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:

Large tern with black bill, with yellow tip (adults). Bill all black in juveniles. Long black cap and shaggy crest. Generally leaves a much whiter impression than other terns in the region (except Roseate Tern). Adult summer: Yellow bill-tip. Tail pure white, and upperparts pale grey. Outer primaries darker than rest of wing, and contrast increases in worn plumage. Broad white trailing edge to inner wing. Underside of primaries with faint narrow dark trailing edge. Forehead white in adult winter and first winter plumage. Juveniles: scaly upperparts and dark bill. Less evenly coloured than juvenile Gull-billed Tern. First winter birds similar to juveniles, but back purer grey and bill shorter. Can be mistaken for Gull-billed Tern, but note different profile. Flight powerful with evenly narrow wings and a front-heavy appearance, due to the long head and bill. Often dives from high above the surface and stays under water longer than Common and Arctic T.

Sound:

Contact call a sharp and grating "keeree-eek". Often compared to the pressing of amalgam into a tooth.

Contact call:

Distribution:

Xeno-canto: map

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:Paul:Ritchie, Licence,Link.

CC-sound:Peter Boesman, Licence,Link.