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:

Medium sized eagle with long, evenly broad wings and relatively short tail. Easily confused with Lesser Spotted Eagle, Clanga pomarina. Flight feathers usually paler than the dark coverts, and head and body same colour as wings. Only diffuse pale patch at base of primaries on upper wing (marked in C. pomarina). Pale base of primaries shows as "comma", but usually lacks pale base of under primary coverts, contrary to C. pomarina. Broader wings than C. pomarina, and the squarish wing-shape, short neck and tail recalls White-tailed Eagle (H. albicilla). U-shaped white patch at base of tail. Immature birds even darker than adults, and show white spots along upper wing coverts in two narrow bands. Very long "fingers" overall, and elongated 7th primary. Soars and glides on horizontal wings with drooping hand (as C. pomarina). Bill obviously heavier than C. pomarina, and yellow base and gular region stands out. Round nostrils.

Sound:

Vocal at breeding ground, and when courting. Short, barking, high-pitched whistles, not unlike a small dog. Slightly lower pitched than C. pomarina and with a fuller tone, but very similar.

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:David Farrow, Licence,Link.

CC-photo:Ronald Bontrop, Licence,Link.

CC-photo:Paul Schrijvershof, Licence,Link.

CC-photo:CharlesLam, Licence,Link.

CC-photo:Ronald Bontrop, Licence,Link.

CC-photo:Bart Moons, Licence,Link.