Red-Tailed Tropicbird

The red-tailed tropicbird is a seabird native to tropical parts of the Indian and Pacific Oceans, one of three closely related tropicbirds, described by Pieter Boddaert in 1783. Superficially it resembles a tern, with almost all-white plumage, a black mask and a red bill, and the sexes look alike. As the name says, adults have red tail streamers (Wikipedia, general species account).