Gull-billed Tern (Gelochelidon nilotica)
Black-headed Gull (Chroicocephalus ridibundus)
Easily confused with Sandwich Tern but choice of habitat usually different. Adults differs by noticeably shorter and deeper bill, lacking yellow tip. Wings are broader, tail is shorter and only slightly forked. Lacks crest. Primaries with dark trailing edge, especially underside. Rump pale grey, and there is no contrast between grey back and white tail as in Sandwich Tern. Loses the black cap in winter, but keeps a black mask (less black on head than Sandwich T). Immature birds also gives a paler impression. The back is almost uniform in colour, and the wings also have only diffuse markings. The dark trailing edge to the primaries is present though, together with dark eye mask. Rest of head is pale. Flight slightly front-heavy with shallow wing-beats. Catches insects in the air and from the ground in flight. Rarely plunge-dives. Prefers fresh water, and is often seen near wetlands, rivers and flooded fields, but also in salt water during migration.
Sound:Quite vocal and easily distinguished from most congeners. Mewing and sharp in tone, but not rattling or raucous like most terns. Most typical call is a disyllabic, mewing "ke-waat", with an upward inflection. Other variants are series of "ke-ke-ke-ke", or the mewing sounds.
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCChocolate-brown hood in adult plumage (seemingly black at a distance), but head only with dark markings in winter and juvenile plumages. Underparts of inner primaries dark grey. First few primaries white with black tip, both on upper side of wing and under. Last character conspicuous in all plumages, but slightly less obvious in juveniles due to larger dark area of wing-tip. Slender-billed Gull and Bonaparte's Gull show similar white first primaries, but differs in long and slender head profile and white underparts of hand respectively.
Sound:Quite vocal, especially at breeding ground. Distinct, harsh calls. A rasping "kreearr", and shorter, sharp warning calls; "kek".
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC