Appearance:

A large shearwater with pale upperparts and heavy, yellowish bill. Large grey head. The grey neck forms a diagnostic, contrasting line from wing base to base of bill (most other shearwaters have white neck-sides). Armpits usually pure white. Underside of wings white, framed by black flight feathers. Flight action calm and distinct. Long glides alternates with 3-4 slow wingbeats. Wingtips always bent downwards, and wings slightly angled back. Often soars. Differs from Fulmar in dark tail, grey head, long, narrow wings and longer bill. The two subspecies C. diomedea and C. borealis, are somtimes treated as different species. Field identification of these usually impossible, and requires ideal conditions. Hand of borealis is darker due to no white fringes to primaries. In diomedea the white in the coverts extends in a white wedge into the hand, through the base of the primaries.

Sound:

Very vocal at breeding ground. Calls with a very nasal, comical, mewing "ke-kooeee", ending with falling pitch, like a releasing sigh or moan. Sometimes reltively pure, other times very hoarse and raucous.

At breeding ground (C. d. borealis):

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

CC-sound:James Bradley, Licence,Link.

CC-photo:Hans Verdaat, Licence,Link.

Appearance:

Very similar to Crested Lark, and identification can be very difficult in areas where both species occur. The much used streaked-breast character is not always relevant because of regional variations among the many subspecies of both Crested and Thekla. Then habitat, behaviour and voice becomes important for identification. A combination of the following characters should be used to tell it from Crested: Bill appears straight (because of convex lower mandible), crest fuller and not so pointed, belly less deep, back more heavily streaked , tail coverts rusty-brown in contrast to rump, underwing coverts greyish white (not rufous), upper breast with defined streaking ("done with marker pen"). Eye-stripe white behind eye. Will often perch atop of scrubs or bushes, unlike Crested, and usually prefers higher altitude habitats.

Sound:

Song: a mix of long whistling, warbling sounds, trills and mimicry. Full song very similar to Crested Lark. Rudiments of song are often heard and is less whistling than Crested. The contact call/alarm-call may be the best characteristic to separate it from Crested Lark where both species occur. Thekla Lark calls with 3-5 syllables, of which one is often drawn out and "hangs" while falling in pitch, giving it a melancholic feeling (diagnostic). The phrase has a more "bouncing" feel to it than Crested Lark.

Call and song (diagnostic call at time 08-11 sec.):

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