Gaviotín Embridado/Bridled Tern/Onychoprion anaethetus

Nombre en español: Gaviotín Embridado

Nombre en inglés: Bridled Tern

Nombre científico: Onychoprion anaethetus

Familia: Laridae

Canto: Simon Elliot

El charrán embridado (Onychoprion anaethetus) es una especie de ave marina Charadriiformes de la familia de los estérnidos, perteneciente al género Onychoprion.

Subespecies

Onychoprion anaethetus anaethetus
Onychoprion anaethetus antarctica
Onychoprion anaethetus fuligula
Onychoprion anaethetus melanoptera
Onychoprion anaethetus nelsoni
Onychoprion anaethetus recognita
Onychoprion anaethetus rogersi

Localización

Es una especie de ave que se encuentra en México, el Caribe, el oeste de África, península Arabiga, sudeste de Asia y Oceanía y oeste de Europa.

Bridled tern

The bridled tern (Onychoprion anaethetus) 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, (but not as pale as the grey-backed) 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 IOC:

O. a. melanopterus – (Swainson, 1837): Caribbean and West Africa.
O. a. antarcticus – (Lesson, 1831): Red Sea, Persian Gulf and western Indian Ocean.
O. a. anaethetus – (Scopoli, 1786): eastern Indian, and Pacific Oceans.
O. a. nelsoni – (Ridgway, 1919): west coast of Mexico and Central America.

Breeding

This species breeds in colonies on rocky islands. It nests in a ground scrape or hole and lays one egg. It feeds by plunge-diving for fish in marine environments, but will also pick from the surface like the black tern and the gull-billed tern. It usually dives directly, and not from the «stepped-hover» favoured by the Arctic tern. The offering of fish by the male to the female is part of the courtship display.