Gull-billed Tern (Gelochelidon nilotica)
Herring Gull (Larus argentatus)
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
CCLarge gull with deep chest, light grey back and heavy yellow bill with red spot (adult). Pinkish legs and black tipped primaries with white windows. Winter plumage with streaked head and neck. Develops grey mantle in 2.nd winter. Young birds may be difficult to distinguish from juvenile Greater- or Lesser Black-backed Gulls, and the species shows notable variation in both plumage and size. Juveniles generally shows darker head and less contrasting markings than Greater Black-back, and pale inner primaries (window), as opposed to the all black hand of young Lesser Black-backs.
Sound:Quite vocal. A long and strong "ay-kay-kay-kay-kay" with fading strength commonly heard. A deep "ga-ga-ga" heard from anxious birds. All calls much deeper pitched than Common Gull. Difficult to distinguish from Lesser Black-backed Gull, but tone is less nasal.
Contact call and song:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC