Gull-billed Tern (Gelochelidon nilotica)
Common Tern (Sterna hirundo)
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
CCDiffers from Arctic Tern in longer head, and more orangy red, rather than deep red, bill. Tip of bill usually black. Legs longer, but tail streamers shorter than AT. Underparts of primaries with diffusely bordered dark trailing edge (sharply bordered in Arctic Tern). Upper side of primaries with dark wedge (less apparent in winter). Secondaries opaque. Crest more apparent than in Arctic Tern and underside whiter. Juveniles with buff back.
Sound:Similar to Arctic Tern but deeper. Lacks latter's high pitched "tip-tip-tip" call, and the drawn out "kree-aaahh" call falls more distinctly in pitch.
Call:
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