Great Skua (Stercorarius skua)
White-winged Tern (Chlidonias leucopterus)
Large and heavy skua with broad wings and short tail. The white patches at base of primaries are more striking than in the other skuas, and are visible both on upper and underside of wings. Size comparable to Herring Gull, but build more compact. Seemingly black at a distance, but white wing-patches usually visible. Confusion with juvenile Pomarine Skua possible, but body is heavier (not just the chest), wings rounder, bill longer, neck thicker and tail shorter.
Sound:Heard mostly at breeding ground. Short, and dry "kek", when agitated. Also a nasal, slightly mewing "kew".
Alarm call:
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.