Pallid Swift (Apus pallidus)
Arctic Tern (Sterna paradisaea)
Very 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/
Differs from Common Tern in shorter head, and blood-red bill. Legs shorter, but tail streamers longer (extends well past wings in sitting birds). Underparts of primaries with sharply bordered dark trailing edge (diffusely bordered in Common Tern). Both primaries and secondaries transparent to sunlight. Crest less apparent than in Common Tern and underside greyer. Cheeks white just below the black cap, often in contrast to grey lower cheeks. Juveniles lacks buff coloured back.
Sound:Similar to Common Tern but higher pitched. Typical call a series of high pitched "tip-tip-tip", and longer, ringing, high-pitched "kriiiiii" calls. The drawn out "kree-aaahh" call falls less distinctly in pitch than Common Tern.
Calls:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CC