Willow Warbler (Phylloscopus trochilus)
Short-toed Treecreeper (Certhia brachydactyla)
Olive green upperparts, yellowish chest with gradual transition to off-white belly. Very similar to Chiff-chaff, and most field characters are subtle and often hard to see. Distinguished by (usually) pale, yellow-brown legs, dark framing to ear-coverts, stronger supercilium. Long primary projection (often 3/4ths the length of tertials) with irregularly spaced tips (visible when wing folded). Wings slightly more pointed than in Chiff-chaff, and not so fan-shaped. Juveniles often with whole underparts yellow. Frequently flicks tail, but not sideways (unlike Chiff-chaff). Generally also more calm when moving among the foliage.
Sound:By far most easily identified by it's call or song. Contact/alarm call a soft, plaintive ascending "hoo-eet". Similar to Chiff-chaff, but first part more drawn, giving it a disyllabic feel. Song: A 3-5 second, falling phrase of soft, rippling "svi-svi" sounds, starting high with some attack, and then falling in a mellow manner. The phrase lacks any conclusion, and diminishes both in strength and tempo.
Song:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCVery 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.