extreme currents, 

crocodiles, infrequent daytime low tides and the cost 

of flights to these remote areas. Data from the searanching 

trials will be used to assess economic and 

biological viability. Assuming the trials demonstrate 

that sandfish sea ranching is viable, future work is 

likely to see expansion of trials to other sites within 

the West Arnhem region. 

Strategic approach to 

Indigenous engagement 

The NT Government’s Aquaculture Branch seeks to 

identify aquaculture enterprises that meet a set of 

social and economic criteria that increase the likelihood 

of Indigenous enterprise success. The focus is 

on selecting species and farming activities that: 

• have low capital requirement and low, infrequent 

management/operational demands 

• meet social and cultural criteria suitable for 

Indigenous engagement and job participation (e.g. 

culturally relevant species, culturally familiar and 

engaging operational activities, flexible weekly 

working hours, work that enables people to attend 

to cultural activities and obligations for extended 

periods of time) 

• have high market value and strong to medium 

market demand, with existing supply chains and/ 

158 

or clear commercialisation pathways. However, it 

is recognised that a staged approach where people 

develop familiarisation with farming through first 

engaging in more culturally aligned activities and 

outcomes is more likely to achieve success. Thus, 

target species, and the products and uses of those 

products, may be developed for purely social and 

cultural outcomes as a staged approach to longer 

term economic outcomes 

• have a commercial partner and/or project enterprise 

champion and facilitator. 

Sandfish sea ranching meets the criteria for suitable 

Indigenous development projects in terms of 

these social, technical and economic assessments. 

Nevertheless, capacity to engage in western-style 

commerce and participate in the mainstream workforce 

is low for most communities. To overcome 

these barriers, the Aquaculture Branch is partnering 

with social scientists and trained Indigenous research 

practitioners to ensure that people define their vision 

for their community and their work style aspirations 

(in their first language), conduct research to develop 

successful engagement and governance models, 

gauge effectiveness in meeting community aspirations, 

and measure both community and individual 

social and economic outcomes. Such evidence is 

critical to identifying success and failure points, 

thus ensuring that a culture of continual learning is 

embedded in current activities to inform future ones. 

Community-based organisations and agencies play 

an important facilitation role in this ‘bottom-up’, 

community-driven approach, particularly in assisting 

people to develop appropriate governance arrangements 

and capabilities, and providing job-specific 

training. However, enterprise facilitators must ensure 

that they do not influence enterprise development 

choices, but allow the community to decide what 

the outcomes for aquaculture enterprises will be in 

the short term. In this way external non-Indigenous 

people are less likely to unwittingly impose culturally 

inappropriate development choices on people. 

Another important aspect of facilitating community 

enterprise development is to work with the 

children. The Aquaculture Branch has worked with 

the Warruwi school on Goulburn Island to enhance 

awareness of the current trepang trials on their lands, 

as well as the history of trepanging with Macassans 

by their grandparents and distant ancestors on the 

island. The education program also seeks to communicate 

the potential future opportunities and 

benefits of aquaculture enterprises if the trials prove

Warruwi community members inspecting sandfish holding pens on Goulburn Island, Northern 

Territory, Australia (Photo: Wayne Tupper) 

successful. In this way the community’s youth will 

foster aspirations to take advantage of such opportunities 

when they become young adults. Job-specific 

training will be developed for current participants if 

the trials prove successful, enabling them to readily 

progress to paid work when enterprises become 

profitable. 

The above approach requires the Aquaculture 

Branch to form effective working partnerships between 

agencies to facilitate enterprise development. The 

Branch is therefore developing a policy on Indigenous 

aquaculture development that identifies the key guiding 

partnerships, activities and principles to underpin 

Indigenous aquaculture development in communities. 

This policy will guide the activities of the Aquaculture 

Branch and its partners when facilitating aquaculture 

enterprises and activities in communities. 

Summary 

The unique context in the NT—where Indigenous 

communities own most of the coastline (now including 

the intertidal zone), the commercial sector has 

well established markets and is keen to partner with 

Indigenous communities, and there is largely no 

159 

poaching—offers culturally and socially suitable 

natural resource-based opportunities for Indigenous 

people living in remote coastal communities. In relation 

to pursuing sea-ranching enterprise development, 

facilitators must recognise the following: 

• Social disadvantage and cultural differences 

require facilitators to take a whole-of-community 

perspective of physical and human resource 

development. They must commit to a long-term 

course of facilitation, and must install processes 

to ensure that Indigenous people drive the visioning, 

planning and implementation process. Thus, 

partnerships between agencies must be formed to 

bring together the broad range of skills necessary 

to facilitate enterprise development. 

• Selection of species and sea-ranching methods 

must meet social and cultural criteria suitable for 

Indigenous engagement and capacity. 

• The terms of collaboration between the commercial 

sector and Indigenous communities must allow 

for a win–win outcome to work in the long term. 

• Evidence must be gathered to identify success and 

failure points, thus ensuring that a culture of continual 

learning is embedded in current activities to 

inform future ones.

Further, in relation to sea cucumber ranching, 

facilitators must recognise that time frames must be 

appropriate (i.e. long) to ensure gradual development, 

because: 

• technologies are not yet established 

• many logistical factors have to be addressed 

• the capacity to identify suitable sites is not certain 

• economic returns are yet to be determined 

• Indigenous engagement for many communities is 

not yet adequate for effective participation. 

The government is keen to take a cautious 

approach to facilitating development so that expectations 

can be managed. Indigenous people are 

accustomed to waves of failed ventures coming and 

going through their community. The government 

wants to see this enterprise develop in a way that 

maximises the chances of success, both socially and 

economically. Past evidence from successful natural 

resource based enterprises point to a gradual, measured, 

community-controlled approach as the way to 

achieve this. 

References 

Altman J. 2008. Understanding the Blue Mud 

Bay decision. Australian National University. 

At: 

160 

Bowman W. 2012. Sandfish production and development 

of sea ranching in northern Australia. In ‘Asia–Pacific 





Macknight C.C. 1976. The voyage to Marege: Macassan 

trepangers in Northern Australia. Melbourne University 

Press: Carlton, Victoria. 

Northern Territory Government 2009. Trepang fishery 

status report. Pp. 113–119 in ‘Fisheries Status Report 

2009’. Northern Territory Government, Department of 

Resources. 


the restocking of sea cucumber. In ‘Advances in 






Purcell S.W. 2012. Principles and science of stocking 

marine areas with sea cucumbers. In ‘Asia–Pacific 





Purcell S.W. and Simutoga M. 2008 Spatio-temporal and 



Science 16, 204–214.

Resource tenure issues 

Sea cucumber processing by a Fijian exporter (Photo: Cathy Hair) 

161

Marine tenure and the role of marine 

protected areas for sea cucumber 

grow-out in the Pacific region 

Semisi V. Meo 1* 

Abstract 

Many Pacific island countries are reviving longstanding customary marine resource management systems and 

traditional tenure through the locally managed marine area (LMMA) approach. The customary tenure systems 

vary: some are formally recognised in national laws, while for others the recognition is informal. These practices 

include seasonal bans on harvesting, temporarily closed (no-take) areas, and restrictions placed on certain times, 

places, species or classes of persons. The LMMA demonstrates the shared vision of stakeholders that promotes 

the success of adaptive management, as evidenced by healthy ecosystems and communities, abundant marine 

and fish stocks, sustainable fisheries utilisation, protected marine biodiversity, sustainable development in coastal 

communities, an understanding of what communities are doing and can do in managing marine areas, and an 

understanding of ecological and socioeconomic responses to LMMA and coastal management implementation. 

The LMMA approach helps to ensure that benefits from marine conservation efforts will accrue to the local 

community, generally in an equitable manner, benefiting them spiritually, culturally, communally, socially and 

economically. A Fijian site in Verata district revealed that, since 1997, there has been a 20-fold increase in clam 

density in the tabu areas, a 200−300% increase in harvest in adjacent areas, a tripling of fish catches, and a 

35−45% increase in household income. Similar trends have also been observed in the other tabu areas across 

Fiji in a range of potential marine commodities, such as giant clam, seaweed and coral transplanting. Currently, 

there are more than 200 traditionally imposed LMMAs, including tabu areas, and numbers continue to grow. 

In Fiji, application of the LMMA approach at Natuvu village on the island of Vanua Levu has demonstrated 

how a customary tenure system can be integrated with sea ranching of sandfish in a closed area. The entire process 

can be governed by Fijian customary institutions and laws that incorporate local socioeconomic considerations, 

and provide more diverse and culturally appropriate approaches to enforcement, compliance, monitoring and 

restitution. The effectiveness of traditional practices is a reflection of the strength and viability of the customary 

law regime. There may also be issues regarding enforcement, the viability of a closed area in the long term, and the 

roles taken by governments, communities and traditional leaders. Traditional practices are generally accompanied 

by strategies and resources to support sustainable use, viable livelihoods and equitable sharing of benefits. 

Introduction 

Customary tenure in the Pacific region has been well 

documented by Hickey (2006), and a comprehensive 

compilation of the different types of tenure system 

and their implications is set out in case studies for 

1 Institute of Applied Sciences, University of the South 

Pacific, Suva, Fiji 


162 

Pacific island countries by Vierros et al. (2010). In 

summary, the tenure systems are diverse and unique 

to the traditions and cultures across the island 

nations. However, a few of these countries are either 

beginning to lose or are phasing out fundamental elements 

of their traditions in modern times (Vierros et 

al. 2010). Although some of the Pacific island nations 

still hold onto strong traditional tenure, there are variations 

in management influenced by modern practices 

and efficient technology. The locally managed marine

area (LMMA) approach is one that seeks to retain 

and revive traditional approaches in marine tenure, 

and facilitate their use as a means to provide solutions 

for modern-day marine resources management 

issues confronting coastal communities. 

This paper provides an overview of the tenure systems 

across the Pacific region, the associated initiative 

of LMMA and the opportunities it presents, and 

suggestions for how the grow-out process of cultured 

sea cucumber could be carried out successfully. The 

geographical areas under LMMA across the region 

are highlighted. Further, the ability of tabu areas 

to protect sedentary marine organisms sharing the 

same habitats and ecosystem as sea cucumbers is 

discussed, based upon qualitative and anecdotal 

information collected. Tabu areas are portions of 

traditional fishing grounds that have been consensually 

approved by the community owners to be closed 

to fishing or harvesting. The paper also provides an 

account of how the traditional marine tenure system 

in one Fijian community could be mobilised, via the 

LMMA approach, to integrate the management of 

sea ranching of sea cucumbers. 

Customary tenure systems 

Customary marine resource management practices 

have long been used in some Pacific island communities 

in accordance with traditional spiritual 

beliefs. These practices include seasonal bans on 

harvesting, temporarily closed (no-take) areas, and 

restrictions placed on certain times, places, species 

or classes of persons. Closed areas include the tabu 

areas of Fiji, Vanuatu and Kiribati, the ra’ui in the 

Cook Islands, the kapu in Hawaii, the tambu in 

Papua New Guinea, the bul in Palau, the mo in the 

Marshall Islands, the tapu in Tonga and the rahui 

in New Zealand. 

In Palau, the bul can be put in place to close an 

area of reef to harvesting on a short-term basis, such 

as during periods of fish spawning. Vanuatu also 

has networks of spatial–temporal refugia created as 

part of a range of customary practices, such as the 

ordination or death of a traditional leader, the death 

of a clan member, grade-taking rituals, and agricultural 

and ritualised exchange cycles (Hickey 2006). 

Such area closures may be off limits to fishing for as 

long as 7 years. Historically, Hawaiians also used a 

variety of traditional marine resource management 

practices, which included kapu (fishery closures). 

These closures were often imposed to ensure catches 

163 

for special events, or as caches for when resources 

in the regular fishing grounds ran low. 

In Fiji, traditional marine practices still exist, 

even though they have been eroded to some degree 

over the years. For example, when a high chief dies, 

certain marine areas are restricted for approximately 

100 nights. Moratoriums are also put in place for traditional 

ceremonies or funerals; once the restriction 

period has ended, the area is reopened for public use. 

Bans also exist for seasonal harvesting; for example, 

the yellowing of the traditional Fijian beach trumpet 

tree (Cordia subcordata) indicates the octopus mating 

and spawning season, at which time a temporary 

ban on catching octopus is put in place. Recently, 

such practices have been strengthened through the 

codification of traditional ownership of rights to 

harvest fish in coastal areas of Fiji. 

During the past decade, many Pacific island 

countries have experienced a revitalisation of traditional 

management systems and tenure (Johannes 

1998; Govan et al. 2008). In some cases, customary 

tenure systems are recognised in national law, while 

recognition of others is informal. Fiji is one of the 

few countries that have demarcated boundaries, to 

legally recognise a total of 410 fishing-rights areas 

or I qoliqoli—pronounced ‘ng-go-lee, ng-go-lee’— 

which are communally owned fishing grounds passed 

down through generations (Figure 1). These records of 

the ownership of fishing areas are one of the strengths 

of the traditional marine management system in Fiji. 

The demarcation process took approximately 20 years 

(1974–94) and has been applied to the customary 

fishing areas, which are generally inshore (from the 

high-water mark to the reef outer edges). 

Interestingly, in the context of the current debate in 

the United Nations relating to governance of the high 

seas, the traditional fishing grounds in Fiji extended 

as far offshore as one could go, which could be a 

considerable distance in a fishing boat. The presentday 

I qoliqoli can range from 0.5 to more than 10 km 

out to sea from the high-water mark. Beyond the 

I qoliqoli boundaries are Fiji’s archipelagic waters, 

over which the government has legal control. Every 

Indigenous Fijian must be registered to a clan to 

have the right to fish in the I qoliqoli. As a token of 

respect, permission from the chief must be sought to 

fish in another I qoliqoli, even if the individual has an 

ancestral connection to that area. While demarcation 

of boundaries is perceived to be positive, it can also 

create conflict: if an area is overfished, people tend to 

move out to other I qoliqoli (Aalbersberg et al. 2005).

Land 

Fishing boundaries 

Figure 1. Map of the I qoliqoli or traditional fishing areas in Fiji 

Locally managed marine areas 

(LMMA) network 

The LMMA network is a group of marine conservation 

practitioners who have joined together to 

learn more about and increase the success of their 

implementation efforts. The network trains practitioners 

and community members how to collect 

comparable monitoring data from their project sites, 

and assists these groups in sharing and systematically 

learning from one another about LMMA project 

implementation across the region. It is active in eight 

Asia–Pacific countries, including the Philippines, 

Indonesia, Papua New Guinea, Solomon Islands, 

Vanuatu and Fiji. There are more than 400 active conservation 

sites and the level of interest in the network 

is growing. The LMMA network envisions providing 

an enabling environment for its respective membercountry 

networks and its various stakeholders to 

facilitate community-based adaptive management in 

their own countries. 

Fiji’s LMMA (FLMMA) network, consisting 

of over 200 communities, protects about 30% of 

Fiji’s nearshore reefs. The FLMMA network, in 

collaboration with other national stakeholders, is 

working towards establishing community resource 

management action plans in the 410 I qoliqolis 

around the country and, at the same time, achieving 

national goals of effectively managed areas in its 

164 

kilometres 

0 20 40 80 120 160 

jurisdiction’s fishing areas. Noticeable declines in 

coastal resources have prompted communities in Fiji 

to take action to protect their valuable natural and 

cultural coral reef resources, specifically to replenish 

fish stocks. The FLMMA network has established 

149 LMMAs (I qoliqoli) with about 216 tabu areas 

covering 17,726 km 2 of inshore area. The community 

benefits of LMMAs and corresponding tabu areas are 

far-reaching, and explain why the LMMA community 

has expanded across the region. The success of 

LMMAs is linked with fisheries, coastal protection, 

waste assimilation, research and education, as well as 

bequest values (IUCN 2009), and is attributed more 

or less to ecological, socioeconomic, political and 

traditional culture advancements. 

Intertidal sedentary marine species in tabu 

areas 

Ecological benefits from LMMAs and associated 

tabu areas for species associated with inshore 

intertidal areas have been described in the literature. 

In the Verata district, Tawake (2004) recorded an 

approximately 20-fold increase in Anadara clam density 

in tabu areas, and about 200−300% increase in 

harvest in adjacent fished areas. Other flow-on effects 

were attributed to the tripling of fish catches, and a 

subsequent 35−45% increase in household income. 

Aalbersberg et al. (2005) detail how, in one LMMA, 

mangrove lobster (Thalassina anomala) increased by

approximately 250% annually, with a spillover effect 

of roughly 120% outside the protected area. Perhaps 

more importantly, the study describes how weekly 

household income in three Fijian communities with 

LMMAs increased by an average 43% from 2000 

to 2003. The study authors noted that ’a successful 

locally managed marine area is, in effect, an alternative 

income source. The increase in fishery resources 

not only improves nutrition but also raises household 

income through market sales’. Tawake et al. (2001) 

noted that results such as these in other places have 

led communities to establish no-take areas in the 

mangroves and coral reefs to encourage lobsters and 

coral fish production. Sedentary marine species such 

as trochus, giant clam, seaweed and sandfish have 

been the focus of other LMMAs and tabu areas in 

the Pacific islands region. 

