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 similar to Treecreeper C. familiaris, and id by sound generally easier than by appearance in areas where both species occur. Primaries with small, almost pure white tips restricted to outer web. Hind-claw shorter than hind-toe. Wing-bar usually with even "steps", but often difficult to determine. Underparts less white and more brownish than in continental C. familiaris (which again is browner than the pure white northern subspecies). Bill longer and with a stronger curved tip.

Sound:

Contact call very similar to C. familiaris. A thin "sreee" often repeated in an even rhythm, perhaps with slighly shorter pauses. Flight call a short and sharp "wit" used freely when moving about. Song diagnostic, and introductory notes often used singly when interacting. Full song starts with one or two staccato introductory notes, the first higher pitched than the second, followed by a rapid, ascending crescendo ending in a drawn-out, less pure "sree". The tone is loud and much more penetrating and clear than C. familiaris. Timbre recalls wet rubber-boots on vinyl flooring. Note that "mixed singers" of C. familiaris are not uncommon in areas where both species of treecreepers occur.

Song:

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

CC-photo:Agustín Povedano, Licence,Link.

CC-photo:Agustín Povedano, Licence,Link.

CC-photo:Mickaël Dia, Licence,Link.