Appearance:

Unmistakable in breeding plumage, but otherwise easily confused with other marsh terns. Breeding plumage with black head and belly, but pale underwing and grey rump. When in immature and winter plumage it differs from Common and Arctic tern by smaller size and short, moderately forked tail, and from other marsh terns by slimmer body and wings (compared to White-winged tern), and relatively long, thin bill. Both immature and adult winter show dark front edge of wing, and characteristic dark shoulder patch at wing base. Back is dark in immature birds. Grey rump in all plumages. Flight usually different from Sterna-terns, with erratic dives for no apparent reason, and "aimless" change of direction. Note that when foraging over saltwater, flight becomes more Sterna-like.

Sound:

Moderately vocal. Flight call a more or less clear "kleck, or a disyllabic "klee-ake" with accented first syllable. Sometimes slightly rolling "klirr-eke", but never as much as in White-winged Tern. Also a slightly harsher "kreek", but not as raspy as in Whiskered Tern.

Flight 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-sound:Ad Postma, Licence,Link.

Appearance:

Large and bulkily built diver with heavy bill, square head profile and steep forehead. Usually holds bill pointed straight, not uptilted like White-billed Diver. Summer: White underparts and chequered black back. Black bill and head. Neck with white band. Winter; white underparts and dark back. Neck with incomplete black band, creating contrasting, jagged edge. Heavy, goose-like flight.

Sound:

Song: Like a slow Black-throated Diver. Pitch slowly rising with a register break, progressing into a cyclic, two to four syllable, motif. Also various vibrating eerie descending calls. Often used as sound effect in horror movies.

Song:

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

CC-photo:jackanapes, Licence,Link.

CC-photo:jerryoldenettel, Licence,Link.

Sounds:Recorded by Patrick Åberg,http://www.xeno-canto.org ,CC license