Bridled tern
The bridled tern is a seabird of the family Laridae. It is a bird of the tropical oceans. The scientific name is from Ancient Greek. The genus comes from onux meaning "claw" or "nail", and prion, meaning "saw". The specific anaethetus means "senseless, stupid".
Description
This is a medium-sized tern, at 30–32 cm in length and with a 77–81 cm wingspan similar to the common tern in size, but more heavily built. The wings and deeply forked tail are long, and it has dark grey upperparts and white underparts. The forehead and eyebrows are white, as is a striking collar on the hindneck. It has black legs and bill. Juvenile bridled terns are scaly grey above and pale below.This species is unlikely to be confused with any tern apart from the similarly dark-backed sooty tern and the spectacled tern from the Tropical Pacific. It is paler-backed than that sooty, and has a narrower white forehead and a pale neck collar.
Distribution and movements
This bird is migratory and dispersive, wintering more widely through the tropical oceans. It has markedly marine habits compared to most terns. The Atlantic subspecies melanopterus breeds in Mexico, the Caribbean and west Africa; other races occur around the Arabian Peninsula and in Southeast Asia and Australasia, but the exact number of valid subspecies is disputed. It is a rare vagrant to western Europe.These are the four subspecies listed by the International [Ornithological Congress|IOC]:
- O. a. melanopterus – : Caribbean and West Africa.
- O. a. antarcticus – : Red Sea, Persian Gulf and western Indian Ocean.
- O. a. anaethetus – : eastern Indian, and Pacific Oceans.
- O. a. nelsoni – : west coast of Mexico and Central America.