An Arctic seabird. In Svalbard, it breeds on narrow cliff ledges; chicks head to sea with a parent before they can fly.
Males and females look alike. The stout bill has a white line; in breeding plumage the head and back are black above a white underside. In winter, the neck and throat are also white. Its length is 39–43 cm; adults weigh 700–1200 g.
It nests in dense colonies on narrow ledges near the sea and feeds mainly on fish and crustaceans. Chicks leave the ledges before they are fully fledged and head to sea with a parent.
It lays one pear-shaped egg. Both sexes incubate it for about 32 days. The chick jumps from the breeding ledge at about 20–21 days after hatching and is accompanied to sea by one parent, usually the male.
An extinction-risk assessment has not been added yet.