Common loon in winter plumage
Gavia immer

f6.7 @ 1/2500s, ISO:1000, Nikon D3S w 500mm and 1.7X tele-converter

"Great Northern Loon," Wikipedia, the free encyclopedia. Non-breeding plumage is brownish, with the chin and foreneck white. The bill is black-blue and held horizontally. The bill color and angle distinguish this species from the similar Yellow-billed Loon.
Cape Cod Canal, Sandwich, Massachusetts