Appearance:

Olive green upperparts, yellowish chest with gradual transition to off-white belly. Very similar to Willow Warbler, and most field characters are subtle and often hard to see. Distinguished by (usually) black, or dark-brown legs, only faint dark framing to ear-coverts, less marked supercilium. Shorter primary projection (1/2 to 2/3'rds the lenght of tertials), with regularly spaced tips (visible when wing folded). Wings more fan-shaped and less pointed than in Willow Warbler. Juveniles much less yellow below than in W.Warbler. Generally leaves a duller and greyer impression than W. Warbler, but plumage very variable. Frequently flicks tail, even sideways. Generally also more active when moving among the foliage.

Sound:

Contact/alarm call a soft, plaintive ascending "hooeet". Similar to W.Warbler, but shorter with a monosyllabic feel. Song a very distinct: "chiff-chaff-chiff-chiff-chaff-chiff", in a regular clock-like rhythm. Each syllable at seemingly random pitch, but no large intervals tonally. Sometimes "get stuck" at one note.

Contact call, song:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase

CC

Appearance:

Adults in summer at close range unmistakable. Bill in juveniles almost black, and much less deep than in adults. Adults in winter plumage also show much darker bill and cheeks than in summer. At a distance head gives an all dark impression, with characteristic dark "shadow " in front of the eye. Head and bill less elongated than in other auks. Wings rounded with dark undersides. "Thighs" dark. Flight fluttering and energic, with shifting weight and angle.

Sound:

Deep, but not so coarse as Razorbill. Smoother and more gliding changes in pitch, like a "slow-motion" laugh or distant chainsaw; "aaaahrrr, aahr, ahr arh".

Contact call:

Distribution:

Wikipedia: map (se also Xeno-canto below)

Ecology:

Birdlife ecology

Links:

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase

CC

CC-photo:zanzamos, Licence,Link.

Sounds:Recorded by Hans Petter Kristoffersen,http://www.xeno-canto.org ,CC license