Gull-billed Tern (Gelochelidon nilotica)
Iceland Gull (Larus glaucoides)
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
CCAll white wingtips like Glaucous Gull. Told apart from latter by rounded head, longer wings and shorter, more slender bill. Bill shorter than half the length of head, and lacks prominent hook. Primaries extends well past tail in sitting birds, and the whole rear of the bird seem slimmer. Eye bigger than in Glaucous Gull, with a more "gentle" expression. Comparison with nearby Herring Gulls fruitful. Iceland Gull often smaller than Herring Gull, and less heavy, while Glaucous Gull usually larger. Impression reinforced by Iceland's agile maneuvering.
Sound:Like Herring Gull, but tone sharper.
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