Arctic Loon
Gavia arctica

f9 @ 1/1250s, ISO:640, Nikon D300 w 500mm

"Black-throated Loon," Wikipedia, the free encyclopedia. Breeding adults are 58 to 77 cm (23 to 30 in) in length with a 100 to 130 cm (39 to 51 in) wingspan, shaped like a smaller, sleeker version of the great northern diver. Body mass is reportedly from 23.4 kg (4.47.5 lb). They have a grey head, black throat, white underparts and chequered black-and-white mantle. Non-breeding plumage is drabber with the chin and foreneck white. Its bill is grey or whitish and dagger-shaped. In all plumages, a white flank patch distinguishes this species from all other divers including the otherwise almost identical Pacific diver.
Suomussalmi, Finland