Black-vented shearwater

The black-vented shearwater (Puffinus opisthomelas) is a species of seabird. The bird is 30–38 cm in length with a 76–89 cm wingspan. Formerly considered a subspecies of the Manx shearwater, its actual taxonomic relationships are unresolved.

This species is pelagic, occurring in the Pacific Ocean and the Gulf of California. It comes closer to land than most other shearwaters, so it can sometimes be seen from shore. It nests predominantly on offshore islands off north and western Baja California, namely Isla Natividad (ca. 95% of the nesting population), Isla de Guadalupe, and Islas San Benito. It is fairly common off the United States coast of central and southern California during the country's colder months.

The black-vented shearwater is thought to feed on mainly small fish. This bird nests in burrows and caves; it is a colonial nester.

In the past, this bird had been threatened by feral cats and other predators on its breeding islands, but the problem seems to have been largely eliminated. There is some loss of birds from commercial gill netting, and the species is classified as near threatened by the IUCN mainly due to the uncertain impact on it by the expanding fishing industry.