Social and economic studies in LMMA communities 

reveal that the social cohesion among the 

community members, the perceived condition of the 

fishery resources, the condition of the terrestrial and 

village environment, the community’s understanding 

of the values of their marine environment, and 

the amount of marine resources have all greatly 

improved (Fong 2006). They also conclude that the 

average catch per unit of effort and the income level 

of fishers have increased significantly compared with 

non-LMMA communities. 

Monitoring capacity in LMMA sites 

LMMA communities, in the process of collecting 

data, gain skills and experience in simple underwater 

reef monitoring, measuring key indicator species 

that indicate the effect of their management actions. 

Communities with tabu areas in intertidal zones often 

select sea cucumber as an indicator of change, and 

carry out monitoring of their abundance. Sandfish 

(Holothuria scabra) were monitored twice in a tabu 

area and an adjacent harvest area in Navakavu in Fiji 

within a 6-month period (Meo and Mosley 2003). 

Community monitors took the lead to carry out 

surveys, analyse data and present results to be used 

for adaptive management (Figure 2). 

The tabu area had higher numbers of sandfish 

than an adjacent harvested area during both times of 

the survey. An LMMA site with its associated tabu 

area may provide the enabling environment and the 

opportunity for a cultured sea cucumber grow-out 

phase; however, there needs to be careful consideration 

of the tabu habitat type and characteristics. 

It strongly suggests that the criteria for selecting 

165 

No. sandfish per 500-m 2 transect 

80 

70 

60 

50 

40 

30 

20 

10 

0 

March 2003 

September 2003 

Tabu Non-tabu 

Figure 2. Survey results of sandfish abundance 

(no. individuals/500 m 2) in a tabu locally 

managed marine area versus an adjacent 

non-tabu harvest area 

suitable habitats are extremely important in ensuring 

that the environment supports each life-cycle stage. 

The community of Natuvu, through the technical and 

advisory support of the FLMMA network and the 


Research researchers, has taken an advanced step in 

applying aquaculture techniques combined with the 

LMMA approach (Hair et. al. 2011). The initiative 

demonstrates how restocked sandfish can be managed, 

and how the restocking was, in itself, a trigger 

to initiate such management via traditional means. 

On the other hand, it also narrows a gap in knowledge 

about how the necessary link or partnership can be 

established between the community and the investing 

partner in producing cultured organisms. 

The marine tenure system in the Pacific region is 

dynamic and contemporary. It is essential that the 

principles of good governance, including a participatory 

and inclusive approach, are upheld. The 

community-based management system provides 

flexibility to integrate traditional and science-based 

knowledge systems harmoniously. 

Resource governance in LMMA communities is 

quite pronounced compared with non-LMMA communities 

(Fong and Aalbersberg 2011). Hence, these 

communities are able to use existing arrangements 

to organise and orientate them to take the lead in 

any resource-related project such as grow-out of 

hatchery-produced sea cucumber (e.g. restocking 

or sea-ranching activities). However, input from 

technical resource organisations is essential, as most 

communities will not have the capacity to undertake 

such a project alone.

Natuvu village case study 

In Fiji, application of the LMMA approach at 

Natuvu village on the island of Vanua Levu has 

demonstrated how a customary tenure system can 

be integrated with the sea ranching of sandfish in a 

tabu area (Hair et al. 2011). In this case, a number of 

advantageous factors coincided—overseas aid funding 

and technical support, the availability of cultured 

juvenile sandfish, suitable physical conditions on the 

ground and the will of the community—to provide 

the trigger to institute such management via traditional 

means. The FLMMA network, local Fisheries 

officers, Natuvu community leaders, outside technical 

experts and local private-sector partners collaborated 

to carry out a trial sea-ranching project within 

the Natuvu tabu area. 

The project’s aim was to transfer sandfish-hatchery 

technology to local government and private hatcheries, 

increase juvenile production, and conduct searanching 

trials within a local coastal community. The 

initiative collectively engaged a range of stakeholders 

from national and local government, communitybased 

resource management advocates, the private 

sector and the community. The partnership was 

perceived as deliberate and essential in achieving the 

goal of the initiative. The juveniles produced in a privately 

owned hatchery were sea ranched in the tabu 

area in Natuvu and the communities were engaged 

in various components of the rearing processes from 

pen deployment, monitoring and enforcement. The 

community had a very strong sense of its ownership 

in the use of their I qoliqoli, and felt obliged to be 

engaged and to drive the initiative forward. The 

community-based adaptive management knowledge 

and skills of the FLMMA network engaging the 

Natuvu community over the past years was quite fitting, 

and prepared them for this aquaculture initiative. 

Although the sea cucumbers did not reach commercial 

size (due to the destructive effects of a 

cyclone), the trial demonstrated that there is potential 

for this approach to succeed. The application of the 

LMMA approach at Natuvu demonstrated how a 

customary tenure system can be integrated with the 

sea ranching of sandfish in a closed area. 

Discussion and recommendations 

Aquaculture skill and technique is still new to most 

Pacific island communities; however, a community 

in Fiji has been exposed to this activity with positive 

166 

outcomes. Although it is a relatively new activity, 

one important issue in the process is the transfer 

of knowledge and technology at different levels. 

The aquaculture stages of sea cucumber culture 

are interdependent. One stage that relies on local 

knowledge is the location of broodstock animals 

(i.e. suitably sized adults) in their fishing ground. 

The hatchery phase requires specialised technical 

expertise to conduct successful spawning and 

larval rearing. All stakeholders should have a sound 

understanding about the importance of each stage in 

the entire process. In doing so, assessment of any 

capacity gaps in acquired skills can be carried out, 

and knowledge of different stages can be established. 

Appropriate training can then be arranged. Outside 

technical assistance must be accessible when needed. 

The grow-out (or sea ranching) stage requires 

the cooperation of community members (and their 

neighbours) to allow the animals to survive and grow, 

and to resist poaching. This stage has been shown 

to be technically feasible in certain suitable areas, 

but needs to be proven economically feasible before 

proceeding. The tabu LMMA provides suitable habitat 

for culture of sandfish and, with other supporting 

evidence, these areas would be prioritised for this 

purpose. After successful research work at this stage, 

a checklist can be prepared of the conditions required 

for optimal productivity and maximum benefits for 

the sandfish in tabu sites. Technical expertise is 

required to further research these conditions. 

Community-based initiatives are often unsustainable 

in the Pacific region. This is a major issue, as 

managers and practitioners unwittingly fail to include 

community goals and aspirations in the project. 

Communities must be collectively involved, and their 

daily lives need to be influenced by the initiative in 

order to get their active participation and engagement. 

LMMAs become active sites as communities work 

their way towards setting their resource management 

governance, and establishing new management units 

in committees and corresponding provincial networks, 

the operation of which ensures the sustainability of 

projects at the local level. The main reason that communities 

engage in sea cucumber culture projects is 

for alternatives to secure their livelihood and food 

security. The communities’ expectations are raised 

once they get involved in sea cucumber aquaculture, 

and this imposes a risk if it fails to succeed. These 

factors should be studied further. 

At the moment, sandfish is commonly used because 

it is a well-established culture species (see papers in

these proceedings). However, expanding the list of 

culture species would be useful, given that most 

tabu areas comprise reefs and lagoon ecosystems. 

In Kiribati, the culture of white teatfish (Holothuria 

fuscogliva) in the hatchery has been achieved, but it is 

not known about its survival rate after release into the 

wild, since monitoring has been problematic. Further 

research into the culture and grow-out of this and 

other sea cucumber species would assist communities 

and ecosystems of the Pacific islands region, where 

tabu areas could be used to optimise management and 

provide maximum benefits. 

References 

Aalbersberg W., Tawake A. and Parras T. 2005. Village by 

village: recovering Fiji’s coastal fisheries. Pp. 144–151 

in ‘World resources 2005 – The wealth of the poor: 

managing ecosystems to fight poverty’. United Nations 

Development Programme, United Nations Environment 

Programme, the World Bank, World Resources Institute. 

Fong P.S. 2006. Community-based costal resource management 

in Fiji islands: case study of Korolevu-i-wai 

district LMMA, Nadroga. MA thesis, University of South 

Pacific, Suva, Fiji. 

Fong P.S. and Aalbersberg W. 2011. The impacts of marine 

managed areas in the social, economic and governance of 

communities in Fiji. Conservation International Marine 

Managed Area Science Program, Fiji. 

Govan H., Aalbersberg W., Tawake A. and Parks J. 2008. 

Locally managed marine areas: a guide to supporting 

community-based adaptive management. Locally- 

Managed Marine Area Network, Suva, Fiji. 

167 



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Hickey R.F. 2006. Traditional marine resource management 

in Vanuatu: acknowledging, supporting and strengthening 

indigenous management systems. SPC Traditional 

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IUCN (International Union for Conservation of Nature) 

2009. Marine protected areas case study. Navakavu 

Locally Managed Marine Area, Viti Levu Island, Fiji. 

Johannes R.E. 1998. Government-supported, village-based 

management of marine resources in Vanuatu. Ocean and 

Coastal Management Journal 40, 165–86. 

Meo S. and Mosley L. 2003. Vueti Navukavu community 

biological monitoring baseline report. Institute of 

Applied Sciences Technical Report. University of the 

South Pacific: Fiji. 

Tawake A. 2004. Human impacts on coastal fisheries in rural 

communities and their conservation approach: a case 

study on kaikoso (Anadara spp.) fishery in the coastal 

areas of Verata district, Fiji. MSc thesis, University of 

the South Pacific, Suva, Fiji. 

Tawake A., Parks J., Radikedike P., Aalbersberg W., Vuki 

V. and Salasfsky N. 2001. Harvesting clams and data: 

involving local communities in implementing and monitoring 

a marine protected area—a case study from Fiji. 

Conservation Biology in Practice 2, 32–35. 

Vierros M., Tawake A., Hickey F., Tiraa A. and Noa R. 2010. 

Traditional marine management areas of the Pacific in 

the context of national and international law and policy. 

United Nations University—Traditional Knowledge 

Initiative: Darwin, Australia.

Sandfish (Holothuria scabra) fisheries in the 

Pacific region: present status, management 

overview and outlook for rehabilitation 

Kalo M. Pakoa 1*, Ian Bertram 1, Kim J. Friedman 2 

and Emmanuel Tardy 3 

Abstract 

A regional comparative assessment of reef resources and socioeconomic activities of fisheries in 17 Pacific 

island countries and territories (PICTs) conducted by the Secretariat of the Pacific Community (SPC) over 

an 8-year period (2002–09) reveals useful resource status information. Here we review the status of sandfish 

(Holothuria scabra) stocks from a range of PICTs, some of which have had a moratorium on commercial 

exports for many years. Holothuria scabra was present in 41% of countries and 23% of sites assessed, 

although sites with sandfish were mostly at low density, with 81% below the mean density of 1,200 individuals/ha, 

and the majority of sandfish were small (

There is also concern by fisheries managers and 

governments, because these easily accessible, inshore 

resources are often no longer able to return economic 

benefits to remote and rural communities that have 

few other options for income generation. Sea cucumbers, 

which are generally exported in their dried 

form (beche-de-mer) to Asian markets, are one of 

the oldest commercial export commodities for many 

PICTs. Some sea cucumber species are also a local 

source of protein for the Pacific island communities. 

Where subsistence fishing was important, domestic 

commercial activities have often developed to support 

demand of this local delicacy. These domestic 

sales fit the definition of commercial fisheries, but 

are normally not classified in standard recordings 

of commercial activity. Instead, they are classed as 

subsistence fishing, which is normally exempted from 

formal legislation and controls. 

Production of sea cucumbers in the region varies 

depending on the size and nature of the island and 

the coastal systems of each country. The high island 

lagoon systems found in Melanesia dominate production, 

with Papua New Guinea (PNG) (600 t), Solomon 

Islands (400 t), Fiji (200 t) and New Caledonia 

(Kinch et al. 2006, 2008) producing the bulk of commercial 

products. PNG, the single most important 

producer, was supplying approximately 10% of world 

production before a moratorium on its fishery was 

declared in late 2009. Due to unregulated take and 

degradation of stocks, other countries have taken 

similar actions: Palau in 1994 (>10 years), Samoa 

(1994 to present), Tonga (2007 for 10 years), Vanuatu 

(2008) and Solomon Islands (2005). Historical 

time-series show that sea cucumber fisheries in the 

Pacific region have been characterised by boom and 

bust cycles (Uthicke 2004). High production since 

the 1990s to early 2000 represents the latest fishery 

‘boom’ across the Pacific, and now the region is going 

through the ‘bust’ cycle, which has resulted in a number 

of moratorium declarations in the past few years. 

A regional comparative assessment of reef 

resources and socioeconomic activities of fisheries 

from 17 PICTs conducted by the Secretariat of the 

Pacific Community (SPC) over an 8-year period 

(2002–09) reveals useful resource status information 

not readily available in the past (Friedman et al. 

2010). Here we review the stock and management 

status of sandfish stocks from a range of PICTs. 

We use snapshot data to compare spatial distribution, 

abundance and size distribution of sandfish 

(Holothuria scabra) stocks across multiple sites in 

169 

five of the seven countries studied between 2002 and 

2009. In addition, we look at the status of golden 

sandfish (H. lessoni) in Tonga, where sandfish is 

naturally absent and golden sandfish is a species of 

potential interest for aquaculture development. 

Regional, national and state 

legislative control 

At present there is no regional agreement about the 

management of sea cucumber fisheries in the Pacific 

region (Friedman and Chapman 2008). National 

regulations control the species harvested, and the 

amount and size of sandfish exported (Table 1), 

although subsistence fishing and fishing for the local 

market are not well monitored or controlled. 

Community-based management 

Community-based management via customary 

marine tenure (CMT) in the Pacific islands region is 

an effective framework for sustainable management 

of marine resources. Reef invertebrate resources 

such as sea cucumbers can be managed effectively 

by CMT systems; however, progress in communitybased 

marine resources management in recent years 

has done little to reverse the declining trend in sea 

cucumber fisheries. Customary resource tenure gives 

villages, clans or communities the right of ownership 

to the land or coastal areas where they live, or over 

which they have ancestral claims. These rights were 

in place prior to colonisation and are often recognised 

in national legislation (Table 2). A lot of attention and 

financial support have been given to community-based 

management in the past decade to strengthen local 

governance of resources (see Meo 2012). The goal is 

to delegate and empower some management responsibility 

to resource custodians, thereby relieving pressure 

on government, especially on the difficult roles 

of surveillance and enforcement. Customary management 

is promoted also as a means of preserving local 

traditions and cultural practices by recognising and 

supporting local governance structures. 

Survey results 

Here we review the survey data for sandfish stocks 

from a range of PICTs, some of which have had 

moratoriums on exports for up to 10 years. Snapshot 

data across sites in 17 SPC member island countries 

and territories were used to compare spatial

Table 1. Government regulation of sandfish stocks in Pacific island countries 

Country Commercial/subsistence 

extraction 

distribution (presence), abundance (density) and size 

distribution of stocks over an 8-year period, 2002–09. 

Sandfish stock status was assessed by shallow water, 

soft-benthos transect surveys. General fishery 

information was collected through discussions with 

fisheries officers, processors, exporters and fishers 

during visits. All data were entered into the Reef 

Fisheries Integrated Database at SPC in Noumea. 

Survey data are analysed and presented as ‘presence’ 

(percentage of total replicate transects) as a measure 

of spatial coverage; density (individuals (ind)/ha) as 

a measure of abundance; and total length (cm) as a 

measure of size. 

Sandfish was present in seven PICTs, where 

the species is endemic, and golden sandfish was 

Individual 

species controls 

Palau Subsistence/commercial Commercial 

export ban 

Fiji Subsistence/commercial Commercial 

export ban 

170 

Size/weight controls Export licence 

required 

None – 

76 mm dry length – 

Vanuatu Commercial None None Yes–no limit 

New Caledonia Commercial None None Yes–no limit 

Tonga Commercial (golden sandfish) Commercial 

export ban 

70 mm dry length – 


Micronesia 

Commercial None None Yes–no limit 

Solomon Islands Commercial None 100 mm dry length Yes–no limit 

Papua New Guinea Subsistence/commercial None 100 mm dry length Yes–no limit 

Table 2. Status of customary resource tenure in selected Pacific island countries in relation to sandfish stocks 

Country Commercial / 

subsistence extraction 

Palau Subsistence domestic 

sale 

Fiji Subsistence domestic 

sale 

Strength of village 

management a 

Customary marine 

tenure (CMT) 

Strong Strong Weak 

Moderate Strong Weak 

CMT supported in 

national legislation 

Vanuatu Commercial Variable Strong Weak 

New Caledonia Commercial Moderate No ? 

Tonga Commercial (golden 

sandfish only) 

Absent No No 


Micronesia 

Commercial Low Yap state Yes–Yap state 

Solomon Islands Commercial Low Moderate ? 

