Appearance:

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

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

CC

Collage 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.

Appearance:

Very deep and heavy, conical bill. Large head and bull-neck, gives the bird a front-heavy appearance, especially in flight. The short tail adds to the impression. Wings with broad, white bars and tail with white terminal band. Bill grey in breeding plumage, and yellowish in winter. Largely unmistakable, but easily overlooked when hiding high in foliage. Often flies high, even for short distances. Flight heavily undulated.

Sound:

Most typical call a sharp and explosive "tzek", with abrupt, emphasized, cut-off ending. Quite similar to Robin, but harder, with each syllable marginally longer with a slightly wheezing timbre. Repetitions are slower and more singular than Robin. Diagnostic when interspersed with high frequency notes.

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

Featherbase

CC