Cepphus

Cepphus 

a genus of birds of the family Alcidae. The body is 32–40 cm long and weighs 340–600 g. The bill is black, straight, and thin. The plumage of the adults is black in summer and mottled in winter. The feet are red. The birds fly, swim, and dive well, but they walk poorly. The diet consists of small fishes and marine invertebrates. The birds nest in groups in the crevices of cliffs or amid rocks. The clutch usually contains two eggs. The young are born with dense, soft, dark down; they leave the nest fully fledged.

There are two (or three) species. The black guillemot, or sea pigeon (C. grylle), lives along the coasts of the Arctic, North Atlantic, and Pacific oceans; those occurring in the Pacific are sometimes regarded as the separate species C. columba. The sooty guillemot (C. carbo), which has a white circle around the eyes, is common along the coasts of the seas of Okhotsk and Japan. In some places the birds are used commercially for their meat and eggs.