Appearance:

A large shearwater with pale upperparts and heavy, yellowish bill. Large grey head. The grey neck forms a diagnostic, contrasting line from wing base to base of bill (most other shearwaters have white neck-sides). Armpits usually pure white. Underside of wings white, framed by black flight feathers. Flight action calm and distinct. Long glides alternates with 3-4 slow wingbeats. Wingtips always bent downwards, and wings slightly angled back. Often soars. Differs from Fulmar in dark tail, grey head, long, narrow wings and longer bill. The two subspecies C. diomedea and C. borealis, are somtimes treated as different species. Field identification of these usually impossible, and requires ideal conditions. Hand of borealis is darker due to no white fringes to primaries. In diomedea the white in the coverts extends in a white wedge into the hand, through the base of the primaries.

Sound:

Very vocal at breeding ground. Calls with a very nasal, comical, mewing "ke-kooeee", ending with falling pitch, like a releasing sigh or moan. Sometimes reltively pure, other times very hoarse and raucous.

At breeding ground (C. d. borealis):

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:James Bradley, Licence,Link.

CC-photo:Hans Verdaat, Licence,Link.

Appearance:

Largest marsh tern. Liable to confusion with Sterna terns due to black cap, in addition to other marsh terns. All marsh terns (Chlidonias) differs from Sterna by lack of tail streamers, short tail with shallow fork, shorter wings and stiffer flight. Marsh terns don't plunge-dive for food but picks from surface (though Whiskered Tern may belly-plunge), mostly in fresh water. Adult Whiskered Tern easily told from other marsh terns by distinct black cap contrasting to white cheeks and throat. Underwing pale with diffuse dark trailing edge. Belly distinctly darker than Common- and Arctic Tern, but beware of variation in both species. Bill dark blood red. Adult winter: Very pale with no distinct markings except for ill-defined black mask stretching from eye to eye across nape. Forehead white and with crown white speckles. Bill black. Immature: Yellowish brown saddle with coarse dark pattern, though these are moulted in early autumn. Usually lacks dark carpal bar and cap ill-defined. Whiskered Tern generally stockier built than other marsh terns. Both immatures and adult winter show grey rump (different from Common, Arctic and White-Winged), and bill is dagger-shaped (most apparent in males).

Sound:

Contact call freely used and fairly distinct: An extremely hoarse, and rasping "krreek" in various moods. Timbre comparable to Corncrake. Sometimes uttered in stuttering series "kr-kr-kr-kr-kr".

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-sound:Patrik Åberg, Licence,Link.

CC-photo:Jurrien van Deijk, Licence,Link.

CC-photo:Geert Moris, Licence,Link.

CC-photo:Michel Kapoen, Licence,Link.

CC-photo:Ria Vogels, Licence,Link.