Scottish Crossbill (Loxia scotica)
Subalpine Warbler (Curruca cantillans)
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.
Medium small Sylvia with short tail, slender body and steep forehead. Bill slim,fairly short and pointed. Male with rufous breast and conspicuous, broad, white moustache stripes. Upperparts lead grey. Female with slightly more brownish upperparts and buff white below. Immature birds has greyish brown upperparts, and are prone to confusion with Spectacled Warbler due to broad, brown fringes of tertials. The colour is however less rufous, and the dark centre ends in a rounded, not pointed tip. Pale legs in all sexes and ages, but some variation. Eye-ring colour variable, but generally red in male and very pale in female and immature (rules out other Sylvia except Tristram and Sardinian). Colour of upperparts more uniform than in confusion species in both male and female. May cock tail, but does not keep it raised like Dartford Warbler. Taxonomy much discussed. Western Italian population now accepted as a separate species (Moltoni's Warbler, S. subalpina), while S. c. inornata has species status in Svensson, but not in Clements (2018) .
Sound:Alarm call a short, hard "tuk", but softer and fainter than Blackcap and Sardinian W. Song a rapid, vivid stream of squeaks and clearer notes, with timbre similar to Whitethroat. May be confused with Sardinian W., but lacks that species interwoven hard and rolling contact call.
Alarm, song:
Distribution:
Xeno-canto: map
Ecology:Birdlife ecology
Links:
Observation.org Latest observations
Image search Flickr NB! May give other species
CCCC-photo:adrien2008, Licence,Link.