White-winged Tern (Chlidonias leucopterus)
Gannet (Morus bassanus)
Breeding 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.
White with black wing tips and yellow-buff at back of head. Juveniles brown with small pale speckles, white u-shaped rump patch and pale underparts. Fully coloured only after 5 years, and patchy, intermediate plumages often seen. Unmistakable bird at close range or with favorable light, but can be confused with shearwaters at a distance and/or in strong wind. Differs from those by long tail and much longer neck and head. Alternates between powerful, even and shallow wing-beats and glides. Flight becomes more shearwater-like in strong winds.
Sound:Heard mostly at breeding ground. Even, rhythmical series of harsh "harrr, harrr, harrr,".
Social interaction:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCSounds:Recorded by Elias A. Ryberg,http://www.xeno-canto.org ,CC license