The grey petrel (''Procellaria cinerea''), also called the brown petrel, pediunker or grey shearwater is a species of

seabird Seabirds (also known as marine birds) 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 enviro ...

in the

Procellariidae 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 (or tubenoses), which als ...

, or

petrel Petrels are tube-nosed seabirds in the bird order Procellariiformes. Description The common name does not indicate relationship beyond that point, as "petrels" occur in three of the four families within that group (all except the albatross f ...

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

. It is

pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...

and occurs in the open seas of the Southern Hemisphere, mainly between 32°S and 58°S.

Taxonomy

The grey petrel was formally described in 1789 by the German naturalist Johann Friedrich Gmelin under the binomial name ''Procellaria cinerea''. Gmelin's description was based on the "Cinereous fulmar" that had been described by the English ornithologist John Latham in 1785. The genus name is from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''procella'' meaning "storm" or "gale". The specific ''cinerea'' is from the Latin ''cinereus'' meaning "ash-grey" or "ash-coloured". The word ''petrel'' is derived from

Saint Peter ) (Simeon, Simon) , birth_date = , birth_place = Bethsaida, Gaulanitis, Syria, Roman Empire , death_date = Between AD 64–68 , death_place = probably Vatican Hill, Rome, Italia, Roman Empire , parents = John (or Jonah; Jona) , occupat ...

and the story of his walking on water. This is in reference to the petrels' habit of appearing to run on the water to take off.Gotch, A. T. (1995) The grey petrel is a member of the

, and the order

Procellariiformes Procellariiformes is an order (biology), order of seabirds that comprises four family (biology), families: the albatrosses, the Procellariidae, petrels and shearwaters, and two families of storm petrels. Formerly called Tubinares and still call ...

. As a member of the Procellariiformes, they share certain identifying features. First, they have nasal passages that attach to the upper bill called

naricorns A nostril (or naris , plural ''nares'' ) is either of the two orifices of the nose. They enable the entry and exit of air and other gasses through the nasal cavities. In birds and mammals, they contain branched bones or cartilages called tur ...

. Although the nostrils on the petrel are on top of the upper bill. The bills of Procellariiformes are also unique in that they are split into between seven and nine horny plates. They produce a stomach oil made up of

wax ester A wax ester (WE) is an ester of a fatty acid and a fatty alcohol. Wax esters comprise the main components of three commercially important waxes: carnauba wax, candelilla wax, and beeswax.. Wax esters are formed by combining one fatty acid with on ...

s and

triglycerides A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''tri-'' and ''glyceride''). Triglycerides are the main constituents of body fat in humans and other vertebrates, as we ...

that is stored in the

proventriculus The proventriculus is part of the digestive system of birds.Encarta World English Dictionary orth American Edition(2007). ''Proventriculus''. Source: (accessed: December 18, 2007) An analogous organ exists in invertebrates and insects. Birds Th ...

. This can be sprayed out of their mouths as a defence against predators and as an energy rich food source for chicks and for the adults during their long flights. Finally, they also have a

salt gland The salt gland is an organ for excreting excess salts. It is found in the cartilaginous fishes subclass elasmobranchii (sharks, rays, and skates), seabirds, and some reptiles. Salt glands can be found in the rectum of sharks. Birds and reptiles ...

that is situated above the nasal passage and helps desalinate their bodies, due to the high amount of ocean water that they imbibe. It excretes a high saline solution from their nose.Ehrlich, Paul R. (1988) Other English names include black-tailed shearwater or petrel, brown, bulky or great grey petrel, pediunker.

Description

The grey petrel is a large grey, white, and brown

. It averages in length, in wingspan and weighs around . It has a brownish-grey mantle, back, uppertail coverts, and upperwings. The belly is white and the underwings and under-tail that are ash-grey. It has a yellow-green

bill Bill(s) may refer to: Common meanings * Banknote, paper cash (especially in the United States) * Bill (law), a proposed law put before a legislature * Invoice, commercial document issued by a seller to a buyer * Bill, a bird or animal's beak Plac ...

and pink-grey feet.

Distribution and habitat

Grey petrels are

and typically stay between 32°S and 58°S during the non-breeding season. During the breeding season, they form

colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...

on several islands.

Antipodes Island In geography, the antipode () of any spot on Earth is the point on Earth's surface diametrically opposite to it. A pair of points ''antipodal'' () to each other are situated such that a straight line connecting the two would pass through Ear ...

, with an estimate of 53,000 pairs, and Gough Island with 10,000 pairs are the biggest colonies, with others on

Prince Edward Island Prince Edward Island (PEI; ) is one of the thirteen provinces and territories of Canada. It is the smallest province in terms of land area and population, but the most densely populated. The island has several nicknames: "Garden of the Gulf", ...

, Marion Island,

Tristan da Cunha Tristan da Cunha (), colloquially Tristan, is a remote group of volcanic islands in the South Atlantic Ocean. It is the most remote inhabited archipelago in the world, lying approximately from Cape Town in South Africa, from Saint Helena a ...

, Crozet Islands, Kerguelen Islands,

Amsterdam Island Amsterdam ( , , , lit. ''The Dam on the River Amstel'') is the capital and most populous city of the Netherlands, with The Hague being the seat of government. It has a population of 907,976 within the city proper, 1,558,755 in the urban area ...

, Campbell Island, and

Macquarie Island Macquarie Island is an island in the southwestern Pacific Ocean, about halfway between New Zealand and Antarctica. Regionally part of Oceania and politically a part of Tasmania, Australia, since 1900, it became a Tasmanian State Reserve in 197 ...

. They have an occurrence range of .BirdLife International (2021)

Behaviour

Breeding

Grey petrels breed on

, Gough Island, the

Prince Edward Islands The Prince Edward Islands are two small uninhabited islands in the sub-Antarctic Indian Ocean that are part of South Africa. The islands are named Marion Island (named after Marc-Joseph Marion du Fresne, 1724–1772) and Prince Edward Island ...

, Crozet Islands, Kerguelen Islands,

and on

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Campbell Campbell may refer to: People Surname * