White-winged Tern (Chlidonias leucopterus)
Short-toed Treecreeper (Certhia brachydactyla)
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.
Very similar to Treecreeper C. familiaris, and id by sound generally easier than by appearance in areas where both species occur. Primaries with small, almost pure white tips restricted to outer web. Hind-claw shorter than hind-toe. Wing-bar usually with even "steps", but often difficult to determine. Underparts less white and more brownish than in continental C. familiaris (which again is browner than the pure white northern subspecies). Bill longer and with a stronger curved tip.
Sound:Contact call very similar to C. familiaris. A thin "sreee" often repeated in an even rhythm, perhaps with slighly shorter pauses. Flight call a short and sharp "wit" used freely when moving about. Song diagnostic, and introductory notes often used singly when interacting. Full song starts with one or two staccato introductory notes, the first higher pitched than the second, followed by a rapid, ascending crescendo ending in a drawn-out, less pure "sree". The tone is loud and much more penetrating and clear than C. familiaris. Timbre recalls wet rubber-boots on vinyl flooring. Note that "mixed singers" of C. familiaris are not uncommon in areas where both species of treecreepers occur.
Song:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-photo:Agustín Povedano, Licence,Link.