White-winged Tern (Chlidonias leucopterus)
Gyrfalcon (Falco rusticolus)
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.
Largest falcon. Heavily built. Grey upperparts and white, speckled underparts. Juveniles with browner plumage than adults, blue-grey legs and longitudinal streaking below. Diffuse moustache-stripe, and the whole head seems dark at distance, lacking a defined cap. Rounder and broader wings, longer tail and bulky belly distinguishes it from Peregrine. Underside of wings with dark coverts in contrast to pale base of flight-feathers. Extremely powerful, but slower flight action than Peregrine.
Sound:A coarse, drawn out, Peregrine-like "kaaawt", with emphasis on ending, is repeated in series. Much slower paced than in small falcons, and deeper and with different attack than in Peregrine. Also shorter, coarse warning-calls.
Alarm call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCSounds:Recorded by Andrew Spencer,http://www.xeno-canto.org ,CC license