Appearance:

Unmistakable. Dark green (appears black at a distance) above and white below. Wings also dark above and white below, with diagnostic rounded and broad tips. Squarish head profile with striking crest. Winter and juvenile plumage with scaled back, and less contrasting breast band.

Sound:

Quite vocal, especially in flight at breeding ground. Territorial call: Dry, introductory phrases followed by drawn-out mewing sounds; "wyrrr-peeeoo-weeep". Alarm call "pee-wit".

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

Appearance:

White forehead with white wedge above eye in all plumages. Legs, and most of bill yellow in adult breeding plumage. Very small and longwinged tern. Only 2/3 of size of Common Tern. Head and bill proportionally longer than Chlidonias species and congeners, while tail is shorter. Back paler grey and belly whiter. First primaries form a dark front edge to wing. In winter the bill darkens, legs turn a dirty yellow and the white forehead expands. Juvenile resembles adult winter, but has yellowish bill base and scale patterned back. Flight fluttering with rapid wing-beats, which together with size, is usually sufficient to determine the species.

Sound:

Fairly distinct voice. Contact call a sharp "kitt", often combined to form undulating, rolling series. Not as sharp and penetrating as Common- and Arctic Tern.

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

Featherbase

CC

CC-photo:Lars Buckx, Licence,Link.