Appearance:

Differs from Common and Arctic Tern by; noticably shorter wings, longer streamers, much paler grey upperparts, pure white underparts (faint rosy wash not very conspicuous), black bill (red base in breeding birds), dark outer primaries and no dark edge to inner primaries. Amount of red in bill increases as breeding season progresses, but also varies geographically. Wingbeats shallower and much quicker than in Common and Arctic Tern. Fishes with characteristic diagonal dives. Despite the long streamers, the birds appear short-tailed in flight, but head and bill are long and slender. The pale plumage, dark bill and giss recalls a small Sandwich Tern. Adult winter plumage with all dark bill and white forehead. Juveniles resembles juvenile Sandwich Terns, with more complete dark cap than Arctic and Common, and much more contrasting markings on back (especially to wings).

Sound:

Extremely harsh calls. Like mix of Caspian and Arctic Tern. Very hard and raspy "kreeeet", harder and higher pitched than Caspian Tern, but equally harsh. Other calls include more Arctic/Common tern-like short "kek", and similar.

Contact call:

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

CC

CC-photo:USFWS/Southeast, Licence,Link.

CC-photo:Werner Witte, Licence,Link.

CC-photo:Anita363, Licence,Link.

CC-photo:Mike Prince, 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