Hydrobatidae – Northern Storm Petrels
The Hydrobatidae are otherwise known as Northern Storm petrels; they are seabirds, part of the order Procellariiformes. Two subfamilies were traditionally recognized. The Oceanitinae that are mostly found in southern waters (though the Wilson’s storm petrel regularly migrates into the northern hemisphere); there are seven species in five genera. The Hydrobatinae are the two genera Hydrobates and Oceanodroma. They are largely restricted to the northern hemisphere, although a few can visit or breed a short distance beyond the equator. Cytochrome b DNA sequence analysis suggests that the family is paraphyletic and so they are more accurately treated as distinct families.
These smallest of seabirds feed on planktonic crustaceans and small fish picked from the surface, typically while hovering. Their flight is fluttering and sometimes bat-like. They are strictly pelagic, coming to land only when breeding. In the case of most species, little is known of their behaviour and distribution at sea, where they can be hard to find and harder to identify. They are colonial nesters, displaying strong philopatry to their natal colonies and nesting sites. Most species nest in crevices or burrows and all but one species attend the breeding colonies nocturnally. Pairs form long-term monogamous bonds and share incubation and chick-feeding duties. Like many species of seabird, nesting is highly protracted with incubation taking up to 50 days and fledging another 70 days after that.
The diet of many storm petrels species is poorly known owing to difficulties in researching; overall the family is thought to concentrate on crustaceans. Small fish, oil droplets and molluscs are also taken by many species. Some species are known to be rather more specialised; the grey-backed storm petrel is known to concentrate on the larvae of goose barnacles. Almost all species forage in the pelagic zone. Although storm petrels are capable of swimming well and often form rafts on the water’s surface they do not feed on the water. Instead feeding usually takes place on the wing, with birds hovering above or “walking” on the surface (see morphology) and snatching small morsels. Rarely prey is obtained by making shallow dives under the surface.
There are, according to the IOC, 18 species of Northern Storm Petrels, which are:
European Storm Petrel Hydrobates pelagicus
Least Storm Petrel Oceanodroma microsoma
Wedge-rumped Storm Petrel Oceanodroma tethys
Band-rumped Storm Petrel Oceanodroma castro
Monteiro’s Storm Petrel Oceanodroma monteiroi
Cape Verde Storm Petrel Oceanodroma jabejabe
Swinhoe’s Storm Petrel Oceanodroma monorhis
Leach’s Storm Petrel Oceanodroma leucorhoa
Townsend’s Storm Petrel Oceanodroma socorroensis
Ainley’s Storm Petrel Oceanodroma cheimomnestes
Markham’s Storm Petrel Oceanodroma markhami
Tristram’s Storm Petrel Oceanodroma tristrami
Black Storm Petrel Oceanodroma melania
Guadalupe Storm Petrel Oceanodroma macrodactyla
Matsudaira’s Storm Petrel Oceanodroma matsudairae
Ashy Storm Petrel Oceanodroma homochroa
Hornby’s Storm Petrel Oceanodroma hornbyi
Fork-tailed Storm Petrel Oceanodroma furcata
Ashy Storm-petrel Oceanodroma homochroaSpecies AccountMedium-sized, dark-rumped storm-petrel with a long, deeply notched tail and grayish tones to the plumage. Usually flies fairly directly with light fluttering wingbeats; can be stronger in windy conditions.
Ashy Storm-petrel Oceanodroma homochroaSpecies AccountThe ashy storm petrel (Oceanodroma homochroa) is a small, scarce seabird of the storm petrel family Hydrobatidae. It breeds colonially on islands off the coasts of California and Mexico, and is one of six species of storm petrel that live and feed in the rich California Current system.
European Storm Petrel Hydrobates pelagicusSpecies AccountSound archive and distribution map.
European Storm Petrel Hydrobates pelagicusSpecies AccountThe European storm petrel, British storm petrel or just storm petrel (Hydrobates pelagicus) is a seabird in the storm petrel family, Hydrobatidae. It is the only member of the genus Hydrobates.
European Storm Petrel Hydrobates pelagicusRSPB Species AccountA little bigger than a sparrow it appears all black with a white rump. Its tail is not forked, unlike Leach's petrel.
Wilson's Storm Petrel Oceanites oceanicusSpecies AccountSound archive and distribution map.
Wilson's Storm Petrel Oceanites oceanicusSpecies AccountWilson's storm petrel (Oceanites oceanicus), also known as Wilson's petrel, is a small seabird of the storm petrel family. It is one of the most abundant bird species in the world and has a circumpolar distribution mainly in the seas of the southern hemisphere but extending northwards during the summer of the northern hemisphere.
Wilson's Storm Petrel Oceanites oceanicusCornell Species AccountOff the west coast of South America, the most through surveys are by Spear and Ainley (2007), who found two disjunct groups of this species, one in the central Pacific and the other in the Humboldt Current.
Number of bird species: 18
Albatrosses, Petrels and Shearwaters of the World| By Derek Onley & Paul Scofield | Christopher Helm | 2007 | Paperback | 240 pages, 46 colour plates, distribution maps | ISBN: 9780713643329 Buy this book from NHBS.com
Flight Identification of European Seabirds| By Anders Blomdahl, Bertil Breife & Niklas Holmstrom | Christopher Helm | 2007 | Paperback | 374 pages, 690 colour photos | ISBN: 9780713686166 Buy this book from NHBS.com
Petrels, Albatrosses & Storm-Petrels of North America| (A photographic guide) | by Steve NG Howell | Princeton University Press | 2012 | Hardback | 483 pages, 975 colour photos and colour illustrations, 66 colour distribution maps | ISBN: 9780691142111 Buy this book from NHBS.com
Seabirds| (An Identification Guide) | by Peter Harrison | Christopher Helm | 1991 | Hardback | 448 pages, 324 distribution maps, 88 colour plates, line drawings | ISBN: 9780713635102 Buy this book from NHBS.com
Seabirds| (a natural history) | by Anthony J Gaston | A&C Black | 2004 | Hardback | 222 pages, 22 colour plates, b/w photos, illustrations, figures | ISBN: 9780713665574 Buy this book from NHBS.com
Storm-petrels of the Eastern Pacific Ocean| (Species Assembly and Diversity along Marine Habitat Gradients) | by Larry B Spear & David G Ainley | American Ornithologists' Union | 2007 | Paperback | 77 pages, Figures, tables | ISBN: 9780943610719 Buy this book from NHBS.com