Papua New Guinea Domestic/ 

commercial 

Low Moderate ? 

a perception of survey personnel 

present only in Tonga. Of all the sites where sandfish 

and golden sandfish occurred, 44% had suitable 

habitat for sandfish (soft bottom substratum with 

seagrass, often with mangrove influence). The best 

sites where sandfish were present were Ngatpang, 

Ngarchelong and Airai (Palau), Maskelynes 

(Vanuatu), Riiken (Federated States of Micronesia), 

Dromuna, Muaivuso and Lakeba (Fiji), Oundjo 

(New Caledonia), Tsoilaunung and Andra (PNG), 

and Nggela (Solomon Islands), while golden 

sandfish was present in Ha’atafu and Nukunuku 

(Tonga). Density results for these sites (Figure 1) 

reveal that most sites held densities that were characteristic 

of an impacted stock (71% of sites had a 

mean density of below 942 ±156 SE ind/ha), and

60% of the sites recorded a mean of 23 cm size) is highly likely to be lost 

due to continuous exploitation by the subsistence 

and domestic-market sectors, and there is also 

significant export of raw sea cucumber to Palauans 

living overseas. Distance from the market, presence 

of marine protected areas (MPAs) and lower fishing 

pressure contributed to the more healthy stocks in 

the northern states. However, fishing controls of the 

domestic-market sector are still needed to prevent 

further depletion of the resource. 

Holothuria scabra or ‘dairo’ is a local delicacy in 

Fiji. Three sites that had sandfish—Muaivuso, Lakeba 

and Dromuna—assessed twice in this study, provided 

valuable insight into resource status over two time 

FSM = Federated States of Micronesia; 

PNG = Papua New Guinea 

Mean density at 942 individuals/ha 

Palau-Airai 

Fiji-Lakeba 

PNG-Tsoilaunung 

Tonga-Haatafu 

Solomon Is.-Nggela 

PNG-Andra 

Figure 1. Density of sandfish (individuals/ha) in the 14 best sandfish sites in the Pacific region 

Fiji-Nukunuku

periods. As in Palau, commercial export of dried H. 

scabra is banned in Fiji (since 1988), but harvesting 

for subsistence use, which includes domestic sales, 

is exempted from this regulation. Two of the three 

sites assessed in Fiji that had H. scabra (Lakeba and 

Muaivuso) had MPAs established, but they do not 

cover sandfish habitats. The density of H. scabra 

decreased across all sites between 2003 and 2009 

by 54%, 51% and 36% for Dromuna, Muaivuso and 

Lakeba, respectively (Figure 2). 

In the Northern province of New Caledonia, 

sandfish density was high, with a mean density of 

1,784 ± 203 SE ind/ha. Interestingly, the area surveyed 

was split by the size of individuals recorded 

between an area within an MPA and an area that had 

more open access. The larger and older individuals 

(mean length 22 cm) were found in the MPA, while 

the smaller and younger individuals (mean length 

14 cm) were recorded in the open access area. 

In Vanuatu, customary management is widely used 

to protect inshore resources. In the Maskelyne Islands, 

South Malekula, H. scabra fishing had been banned for 

some years prior to the surveys, and there is no subsistence 

use of sandfish. The study revealed the presence 

of good stock densities (2,202 ± 296 SE ind/ha) and a 

relatively healthy population, with sizes in the range 

6–32 cm length. There is no subsistence exploitation 

of sandfish, which is an advantage in that the community 

have to manage only the commercial aspect of 

the fishery. In addition, Maskelyne Islands is remote 

to the main island of Efate, where there are greater 

commercial pressure and incentives. 

In Tonga, sandfish is naturally absent and golden 

sandfish is featured strongly as a local delicacy. The 

golden sandfish is exploited for subsistence but, 

Density (individuals/ha) 

700 

400 

300 

200 

100 

0 

172 

more importantly, in domestic commercial sales 

of processed meat and guts, which are sold at the 

local market. Resource surveys conducted by SPC 

(K.J. Friedman, unpublished data; Friedman et al. 

2008) revealed the presence of golden sandfish in 

the three island groups of Tongatapu, Ha’apai and 

Va’vau; however, densities are patchy, suggesting 

that stocks may have been overharvested. Anecdotal 

reports (Charly Valentine, pers. comm.) indicate that 

this species was one of the main products exploited 

in the 1990s. The golden sandfish stock of Tonga is 

struggling to recover after this exploitation and the 

continued additional pressure from subsistence and 

domestic commercial fishing activities. 

Resource management status 

From this stock status information and existing 

management measures, we are able to suggest 

improvements in current PICT management systems 

to ensure that there is sustainable management or 

rehabilitation of sandfish resources. 

Where sandfish is not important in the local diet, 

subsistence and domestic commercial pressures don’t 

exist, simplifying the issue of management for legislators. 

However, the trend of resource depletion being 

experienced at sites surveyed in this study shows that 

both subsistence and domestic commercial sales are 

depleting sandfish resources across the Pacific region. 

Existing national and local management regimes are 

not reversing the trend of declining spatial availability, 

abundance and size in the sea cucumber fishery. 

For most island countries, the existing national and 

local (province or state) sea cucumber management 

regimes are not well aligned to ensure maximum 

600 2003 

500 

2009 

Muaivuso Lakeba Dromuna 

Figure 2. Density of sandfish (individuals/ha) in three sites assessed in Fiji between 

2003 and 2009

protection of resources, the socioeconomic needs of 

the population and the customary practices of managing 

resources. We believe that having comprehensive 

enforceable fishery management plans, and accompanying 

regulatory frameworks, for each country 

can provide managers and community leaders with a 

good basis for management. 

The 12-year moratorium on harvest of H. scabra in 

Palau has been successful in controlling commercial 

export of the species; however, the policy is not working 

effectively to improve the status of the resource, 

as larger sandfish with greater reproductive capacity 

are being removed by the domestic commercial fishery. 

Continuous depletion of the population through 

fishing could result in stocks of predominantly young 

animals (i.e. less breeding capacity), possibly leading 

to poor or erratic recruitment. Domestic commercial 

sale is proving to be the major contributor to the 

depletion of H. scabra in Palau, and development 

of regulations and policies are a matter of priority to 

control the fishery. 

In Fiji, where sandfish is a local delicacy, both subsistence 

and domestic commercial activity exist. In a 

similar situation to Palau, Fiji has banned commercial 

export of sandfish (Fiji Fisheries Act 1991), while 

subsistence and domestic commercial sales remain 

unregulated. Domestic commercial selling is classed 

under subsistence activity and thus is exempted from 

fisheries regulations. MPAs established by communities 

do not usually include H. scabra habitat 

(i.e. shallow, soft-bottom substratum) or, if they do, 

community enforcement of the MPAs is not working 

effectively in the sites assessed by this study. 

It is recommended that the national and provincial 

fisheries authorities take action to regulate domestic 

commercial exploitation of H. scabra, which is currently 

contributing significantly to the pressure on 

the resource. 

In New Caledonia, national and provincial control 

on the sea cucumber fishery is working relatively 

well, with control systems partially protecting 

resources and controlling fishing pressure. Sandfish 

continue to be fished commercially for export, and it 

is the third-most important species fished in terms of 

quantity (Purcell et al. 2009). Putting limits on export 

licences is an effective tool to control exploitation 

and encourage responsible fishing. Moreover, this 

does not stop communities from setting aside parts 

of their lagoon area as MPAs. Therefore, as shown in 

this study, having an effective national control of the 

fishery provides a healthy environment for MPAs to 

173 

operate. Where an MPA is not effective in improving 

recruitment, stricter harvesting conditions on size and 

quality may be needed in addition to a national closed 

season. 

In Vanuatu, a moratorium was enforced in 2008 as 

a result of concerns about unsustainable harvesting. 

Community-based management was the principle 

form of control used by rural communities, while 

the Fisheries Department controlled the exit point 

of export. Customary management of tabu areas, 

as used in the Maskelyne Islands, was previously 

effective in managing the H. scabra resource. 

However, the lack of a national sea cucumber fishery 

management policy, monitoring protocol and associated 

regulations are existing weaknesses that make 

it difficult for authorities to control the industry. 

In one particular case, a community was lured by 

a foreign ‘trader’ into giving up their resource in 

exchange for a promise to reseed their reefs with 

juvenile cultured H. scabra (imported seed stock). 

This venture cost the community most of their wild 

stock, and did not result in the successful grow-out 

of seeded juvenile sandfish. Customary marine 

tenure is an effective management tool, but there are 

limitations to the scope of social law in the context 

of controlling fishing of sea cucumbers. In the case 

of social law, as experienced in the Maskelynes, the 

commercial nature of the fishery is changing rapidly, 

and is therefore relatively difficult to control. Lack 

of knowledge of the fishery, and introductions of 

new aquaculture opportunities with no proven track 

record, combined with weak national and provincial 

fishery control systems, were some of the factors 

contributing to management failure. A national 

fishery policy and additional regulations are needed 

to strengthen control and limit exposure of communities 

and their management systems to these external 

market pressures. 

In Tonga, where sea cucumbers are a local delicacy, 

several species are exploited for subsistence and 

domestic sale. Among the locally exploited species 

is golden sandfish, a high-value species of great 

importance to Tonga. The species was also important 

in the commercial export trade in the 1990s, with 

Tongatapu yielding most of Tonga’s golden sandfish 

production (according to anecdotal reports from 

export agents) prior to the 1997 moratorium. While 

the moratorium on golden sandfish was extended in 

recent harvest seasons, lack of control on domestic 

sale activities continue to impede the recovery of its 

stocks in Tonga.

Aquaculture and the management 

of sea cucumbers 

Sea cucumber aquaculture may provide options for 

restocking, stock enhancement and sea ranching to 

restore depleted populations and rebuild stocks to 

commercially viable levels (Bell and Nash 2004; 

Bell et al. 2008). However, while these technologies 

are being developed and refined to determine the best 

strategies, wild harvesting continues unabated, and 

there is significant anticipation and expectation by 

communities that aquaculture will save the fishery. 

The promise of aquaculture development in the 

Pacific region has been used as a tool to access and 

further exploit wild resources. The effects have been 

both direct—through the fishing of broodstock—and 

indirect—through ‘trial harvesting and clearing, to 

prepare the ground for seed’, which speeds up adult 

decline and habitat degradation. 

Many fishers and managers in PICTs lack basic 

knowledge of sea cucumber biology and aquaculture 

technology. Sea cucumber fishers, resource owners 

and fisheries managers have been exposed to promises 

of huge profits from sea cucumber aquaculture 

via restocking of imported hatchery-reared juveniles 

(e.g. Vanuatu, Figure 3a); artificial splitting and sea 

ranching of sea cucumbers (e.g. Marshall Islands, 

Figure 3b); hatchery development and reseeding; 

and aggregation of broodstock to aid spawning as a 

form of stockpiling of sea cucumbers before the next 

harvest season (Figure 3c). 

One main concern is that traders promote such 

ideas in order to obtain access to wild stocks 

through both the upper levels of management and 

the community. Following such experiences, advice 

was disseminated by SPC to assist decision-makers 

in making the best choices for sea cucumber aquaculture 

development in their countries (e.g. SPC 

2009): 

1. Under no circumstance should investors in a 

hatchery, and sea ranching or restocking, be 

permitted to engage in fishing of the wild stock. 

2. Sea-ranching projects must be governed by 

robust partnership arrangements with resource 

owners. 

3. Investors must employ qualified hatchery staff to 

conduct the breeding and sea-ranching activities. 

4. Hatchery-reared animals must be released into 

defined areas, and harvesting operations must 

NOT involve collection from areas outside these 

defined areas. 

174 

5. The harvest size of sea-ranched animals should 

be above the size at first maturity, to allow spawning 

before harvest. 

6. Sea-ranched sea cucumber should be clearly 

distinguished from wild sea cucumber. 

7. Broodstock should be sourced from local stocks. 

8. Importation of broodstock and juveniles should 

NOT be permitted. 

9. Investors for sea cucumber hatcheries should bear 

the cost of proving the social and commercial 

viability of their operations. 

10. Investors should provide evidence of their capital 

commitment to do the research. 

11. Cutting up of animals for sea ranching is not 

a recommended aquaculture technology, and 

should never be promoted. 

12. Aggregation of broodstock to encourage spawning 

should not be used as a means to stockpile 

resources for harvest in the next open season. 

Discussion 

Although both customary marine tenure and fisheries 

regulations seek to manage the sandfish resource, 

there are limitations to the scope of both social and 

government law in the context of controlling fishing 

of sea cucumbers. In the case of social law, the 

commercial nature of these fisheries is relatively difficult 

to control, as witnessed by the differing range 

and level of adherence to social controls across the 

Pacific region. Equally, fisheries regulations are only 

effective when fisheries agencies have the resources 

to implement comprehensive controls. These are 

difficult to implement across the scales at which 

the fishery operates, and inoperable for subsistence 

fishing. To be effective, managers need baseline 

information on the status of resources and fishery 

levels, coupled with ongoing monitoring. 

Sea cucumber is one of the oldest fisheries in the 

Asia–Pacific region, yet it is one of the least well 

managed. Many island countries do not have proper 

national, provincial or state sea cucumber fishery 

management policies or plans. Where such policies 

exist, regulations to enforce them are not developed, 

making enforcement difficult. Most PICT legislation 

is not reviewed regularly to adjust to changes and new 

developments of the fishery; for example, aquaculture 

and sea-ranching developments are relatively new 

initiatives, and are unlikely to be included in legislation. 

Aquaculture, restocking and sea ranching are 

management options that require further refinement

(a) 

(b) 

(c) 

Investor 

Wild 

stock 

Hatchery 

produced 

baby cucs 

$ $ 

$ $ 

$ 

$ 

Figure 3. SPC educational material warning PICT fisheries and aquaculture managers of the risks associated with 

(a) restocking of imported hatchery-reared juveniles in exchange for harvest of wild stocks; (b) artificial 

splitting and sea ranching of sea cucumbers and (c) aggregation of broodstock to aid spawning as a form 

of stockpiling (illustrations by Youngmi Choi, SPC) 

before they are given wide-scale promotion in the 

region. Additional research is needed to fully test 

techniques. Private-sector aquaculture activities must 

be monitored to ensure environmental and social 

responsibility at all times. 

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United Nations: Rome.

Market potential and challenges for 

expanding the production of sea cucumber 

in South-East Asia 

Maripaz L. Perez 1* and Ernesto O. Brown 2 

Abstract 

Sea cucumbers are fished worldwide, with more than 50 species commercially exploited. In South-East 

Asia, important sources of sea cucumber are Indonesia, the Philippines, Vietnam, Thailand and Malaysia, 

with Singapore and Hong Kong being major export destinations. The product is popular among oriental 

consumers due to its alleged ability to improve vigour and cure a number of ailments. Supply in South-East 

Asia is declining due to overfishing. While significant volume is being produced from sea ranching and 

pond culture, this is not enough to offset rapidly declining collection from the wild. This and the increasing 

demand for the product have kept prices at attractive levels. Nevertheless, high prices do not translate to 

improved income for coastal households as individual catch size remains small and the cost per unit of 

fishing effort high. The market offers high premiums for well-dried, good-quality sea cucumber. However, 

primary processing, which is the sole determinant of product quality, remains mostly at the village level, 

which employs traditional practices. The nature of the fishery itself, which is characterised by small catch 

volumes per day, leads to diseconomies of size, constraining large processing facilities that are compliant 

with ‘good manufacturing practice’ (GMP) and ‘hazard analysis critical control point’ (HACCP) standards 

from engaging in the business. The market also operates in the absence of officially formulated grades and 

standards that would guide transactions along the value chain. 

The marketing system for sea cucumber in South-East Asia is generally inefficient, and marketing channels 

are multilayered. Information asymmetry encourages proliferation of redundant players in the distribution 

system, while high transaction costs keep the overall marketing margin high but the price received by 

collectors low. Unlocking the full potential of the sea cucumber industry calls for a set of well-conceived 

strategies that would sustain supply from the wild, increase the supply from aquaculture, improve primary 

processing and remove the inefficiencies in the distribution system. Emerging systems for more-efficient 

processing of the product should also be explored to address issues of economies of scale and improve returns 

on investment for GMP- and HACCP-compliant facilities, as well as the incomes of fishers and farmers. 

Introduction 

Marketing systems cover supply, demand and prices. 

Simple as it may seem, the complication becomes 

apparent when one considers that analysis of supply 

includes a range of concerns, from collection of the 

1 WorldFish Center, Los Laguna, Philippines 


2 WorldFish Center / Socio-Economic Research Division, 

PCARRD, Los Laguna, Philippines 

177 

product to processing and distribution. In addition, 

supply is not only about quantity, but quality as 

well. Similarly, analysis of demand covers a wide 

array of interests. Of particular importance are the 

geographical characteristics of demand, the nature 

of products demanded, specific product requirements 

and the trend in volume resulting from changes in 

taste and preference. Price may be viewed as the 

result of interaction between demand and supply. In 

a capitalist economy, the price system determines 

what, how and how much of a given commodity to

produce. Price trends provide a snapshot picture of 

overall industry trends. 

Since the marketing system covers supply, demand 

and prices, consideration of attendant issues crucial 

to each component is inevitable. In the case of sea 

cucumber, overexploitation is a crucial supply issue, 

as are inefficiencies in processing and distribution. 

Also important are issues on grades and standards, 

such as the application of ‘good manufacturing 

practices’ (GMP) and ‘hazard analysis critical 

control point’ (HACCP) methods. On the demand 

side, globalisation of demand and the increasing 

number of new sea cucumber products are interesting 

developments. Of course, supply and demand issues 

cannot be viewed in isolation. Understanding how 

one affects the other is at the core of a good marketing 

system analysis. 

