Appearance:

Breeding adult easily identified by white tail/rump combined with jet black under wing coverts and silvery upper wing. Immature with brownish back contrasting with pale, silvery upper wings and pale rump. Broad white collar, and lacks dark breast patch of immature Black Tern. Adult winter most liable to confusion with other terns, but upperparts much paler than Black Tern. Contrasting dark outer primaries and secondaries to rest of wing. Often retains some black under coverts even in winter which is diagnostic if seen. Slightly more compact than Black Tern and often recalls Little gull in shape. Bill noticeably shorter and thinner than in Whiskered Tern.

Sound:

Mostly silent away from breeding ground. Most diagnostic call a dry, rolling "krrrrrr-ta-ta" where the rolling is followed by one or two accentuated syllables, or just simply "krrrrrr". Used in excitement.

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:Marco Dragonetti, Licence,Link.

CC-photo:Dick Hoek, Licence,Link.

CC-photo:Lars Buckx, Licence,Link.

Appearance:

Adults in summer at close range unmistakable. Bill in juveniles almost black, and much less deep than in adults. Adults in winter plumage also show much darker bill and cheeks than in summer. At a distance head gives an all dark impression, with characteristic dark "shadow " in front of the eye. Head and bill less elongated than in other auks. Wings rounded with dark undersides. "Thighs" dark. Flight fluttering and energic, with shifting weight and angle.

Sound:

Deep, but not so coarse as Razorbill. Smoother and more gliding changes in pitch, like a "slow-motion" laugh or distant chainsaw; "aaaahrrr, aahr, ahr arh".

Contact call:

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

Featherbase

CC

CC-photo:zanzamos, Licence,Link.

Sounds:Recorded by Hans Petter Kristoffersen,http://www.xeno-canto.org ,CC license