The ashy storm-petrel is a small, grayish-brown nocturnal seabird. Its breeding range is limited to rocks and small islands off the coast of California, and northern Baja California, Mexico. Some experts estimate that there are only about 5,000-10,000 breeding ashy storm-petrels. Nearly half the world population breeds on the South Farallon Islands. The remainder nest on the Channel Islands off southern California and other small rocks and islands along the coast. They spend most of their time far at sea where they feed on small fish and invertebrates. Because of their secretive nature, they are rarely seen on land. However, in the fall months they congregate in large flocks at sea which are a favorite sight of ocean birdwatching trips.

Because of its small world population and the numerous threats it faces, the species is listed as Endangered by the International Union for Conservation of Nature (IUCN). The U.S. Fish & Wildlife Service has identified the ashy storm-petrel as a Bird Species of Conservation Concern and it is listed as a Bird Species of Conservation Concern by the California Department of Fish and Wildlife. Taking measures to reduce risks to the ashy storm-petrel population, such as mouse eradication on the South Farallon Islands, is expected to help keep the rare, threatened bird off the federal Endangered Species list.