This paper is limited to establishing the major 

features of the marketing system for sea cucumber 

in South-East Asia. The opportunities and challenges 

associated with this system, especially in 

relation to expanding production in response to a 

growing demand, is the primary focus. The potential 

for aquaculture is also explored. The paper uses 

secondary data on production and marketing, as 

well as information/data generated from relevant 

studies conducted in the Philippines, Vietnam and 

Hong Kong. The paper also provides a synthesis of 

results and discussion from available literature on 

the subject. The first section outlines the marketing 

system, particularly in terms of features common 

to countries in South-East Asia. The second section 

discusses the marketing opportunities and challenges 

to expanding sea cucumber production in the region. 

The third section provides a synthesis of common 

marketing issues, and offers a set of recommendations 

on how to explore the opportunities, overcome 

the challenges, and deal with the various issues 

plaguing the sea cucumber industry in the region. 

Major characteristics of the 

marketing system for sea 

cucumber in South-East Asia 

The marketing system for sea cucumber in South- 

East Asia can be characterised in terms of the three 

fundamental components: supply, demand and price. 

Supply includes collection from the wild and production 

from ponds, but is not limited to these. All 

activities related to processing and distribution of the 

178 

sea cucumber products available to consumers are 

also viewed in this paper as part of supply. Demand 

is assessed in terms of the utility derived in consumption 

as well as in terms of its spatial and temporal 

nature. Characterisation of the marketing system in 

terms of price is limited to analysis of premium price 

for quality, price spreads and price trends. 

Supply-related marketing system 

characteristics 

There are a number of common threads that run 

across countries in South-East Asia when it comes to 

supply-related marketing system characteristics for 

sea cucumber. Most countries in the region are major 

sources of sea cucumber products, and the species 

profiles are more or less the same since the countries 

have a similar tropical environment. Collection 

from the wild is generally marginal, and carried out 

mostly by low-income households in coastal villages. 

Primary processing remains traditional, and processing 

techniques are generally the same across the region. 

Overexploitation of high-value species is a common 

problem, with each country pursuing specific initiatives 

to address the problem. Finally, almost all countries 

are exploring aquaculture as a significant supply 

source to improve the incomes of coastal households 

and lessen the pressure of overfishing in the wild. 

South-East Asia is a major source of sea cucumber, 

with Indonesia, the Philippines and Malaysia among 

the top producers in the region. Despite the increasing 

demand and high price for the product, sea cucumber 

fisheries are mostly artisanal, with sea cucumber just 

an incidental catch to finfish. However, fishing activities 

where sea cucumber are targeted appear to have 

significantly grown during the past few years. 

Recent reviews of the state of sea cucumber fisheries 

in South-East Asia showed alarming increases in 

fishing pressure. Overexploitation has led to local 

extinction of high-value species in some localities, 

and prompted closure of many national fisheries to 

allow stocks to recover, and to allow more sustainable 

management plans to be established (Purcell 

2010). In the Philippines, the Bureau of Fisheries and 

Aquatic Resources (BFAR) considers sea cucumber 

to be a heavily exploited resource, and acknowledges 

that localised depletion has occurred in many fishing 

grounds. But BFAR possesses no quantitative census 

to support this claim (Gamboa et al. 2007). 

In response to overfishing and declining catches, 

and spurred by high international prices, aquaculture, 

sea ranching and restocking have been attempted

in a number of countries (Macfadyen et al. 2009). 

The Australian Centre for International Agricultural 

Research (ACIAR) and the Worldfish Center are 

among the international organisations leading 

the development of sea cucumber aquaculture in 

South-East Asia. Hatchery and nursery protocols for 

high-value species, particularly Holothuria scabra 

(sandfish) are fairly well developed in the Philippines, 

Vietnam, Malaysia and Indonesia. Existing methods 

for sandfish grow-out include pond and pen culture 

as well as sea ranching. 

Primary processing 

In the Philippines, village assemblers are the ones 

who typically carry out primary processing. It is 

tedious and time consuming, and generally involves 

gutting, boiling, brushing, smoking and sun-drying 

(Brown et al. 2010). However, the processing steps 

depend on the species being processed, and techniques 

vary from place to place. Most collectors sell their 

collection fresh to assemblers or processors, while 

some process the sea cucumbers themselves before 

selling them to assemblers, processors or other traders. 

In southern Thailand, processing of sea cucumber 

involves gutting and boiling the animal in sea water 

for 1 hour. The fishermen then bury them in the sand 

overnight, before removing them and stepping upon 

them for 10–20 minutes to squeeze out their colour. 

The sea cucumbers are boiled again in water for 

1 hour, then brushed to remove the spicules, before 

they are ready for consumption or dried for storage. 

Primary processing of sea cucumbers in South- 

East Asia will likely remain traditional, small scale 

and limited at the village level. The nature of the 

fishery, which is widely dispersed and where daily 

collection volume from source villages is small, 

would not warrant economies of scale in processing. 

In Vietnam, a large processing company dropped sea 

cucumber from its processed product line because 

insufficient volume to achieve economies of scale 

could be sourced locally. A detailed example of the 

processing method employed in the Philippines, as 

well as the associated costs, is shown in Table 1. Total 

cost is PhP248 (about US$6) for 12 kg of product. 

Distribution system 

Sea cucumber production in South-East Asia is for 

both domestic consumption and the export market 

(SEAFDEC 2009). However, the significance of the 

local compared with the export market varies significantly 

by country. Countries with small local demand 

179 

include the Philippines, Indonesia and Cambodia 

(see Labe 2009; Sereywath 2009; Wiadnyana 2009), 

where the bulk of production is exported and other 

consumption is limited to local Chinese residents. 

Significant local markets exist only in Vietnam and 

Malaysia. 

The general product flow for sea cucumber 

involves fishers, village assemblers and processors, 

other local traders in the source areas, and exporters 

generally located in big cities (Figure 1). Fishermen 

sell the product to the collector or buyer either 

fresh or dried. Buyers also directly collect dried sea 

cucumber from fishers who opt to dry the products 

themselves. In the Philippines, though, village-level 

assemblers and processors do exist. They either wait 

at the landing sites to buy fresh sea cucumber, or 

the fishers themselves bring the catch to them. A village 

assembler carries out the primary processing, 

and stores the dried product until sufficient volume 

is accumulated for sale to exporters in the capital, 

Manila, and other big cities (Figure 2). 

In Malaysia, sea cucumbers are sent to both 

domestic and international markets, although a small 

portion of fresh product is sold at fish markets for 

consumption by the local Chinese population. The 

domestic market also includes sales to processors 

for producing traditional medicines and other healthrelated 

products (Ibrahim 2009). However, a major 

proportion of sea cucumber in Malaysia is exported. 

In Vietnam, sea cucumber markets include dried and 

frozen product, although the volume of the latter is 

relatively small. Dried sea cucumbers are distributed 

to either domestic or overseas markets. 

There are at least 635 firms involved in supplying 

sea cucumber products all over the world (Table 2). 

Typically, sea cucumber is one line in a variety of 

fishery and other agricultural products supplied. 

In the Philippines, supplier firms are engaged with 

a long list of high-value marine and agricultural 

products, including abalone and shark fin. Among 

South-East Asian countries, Indonesia has the largest 

number of firms (81) supplying sea cucumber products, 

followed by Malaysia (61) and the Philippines 

(50). There are 21 supplier firms in Vietnam, while 

Thailand has 9. Along the sea cucumber supply 

chain, supplier firms are among the downstream 

players responsible for bringing the products to both 

local and international consumers. 

There are limited studies on the efficiency of the 

sea cucumber distribution system in South-East Asia. 

However, a recent study conducted in the Philippines

Table 1. Steps involved in processing sea cucumber, the corresponding resources needed, and the associated 

costs (Palawan processors, the Philippines, 2010) 

STEPS RESOURCES NEEDED COSTS (PhP/day) 

1. Gutting at the mouth Petromax or lamp 

Flashlight 

Gasoline or kerosene 

Knife (good for 3 years) 

2. Boiling for 5 minutes 

– 2 hours 

3. Mixing with papaya leaves 

for 1 hour 

180 

Average Minimum Maximum 

2.17 

0.28 

44.00 

0.03 

1.85 

0.28 

33.00 

0.06 

2.78 

0.28 

54.00 

0.06 

Aluminium basin or big pan 

(good for 1–3 years) 

0.63 0.32 1.11 

Scoop made of net (good for 7 months) 0.29 0.29 0.29 

Pail (good for 1 year) 0.23 0.19 0.28 

Papaya leaves (can ask children to collect) 1.00 1.00 1.00 

4. Boiling with salt for 1 hour Match 1.00 1.00 1.00 

Salt 7.50 5.00 10.00 

Water 5.00 5.00 5.00 

5. Brushing to remove outer 

layer (spicules) 

Used laundry brush or toothbrush - - - 

6. Smoking for 1–24 hours Wood (for both boiling and smoking) 7.50 5.00 10.00 

Screen 0.33 0.33 0.33 

7. Sun-drying for 3–5 days 

until ‘stone dry’ 

Galvanised iron 0.06 0.06 0.06 

8. Packing in plastic bag 

(holding until desired volume 

is attained, 2.5–5.0 kg) 

Plastic cellophane 

(100 pc × PhP0.5–2.0/pc) 

125.00 50.00 200.00 

9. Transporting (tricycle) Fare (to buying station and back) 44.00 44.00 44.00 

TOTAL 

Source: Brown et al. (2010) 

239.02 147.39 330.19 

Local trader 

International market 

Local trader 

Non-processing 

Local consumption 

City trader City consumer 

Figure 1. Typical product flow of sea cucumber in South-East Asian countries. Source: SEAFDEC 

(2009)

Commission 

agent 

1– 3 

days 

1–7 

days 

International 

market 

(direct importer) 

Hong Kong, 

Singapore, China 

(mainland), 

South Korea, 

Japan, Taiwan, 

2–4 months 

Figure 2. Product flow of sea cucumber in the Philippines. Source: Brown et al. (2010) 

(Brown et al. 2010) showed that it appears to be 

multilayered and characterised by information 

asymmetry. Redundant market players such as agents 

proliferate, and are engaged in pure arbitrage (i.e. 

taking advantage of a price difference between 

multiple markets). Collectors, the most upstream 

players in the chain, are generally not aware of the 

price of sea cucumber at the downstream end, leading 

to inefficient pricing mechanisms and inequitable 

distribution of profits along the chain. 

The sea cucumber industry is like an hourglass— 

large at each end and narrow in the middle. The 

number of upstream players is very large because 

collection takes place in so many coastal areas in 

the country. In contrast, the number of downstream 

players is fairly small. In the Philippines, there are 

only 45–50 firms involved in sea cucumber trade, 

four of which are very large and account for the bulk 

of the products moving along the value chain. The 

situation in the Philippines is similar to other countries 

in South-East Asia, particularly Indonesia and 

Vietnam. Interviews with traders in Vietnam indicate 

that two or three large buyers typically account for 

Diver/collector 

Village assembler/processor 

Provincial buying station of 

exporter 

Exporter 

181 

6–8 

hours 

6–8 days 

4–15 days 

1–3 

days 

Local trader 

1–3 

days 

Domestic market 

(Aranque or 

Manila China Town 

and hypermarts in 

provincial cities) 

the bulk of sea cucumber outputs in districts where 

a large volume is collected. However, the number of 

key Chinese customers catered to by existing supply 

chains is very large. 

This suggests that industry control is in the hands 

of a few large exporters, who capture much of the 

value generated by the industry. In the Philippines, 

the net income of an exporter from a kilogram of 

H. scabra could reach more than PhP1,000 (Table 3). 

This becomes even more significant considering the 

volume that passes through each exporter’s business. 

Their power and influence along the entire chain 

becomes apparent on closer examination. Large 

exporters have established a vast network of buying 

stations, agents and relational marketing with assemblers 

and processors. 

Value-chain mapping of sea cucumber in the 

Philippines showed the specific activities, associated 

costs and income received, as well as the opportunities 

and constraints faced by the upstream and downstream 

players along the chain (Brown et al. 2010) 

(Figure 3). Although similar studies are unavailable 

for other South-East Asian countries, the situation is

Table 2. Number and percentage of sea cucumber supplier firms by country 

Country No. of 

supplier firms 

Table 3. Cost and return, per kg of high-quality H. scabra, to various sectors of the Philippine supply chain 

Item Collector 

(fresh product) 

probably true also for Indonesia, which has a similar 

distribution system. A quick survey conducted by the 

authors also confirmed similarities with Vietnam, 

where a more detailed value-chain analysis is currently 

being prepared. 

The Philippine study showed that collectors 

receive the lowest net income from every kilogram 

of sea cucumber, particularly H. scabra, while the 

net incomes of village-level assemblers, processors 

% Country No. of 

supplier firms 

Indonesia 81 12.76 Australia 7 1.10 

Malaysia 61 9.61 Cameroon 7 1.10 

United States 55 8.66 Taiwan 7 1.10 

Philippines 50 7.87 United Arab Emirates 7 1.10 

China (Mainland) 42 6.61 Mauritania 5 0.79 

Peru 32 5.04 Mauritius 5 0.79 

Singapore 32 5.04 Morocco 4 0.63 

Vietnam 26 4.09 Pakistan 4 0.63 

Japan 25 3.94 Russian Federation 4 0.63 

Sri Lanka 21 3.31 Spain 4 0.63 

Egypt 19 2.99 New Zealand 3 0.47 

Canada 18 2.83 Colombia 1 0.16 

Mexico 18 2.83 Fiji 1 0.16 

Maldives 17 2.68 Iceland 1 0.16 

South Korea 17 2.68 Italy 1 0.16 

Turkey 14 2.20 Mozambique 1 0.16 

Hong Kong 13 2.05 United Kingdom 1 0.16 

India 12 1.89 Uruguay 1 0.16 

Thailand 


9 1.42 Total no. supplier firms 635 

Assembler/processor 

(dried product) 

182 

Exporter 

(dried product) 

Price received 300.00 4,200.00 5,364.00 a 

Cost of product 0.00 3,000.00 b 4,200.00 

Other costs c 15.07 58.21 61.67d Total costs 15.07 3,058.21 4,261.67 

Net return 284.93 1,142.00e 1,102.33 

a Based on US$120/kg @ PhP44.7/US$ 

b Based on PhP300/kg fresh (10% dry-equivalent weight) 

c Based on Tables 14, 17 and 18 in Brown et al. (2010) (note: for exporter, Aquamarine cost was used) 

d Includes PhP8.47/kg cost (see Table 18 in Brown et al. (2010)) plus PhP0.70/kg shipment cost to Hong Kong (i.e. PhP7,000/10,000 kg) 

and opportunity cost of procurement capital of PhP52.50 (i.e. PhP4,200 × 1.25%/month) 

e Includes all costs in Table 17 in Brown et al. (2010) plus opportunity cost of procurement capital of PhP37.50 (i.e. PhP3,000 × 1.25%/ 

month) 

and exporters are considerably higher. The study also 

confirmed that various players along the distribution 

system are already facing the problem of declining 

volume and increasingly smaller catch size. 

Increasing price and vibrant demand for the product 

remain as the most important opportunities available 

to these players. Aquaculture appears to be the most 

viable solution to halting the declining supply. 

%

DIVER/COLLECTOR 

Demand-related marketing system 


PROCESSOR 

Figure 3. Value-chain mapping of exported sea cucumber, the Philippines. Source: Brown et al. (2010) 

Demand for sea cucumber comes mainly from the 

middle and upper classes in Asia, especially in China 

and Japan. International trade is dominated by the 

Chinese, whose preference for sea cucumber stems 

from its high nutritional content and health-giving 

properties. Traditional knowledge on sea cucumber as 

medicine exists; for example, the Cuvierian tubules 

used as crude plaster for minor wounds. Extracts 

183 

TRADER/EXPORTER 

FORWARDER/ 

SHIPPER 

Classifying 

Pre-Collection Collection Delivery Receiving Processing Storing Delivery Receiving 

/Packing 

Storing Shipping 

Preparation of: 

• banca 

• food 

• other fishing 

implements 

COST 

(PhP/kg) 

BUYING 

PRICE 

PhP/kg) 

SELLING 

PRICE 

PhP/kg) 

NET 

INCOME 

PhP/kg) 

TIME 

(days) 

• Travel to 

fishing site 

• Fin-fishing/ 

Sea 


collection 

• Travel back 

to fish 

landing site 

DIVER/COLLECTOR 

• Bring 

collected 

sea 


to 

assembler 

for 

processing 

• Count the 

number of 


cucumbers 

• Pay 

gatherer per 

piece of sea 


collected 

• Gutting at the 

mouth 

• Parboiling 

• Mixing with 

papaya leaves 

• Boiling with 

salt 

• Brushing to 

remove outer 

layer 

• Smoking 

• Packaging 

in plastic 

• Transport to 

trader, 

buying 

station, or 

exporter 

• Weigh the sea 


• Further dry 



that are not 

yet stone-dry 

• Sort sea 


according to 

species 

• Sort 

according 

to size 

• Pack in 

sacks lined 

with plastic 

cellophane 

or as 

required by 

clients 

15 21 9 

285 

300 4,200 

300 4,200 5,364 

1,179 1,155 

0.3 6 15 

PROCESSOR 

TRADER/EXPORTER 

• Secure minimum 

volume of sea 

cucumbers for 

shipment 

• Process required 

permits 

• Pay necessary 

transport/customs 

fees 

FORWARDER/ 

SHIPPER 

Classifying 

Pre-Collection Collection Delivery Receiving Processing Storing Delivery Receiving /Packing Storing Shipping 

CONSTRAINTS 

• Declining volume 

• High fuel cost 

• Ban on compressor 

• Increasingly smaller 

sizes 

OPPORTUNITIES 

• Increasing price due to 

increasing demand 

• Increasing number of 

alternative uses 

• Possibility of searanching/culture 


• Poor processing/product quality 

• Inadequate capital 

• Slow turn-over time 






• Poor quality 

• Increasingly smaller sizes 





EXPORT 

MARKET 

• Hong Kong 

• Singapore 

• China Mainland 

• Korea 

• Taiwan 

• Japan 

• etc. 

