Treecreeper (Certhia familiaris)
Arctic Tern (Sterna paradisaea)
Unmistakable, except in areas where it coexists with Short-toed Treecreeper. Differs from said species in pure white flanks (sub-species macrodactyla has faintly buff flanks but not as marked as in Short-toed), shorter and only moderately curved bill, hind-claw as long as hind-toe and "notched" wing-bar (uneven "steps"). Tips of primaries with buffish/white tips/fringes extending along inner web. Mostly distinguished from Short-toed by call, and identification exclusively by plumage characters difficult in areas where both species occur.
Sound:Contact call a drawn, high-pitched "tzreeee". Similar to Goldcrest in timbre, but of longer duration with a vibrating and slightly rolling tone. Generally repeated in evenly paced, slow series (unlike Goldcrest). Song a short, continuous three-part phrase. Each phrase starts with a few contact call-like notes followed by a Willow Warbler-like descending part, which then jumps to a few descending high notes to form a marked conclusion. Note that "mixed singers" are not uncommon in areas where both species of treecreepers occur.
Song:
Distribution:
Xeno-canto: map
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