Great Crested Tern

The greater crested tern, also called the crested, swift or great crested tern, nests in dense colonies on coastlines and islands in the tropical and subtropical Old World, from South Africa round the Indian Ocean to the central Pacific and Australia. Notable features include dark grey upperparts, white underparts, a yellow bill and a shaggy black crest that recedes in winter. Its darker battleship-grey upperparts, white forehead in full breeding plumage and greenish-yellow bill separate it from close relatives (Wikipedia, general species account). (Wikipedia, general species account).

It follows fishing boats for discarded bycatch and uses unusual nest sites such as roofs and artificial islands. Its four or five subspecies breed in the area from South Africa around the Indian Ocean to the central Pacific and Australia, all populations dispersing widely from the breeding range after nesting. Its young have a distinctive appearance, with strongly patterned grey, brown and white plumage, and rely on their parents for food for several months after they have fledged. (Wikipedia, general species account).