The black tern is a small member of the Laridae family at 9.5-10in (24-25.4cm) in length and 1.75-2 ounces (49.6-56.7g) in weight. It is identifiable in the breeding season by its jet black feathers on the head and body, the back fading to gray on the rump. The bill is nearly as long as the head and is bluish with a trace of dark red at the gape; the feet are also dark red. The upper wings and tail are uniformly gray, aside from white lesser wing coverts which form a small white shoulder when the bird is at rest. During the winter, black feathers fade to gray on the back and turn white on the underparts. Juvenile black terns are similar to the adult in winter plumage, but have barred wing coverts and are generally scalloped brown overall.