Sterna anaethetus (GTM Research Reserve Bird Guide)

Sterna anaethetus

Onychoprion anaethetus

Summary ⁶

The Bridled Tern (Onychoprion anaethetus, formerly Sterna anaethetus - see Bridge et al., 2005) is a seabird of the tern family Sternidae. It is a bird of the tropical oceans.

General description ⁷

The specific name of the bridled tern, anathetus, is derived from the Greek for senseless or stupid, a reference to the ease with which hungry sailors captured this relatively docile seabird. Relative to other terns, the bridled tern is of average size, with a deeply-forked tail and long narrow wings. During the breeding season, the upperparts of its plumage, including the back, wings and tail, are brownish grey, while the underparts are generally whitish. The crown and nape are black but the forehead is marked by a triangular white patch that extends above and behind the eyes. The bill is about as long as the head and is black in colour, as are the legs and feet. Outside of the breeding season, the bridled tern is slightly paler, with its black crown streaked white and brown, and the dark feathers of the upperparts having white-tips, giving it a peppered appearance. Juveniles are similar in appearance to the adults but have a paler, streaked crown and upperparts heavily scaled with white and buff. Four to six subspecies, differing only slightly in appearance but occupying different parts of the bridled tern’s overall range, are variably recognised.