EXPORT 

MARKET 

from the muscular body are used for tumours, fungal 

infections, high blood pressure, arthritis and muscular 

disorders (Trinidad-Roa 1987). 

Hong Kong is still the major world market, followed 

by Singapore. However, Hong Kong generally 

re-exports products to mainland China. The product 

type, volume and value of global trade in sea cucumber 

are shown Table 4. World trade for sea cucumber 

continues to increase as the price for the product 

increases over time, with the Chinese population 

remaining the major consumers.

Table 4. Global trade in sea cucumber 

PRODUCT FORM YEAR 

2005 2006 2007 

Live, fresh, chilled 

Volume (million t) 56 34 67 

Value (US$‘000) 

Dried, salted in brine 

375 392 424 

Volume (million t) 6,463 4,883 5,734 

Value (US$‘000) 


46,342 42,021 55,852 

One notable characteristic of the Hong Kong market 

is the proliferation of herbs and medicine stores, 

which sell sea cucumber displayed in large glass jars 

(Figures 4, 5). A number of high-value tropical species 

can be found in these stores, including H. scabra, 

H. fuscogilva, Thelenota ananas, H. whitmaei and 

Actinopyga lecanora. Prices vary considerably from 

HK$1,200 to HK$1,500/kg, with reported sales of 

6–7 kg/day. 

In general, the Hong Kong market can be characterised 

as having: 

• a high preference for particular species. 

Apostichopus japonicus is the most popular species 

Figure 4. Herb and medicine store in Hong Kong 

184 

(also called meihua or wuxing), and is sold for up 

to HK$8,000 per 600 g in the herb and medicine 

stores. Holothuria scabra, H. fuscogilva, T. ananas 

and H. whitmaei are also highly valued 

• an apparent preference for product origin, with 

the general indication that all the sea cucumber 

being sold in the stores are from Japan, hardly 

acknowledging the huge importation of produce 

from South-East Asia 

• a distinct preference for product quality and size, 

resulting in a wide price range, even within a 

single species (Table 5).

Figure 5. Sea cucumbers on display in a herb and medicine store, Hong Kong 

Price-related marketing system 


As mentioned, price behaviour provides a snapshot 

of the overall industry status. Two important characteristics 

of the sea cucumber marketing system 

that can be discerned based on price behaviour are 

stability and viability. Unlike most other agricultural 

or fishery product prices, which exhibit high seasonal 

variability, the price of sea cucumber has been stable 

for the past 5 years. This is remarkable considering 

that sea cucumber collection is somewhat seasonal. 

However, the product can be stored for very long 

periods when properly dried, which probably smooths 

out the seasonality effect. 

Sea cucumber is still considered a minor commodity 

in official commodity statistics of countries 

in South-East Asia, and reliable time-series data on 

price by country are not available. In addition, prices 

vary by species, size and quality. Time series of average 

price data (i.e. average of the various species) 

would therefore have practically no analytical value. 

Price behaviour over time can be assessed only for 

the same species belonging to the same size and 

quality classification. 

185 

A useful set of data on sea cucumber prices covering 

the price range of several species traded in the 

Philippines during 2000–07 is provided by Labe 

(2009). For most commercially exploited species, 

the buying price (i.e. received by fishers) was three 

to four times higher in 2007 than in 2000. This 

phenomenal increase in sea cucumber price has 

been identified as the primary factor that induced 

overfishing, especially of the high-value species, 

in many countries. However, it is also possible that 

the increase in price was due to overfishing itself, as 

this would cause the supply curve to shift upward 

with increasing fishing effort (fishing cost) per unit 

catch. The sea cucumber industry appears to have 

been caught in a vicious cycle of high price leading 

to overfishing, which, in turn, leads to decrease 

in stock and total catch (supply), pushing the price 

even higher, and the cycle starts again. The depletion 

of wild sea cucumber stock may have the effect 

of low-value species becoming medium value, and 

medium-value species becoming high value, until 

many of the species have become depleted (Pe 2009). 

Such high prices reflect the lucrative nature of sea 

cucumber production and trade. More importantly, 

high prices almost warrant the profitability of 

expanded production through aquaculture.

Table 5. Range of retail prices for dominant sea 

cucumber species in South-East Asia 

Sea cucumber species Value range 

(US$) 

Stichopus hermanni 62.50 

Stichopus chloronotus 21.25–65.00 

Holothuria (Microthele) nobilis 20.00–78.95 

Bohadschia argus 20.00–30.00 

Apostichopus japonicus 17.50–112.50 

Holothuria fuscogilva 15.50–95.00 

Thelenota ananas 12.50–67.50 

Holothuria scabra 9.00–112.50 

Actinopyga lecanora 8.00–71.25 

Actinopyga miliaris 8.00-–44.00 

Holothuria edulis 8.00–22.50 

Stichopus variegatus 6.75–62.50 

Actinopyga mauritiana 5.00–15.00 

Holothuria sp. 4.75–44.00 

Actinopyga echinites 4.50–57.50 

Thelenota anax 3.68–60.00 

Holothuria rigida 3.00–59.00 

Holothuria impatiens 2.50 

Holothuria atra 1.75–22.50 

Pearsonothuria graeffei 1.75–5.00 

Bohadschia marmorata 1.40–23.75 

Source: SEAFDEC (2009) 

Marketing opportunities for 

expanding production 

The current state of sea cucumber fisheries completely 

discounts any possibility of expanding production 

through increased collection from the wild. The 

resource is already overfished in South-East Asia. 

Regulating harvest and other conservation measures 

are being contemplated in various countries to encourage 

stock recovery. Obviously, aquaculture is the only 

means to expand production of sea cucumber in the 

region. The technical viability of hatchery, nursery 

and grow-out (pond, pen and sea ranches) has already 

been established for certain species such as H. scabra. 

186 

The financial viability of H. scabra culture seems very 

positive considering its high value. However, there 

are marketing opportunities and challenges associated 

with expanded production, and these must be 

clearly understood if South-East Asian countries are 

to benefit fully from aquaculture programs. 

The demand for sea cucumber is the most important 

opportunity for expanded production. Consumers 

use sea cucumber not only as food, but also as medicine. 

Demand will probably be limited to Chinese 

consumers, at least in the near future; however, considering 

the increasing global trend towards health 

foods and alternative medicines, its popularity with 

other ethnic groups may increase. 

Even assuming that demand will be limited 

to Chinese markets, the future of sea cucumber 

trade remains vibrant. China is the fastest growing 

economy in the world, with increasing gross 

domestic product, per-capita income and population 

growth—one in every five people in the world is 

Chinese. The distribution system for sea cucumber 

is well established in China, with numerous herb 

and medicine stores ensuring that consumer access 

to these products is very high. Another marketing 

opportunity is the increasing Chinese population in 

almost all countries in the world. Import demand 

from other countries can be expected to rise as 

Chinese residents increase. 

The sea cucumber trade is well established in 

South-East Asia. In each country, local traders are 

present to move the product from fishers to exporters 

or city-based buyers. Additional volume from 

expanded production through aquaculture can easily 

be absorbed by existing market chains. Exporters are 

the key players in the sea cucumber trade, since most 

countries in South-East Asia export the product and 

only a small amount is consumed locally. However, 

the transaction cost involved in the export business is 

high, as coastal villages are widely dispersed. In the 

Philippines, exporters have to establish buying stations 

in many parts of the country or engage the services of 

procurement agents to be able to secure bigger volume. 

One opportunity that may be explored is direct 

market linkage between the sea cucumber farmers and 

exporters. Unlike collection from the wild, where daily 

volume is small and geographically dispersed, production 

from aquaculture comes in larger volumes from 

identified locations during predetermined periods. 

This could lower the search cost, and even transport 

and other costs normally incurred by exporters, and 

may entice them to transact directly with producers.

Marketing challenges 

While market prospects are generally bright, there 

are a number of challenges that have to be addressed 

if countries in South-East Asia are to benefit fully 

from expanded sea cucumber production due to 

aquaculture. The absence of reliable market and trade 

information is a huge challenge. Updated price data, 

which could serve as the basis for formulating sound 

production and marketing decisions, do not exist. In 

the Philippines, information asymmetry persists— 

certain market players have greater access to information, 

giving them undue advantage, especially in 

price bargaining. Distribution systems become multilayered, 

since those who have the latest information 

(especially on prices) can embark on pure arbitrage. 

While there are cases where product moves only 

along three layers (collector→processor→exporter), 

there are also instances where the product moves 

along two or three additional layers involving local 

traders and commission agents. These appear redundant 

and contribute to marketing inefficiency rather 

than adding real value to the product. 

Another important challenge relates to primary 

processing, the single most important determinant of 

product quality and one for which the market pays a 

very high price. Primary processing methods currently 

in use are highly variable; no standard protocol is being 

followed, resulting in highly variable product quality. 

The methods employed are very traditional, without 

knowledge and consideration of existing standards 

for processed food products (e.g. GMP and HACCP). 

A large processing firm in Vietnam that employs 

global standards has ceased to include sea cucumber 

in its product lines, since the volume of raw material 

(i.e. fresh sea cucumber) was too small for the 

firm to achieve economies of scale. This problem is 

perhaps true for other South-East Asian countries. 

As mentioned, sea cucumber collection is widely 

dispersed, and the volume from individual locations 

is small. Village-level processing, primarily carried 

out through traditional methods, will likely remain 

as a distinct feature of the industry in the region. 

Whether expanded production through aquaculture 

can change this is uncertain. Supply from aquaculture 

should be large enough and available on a continuous 

basis to encourage large processing firms to engage 

in processing the product. 

The absence of officially formulated and wellimplemented 

grades and standards for sea cucumber is 

another challenge. This is crucial since such measures 

187 

could guide transactions along the value chain. 

Fishers and village-level processors may not find the 

incentive to improve primary processing if they know 

that exporters would end up classifying good-quality 

product as lower grade based on arbitrary standards 

developed by the exporters themselves. 

Finally, the structure of the sea cucumber market 

may be characterised as oligopsonistic (i.e. a market 

condition in which there are few buyers), resulting in 

market inefficiencies exacerbated by lack of adequate 

information along the chain. 

Recommendations 

South-East Asia is a major source of sea cucumber 

supplied to the world market. However, the fishery is 

mostly artisanal, carried out by low-income households. 

Sea cucumber is generally an incidental catch 

in finfish fishing, although fishery activities where 

it is targeted are becoming more significant. Given 

declining catch from the wild, a number of possibilities 

can be explored to meet the ever-increasing 

demand. For example: 

• promoting aquaculture involving technically established 

protocols that can be explored to address 

demand and supply gaps 

• expanding research to develop culture protocols 

for other high-value species 

• improving support for efforts designed to generate 

new products from sea cucumber 

• exploring new export destinations, especially in 

countries with significant Chinese populations 

• establishing direct market linkage between producers 

and exporters to reduce market inefficiencies 

• establishing regularly updated statistics and information 

systems for sea cucumber 

• formulating and implementing official grades and 

standards 

• improving village-level small-scale primary 

processing 

• exploring strategies that could lead to the achievement 

of economies of scale in large-scale modern 

processing methods/facilities that observe international 

standards for processed food products. 

References 

Brown E., Perez M., Garces R., Ragaza R., Bassig R. and 

Zaragoza E. 2010. Value chain analysis for sea cucumber 

in the Philippines. WorldFish Center: Penang, Malaysia.

Gamboa R., Gomez A. and Nievales M. 2007. The status of 

sea cucumber fishery and mariculture in the Philippines. 

University of the Philippines in Mindanao: Davao City, 

Philippines. 

Ibrahim K. 2009. Sea cucumber utilization and trade in 

Malaysia. Pp.41–62 in ‘Report of the regional study 

on sea cucumber fisheries, utilization and trade in 

Southeast Asia 2007–2008’. Southeast Asian Fisheries 

Development Center: Bangkok, Thailand. 

Labe L. 2009. Sea cucumber utilization and trade in the 

Philippines. Pp. 68–94 in ‘Report of the regional study 




Macfadyen G, Ediriweer A.H.S., Perer U.L.K., Rajapakshe 

R.P.S.P., Amaralal K.H.M.L. and Mahipala M. 2009. 

Value chain analysis of beche de mer in Sri Lanka. 

GCP/SRL/054/CAN project report. Funded by Canadian 

International Development Agency and executed by Food 

and Agriculture Organization of the United Nations. 

Pe M. 2009. Sea cucumber utilization and trade in 

Myanmar. Pp. 63–67 in ‘Report of the regional study 




188 

Purcell S.W. 2010. Managing sea cucumber fisheries with 

an ecosystem approach. Edited/compiled by A. Lovatelli, 

A. M. Vasconcellos and Y. Yimin. FAO Fisheries and 

Aquaculture Technical Paper 520. Food and Agriculture 


SEAFDEC 2009. Report of the regional study on sea 

cucumber fisheries, utilization and trade in Southeast 

Asia 2007–2008. Southeast Asian Fisheries Development 

Center: Bangkok, Thailand. 

Sereywath P. 2009. Sea cucumber utilization and trade in 

Cambodia. Pp. 26–29 in ‘Report of the regional study 






1987, 15–17. 

Wiadnyana N. 2009. Sea cucumber utilization and trade in 

Indonesia. Pp. 30–40 in ‘Report of the regional study 



Development Center: Bangkok, Thailand.

Understanding the sea cucumber 

(beche-de-mer) value chain 

in Fiji and Tonga 

Theo A. Simos 1* 

Abstract 

As reported in other Pacific island communities and many countries around the world, wild stocks of sea 

cucumber in Fiji and Tonga are declining because of unsustainable levels of fishing. The Pacific Agribusiness 

Research for Development Initiative (PARDI) is a partnership involving the Secretariat of Pacific Community, 

the University of the South Pacific and a consortium of Australian universities, funded by the Australian 

Centre for International Agricultural Research. PARDI seeks to create sustainable livelihoods by identifying 

constraints to economic development in the Pacific islands region, and by developing appropriate technologies 

or products to resolve these constraints. It is currently evaluating the sea cucumber industry and its 

contribution to community livelihoods in Tonga and Fiji. This paper presents preliminary literature search 

findings of the PARDI study into sea cucumber market chains in these two Pacific island countries. Although 

an initial literature review revealed a scarcity of reliable information, interim maps of the current supply 

chains of both Fiji and Tonga have been developed and are discussed here. Research outcomes may lead to 

improvements in processing, value-adding to beche-de-mer and identification of new niche markets, and 

may facilitate investment in sea ranching and aquaculture. 

Introduction 

Sea cucumber is a valuable resource for income generation 

for many remote coastal dwellers in Fiji and 

Tonga, but the fisheries have exhibited boom–bust 

cycles since the early 1800s (Kinch et al. 2008). 

Fresh harvested sea cucumbers undergo a series of 

cooking and drying processes to produce a dried, 

shelf-stable product (beche-de-mer) that can be 

shipped in ambient dry conditions to markets in 

Asia, where it is highly prized by Chinese consumers 

(Ferdouse 2004). There are many species exploited, 

with some commanding high prices, but there is 

significant variability in quality and grade of bechede-mer 

(Choo 2008; Kinch et al. 2008). 

1 Adelaide University / ACIAR / Pacific Agribusiness 

Research for Development Initiative (PARDI), Adelaide, 

South Australia 


189 

As reported in other Pacific island communities 

and many countries around the world, wild stocks of 

sea cucumber in Fiji and Tonga are declining because 

of unsustainable levels of fishing (Kinch et al. 2008). 

Consequently, sea cucumber (particularly sandfish, 

Holothuria scabra) is becoming a priority group for 

development in the aquaculture plans of a number of 

countries, although, in reality, more development is 

needed before it can become a commercially viable 

alternative. 

A new development initiative related to sea 

cucumber has been funded by the Australian 

Centre for International Agricultural Research 

(ACIAR): the Pacific Agribusiness Research for 

Development Initiative (PARDI). The partnership 

includes the Secretariat of the Pacific Community 

(SPC); the University of the South Pacific (USP); 

a consortium of Australian universities, including 

the Adelaide University Value Chain group, James 

Cook University and researchers from Southern

Cross University; as well as industry representatives 

and government agencies in selected Pacific island 

countries (PICs). 

