Appearance:

Unmistakable, if not in silhouette. In poor light or at a distance, when the grey plumage is not visible, confusion with other crows is possible. Bill is deeper than in Rook, and the upper mandible more curved towards the tip. Smaller than raven, and much less heavy bill. The wings are shorter and more rounded, and the tail is not wedge-shaped. Posture less upright than Rook.

Sound:

Cawing is aggressive and more raucous than in Rook, with more rolling r's. Has a large repertoire of seldom heard calls, and even sub-song. Many of these calls are surprisingly resonant and pleasant sounding, and sometimes resembles Raven. Probably impossible to tell from Carrion Crow with certainty by sound alone.

Cawing:

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

Appearance:

Yellow legs, black to dark grey back (regional variations) and black primaries with only small white spots. Generally more slender than Herring Gull and Great Black-backed, with longer and more narrow wings, and longer legs. Winter plumage with streaked head and neck. Underside of flight feathers smoky grey. Juveniles very variable, but generally darker than Herring Gulls. Young birds with completely dark inner primaries and broad terminal band to tail.

Sound:

Very similar to Herring Gull, but tone more nasal.

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

Sounds:Recorded by Peter Boesman,http://www.xeno-canto.org ,CC license