Puffinus and cold waters. These tubenose birds fly with stiff wings, and use a shearing flight technique to move across wave fronts with the minimum of active flight. Some small species, such as the Manx shearwater, are cruciform in flight, with their long wings held directly out from their bodies. Many are long-distance migrants, perhaps most spectacularly the sooty and short-tailed shearwaters, which perform migrations of 14,000 km or more each year. "Puffinus" shearwaters come to islands and coastal cliffs only to breed. They are nocturnal at the colonial breeding sites, preferring moonless nights to minimise predation. They nest in burrows
Black-vented shearwater 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. Black-vented shearwater The black-vented shearwater ("Puffinus opisthomelas")