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:

Small head, short, thick neck, quite broad wings and fairly short tail. May be confused with a range of different species due to the highly variable plumage. Underparts range from almost white to very dark. Plumage tone ranges from chocolate to rusty brown. Dark morph usually with pale breast band. Shows 5 fingers like other Buteo, as opposed to small eagles. Tail lacks the broad terminal band of Rough-legged Buzzard. Neck thicker than in Honey Buzzard. Secondary coverts form a pale band in dark morph. Light morph typically with primary coverts forming black 'comma'. Soars with raised wings, but glides on straight wings.

Sound:

Quite vocal. Most typical call a wailing, mewing "peeoooo". Quite similar to Rough-legged Buzzard, but the pitch falls more rapidly and is then sustained for the last part of the call.

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:Piotr Szczypinski, Licence,Link.