Grey-backed tern
The spectacled tern (Onychoprion lunatus ), also known as the grey-backed tern, is a seabird in the family Laridae.
A piscivore is a carnivorous animal that eats primarily fish. Piscivorous is equivalent to the Greek-derived word ichthyophagous. Fish were the die...
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TerrestrialTerrestrial animals are animals that live predominantly or entirely on land (e.g., cats, ants, snails), as compared with aquatic animals, which liv...
Oviparous animals are female animals that lay their eggs, with little or no other embryonic development within the mother. This is the reproductive...
Precocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. Precocial species are normall...
Soaring birds can maintain flight without wing flapping, using rising air currents. Many gliding birds are able to "lock" their extended wings by m...
Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, b...
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Partial MigrantPartial migration is when within a migratory species or even within a single population, some individuals migrate while others do not.
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starts withA close relative of the bridled and sooty terns (with which it is sometimes confused), the spectacled tern is less common than the other members of its genus and it has been studied less. The three species, along with the Aleutian tern were recently split into a new genus Onychoprion from Sterna (Bridge et al., 2005). They resemble the sooty tern but with a grey back instead of a black one. Their breast and underparts are white, and they have a black eye line from the bill to the back of the head.
The spectacled tern breeds on islands of the tropical Pacific Ocean. At the northern end of its distribution it nests in the Northwestern Hawaiian Islands (with the largest population being Lisianski Island) and two small islets off Oahu, in the east as far as the Tuamotu Islands, with other colonies in the Society Islands, the Line Islands, Phoenix Islands, Mariana Islands and American Samoa. There are unconfirmed reports of breeding as far south as Fiji, and as far east as Easter Island. Little is known about the populations outside of Hawaii. Outside of the breeding season the species is partly migratory, with birds from the Hawaiian Islands flying south. It is thought that birds in other parts of the Pacific are also migratory, and will disperse as far as Papua New Guinea, the Philippines, and Easter Island.