Wilson's storm petrel | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Procellariiformes |
Family: | Oceanitidae |
Genus: | Oceanites |
Species: | O. oceanicus |
Binomial name | |
Oceanites oceanicus (Kuhl, 1820) | |
Distribution range (blue) |
Wilson's storm petrel (Oceanites oceanicus), also known as Wilson's petrel, is a small seabird of the austral storm petrel family Oceanitidae. 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. The world population was estimated in 2022 as stable at 8 to 20 million birds. [2] In 2010 it had been estimated at 12-30 million. [3] A 1998 book had estimated more than 50 million pairs. [4] The name commemorates the Scottish-American ornithologist Alexander Wilson. The genus name Oceanites refers to the mythical Oceanids, the three thousand daughters of Tethys. The species name is from Latin oceanus, "ocean". [5]
Originally described in the genus Procellaria it has been placed under the genus Oceanites. Two or three subspecies are recognized and one population maorianus from New Zealand may be extinct. The nominate population breeds from Cape Horn to the Kerguelen Islands while exasperatus breeds along the Antarctic coast in the South Shetland and other islands. The population from Tierra del Fuego was described as chilensis (=wollastoni, magellanicus) but this is considered a nomen nudum although some authors have reinstated it, noting that it can be distinguished by white mottling on the belly. [6] [7]
The name Mother Carey's chicken was used in early literature and often applied to several petrel species while the generic name of stormy petrel referred to the idea that their appearance foretold stormy weather. F. M. Littler and others called it the yellow-webbed storm-petrel. [8]
Wilson's storm petrel is a small bird, 16–18.5 cm (6.3–7.3 in) in length with a 38–42 cm (15–16.5 in) wingspan. It is slightly larger than the European storm petrel and is essentially dark brown in all plumages, except for the white rump and flanks. The feet extend just beyond the square ended tail in flight. The European storm petrel has a very distinct whitish lining to the underwing and a nearly all dark upperwing. Wilson's storm petrel has a diffuse pale band along the upper wing coverts and lacks the distinctive white underwing lining. [9] The webbing between the toes is yellow with black spots in pre-breeding age individuals. [10] [11]
This species breeds on the Antarctic coastlines and nearby islands such as the South Shetland Islands during the summer of the southern hemisphere. It spends the rest of the year at sea, and moves into the northern oceans in the southern hemisphere's winter. It is much more common in the north Atlantic than the Pacific. Wilson's storm petrel is common off eastern North America in the northern summer and the seasonal abundance of this bird in suitable European waters has been revealed through pelagic boat trips, most notably in the area of the Isles of Scilly and Great Britain.
It is strictly pelagic outside the breeding season, and this, together with its remote breeding sites, makes Wilson's petrel a difficult bird to see from land. Only in severe storms might this species be pushed into headlands.
Wilson's storm petrel has a more direct gliding flight than other small petrels, and like most others it flies low over the seas surface and has the habit of pattering on the water surface as it picks planktonic food items from the ocean surface. Their unique fluttering and hovering flight is achieved often with their wings held high. Even in calm weather, they can make use of the slight breeze produced by the waves and in effect soar while using their feet to stabilize themselves. [12] Like the European storm petrel, it is highly gregarious, and will also follow ships and fishing boats. A soft peeping noise is often heard while the birds are feeding. They feed predominantly on planktonic invertebrates close to the surface, rarely plunging below the surface to capture prey. They may however sometimes take 3–8 cm long fish in the family Myctophidae. [13]
At 40 g on average, it is the smallest warm-blooded animal that breeds in the Antarctic region. [14] It nests in colonies close to the sea in rock crevices or small burrows in soft earth and lays a single white egg. Like most petrels, its walking ability is limited to a short shuffle to the burrow. In the Antarctic, nests may sometimes get snowed over leading to destruction of the nest or chicks. This storm petrel is strictly nocturnal at the breeding sites to avoid predation by larger gulls and skuas, and will even avoid coming to land on clear moonlit nights. Both parents tend the nest and feed the single chick. [15] The chicks call and beg for food, more vigorously when hungry. [16] Chicks remain at nest for about 60 days and are fed on krill, fish and amphipods. [17] Adults have the ability to identify their nest burrows [18] in the dark and their mates by olfactory cues. [19]
Population estimates in Antarctica evaluate the species to have about between 105 and 106 pairs. [20] Widespread throughout its large range, Wilson's storm petrel is evaluated as least concern on the IUCN Red List of Threatened Species. [1]
Procellariiformes is an order of seabirds that comprises four families: the albatrosses, the petrels and shearwaters, and two families of storm petrels. Formerly called Tubinares and still called tubenoses in English, procellariiforms are often referred to collectively as the petrels, a term that has been applied to all members of the order, or more commonly all the families except the albatrosses. They are almost exclusively pelagic, and have a cosmopolitan distribution across the world's oceans, with the highest diversity being around New Zealand.
