Auklets are threatened by invasive species such as Norway rats (Rattus norvegicus) because of their high degree of coloniality and crevice-nesting.

The genus Aethia occurs only in the North Pacific and adjacent waters, mainly in the Bering Sea region.

[8] There are one or two fossil species which lived in the area of today's California during the Late Miocene: Aethia rossmoori Howard, 1968 (Monterrey Formation of Orange County), and an undescribed taxon tentatively placed in this genus.

[11] Auklets from the northern Bering Sea must move further south because of pack ice surrounding colonies during the winter.

[16] The auklets are mainly planktivores, eating a variety of calanoid copepods, euphausiids and other invertebrates such as jellyfish and ctenophores.

[2] Because they nest in crevices, auklets are vulnerable to predation by rats,[17] and have been extirpated from some islands that contained Arctic foxes introduced for farming.

[19] The large colony at Sirius Point, Kiska Island, Alaska (perhaps the largest auklet colony in the world[2]) experienced almost complete breeding failure in 2001 and 2002 because of rat predation and disturbance[20] and has been the focus of researchers at Memorial University of Newfoundland.