PARDI seeks to create sustainable livelihoods by 

identifying constraints to economic development in 

the Pacific islands region, and undertaking research 

to develop appropriate technologies or products to 

resolve these constraints. Therefore, it is currently 

evaluating the sea cucumber industry and its contribution 

to community livelihoods in Tonga and Fiji. 

This paper presents preliminary literature search 

findings of the PARDI study into the sea cucumber 

market chains in these two PICs. 

Methodology 

In order to identify potential constraints to the sea 

cucumber industry in Fiji and Tonga, PARDI has 

adopted the following approach: 

1. Review research and literature that have been 

undertaken in the Asia–Pacific region to identify 

gaps in our understanding of the whole value 

chain. 

2. Analyse and map the existing value chain from 

harvesting → processing → export → distribution 

→ consumption. 

3. Identify key partners and stakeholders (public 

and private) willing to co-invest and contribute 

to the research process, and who are also willing 

to participate in implementing change and 

improvements. 

4. Conduct research into constraints that limit the 

ability of these market chains to be more market 

responsive, equitable and, ultimately, more 

sustainable. 


Literature review 

An examination of existing literature (currently 

in progress) has highlighted significant gaps in 

knowledge about the current status and long-term 

sustainability of the beche-de-mer value chains in 

both Fiji and Tonga. It indicates that there is a lack 

of coordination between participants dependent on 

financial returns from fishing, processing and export, 

and that the issue of overfishing will need to be 

addressed by participants. There are also some issues 

relating to the impacts of harvesting and processing 

methods (Ram 2008). 

190 

Industry structure 

There are a large number of operational steps and 

participants involved in the industry, particularly 

once the beche-de-mer is exported. PARDI investigations 

have identified some key knowledge gaps in 

both the supply and demand sides of the industry in 

both countries, and a picture of the flow of value in 

transactions from fishing to consumption is emerging. 

Interim maps identifying key components of the 

current supply chains in both Fiji and Tonga have 

been developed (Figures 1, 2). 

While there are purported to be up to 19 buyers 

and processors listed in Fiji, the industry appears to 

be consolidating, and a number of operators have 

left the industry. The estimated harvest volume and 

value presented here is based on data provided by Fiji 

Fisheries (FITIB 2009). In Tonga, sea cucumber harvest 

volume and value are estimated from Fisheries 

Department data. However, the economic returns and 

importance to the three island regions participating 

in this industry require further substantiation. The 

amount of sea cucumber collected live (fresh:dried 

= 12:1) (Skewes et al. 2004; Purcell et al. 2009) has 

been used to estimate beche-de-mer export volumes 

across all species; however, drying conversion 

ratios vary between species and may require further 

validation. 

Preliminary estimates indicate that the value of the 

raw commodity when consumed by restaurant patrons 

in China and other markets in Asia is increased in 

value many times. Further research interviewing 

participants in target markets will be undertaken. 

Chain orientation 

Both Fiji and Tonga beche-de-mer industries are 

very much ‘supply driven’, where fishers, processors 

and exporters push product down to the next part of 

the chain. There are no industry development plans, 

and the literature search found little evidence of collaboration 

or flow of information between the fishing 

community, processors, exporters, customers and 

consumers of beche-de-mer in international markets. 

Flow of value and information 

Well-processed and dried beche-de-mer is an 

internationally traded commodity in high demand, 

but the flow of commercial value (cash income) 

from value-adding and marketing is tightly held by a 

few operators, and value returns to fishers from the 

resource are limited. Remote communities, whose

HARVESTING BUYING AND DRYING 

18+ species 

collected live 

FIJI ISLAND 

Volume distribution 

REGIONS 

Northern region 

Vanua Levu 

1,800 tonnes 

Central region 

Vitu Levu 

760 tonnes 

Southern region 

Lau Group 

680 tonnes 

Western region 

Mamanuca/Yasawa 

Group 

360 tonnes 

ESTIMATES 

Harvest value = US$6 m 

Harvest volume = 3,600 t 

19+ processing drying 

and trading companies 

operating in central and 

northern regions 

Buyers / 

Processors 

Agents 

Processors / 

Exporters 

Exporters 

ESTIMATES 

Export value = US$9 m 

Export volume = 300 t 

EXPORT TRADING MARKET CHANNELS 

Figure 1. Proposed Fiji beche-de-mer value-chain map based on information gathered by PARDI to date, 

and supply-chain information from Brown et al. (2010) 

HARVESTING BUYING AND DRYING 

20+ species 

harvested 

TONGA 

Volume distribution 

ISLAND REGIONS 

Nuas Group 

40 tonnes 

Vava`u Group 

960 tonnes 

Ha`apai Group 

800 tonnes 

Tongatapu 

400 tonnes 

ESTIMATES 

Harvest value = US$6 m 

Harvest volume = 4,000 t 

1 Licence 

Holder 

Processor 

8 Licensees 

Processors / 

Exporters 

8 Licensees 

Processors / 

Exporters 

8 Licensees 

Processors / 

Exporters 

ESTIMATES 

Export value = 

US$9.5 m 

Transport 95% sea freight, 

5% airfreight 

Figure 2. Proposed Tonga beche-de-mer value-chain map based on information gathered by PARDI to 

date, and supply-chain information from Brown et al. (2010) 

191 

Hong Kong 

Singapore 

SE Asia 

USA / 

Canada 

Taiwan 

Korea 

ESTIMATES 

Import value = 

US$11.25 m 

Principal consumption market 

Mainland China 

Importers 

Agents 

Wholesalers 

Retailers 

Grading 

Transportation 

Reconstitution 

Distribution 

Restaurants 

EXPORT TRADING MARKET CHANNELS 

Transport 80% sea freight, 

20% airfreight 

Hong Kong 

Singapore 

SE Asia 

USA / 

Canada 

Taiwan 

Korea 

ESTIMATES 

Import value 

US$12 m 

Principal consumption market 

Mainland China 

Importers 

Agents 

Wholesalers 

Retailers 

Grading 

Transportation 

Reconstitution 

Distribution 

Restaurants 

C O N S U M E R S 

Consumer value 

unknown 

C O N S U M E R S 

Consumer value 

unknown

livelihoods depend on the harvesting and processing 

of sea cucumber, have little understanding of export 

customer and consumer requirements, and are at the 

mercy of local middlemen and traders. 

Beche-de-mer is generally not consumed locally 

but exported, mainly to destinations with large 

Chinese populations (Akamine 2009). However, 

the lack of publicly available knowledge around the 

structure of the distribution channels in Asia makes 

it difficult to collect information that will encourage 

changes to practices, and improvements in returns 

to participating communities. There was no public 

information available about assessing the economic 

impact of the decline in the wild resource, and it is 

difficult to determine what livelihood returns are 

generated to flow back to communities. 

Processing and export 

From the supply side, researchers have identified 

that there is some waste of the resource that occurs 

during the harvesting and processing stages of bechede-mer 

(Ram et al. 2008). Production losses, due to 

undersized product, low-value species, postharvest 

damage and poor processing, may require intervention 

if deemed significant. PARDI has commissioned 

a new scoping study (to commence in 2011) on processing 

improvements, which will attempt to address 

these issues. 

In Fiji, some processors have raised concerns 

about the viability of the industry as catches decline, 

and they fear that declining stocks in Tonga may lead 

to a flood of new traders setting up new harvesting 

and processing arrangements in what is already a 

diminishing resource. Fiji and Tonga fisheries agencies 

have a history of regulating the exploitation of 

the fishery (Adams 1993). 

There are many markets around the world that 

import beche-de-mer, particularly in Asia (Choo 

2008). Little is known about the structure and role 

of agents, processors, licensees and exporters in these 

markets. Export volumes, species, quality and grades, 

sizes and value (Figures 1, 2) are estimated, and it 

is unclear which destination markets are exploited 

when, why and by whom? The market that has the 

most influence is mainland China, which traditionally 

has used Hong Kong (duty free entrepôt) to access 

sea cucumber and other dried marine products from 

all parts of the world. These markets are principally 

located in the southern province of Guangzhou, with 

product traded to many markets throughout China. 

The growing affluence and opening up of China is 

192 

changing these trading patterns, and may provide 

opportunities to identify new market channels and 

consumer segments. 

Markets and consumers 

No reliable information on beche-de-mer exists 

that identifies the current structure and performance 

of market channels and participants in the export 

trade. Further research is required to identify data 

collected on the volume, value and destination of 

product exported from Tonga and Fiji. The preliminary 

value-chain maps (Figures 1, 2) describe 

the elements of each market chain. These are based 

on beche-de-mer research from Asia and the trading 

structures of other commodities exported to these 

markets (Brown et al. 2010). 

Consequently, little baseline information about 

wholesale and retail market channels, and the purchase 

behaviour and consumption of beche-de-mer 

by consumers, can be presented. Potential improvements 

in returns based on innovative product packaging 

or other specifications are therefore difficult 

to estimate. However, there is an expectation that, 

with growing expansion of the economy, the demand 

for beche-de-mer among Chinese consumers will 

continue to grow in both volume and value terms 

in the future. 

Once beche-de-mer is exported from the Pacific 

region, it undergoes many changes in handling, and 

passes through many destinations before it ends up in 

a restaurant on a plate. Further grading and reconstitution 

is undertaken and, in some cases, the product 

is sold in forms other than for food consumption. 

The product’s uses are diverse, and the value of the 

resource in these applications may need to be further 

understood. 

The lack of information on consumer preferences 

for the end product means that there are very few 

options for resource owners to exploit. 

Recommendations for further 

research 

In order to better understand the value chain and 

complete its mapping, the following research is 

recommended: 

1. conducting a supply-side study to understand the 

collection and harvesting of sea cucumber at the 

village scale 

2. conducting a supply-side study to understand the 

economic value and the income to communities,

and to develop ‘what-if’ scenarios where new 

options of restructuring the processing distribution 

and marketing can be evaluated 

3. investigating the collection, purchasing, valueadding 

and processing industry status. Operators 

in the sea cucumber industry need to be involved, 

and their role and contribution towards the future 

of the industry better defined 

4. conducting a demand-side study on market 

research to identify and understand current 

market destinations, channels, channel players, 

tax structures, pricing and profit margins 

5. investigating the demand-side of the export 

industry as it currently operates, including export 

destinations, market values, desirable species 

and grades, and packaging. These insights may 

help to establish clearer product knowledge, and 

enable better industry development plans to be 

initiated 

6. conducting consumer research in key markets 

(e.g. China, Hong Kong, Singapore) to better 

understand purchasing and consumption 

behaviour, perceived product benefits, and the 

many ways the product is presented, prepared 

and consumed. Consumer insights can then be 

used to improve existing product and packaging 

standards, and food safety and product 

handling procedures. Aspects such as place of 

origin, nutritional aspects, ethical marketing 

and sustainable environmental practices can be 

leveraged for the development of superior marketing 

and selling campaigns. New niche-market 

channels may be identified in markets willing to 

pay more for elaborately processed or partially 

processed products, packaged and labelled in 

non-traditional ways that can be unique and 

highly differentiated 

7. reviewing new technologies to match consumer 

requirements (new processing, preservation, 

packaging, transportation–distribution channels, 

and buying techniques) for the development of 

products that are unique and that capture product 

benefits. 

Other research topics that would be useful include: 

1. developing new models to enable fishers and key 

stakeholders to work together, create value-driven 

organisational structures and develop new market 

niches 

2. facilitating customs, finance and treasury agencies 

in developing new policy settings for investment 

attraction 

193 

3. collecting, analysing and disseminating industry 

data that can be used to develop sustainable 

industry plans. 

Conclusions 

Further analysis in unlocking the true state and 

economic benefits of the beche-de-mer value chains 

in Fiji and Tonga will be important in determining 

appropriate future interventions. PARDI will seek to 

engage fishing communities, processors, exporters 

and other industry stakeholders. They can play an 

important role in identifying ways to draw the attention 

of different stakeholders to opportunities for 

improvement at different stages in the value chain. 

Research outcomes may lead to improvements in 

processing, value-adding to beche-de-mer and identification 

of new niche markets, and may facilitate 

investment in sea ranching and aquaculture. 

References 

Adams T. 1993. Management of beche-de-mer fisheries. 


Akamine J. 2009. Challenging ‘boom and bust’ market pressures: 

development of self-managed sea cucumber conservation 

in Rishiri Island, Hokkaido, Japan. Biosphere 

Conservation: for Nature, Wildlife, and Humans 9(2), 

1–12. 

Brown E.O., Perez M.L., Garces L.R., Ragaza R.J., Bassig 

R.A. and Zaragoza E.C. 2010. Value chain analysis for 

sea cucumber in the Philippines. WorldFish Center: 

Penang, Malaysia. 

Choo P.S. 2008. Population status, fisheries and trade of sea 

cucumbers in Asia. In ‘Sea cucumbers: a global review of 

fisheries and trade’, ed. by V. Toral-Granda, A. Lovatelli 

and M. Vasconcellos. FAO Fisheries and Aquaculture 



Ferdouse F. 2004. World markets and trade flows of sea 

cucumber / beche-de-mer. In ‘Advances in sea cucumber 

aquaculture and management’, ed. by A. Lovatelli, 

C. Conand, S. Purcell, S. Uthicke, J.-F. Hamel and 

A. Mercier. FAO Fisheries Technical Paper No. 463, 



FITIB (Fiji Islands Trade and Investment Bureau) 2009. 

Fiji islands investment opportunities in the sea cucumber 

industry. FITIB: Suva, Fiji Islands. 

Kinch J., Purcell S., Uthicke S. and Friedman K. 2008. 

Population status, fisheries and trade of sea cucumbers in 

the Western Central Pacific. In ‘Sea cucumbers a global 


A. Lovatelli and M. Vasconcellos. FAO Fisheries and



Purcell S.W., Gossuin H. and Agudo N.S. 2009. Changes in 

weight and length of sea cucumbers during conversion to 

processed beche-de-mer: filling gaps for some exploited 

tropical species. SPC Beche-de-mer Information Bulletin 

29, 3–6. 

Ram R. 2008. Impacts of harvest and post-harvest processing 

methods on the quality and value of beche-de-mer in 

Fiji islands. Masters thesis, Division of Marine Studies, 

School of Islands and Oceans, Faculty of Science, 

Technology and Environment, University of the South 

Pacific. 

194 

Ram R., Friedman K. and Sobey M. 2008. Impacts of 

harvesting and post-harvesting processing methods on 

the quality and value of beche-de-mer in Fiji Islands. The 

11th Pacific Science Inter-Congress in conjunction with 

the 2nd Symposium of French Research in the Pacific, 

Tahiti. 

Skewes T., Dennis D., Donovan A., Ellis N., Smith L. and 

Rawlinson N. 2004. Conversion ratios for commercial 

beche-de-mer species in Torres Strait. Torres Strait 

Research Program. AFMA Project Number: R02/1195. 

Australian Fisheries Management Authority and CSIRO.

Processing cultured tropical 

sea cucumbers into export product: 

issues and opportunities 

Steven W. Purcell 1* and Nguyen D.Q. Duy 2 

Abstract 

Sea cucumbers cultured in ponds or in the sea are potentially lucrative commodities, but their export value can 

be gained or lost through the processing used. The gutting, water temperature, cooking times, handling and 

drying techniques should all be carefully controlled in order to achieve the highest grade possible for export. 

Farmed sea cucumbers may have thinner body walls than wild animals, but have the advantage of being of 

consistent size, can be processed immediately after being removed from the water, and can be processed in 

bulk. Processors must understand the preferences of overseas importers, as desired processing approaches 

may vary. The use of fuel for boiling sea cucumber to make beche-de-mer can be an ecological concern. Body 

organs and muscle bands may offer new products for value-adding of cultured sea cucumbers. Likewise, 

markets are more open to fresh and canned product. Training and providing guides in the best methodologies 

and new market opportunities to processors present fruitful scope for improving the cost-effectiveness of 

farming and sea ranching tropical sea cucumbers. 

1 National Marine Science Centre, Southern Cross 

University, Coffs Harbour NSW, Australia 


2 Research Institute for Aquaculture, Nha Trang, Khanh 

Hoa province, Vietnam 

195

Sandfish (Holothuria scabra) farming 

in a social–ecological context: 

conclusions from Zanzibar 

Hampus Eriksson 1* 

Abstract 

Sandfish (Holothuria scabra) farming is being promoted as a potential economic activity for coastal communities, 

and especially for those currently involved in fishing for sea cucumbers—an unsustainable fishery. 

With the collapse of many tropical sea cucumber stocks, and with agendas to find new income alternatives for 

coastal populations, the interest in aquaculture, particularly in sandfish, will most probably increase. However, 

in-depth analysis of the social and ecological consequences from introduction of sandfish farming is lacking. 

In Zanzibar, Tanzania, 74 sea cucumber fishers were asked if they would like to farm sea cucumbers. About 

64% of the respondents were positive to farming. Their comments highlighted that they perceived farming 

as an addition, not a replacement, to catch from the fishery, and that they were concerned about the personal 

risks involved in an investment. The responses illustrate that aquaculture may have a negligible or negative 

effect on the fishery. There are also potential ecological impacts, which, of course, will depend on the scale 

of the activity, but for which there is currently little knowledge. The risk-awareness poses the question on 

what business model a sandfish enterprise should operate to reduce risk for communities with few income 

alternatives. The results from the interviews indicate that it is essential to learn from past sandfish farming 

initiatives and other aquaculture ventures that have resulted in the development of standards. It is also apparent 

that it is important to apply a social–ecological systems approach to sandfish farming development. 

