The crested auklet (Aethia cristatella) is a small seabird of the family Alcidae, distributed throughout the northern Pacific and the Bering Sea. The species feeds by diving in deep waters, eating krill and a variety of small marine animals. It nests in dense colonies of up to 1 million individuals in the Bering Sea and the Sea of Okhotsk. It often breeds in mixed-species colonies with the least auklet, a smaller congener.
The species is known for its sexual ornaments, found in both males and females. These include colorful plumage with a forehead crest, a striking scent recalling citrus fruit, and a loud trumpet call, all of which appear to have evolved through sexual selection. The total population is around 6 million, almost half in North America. It is in general considered to be of least concern, though the Alaskan population faces additional threats from predation and oil spills.