Seabirds are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations. The first seabirds evolved in the Cretaceous period, and modern seabird families emerged in the Paleogene.
The black-browed albatross, also known as the black-browed mollymawk, is a large seabird of the albatross family Diomedeidae; it is the most widespread and common member of its family.
Northern storm petrels are seabirds in the genus Hydrobates in the family Hydrobatidae, part of the order Procellariiformes. The family was once lumped with the similar austral storm petrels in the combined storm petrels, but have been split, as they were not closely related. 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.
The family Procellariidae is a group of seabirds that comprises the fulmarine petrels, the gadfly petrels, the diving petrels, the prions, and the shearwaters. This family is part of the bird order Procellariiformes, which also includes the albatrosses and the storm petrels.
The European storm petrel, also known as British storm petrel, or just storm petrel, is a species of seabird in the northern storm petrel family, Hydrobatidae. The small, square-tailed bird is entirely black except for a broad, white rump and a white band on the under wings, and it has a fluttering, bat-like flight. The large majority of the population breeds on islands off the northern coasts of Europe, with the greatest numbers in the Faroe Islands, United Kingdom, Ireland, and Iceland. The Mediterranean population is a separate subspecies whose strongholds are Filfla Island (Malta), Sicily, and the Balearic Islands. This subspecies is indiscernible at sea from its Atlantic relatives.
The gentoo penguin is a penguin species in the genus Pygoscelis, most closely related to the Adélie penguin and the chinstrap penguin. The earliest scientific description was made in 1781 by Johann Reinhold Forster with a type locality in the Falkland Islands. The species calls in a variety of ways, but the most frequently heard is a loud trumpeting, which the bird emits with its head thrown back.
The New Zealand storm petrel is a small seabird of the family Oceanitidae endemic to New Zealand. Thought to be extinct since 1850, a series of sightings from 2003 to the present indicated the presence of a previously unknown colony. The population of New Zealand storm petrels has been estimated to be less than 2000.
The king penguin is the second largest species of penguin, smaller, but somewhat similar in appearance to the emperor penguin. There are two subspecies, A. p. patagonicus and A. p. halli; patagonicus is found in the South Atlantic and halli in the South Indian Ocean and at Macquarie Island.
The Antarctic petrel is a boldly marked dark brown and white petrel, found in Antarctica, most commonly in the Ross and Weddell Seas. They eat Antarctic krill, fish, and small squid. They feed while swimming but can dive from both the surface and the air.
The Chatham petrel or ranguru (Maori) is a medium-sized, grey, white and black gadfly petrel. It only breeds on the Chatham Islands, New Zealand, and until recently was restricted to the 218-hectare Rangatira or South-East Island.
East Antarctica, also called Greater Antarctica, constitutes the majority (two-thirds) of the Antarctic continent, lying primarily in the Eastern Hemisphere south of the Indian Ocean, and separated from West Antarctica by the Transantarctic Mountains. It is generally greater in elevation than West Antarctica, and includes the Gamburtsev Mountain Range in the center. The geographic South Pole is located within East Antarctica.
The grey-headed albatross also known as the gray-headed mollymawk, is a large seabird from the albatross family. It has a circumpolar distribution, nesting on isolated islands in the Southern Ocean and feeding at high latitudes, further south than any of the other mollymawks. Its name derives from its ashy-gray head, throat and upper neck.
The snow petrel is the only member of the genus Pagodroma. It is one of only three birds that have been seen at the Geographic South Pole, along with the Antarctic petrel and the south polar skua, which has the most southerly breeding sites of any bird, inland in Antarctica.
The Bonin petrel or nunulu is a seabird in the family Procellariidae. It is a small gadfly petrel that is found in the northwest Pacific Ocean. Its secretive habits, remote breeding colonies and limited range have resulted in few studies and many aspects of the species' biology are poorly known.
Austral storm petrels, or southern storm petrels, are seabirds in the family Oceanitidae, part of the order Procellariiformes. 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.
Kloa Point is a prominent coastal point projecting from the east side of Edward VIII Plateau, 5.6 kilometres (3 nmi) north of Cape Gotley, Antarctica. It was mapped by Norwegian cartographers from aerial photographs taken by the Lars Christensen Expedition, 1936–37, and called by them Kloa ('claw').