Aethia

Aethia is a genus of small seabirds in the auk family Alcidae, commonly referred to as auklets. They are found across the North Pacific and Arctic, and breed on rocky islands and coastal cliffs where they form large colonies. Members of Aethia are among the smallest alcids, with short wings adapted for rapid diving and swimming. They feed primarily on zooplankton, small crustaceans, and other invertebrates, which they pursue by pursuit-diving from the surface.

The genus includes several species, such as the least auklet (Aethia pusilla), the crested auklet (Aethia cristatella), the whiskered auklet (Aethia pygmaea), and the parakeet auklet (Aethia psittacula). These species differ in crest development, plumage, and size, but share a similar ecological niche.

Breeding occurs on remote island colonies, where each species lays a single egg per season. Both parents typically participate in incubation and chick rearing, and nests may be in crevices, burrows, or on bare ledges. Auklets are highly colonial and undertake seasonal migrations, often moving offshore outside the breeding season.

Conservation status varies by species but overall Aethia populations face threats from habitat disturbance, oil spills, bycatch, and climate-driven changes in zooplankton communities. Several species are listed as of least concern, while others have more restricted ranges and require monitoring.