Photos: 6
Forms: 3 (Breeding/sinensis/hanedae, Non-breeding/carbo, Non-breeding/sinensis/hanedae)
Eurasian (sinensis/hanedae)North Atlantic (carbo)
IE-LIS-3JP-28
5ISSF, 1Form; mostly geographically split but Eurasian is widespread with some overlap.
Plumage varies, with breeding showing more white on cheeks, neck, and thigh while non-breeding is mostly sleek black with gloss of blue/green depending on part of body.
M/F similar.