Black-vented shearwater Black-vented shearwater The black-vented shearwater ("Puffinus opisthomelas") is a species of seabird. The bird is 30–38 cm in size, with a 76–89 cm wingspan. Formerly considered a subspecies of the Manx shearwater, its actual 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 sometimes can be seen from shore. It predominantly nests on offshore islands off north and western Baja California, namely Isla de Guadalupe, Islas San Benito and Isla Natividad. It is fairly common off the United States coast of
Bulweria "b" sequence analysis has proven them to be closely related to the shearwaters in the genus "Puffinus" and especially the "Procellaria" petrels. Bulweria Bulweria is a genus of seabirds in the family Procellariidae named after English naturalist James Bulwer. The genus has two extant species, Bulwer's petrel ("B. bulwerii") and Jouanin's petrel ("B. fallax"). A third species, the Olson's petrel ("Bulweria bifax"), became extinct in the early 16th century; it is known only from skeletal remains. Bulwer's Petrel ranges in the Atlantic, Indian and Pacific Oceans, whereas Joaunin's Petrel is confined to the northwestern Indian Ocean. Olson's Petrel is known