Appearance:

Summer: Red throat (seemingly black at a distance!). Lacks white vertical framing of throat patch and white spotted back of Black-throated Diver. Winter: Quite pale. White face and eye-ring. Just a narrow stripe of dark grey along the back of the neck. In all plumages best identified by posture and silhouette, especially when seen at a distance. Slender neck, head and bill. Flat chest. Usually shows no white flank patch. Bill usually held uptilted.

Sound:

In flight; nasal, dry, gooselike series of rhythmic cackling "ko-ko-ko". Most vocal when courting and breeding. A meowing drawn-out sound starting with a register break, then falling in pitch. Display call a far reaching rolling cyclic cooing, given in long sequences.

Song/display:

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:Lauri Hallikainen, Licence,Link.

Appearance:

Large tern with black bill, with yellow tip (adults). Bill all black in juveniles. Long black cap and shaggy crest. Generally leaves a much whiter impression than other terns in the region (except Roseate Tern). Adult summer: Yellow bill-tip. Tail pure white, and upperparts pale grey. Outer primaries darker than rest of wing, and contrast increases in worn plumage. Broad white trailing edge to inner wing. Underside of primaries with faint narrow dark trailing edge. Forehead white in adult winter and first winter plumage. Juveniles: scaly upperparts and dark bill. Less evenly coloured than juvenile Gull-billed Tern. First winter birds similar to juveniles, but back purer grey and bill shorter. Can be mistaken for Gull-billed Tern, but note different profile. Flight powerful with evenly narrow wings and a front-heavy appearance, due to the long head and bill. Often dives from high above the surface and stays under water longer than Common and Arctic T.

Sound:

Contact call a sharp and grating "keeree-eek". Often compared to the pressing of amalgam into a tooth.

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:Paul:Ritchie, Licence,Link.

CC-sound:Peter Boesman, Licence,Link.