Scottish Crossbill (Loxia scotica)
Citrine Wagtail (Motacilla citreola)
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.
Adult male easily recognized with all yellow head with dark edges and grey back. Prominent white wing-bars and all dark bill, lacking the pale base of Yellow Wagtail. Females and adult winter lacks the dark lore-stripe of Yellow Wagtail, and the flanks are grey. The same applies to the juveniles. These also give a very grey impression, almost resembling a Pied Wagtail without the dark breast-pattern. Juvenile Yellow Wagtails have a less grey and more olive tone to their backs. The dark facial markings/earcoverts of females/winter/juveniles birds are usually framed by the continuation of the strong supercilium. Some Yellow Wagtails are very similar to Citrine, and call and tail length should be considered as well (tail longer in Citrine).
Sound:Contact call resembles Yellow Wagtail, but is harsher with a more buzzing quality, and of shorter duration. The pitch is more constant, lacking the rise and fall of Yellow Wagtail. The song is a loose repetition of phrases, comprised of disyllabic or monosyllabic contact calls.
Contact call:
Distribution:
Wikipedia: map (se also Xeno-canto below)
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCSounds:Recorded by Jelmer Poelstra,http://www.xeno-canto.org ,CC license