Brunnich's Guillemot
Uria lomvia

f6.3 @ 1/2500s, ISO:1600, Nikon D3S w 300mm

"Thick-billed Murre," Wikipedia, the free encyclopedia.The thick-billed murre and the closely related common guillemot (or common murre, U. aalge) are similarly-sized, but the thick-billed still bests the other species in both average and maximum size. The thick-billed murre measures 4048 cm (1619 in) in total length, spans 6481 cm (2532 in) across the wings and weighs 736-1481 g (1.6-3.3 lb).They differ from the common murre in their thicker, shorter bill with white gape stripe and their darker head and back; the "bridled" morph is unknown in U. lomvia - a murre has either a white eye-stripe, or a white bill-stripe, or neither, but never both; it may be that this is character displacement, enabling individual birds to recognize conspecifics at a distance in the densely packed breeding colonies as the bridled morph is most common by far in North Atlantic colonies where both species of guillemots breed. In winter, there is less white on the thick-billed murre's face. They look shorter than the common murre in flight. First year birds have smaller bills than adults and the white line on the bill is often obscure, making the bill an unreliable way to identify them at this age. The head pattern is the best way to distinguish first-year birds from common murres.
Alkefjellet, Svalbard, Norway