Red-throated Loon (Gavia stellata)
White-winged Tern (Chlidonias leucopterus)
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
Image search Flickr NB! May give other species
CCBreeding adult easily identified by white tail/rump combined with jet black under wing coverts and silvery upper wing. Immature with brownish back contrasting with pale, silvery upper wings and pale rump. Broad white collar, and lacks dark breast patch of immature Black Tern. Adult winter most liable to confusion with other terns, but upperparts much paler than Black Tern. Contrasting dark outer primaries and secondaries to rest of wing. Often retains some black under coverts even in winter which is diagnostic if seen. Slightly more compact than Black Tern and often recalls Little gull in shape. Bill noticeably shorter and thinner than in Whiskered Tern.
Sound:Mostly silent away from breeding ground. Most diagnostic call a dry, rolling "krrrrrr-ta-ta" where the rolling is followed by one or two accentuated syllables, or just simply "krrrrrr". Used in excitement.
Call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-sound:Marco Dragonetti, Licence,Link.