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:

Large and bulkily built diver with heavy bill, square head profile and steep forehead. Usually holds bill pointed straight, not uptilted like White-billed Diver. Summer: White underparts and chequered black back. Black bill and head. Neck with white band. Winter; white underparts and dark back. Neck with incomplete black band, creating contrasting, jagged edge. Heavy, goose-like flight.

Sound:

Song: Like a slow Black-throated Diver. Pitch slowly rising with a register break, progressing into a cyclic, two to four syllable, motif. Also various vibrating eerie descending calls. Often used as sound effect in horror movies.

Song:

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:jackanapes, Licence,Link.

CC-photo:jerryoldenettel, Licence,Link.

Sounds:Recorded by Patrick Åberg,http://www.xeno-canto.org ,CC license