Introduction 

Many sea cucumber fisheries around the world are suffering 

from overfishing (Purcell 2010). This can generally 

be attributed to insufficient capacity to manage the 

fishery (Muthiga et al. 2010), lack of ecological knowledge 

from which to form management (Uthicke et al. 

2004), stochastic recruitment (Uthicke et al. 2009), 

strong market demand (Anderson et al. 2011), illegal 

fishing (Price et al. 2010) and limited presence 

of institutions (Eriksson et al. 2010). While local 

fisheries are becoming depleted, resulting in moratoriums 

being placed on exports in numerous locations 

(Purcell 2010), there is still a need to maintain income 

1 Department of Systems Ecology, Stockholm University, 

Stockholm, Sweden 


196 

opportunities in communities and nations. In this context, 

tropical sea cucumber aquaculture is currently 

gaining momentum. 

The only suitable tropical sea cucumber varieties 

for farming, using hatchery-produced animals, are 

those in the sandfish species complex (Agudo 2006; 

SPC 2009). There is currently some uncertainty 

regarding species nomenclature across the Indo– 

Pacific region, where the taxon Holothuria scabra 

may contain varieties in need of species recognition 

(Massin et al. 2009). This text will therefore use the 

common name ‘sandfish’. Sandfish is a high-value 

species in strong demand on the international market, 

which makes it a promising candidate for aquaculture. 

Properties indicating its suitability for farming 

are, for example, that it feeds low in the food chain 

and occurs naturally in dense populations in many 

tropical coastal waters (Hamel et al. 2001).

A number of scenarios exist for sandfish aquaculture. 

Commonly, emphasis is on farming hatcheryproduced 

animals in enclosures or no-take zones, 

with the aims of rebuilding depleted stocks and 

enhancing livelihoods for coastal communities in 

areas with few income alternatives. The potential of 

aquaculture as a source of income in coastal communities 

is illustrated by the prospective suitability of 

sea ranching, or farming hatchery-produced animals 

in pens in coastal waters (Bell et al. 2008; Robinson 

and Pascal 2009), in particular where there is a need 

to reduce effort in the fishery to prevent stock demise 

and maintain income opportunities. 

Fishers from poorer households are less likely to 

exit a declining fishery (Cinner et al. 2008), emphasising 

both how poverty traps communities in declining 

fisheries, and how important is the generation 

of income opportunities to support communities to 

reduce fishing effort. In addition, subsistence or artisanal 

fishers often support themselves from a diverse 

range of livelihoods (Allison and Ellis 2001), which 

raises a paradoxical question of whether profits from 

sandfish aquaculture will replace those of fishing, or 

if it will be perceived as an addition to fishing, with 

fishing effort continuing at similar levels. Subsistence 

or artisanal fishers are also generally exposed to high 

degrees of risk and uncertainty in terms of personal 

safety and income (Andersson and Ngazi 1998). 

This can prompt an increased emphasis on a cooperative 

behaviour to reduce risks, but, in a poverty 

situation, also reluctance to engage in activities that 

might further increase risk (Barrett et al. 2006). 

In Madagascar, where community-based sandfish 

farming from hatchery-produced animals has been 

introduced, sandfish juveniles are bought by families 

on credit and sold when harvestable (Robinson and 

Pascal 2009). Risk is thus to some extent borne by 

families. This risk raises concern with regard to how 

farming should operate to minimise risk in poor 

households. 

Zanzibar Island, in the western Indian Ocean, has 

an active fishery targeting sea cucumbers for export 

as beche-de-mer (Figure 1). The fishery in Zanzibar 

is institutionally marginalised, lacking management 

and control; as a result, easy-access stocks are widely 

depleted, and exports are maintained with the aid of 

sequential exploitation and trade (Eriksson et al. 

2010). In this study, information collected through 

interviewing fishers participating in the sea cucumber 

fishery in Zanzibar was used to explore how 

they perceive the potential activity of farming sea 

197 

cucumbers. The fishers had not been exposed to sea 

cucumber aquaculture previously, and no hatcheries 

were operating in Zanzibar. The results were analysed 

in the context of how farming would fit into a coastal 

setting where the fishery is active and income alternatives 

are few. The focus of the analysis was the 

potential effect on the sea cucumber fishery, and the 

potential risks involved for communities. 

Methods 

As part of a study to map and assess the local sea 

cucumber fishery in Zanzibar, fishers were interviewed 

regarding their perceptions of the fishery 

and its management (Eriksson et al. 2010). Here, 

answers from the categorised yes-or-no question, 

‘Are you interested to farm sea cucumbers’, and 

the open-ended follow-up question, ‘If so, why/why 

not’, were used to analyse perceptions and attitudes. 

Interviews were conducted in eight villages (Nungwi, 

Mkokotoni, Uroa, Chwaka, Mazizini, Fumba, Unguja 

Ukuu and Mtende) (Figure 2), which were chosen 

because they had an active sea cucumber fishery. The 

interviewees were chosen randomly, and included 

men and women gleaning in nearshore areas, and 

men that breath-hold and scuba dive in nearshore and 

offshore areas. The interviews were semi-structured 

(Denscombe 1998) and conducted in Swahili with the 

assistance of a translator. 

Results 

Seventy-four fishers (51 men and 23 women) were 

interviewed. There was interest to farm sea cucumbers 

among both men and women; however, men 

showed a higher interest than women (69% and 52% 

positive answers, respectively) (Figure 3). 

Almost one-third of the interviewed fishers indicated 

that they perceived farming as an addition to 

catch from the fishery, rather than a replacement 

(Table 1). For example, fishing was highlighted as 

a continuous activity while having to wait for harvest. 

Some fishers also expressed concerns about 

the personal risks involved in a farming enterprise, 

and one fisher highlighted that this could be avoided 

through employment. The perceptions of risk were 

illustrated by, for example, an emphasis on the current 

lack of knowledge, the weak management of the 

sea cucumber fishery in Zanzibar and the likelihood 

of catch being stolen. Ten percent of interviewees 

highlighted their reluctance due to the risk of animals

A 

B 

Figure 1. A: Middleman gutting and boiling recently caught curryfish in Mkokotoni village, 

Zanzibar. B: ‘Pentard’ teatfish product held in hand over brown sandfish products at an 

exporter’s location in Stone Town, Zanzibar 

198

Tanzania 

Kenya 

Mozambique 

Western Indian Ocean 

20 km 

Mkokotoni 

Nungwi 

ZANZIBAR 

(Unguja Is.) 

Mazizini 

Fumba 

Chwaka 

Uroa 

Unguja Ukuu 

Mtende 

Figure 2. Map of Zanzibar (Unguja Island) showing 

locations of villages where interviews with 

fishers were conducted 

Table 1. Perceptions of sea cucumber farming among 

interviewed fishers in Zanzibar, Tanzania 

Issue Comment/concern 

Effect on fishery ‘I can still fish while I farm’ 

‘Can develop more catch’ 

‘Too long to wait for harvest’ 

‘More to sell’ / ‘More income’ 

Risk for 

communities 

‘Some could steal’ 

‘Need training on how to do it’ 

‘Cannot afford to wait for harvest’ 

‘Only if employed’ 

being poached. In relation to knowledge, four fishers 

(female) said they had no interest because they 

did not know how to do it, while three fishers (men) 

indicated an interest if taught how to farm. One fisher 

highlighted that it might be an activity for the whole 

village to get involved in. 

N 

199 

No. of responses 

50 

40 

30 

20 

10 

0 

Men 

n = 51 

Figure 3. Distribution of answers among men and 

women in Zanzibar, Tanzania, regarding 

their interest in farming sea cucumbers 

Discussion 

Yes 

No 

69% 31% 52% 48% 

Women 

n = 23 

Effect on fishery 

The responses by sea cucumber fishers in this 

study illustrate that there is an interest to farm sea 

cucumber, but that it cannot be taken for granted that 

farming will reduce fishing pressure or improve the 

health of wild stocks. In many developing countries, 

a diversified palette of livelihoods (e.g. fishing, farming, 

trading or casual work) is common (Allison and 

Ellis 2001), arguing that it is unlikely that aquaculture 

will replace any one fishing activity; rather, 

it will diversify alternatives, thereby providing a 

potentially important source of social resilience. 

Whether it will alleviate fishing pressure on other 

marine resources, however, is a complex question. 

As experienced in seaweed farming, aquaculture can 

have a negligible effect, or even a negative effect, on 

use of other marine resources, for example through 

increased capital required for fishery improvement 

(Sievanen et al. 2005). In Zanzibar, a majority of 

both fishers and trade middlemen make it clear 

that they want access to more capital to invest in 

the fishery (Eriksson et al. 2010), and it is therefore 

probable that profits from farming may be used for 

investing in the already depleted fishery. To what 

extent this scenario can be generalised is difficult 

to gauge. However, in most tropical sea cucumber 

fisheries, it is likely that fishing will continue or 

increase as long as the trade is profitable and the 

governance weak.

There are also potential ecological systems effects 

with sandfish farming that have not been properly 

evaluated or studied. Seaweed farming, which was 

introduced into Zanzibar during the 1990s, is today 

widespread, and may perhaps provide some reference 

for sandfish farming. It is also a low-intensive 

(i.e. does not require additional nutrient input) 

cash crop, grown in the same coastal communities 

where sea cucumbers are fished, and serves the 

international market. When seaweed farming was 

introduced, it was endorsed with minimal environmental 

concerns. Today, however, ecological studies 

have shown that it reduces the abundance of seagrass 

and macrofauna (Eklöf et al. 2005), reduces aboveground 

biomass up to 40% (Eklöf et al. 2006), and 

alters community structure (Bergman et al. 2001). 

These effects obviously depend on the scale of 

the activity. It is likely that sandfish farming will 

have ecological effects not yet studied, which may 

compromise ecosystem integrity (e.g. translocation 

of broodstock) or deteriorate ecological goods and 

services already providing subsistence to coastal 

communities. Therefore, it is equally important to set 

aside resources for studying the ecological systems 

effects of farming as it is to technically develop the 

hatchery and marketing aspects. 

Risk for communities 

Although a majority of fishers that were 

interviewed showed an interest in farming, some 

were reluctant to engage in the activity due to the 

perceived financial risk and lack of knowledge. 

This raises the issue of which business model an 

enterprise should operate under. In Zanzibar, use 

of coastal marine resources is characterised by 

cooperative and conflicting institutions that both 

cushion and exaggerate resource-use conflicts and 

sustainability (de la Torre-Castro and Lindström 

2010). This can be attributed to many similar fishing 

situations elsewhere, and highlights the institutional 

complexity that often affects resource use and ability 

to implement management. The risks of farming 

will therefore be dependent on the context in which 

it is introduced, highlighting the importance of a 

proper feasibility study before initiation. There are 

no universal blueprints. 

Fishers in Zanzibar also expressed concerns 

about the risk of poaching, a problem experienced 

in Madagascar (Robinson and Pascal 2009). This 

highlights a governance issue that is difficult to 

circumvent, but certainly compromises the activity 

200 

and constitutes risk for investors. In Madagascar, 

some communities that bought subsidised juveniles 

for grow-out in 2008 are still in debt from lost stock 

(G. Robinson, pers. comm.). This was obviously 

not the objective for any of the participants in this 

operation, but it pinpoints that the full production 

chain is not foolproof, and that there are monetary 

risks involved. In addition to risks of crop losses, it 

is costly to operate a hatchery, and profits are ‘far 

from certain’ (Hair et al. 2011). Some interviewed 

fishers consequently indicated that they would prefer 

employment, limiting their personal investment to 

labour. That women are being exploited for profits, 

as evidenced by an astounding discrepancy in catch 

value between fishing men and women (i.e. approximately 

US$2.40/kg versus US$0.10/kg paid to men 

and women, respectively, for similar catch (Eriksson 

et al. 2010)), is probably the reason why they are 

more reluctant to engage in farming than men are. 

This situation illustrates that fishing communities 

are already vulnerable and not resilient to cope with 

change. If the ambition is to create independence and 

economic opportunities for fishing communities, risk 

in farming enterprises should consequently not be 

borne at the community level. 

Outlook 

The reasons for sea cucumber overfishing and 

stock degradation are complex. In some cases, 

however, weak governance and absence of capacity 

to implement control appears to be a central problem 

(Muthiga et al. 2010; Eriksson et al. 2010). In 

this context it is important to underscore that new 

technology cannot replace governance, nor can it 

produce the same number of species (sometimes 

reaching 35) that are targeted in the fishery (Purcell 

2010). Successful introduction of hatchery enterprises 

to restock depleted populations or alleviate 

pressure from fishing is therefore not guaranteed 

with the current level of knowledge, and the level 

of management participation in fisheries where 

governance is weak. That expectations from sandfish 

aquaculture need to be balanced was illustrated 

in a brief questionnaire sent out to five scientists 

with leading insight and experience in the topic of 

sandfish farming, asking them to rank on a 1–5 scale 

how likely some considerations are to be realised 

(Eriksson 2009). The highest scoring concern 

was that farming would be introduced on inflated 

promises. This is very unfortunate—not living up 

to unreasonable initial expectations may undermine

the future potential success of sandfish farming. 

Moreover, it may lead communities into taking 

unnecessary risks. 

The future of sandfish farming lies in understanding 

and managing the fishery and beche-de-mer trade 

(e.g. Friedman et al. 2008), and in the critical evaluation 

of experiences and development of research 

in relation to successes and failures of farming; for 

example, filling the knowledge gap regarding business 

models that benefit fishers and communities. 

Therefore, it is very important to share knowledge 

and experience so that successes are replicated and 

mistakes not repeated. In this sense, developing new, 

or strengthening existing institutions, requires that 

learning mechanisms are implemented, and that a 

social–ecological systems perspective is applied. This 

whole process would be made easier by adopting a 

benchmark approach to developing standards for 

responsible sandfish farming, on which managers 

and political decision-makers can base decisions, as 

has been done for other aquaculture organisms (e.g. 

WWF 2010). 

Conclusion 

There is an interest among communities to farm sea 

cucumbers. However, the current fishery situation in 

Zanzibar is a result of weak governance, in that actors 

in the trade operate with minimal ambition to allow 

fishers to capture profits, and this raises questions 

regarding the feasibility of farming. The lack of 

governance mechanisms that would allow for a sustainable 

and functioning fishery cannot be substituted 

with new technology (hatcheries). Therefore, unless 

governance issues are addressed and improved, it is 

very likely that a farming enterprise will go down 

the same road as the fishery—impoverished and with 

marginal social equity. 


Thanks foremost to fishers that participated in this 

study, and also to Maricela de la Torre-Castro, Nils 

Kautsky, Max Troell, Narriman Jiddawi, Caroline 

Raymond, Hanna Nilsson, Chantal Conand, Maria 

Byrne and Kim Friedman for support. This work 

was funded by the Western Indian Ocean Marine 

Science Association Marine and Coastal Science 

for Management (WIOMSA/MASMA) regional sea 

cucumber project, and by the Swedish International 

Development Agency (SIDA). 

201 

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2010. Resource degradation of the sea cucumber fishery 

in Zanzibar, Tanzania: a need for management reform. 

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Friedman K., Purcell S., Bell J. and Hair C. 2008. Sea 

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World sea cucumber markets: Hong Kong, 

Guangzhou and New York 

Jun Akamine 1* 

Abstract 

Hong Kong, Guangzhou and New York are the most important markets in the sea cucumber industry. Dried 

sea cucumbers are brought from all over the world to be bought and sold in Hong Kong. Traders and 

whole salers are located along Nam Pak Hong Street in the Sheung Wan area in the north-west of Hong Kong 

Island. Hong Kong and Guangzhou in Guangdong province, China, have been tightly connected since the 

birth of Hong Kong in the 19th century. Through this channel, most of the dried marine products imported 

into Hong Kong are re-exported to Guangdong, from where they are traded throughout China. Wholesalers 

gather along Yat Tak Lou (Yi De Lu) Street in Guangzhou. This paper will explore the historical development 

of the sea cucumber market in China, with special reference to regional differences. A recent development 

in the New York market is also explained in relation to trade of the Galapagos sea cucumber, Isostichopus 

fuscus. The characteristics of these three intertwined markets indicate that resource management plans should 

take market preference into consideration. 

Trade in dried sea cucumber 

In 2007 Hong Kong imported 5,296 tonnes (t) of 

dried sea cucumber: Papua New Guinea exported 

the most to Hong Kong (704 t of dried sea cucumber), 

Indonesia (653 t) second, and Japan (585 t) 

third. According to the Monthly Statistics of Hong 

Kong, it re-exported 4,149 t of dried sea cucumber 

to 13 countries and regions in 2007. Among them, 

China imported 3,576 t (86% of the total re-export 

volume from Hong Kong). 

