Other Names: none
Distribution: North Atlantic waters.
Size: 38-43 cm in length with a 60-69 cm wingspan.
Plumage: Breeding adults are black above and on the head and white below; the very deep, laterally compressed bill has white bands in adults. Non-breeding adults have some white coloration on the throat and cheek, and behind the eye. Juveniles have smaller, unmarked bills. The legs and eyes are white.