Bucephala albeola
The Bufflehead is one of the smallest of the sea duck group. The drake has a black head with a green and purplish sheen and a blue gray bill. Behind the eye is a large white patch stretching around the head. The back is black and the breast, sides and belly are white. The hen is brown with a white patch on the cheek and a gray bill. The hen's underside is light brown. (source: Flyways.us)