Alcidae

Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the murres, guillemots, auklets, puffins, and murrelets. The family contains 25 extant or recently extinct species that are classified into 11 genera. Auks are found throughout the Northern Hemisphere.

species of bird

Aethia is a genus of four small (85–300g) auklets endemic to the North Pacific Ocean, Bering Sea and Sea of Okhotsk and among some of North America's most abundant seabirds. The relationships between the four true auklets remains unclear. Auklets are threatened by invasive species such as Norway rats (Rattus norvegicus) because of their high degree of coloniality and crevice-nesting.

thumb|right|Common guillemots, one in bridled form (with "spectacles"), and one [[Brünnich's guillemot (U. lomvia, with white-marked bills) from the genus Uria]] thumb|right|Black guillemot (C. grylle icelandicus) thumb|right|Common guillemot in bridled form, a white circle around the eye with an extension backwards suggesting they are wearing spectacles

Cerorhinca is a genus of auk containing the rhinoceros auklet and several fossil species.