Sea cucumber species 

About 50 species out of a total of 1,200 are currently 

commercially traded in the world. Sea cucumber can 

be classified by its form in two categories: ci-shen 

(‘spiky’) and guang-shen (‘shiny). The spikes actually 

refer to the parapodia on a sea cucumber’s back 

and sides that harden when dried. 

1 Nagoya City University, Mizuho-ku, Japan 


203 

The most common ci-shen species is Stichopus 

japonicus, which can be found in the Bohai Sea and 

along the Korean, Japanese and Russian maritime 

coasts. The species shows regional variation in 

sharpness of its spikes, with the Hokkaido variety 

demonstrating the sharpest spikes. Several of the 

internationally traded ci-shen sea cucumber species 

have temperate seas as their natural habitat, while 

guang-shen sea cucumbers, the rest of the commercially 

traded species, are typically found in tropical 

marine environments. Some types of tropical sea 

cucumber found in the Pacific Ocean and around 

South-East Asia, such as Thelenota ananas and 

Stichopus chloronotus, are also classified as ci-shen. 

Isostichopus fuscus, a species harvested around the 

Galapagos Islands and in other locations, is also 

considered ci-shen. 

The differences in the form of sea cucumber 

species also play an important role in sea cucumber 

food preparation. Chinese cooking is largely divided 

into Beijing, Shanghai, Sichuan and Cantonese cuisine, 

and regional differences are most pronounced 

between Beijing and Cantonese cuisine. Traditionally,

in Beijing cuisine, ci-shen sea cucumbers are preferred, 

while the Cantonese prefer guang-shen species. 

While geographic location plays a part in the 

preference for the temperate S. japonicus in the north 

and the tropical Holothuria fuscogilva or H. scabra in 

the south, cooking styles also explain the difference. 

Pekinese prefer to serve food in small dishes, while 

the Cantonese use a large serving dish placed in the 

centre of a round table, which explains the higher 

demand for small ci-shen species in Pekinese, and 

large guang-shen species in Cantonese, cuisine. 

204 

Conclusion 

To my understanding, the New York market prefers 

ci-shen, especially I. fuscus. The species began to 

be commercially harvested in the late 1980s, and 

became very particular in symbolising globalisation 

of the sea cucumber industry, as well as sea 

cucumber conservation (e.g. the Convention on 

International Trade in Endangered Species of Wild 

Fauna and Flora). This paper presumes that the New 

York market would have played an important role 

in the exploitation of I. fuscus in Central and South 

American countries such as Mexico and Ecuador. 

This is another reason why it is necessary to investigate 

market preference, and feed the results back into 

resource management planning.

Applying economic decision tools to improve 

management and profitability of sandfish 

industries in the Asia–Pacific region 

Bill L. Johnston 1 

Abstract 

A component of the recent Australian Centre for International and Agricultural Research-funded sandfish 

project in the Philippines, Vietnam and Australia has been to build and refine economic decision tools for 

both sea ranching and pond-based culture of sandfish. Presented here is the background to these models and 

some basic theory required to understand model outputs. Models take a discounted cash flow approach to 

predicting returns over a given life cycle. Output includes the expected annual returns when the farm is paid 

off, and the maximum interest rate at which funds can be borrowed to invest in the project. A risk module 

allows the user to incorporate anticipated risk to return from a range of sources. Access to these models is 

open, and a web address is provided. 

Introduction 

Sea cucumber farming presents a novel economic 

proposition as it differs in a number of ways from 

other aquaculture ventures. When compared with 

more traditional culture systems, sea ranching presents 

a unique set of parameters regarding survival, 

transport and release issues; social and management 

issues; and exposure to natural system variability. 

Similarly, pond-based farming differs markedly from 

culture of other species, most notably in the absence 

of feeding costs, which is offset in part by low stocking 

densities. Developing tools based on empirical 

experience gained through pilot-scale sea ranching 

and pond-culture projects provides a valuable tool to 

enable potential industry entrants to assess viability 

under their particular circumstances. 

Economic decision tools are a conceptual framework 

that allows users to make informed decisions 

1 Department of Employment, Economic Development 

and Innovation, Maroochy Research Station, Nambour, 

Queensland, Australia 


205 

underpinned by sound economic methodology. In 

this project, cost–benefit analysis was used as the 

conceptual framework for the economic evaluation 

of sandfish production. The customised economic 

tools (industry- or situation-specific) aim to assist 

producers and potential investors understand the 

economic requirements, costs and benefits, and risks 

involved in production. 

More specifically, economic decision tools allow 

producers to assess impacts such as disease, climate 

and market prices (known as externalities) that may 

influence profitability. They can also assess changes 

in profitability caused by changes in the cost of 

feed, labour, electricity, packaging and transport. 

Additionally, the decision tools can evaluate the economic 

effects of improvement in yield, future development 

plans or a change in production efficiency. 

Without rigorous economic decision frameworks, 

the resulting actions can be based on unsound, 

incomplete or misleading information. Equipping 

clients with decision tools provides improved capacity 

for increased profitability and sound economic 

development, and reduces the risk of failure.

Developing an effective, sustainable and profitable 

aquaculture enterprise requires a lot of time and 

capital input. Prevailing market conditions make it 

very important to thoroughly research and identify 

markets for products before venturing into production. 

This applies to almost all industries, particularly 

aquaculture. Little or no information is available to 

farmers and interested investors about the establishment 

costs or the profitability of operating many 

currently existing sandfish enterprises. By making 

an economic analysis tool available for farmers, we 

aim to provide the knowledge and information necessary 

so that they are fully prepared and understand 

the capital required, operating costs involved, labour 

input and profit margins they might expect to receive 

given an identified level of risk (e.g. the likelihood of 

losses by cyclones, or fluctuations in market price). 

Culture or sea ranching of sandfish is a relatively 

new income-generating activity (compared with traditional 

wild harvest) now being practised in a range 

of countries as an alternative to other income sources. 

Many people are interested in moving toward more 

sustainable methods of sandfish production, but do 

not have enough information to decide whether they 

are worth doing. They need a way of comparing these 

new activities with the other, more-familiar activities. 

The income, expenditure and investment levels for 

any business will be different from place to place. 

Once an economic decision tool framework has 

been developed for each income-generating activity, 

it can be distributed relatively easily (electronically) 

for rural development trainers or extension agents to 

use with people in an interactive way. Working with 

farmers to develop data inputs for models relevant 

to their particular situation will allow comparisons 

and decisions to be made regarding different incomegenerating 

activities. 

Project objectives 

The economic tools discussed here were developed 

or modified as a component of the current 


Research (ACIAR) – WorldFish Center project in 

the Philippines, Vietnam and Australia. The broad 

economic objectives of the project include: 

• diversified livelihoods based on sea ranching of 

sandfish 

• improved livelihood resilience for small-scale 

pond farmers due to diversification 

• increased earnings for fishers from 

206 

– restored stocks of sandfish 

– production of A-grade beche-de-mer through 

increased size limits and improved processing 

methods. 

The tools discussed are specifically targeted at providing 

potential industry participants with a window 

into the economic realities of this type of enterprise. 

The primary focus has been to look at the possibility 

of sandfish culture and sea-ranching operations as 

alternatives to more traditional pursuits. Aquaculture 

enterprises are usually capital intensive, requiring 

substantial investment with extended payback periods. 

The ability of these enterprises to source investment, 

establish capital infrastructure and weather 

financial and operating expenses during inception 

has, in the past, been a major stumbling block for 

sustainable aquaculture industries. Variability in market 

prices and income flows also poses major hazards 

to establishing early profits and ensuring viability in 

the long term. 

The objectives of the modelling component of the 

project were to: 

1. develop three focused economic decision tools, 

based upon cost–benefit analysis, that people 

can use to assess the viability of the proposed 

sandfish enterprise, as follows 

• hatchery–nursery 

• pond-based production 

• sea-ranching production 

2. consult with people who are experts in these 

income-generating activities, and obtain the 

necessary information to develop representative 

business frameworks for each enterprise 

3. apply and interpret risk analysis profiles for the 

associated enterprises. 

Explanation of the models 

The economic models were developed using the 

Microsoft Excel spreadsheet program and based upon 

the cost–benefit analysis technique. Cost–benefit 

analysis is a conceptual framework for the economic 

evaluation of projects, with an aim to assist the user to 

make a decision regarding the allocation of resources. 

In particular, it helps the user to make decisions about 

whether or not to invest in an enterprise. 

Discounted cash-flow analysis was used to determine 

the annual cost structure and the likely profitability 

for each of the commodities. Discounting 

reduces future costs or benefits to an equivalent 

amount in today’s dollars. People generally prefer to

eceive a given amount of money now rather than the 

same amount in the future, because money has an 

opportunity cost. For example, if asked an amount 

of money they would prefer to receive in 12 months 

time in preference to $100 now, most people would 

nominate a figure around the $110 mark—to them, 

money has an opportunity cost of around 10%. A 

dollar tomorrow is not worth the same as a dollar 

today. Therefore, the timing and duration of these 

projects has an influence on the annualised costs and 

revenues of the project. The single amount calculated 

using the compound interest method is known as the 

‘present value’ (PV) of the future stream of costs and 

benefits. The rate used to calculate PV is known as 

the discount rate (opportunity cost of funds). 

All the models developed assume a project life of 

20 years, and use a real discount rate (equivalent to 

the current long-term bond rate, which is normally in 

the range 4–10%) to calculate the net present value 

(NPV). The budgets also incorporate the initial 

capital and establishment costs. 

Data input into the spreadsheet-based models 

is simple, and is guided by two simple rules—red 

colour denotes a calculation cell and yellow colour 

an input cell. Values (size of ponds, cost of labour 

etc.) can be entered into the yellow cells, while the 

values in the red cells are calculated from the data 

entered by the user. The summary statistics provide 

a breakdown of costs on a per unit basis. 

Once the data are entered into the model, the user 

can apply it to determine the impact of various management 

decisions. For example, the farmer may wish 

to know how a change in wages will affect his profit, 

or how introducing new management techniques will 

affect production. 

All the statistics are explained in the next section. 

The output includes the expected annual returns 

when the farm is paid off, and the maximum interest 

rate at which funds can be borrowed to invest in the 

project. Once an economic analysis has been done, 

this maximum interest rate figure should be taken 

into consideration when negotiating finance for a 

project. 

Definition of terms 

Net present value (NPV) and equivalent 

annual return 

The NPV is the difference between the present 

value of cash inflows and the present value of cash 

207 

outflows over the life of the project. If the NPV 

is positive, the project is likely to be profitable. 

When the NPV is converted to a yearly figure, it 

becomes annualised; in this report, it is called the 

equivalent annual return. It is a measure of equivalent 

annual returns generated over the life of the project 

expressed in today’s dollars. 

Discount rate 

The discount rate is the interest rate used in discounted 

cash-flow analysis to determine the present 

value of future cash flows. It takes into account the 

time value of money (the idea that money available 

now is worth more than the same amount of 

money available in the future because it could be 

earning interest), and the risk or uncertainty of 

anticipated future cash flows (which might be less 

than expected). 

Internal rate of return (IRR) 

The discount rate at which the project has an NPV 

of zero is called the internal rate of return (IRR). It 

represents the maximum rate of interest that could 

be paid on all capital invested in the project. In other 

words, if all funds were borrowed from a bank, and 

interest charged at the IRR, the borrower would 

break even; that is, recover the capital invested in the 

project at the end. 

Payback period 

A graph representing the cumulative cash flow 

is displayed in the models. The year in which the 

cash flow rises above zero is considered the payback 

period, and is a measure of the attractiveness of a 

project from the viewpoint of financial risk. Other 

things being equal, the project with the shortest 

payback period would be preferred. It is the period 

required for the cumulative NPV to become greater 

than zero, and remain greater than zero over the life 

of the project. 

Benefit:cost ratio 

The benefit:cost ratio (b:c) is simply a measure 

of the total flow of benefits over the life of the project 

compared with the flow of costs. If the ratio is 

greater than one, the project is deemed acceptable. 

In other words, the ratio describes the return per dollar 

invested; for example, if the b:c is 1.6, it can be 

said that, for every $1.00 invested in the project or 

enterprise a return of $1.60 is made.

Risk analysis 

Risk and uncertainty are features of most business 

and government activities, and need to be understood 

to ensure rational investment decisions are made. The 

process involves the following steps: 

1. defining the model—modelling the business 

operations 

2. defining the uncertain variables—price and yield 

3. assigning probability distributions for each of our 

uncertain variables—allocating probabilities to 

the categories of minimum, poor, average, good 

and maximum 

4. running the simulation and analysing the 

results—for this risk analysis, the results 

are displayed using a cumulative probability 

distribution. 

The best way to demonstrate how to input information 

for the risk analysis and interpret the results is 

with an example (Table 1). The user needs to first 

specify the likelihood of various risk factors (cyclone, 

theft etc.) affecting production (or yield). In Table 1, 

‘Risk factors’ are listed and then the probability of 

each of these is stated in the ‘Probability’ column, 

with reference to the description in the ‘Occurs’ 

column. 

As seen in Table 1, data are entered in the 

‘Probability’ column, resulting in the cumulative 

percentages shown in the ‘Cumulative’ column. The 

user then enters the expected production or yield (as 

Table 1. Expected risks for sandfish farm example 

208 

in Table 2). It is not necessary to enter the minimum 

or maximum probabilities, nor their associated 

production. 

This example table indicates that there is a: 

• 10% chance of producing 0–20,000 kg (minimum 

to poor) 

• 20% chance of producing 20,000–25,000 kg (poor 

to average) 

• 40% chance of producing 25,000–27,500 kg (average 

to good) 

• 30% chance of producing 27,500–30,000 kg (good 

to maximum) 

The same process is followed for the price risk, 

except that the minimum and maximum prices are 

entered by the user. The minimum price cannot be 

zero; it may be a subsidised price set by the government 

or a historical market low. 

Once all the data have been entered, the simulation 

is run. The simulation produces a set of results that 

is graphically shown as a cumulative probability 

distribution (Figure 1), indicating the entire range of 

outcomes possible, based on the user’s inputs, for the 

enterprise. 

The annual return is represented along the x-axis 

and the probabilities on the y-axis (Figure 1). In this 

example, with the costs and prices as specified in the 

input (yellow) cells, the cumulative probability curve 

crosses the $0 return point at approximately 0.2. This 

can be interpreted as meaning that a 20% chance 

exists of making an annual return of less than $0 

Expected 

production 

Risk factors Occurs Probability Cumulative 

Zero–poor Cyclone, severe disease and flood 1 in 10 years 0.1 (10%) 0.1 

Poor–average Theft, some disease, lack of stock 

supplies 

2 in 10 years 0.2 (20%) 0.3 

Average–good Good conditions, minimal disease, good 

feed 

4 in 10 years 0.4 (40%) 0.7 

Good–maximum Excellent growing conditions, no disease 3 in 10 years 0.3 (30%) 1.0 

Table 2. Risk input proforma for sandfish farm example 

Expected production Kilograms of sandfish Cumulative probability 

Minimum 0 0.00 

Poor 20,000 0.10 

Average 25,000 0.30 

Good 27,500 0.70 

Maximum 30,000 1.00

–$15,000 –$10,000 –$5,000 

1.00 

0.90 

0.80 

0.70 

0.60 

0.50 

0.40 

0.30 

0.20 

0.10 

0 

$0 

Annual return 

$5,000 $10,000 $15,000 $20,000 $25,000 

Cumulative probability 

Figure 1. Cumulative probability distribution for sandfish farm example 

(i.e. making a loss for the year). Alternatively, a line 

drawn vertically from the $10,000 mark on the horizontal 

axis meets the curve at about 0.8 (projecting 

across to the vertical axis), indicating that there is an 

80% chance of earning less than $10,000, and so on. 

Should business owners ‘pay’ 

themselves? 

While identifying costs for inclusion in the economic 

model framework, there is a tendency for users not to 

place any value on the time contributed by the owner 

of the business or the owner’s immediate family. 

Rather, this time and labour is treated as a non-valued 

good. It is generally assumed that the return to owner 

labour and management is realised only when the 

business generates sufficient profit. 

The fundamental problem with this way of thinking 

is that it distorts the decision to undertake that 

particular enterprise by underestimating the true cost 

of labour. If the business is able to generate sufficient 

revenues to compensate owner or family labour, plus 

all other operating (fixed and variable) and capital 

expenses, the enterprise would be deemed profitable. 

If the enterprise returns a profit based solely 

209 

on unpaid labour, the decision to undertake that 

enterprise would be based on false economies. 

There is a basic requirement to supply food and 

shelter (subsistence). If the enterprise selected does 

not meet this need, it should not be undertaken unless 

it provides a direct food supply to the family. 

Consideration must be given to the opportunity 

cost of labour. An economic value needs to be 

placed upon the time the business owner and his 

family devote to the enterprise, so that they can 

assess whether they are better off to be engaged in 

that business or in some other economic pursuit. 

Anybody using these economic models should estimate 

the cost of that labour, regardless of whether or 

not actual monies are to be drawn from the business 

to the owner or their family. 

Tool availability and access 

These tools have been developed as an open access 

utility, and are available for download from: . The tools continue to be 

refined based on updated empirical information, and 

new versions may be uploaded periodically.

Asia–Pacific tropical sea cucumber aquaculture - ACIAR

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