Puffinus opisthomelas
The Black-vented Shearwater (Puffinus opisthomelas) is a medium-sized seabird endemic to the productive waters of the California Current System, renowned for its distinctive flight and subtle but critical field marks. Measuring 30-38 cm (12-15 in) in length with a wingspan of 70-80 cm (28-31 in) and weighing around 300-500g, it presents a classic 'dark above, white below' shearwater pattern. Its upperparts are sooty brownish-black, contrasting with clean white underparts, but a key identifica...
This highly pelagic species primarily inhabits open ocean and coastal waters of the eastern Pacific. It breeds exclusively on offshore islands, utilizing rocky slopes and soft soils for burrow nesting.
Their diet consists mainly of small schooling fish such as anchovies, sardines, and mackerel, supplemented with squid and crustaceans. They forage by surface-seizing and shallow pursuit-diving.
Black-vented Shearwaters are colonial breeders, primarily active at their island colonies under the cover of darkness to avoid aerial predators, producing eerie, gurgling calls and cooing notes. At sea, they are diurnal foragers, often seen in large, active flocks, sometimes associating with othe...
The Black-vented Shearwater has a relatively restricted geographic distribution, centered entirely within the California Current System. Its breeding range is confined to a handful of offshore islands off the Pacific coast of Baja California, Mexico, including Natividad, San Benito, Cedros, and G...
Near Threatened
- The Black-vented Shearwater is almost entirely endemic to the California Current System, making it a unique avian indicator of this rich marine ecosystem. - Despite their common name, their undertail coverts are dark, a critical field mark to distinguish them from other 'black and white' shearw...