Scottish Crossbill (Loxia scotica)
Thekla's Lark (Galerida theklae)
Only in the UK. Similar to Red and Parrot Crossbill in plumage. Bill size possibly the only visual identification clue, but even this overlaps with the other two species. Bill is usually deeper and heavier than Red Crossbill. Certain separation from Parrot Crossbill in the field by visual characters alone, probably not possible. Species status mainly upheld by isolated breeding population and differences in excitement calls from other crossbills. Calls probably play an important role in maintaining the reproduction barrier between Crossbill populations with different bill-size. See Birdlife link below for more info.
Sound:Calls very similar to Parrot Crossbill, and sonogram analysis may be needed for certain identification. Flight and excitement calls show most unique quality. Sonogram image above by Ron Summers (used with permission). A detailed article about crossbill calls can be found here.
Distribution:Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCollage photo By Richard Crossley (The Crossley ID Guide Britain and Ireland) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons.
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
Image search Flickr NB! May give other species
CC