Tern sea terns have light grey or white body plumage as adults, with a black cap to the head. The legs and bill are various combinations of red, orange, yellow, or black depending on species. The pale plumage is conspicuous from a distance at sea, and may attract other birds to a good feeding area for these fish-eating species. When seen against the sky, the white underparts also help to hide the hunting bird from its intended prey. The Inca tern has mainly dark plumage, and three species that mainly eat insects, the black tern, white-winged tern, and black-bellied tern, have
Chinese crested tern Chinese crested tern The Chinese crested tern ("Thalasseus bernsteini") is a tern in the family Laridae, closely related to the Sandwich tern, "T. sandvicensis", and the lesser crested tern, "T. bengalensis". It is most similar to the former, differing only in the bill pattern, which is the reverse of the Sandwich tern's, being yellow with a black tip. From the lesser crested tern, which it overlaps in wintering distribution, it can be told by the white rump and paler grey mantle, as well as the black tip to the bill, which seen from up close also has a white point.