Appearance:

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

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

CC

CC-sound:Stanislas Wroza, Licence,Link.

Appearance:

Slightly smaller than Eider. Male at close range unmistakable. At a distance the black back is diagnostic. Female similar to female Eider, but feathering on bill is not reaching nostrils, giving the bird a peculiar "smile". Head shape is less triangular with a steeper forehead, and nail of bill is black. V-shaped barring on flanks.

Sound:

Male: Calls similar to Eider but easily distinguished by the vibrating quality. A "aaaooooooh" (shorter in duration than Eider) Starting on a low note, slowly ascending and ending on a descending note with a distinct vibrato/pulse. Often in the form of three calls: "oohh, a-ohhh hahahaoohohohoh". Usually accompanied by the female "ga ga ga ga".

Display-calls:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

CC

Sounds:Recorded by Andrew Spencer,http://www.xeno-canto.org ,CC license