Cassin's auklet is a small, chunky seabird that ranges widely in the North Pacific. It is the only species placed in the genus Ptychoramphus. It nests in small burrows and because of its presence on well studied islands in British Columbia and off California it is one of the better known auks. It is named for the American ornithologist John Cassin.
Region
North Pacific Ocean (eastern and central)
Typical Environment
Breeds on offshore islands from the Aleutian chain and Gulf of Alaska south through British Columbia to Washington, Oregon, and California, reaching Baja California and Guadalupe Island. Outside the breeding season it disperses widely over the California Current and into the Gulf of Alaska, often far from land. It favors productive continental-shelf waters, fronts, and upwelling zones. Nests are placed in burrows dug into soil or in rock crevices on predator-free islands. At sea it remains low to the water and often associates with other seabirds over feeding hotspots.
Altitude Range
Sea level to 300 m
Climate Zone
Temperate
Ease of Keeping
Beginner friendly: 1/5
Cassin's auklet is a small, chunky seabird of the North Pacific and the sole member of its genus. It nests in burrows and visits colonies mostly at night to avoid predators. In exceptionally productive years, some colonies can raise two broods in a season—unusual among seabirds. It feeds largely on krill and other zooplankton concentrated by coastal upwelling.
Temperament
social and active at sea; secretive and mostly nocturnal around colonies
Flight Pattern
short rapid wingbeats, low over the water
Social Behavior
A strictly colonial burrow nester; pairs are generally monogamous and both adults incubate and feed the chick. Adults commute at night to reduce predation by gulls and raptors. Chicks are often left unattended in the burrow during the day and fledge at night. In some southern colonies, pairs may attempt a second brood in years of high food availability.
Migratory Pattern
Partial migrant
Song Description
At colonies it gives soft, purring trills and squeaky, cooing notes from within burrows, mostly at night. At sea it is usually silent.
