Willow Ptarmigan (Lagopus lagopus)
Pallid Swift (Apus pallidus)
Slightly bigger and more heavy build than Ptarmigan, with clearly heavier bill. Summer plumage warm brown above with white belly, showing a warmer brown than Ptarmigan. Winter plumage all white in both sexes, except for black tail. Males lacking black lores. Wings always white in all plumages in nominate ssp. lagopus, and brown in ssp. scotica.
Sound:Very characteristic calls: "Kuwa -Kuwa -Kuwa" (go back!) Also: "kauw kauwkkkrrrkekekekekeke" with a short pause after first "kauw", then a decelerating cackle, often followed by the "go back" call.
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 Common Swift, and often difficult to identify in the field. Seeing the birds against a darker background, as opposed to the sky, brings out some of the characters more clearly. Generally paler and more sandy brown than Common Swift. Differs further from C. Swift by: Rounder wing tip (outermost primary shorter than the next), slightly broader wings, broader and flatter head. White throat patch bigger and more prominent. The face seems paler, which brings out the dark eye-mask. Back slightly darker than upper part of wings. More contrast between outer and inner primaries. Underparts with more pronounced scaly pattern. Flight less acrobatic, with slightly slower wing-beats, more frequent gliding and much less twinkling turns.
Sound:Similar to Common Swift, but usually very helpful for ID. Almost di-syllabic, with marked accent on second syllable which rapidly drops in pitch, "srrrree-aah". Common swift has a more even call, with accents on first part, without the sudden pitch-drop.
Contact call:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCSound recording:Creative Commons,www.xeno-canto.org,Carlos W.,http://creativecommons.org/licenses/by-nc-sa/4.0/