Pigeon Guillemot

The Pigeon Guillemot, Cepphus columba, is a medium-sized seabird of the auk family, Alcidae. Exhibiting sexual monomorphism, both sexes share a similar appearance, with a length of 30 to 37 cm and a weight of 450 to 550 grams. In breeding plumage, adults are cloaked in dark brown feathers with a black iridescent sheen, punctuated by a distinctive white wing patch marred by a brown-black wedge. Come winter, they don a mottled grey and black upperparts with white underparts. Their long bill, claws, and the inside of their mouth are a striking black, while their legs, feet, and mouth interior are a vivid red.

Identification Tips

To identify the Pigeon Guillemot, look for its red legs and feet, and the black bill during the breeding season. The white wing patch with a dark wedge is a key feature, as is the bird's upright posture and ability to walk well on land. Juveniles resemble winter adults but have brown-tipped underpart feathers and a smaller wing patch.

Habitat

These birds are found on rocky shores, cliffs, and islands in close proximity to shallow waters, where they breed and sometimes roost. They prefer areas that offer protection from predators and are more commonly found on offshore islands than on coastal sea cliffs.

Distribution

The Pigeon Guillemot's range spans the North Pacific coastal waters, from Siberia through Alaska to California. In winter, some birds migrate slightly south or north, depending on their location, generally seeking more sheltered areas.

Behaviour

Pigeon Guillemots are diurnal, often sleeping in loose groups on sheltered waters or shores. They exhibit strong swimming capabilities on the surface and are adept divers, using both wings and feet for propulsion underwater.

Song & Calls

This species is quite vocal, especially during the breeding season. Calls include the hunch-whistle, trill, and low whistle, which serve various purposes from territory defense to mate attraction. The red coloration of the mouth may also play a role in communication.

Breeding

Monogamous breeders, Pigeon Guillemots nest in small colonies, defending territories around their nesting cavities. They lay one or two eggs, which both parents incubate and later feed the chicks. After fledging, the young are independent.

Similar Species

The Pigeon Guillemot can be confused with the Black Guillemot but is distinguished by its larger size and the dark wedge on its wing patch during the breeding season.

Diet and Feeding

Their diet consists of small fish and marine invertebrates, which they catch by pursuit diving near the sea floor. They forage alone or in small groups, often close to shore and within a kilometer of their colony during the breeding season.

Conservation status

The Pigeon Guillemot is classified as Least Concern by the IUCN. Its population is large and stable, with an estimated 470,000 individuals across a vast range. However, they face threats from climate change, introduced predators, and oil spills.