Caspian Tern (Hydroprogne caspia)
Short-toed Treecreeper (Certhia brachydactyla)
Very large tern, with deep, dagger-like, blood-red bill with dark tip. Large, black cap reaching well below the eyes. Grey upperparts and white underparts. Rather short tail. Outer primaries distinctly darker than the rest of upperwing, and outer underwing almost black. Unmistakable from the size alone, and leaves a gull-like impression, lacking the elegance of smaller terns. Immatures with paler bill and white forehead (as in adult winter), and markedly speckled back. Hovers and dives. Often rests on the surface, feeding like a gull.
Sound:Easily recognized by its very harsh calls. Sometimes likened to the sound of a plate of steel being dragged across a concrete floor. Similar in harshness to Grey Heron, but more drawn, with an accented middle; "Kraaeeet", or with a double syllable start "ka-ha-kraaaeet". Immature birds begs with a penetrating, sharp whistle.
Contact 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
CCCC-photo:lgooch, 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.