White-winged Tern

The white-winged tern, or white-winged black tern, is a small marsh tern. Summer adults have short red legs, a short, stubby black bill, a black head, neck and belly, a very dark grey back, a white rump and an almost white tail, and wings that are mainly white, as the name says. In non-breeding plumage most of the black is replaced by white or pale grey, but a good deal of black remains on the underwing coverts, and the head shows a blackish, white-flecked crown and a dark patch in front of the eye (Wikipedia, general species account).

It breeds on freshwater marshes from south-eastern Europe to Central Asia and the Russian Far East, nesting on floating vegetation or on the ground close to water and laying two to four eggs in a nest of reed stems and plants. It migrates to Africa, southern Asia and Australia for the winter and is generally found in or near fresh water (Wikipedia, general species account).