Alpine Chough (Pyrrhocorax graculus)
Arctic Tern (Sterna paradisaea)
All black plumage, red legs and relatively short and straight, yellow bill. Note that immature Red-billed Chough has yellowish-brown bill, but never as pure yellow as in Alpine Chough, and the whole bill is curved. Easily confused with Red-billed Chough at a distance where both species occur, but note more narrow, less fingered wings, and longer, more rounded tail. Resembles Jackdaw in size, but flying Alpine Choughs differs by two-toned underparts of wings (darker coverts). Flight acrobatic, but a little more stilted than Red-billed Chough.
Sound:Diagnostic and very different from Red-billed Chough. A sharp, quite high-pitched, whistling trill "chreeeee". Usually alternated with pure-toned high-pitched whistles, falling abruptly in pitch with a "clipping" ending.
Contact call:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCDiffers 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