Scientific name: Chlidonias niger (Linnaeus, 1758)
Bird group: Gulls and Terns
Field characters. 24 cm. The only tern with completely dark breeding plumage, except for conspicuous white undertail and light underwings. Back and wings slate grey. Juvenile and adult in winter with white forehead, neck and underparts; a black shoulder patch distinguishes this species from White-winged Black Tern. Strongly flecked and spotted when in moult. Bill black, legs red-brown. Flies to and fro over water to pick up insects but rarely dives into the water. Nests in small colonies on water plants in shallow waters of marshes and lagoons; sometimes in soggy meadows.
Voice. Rather silent. Usually "kit" or a fairly shrill "creeck".
Distribution. Summer visitor. Rare colony breeder; decreasing in number.
Habitat. Breeds in marshes with floating plants, on which it builds its nest. On migration and in winter found on lakes and along coasts.
Food. During breeding season predominantly insects and other invertebrates; in winter also fish.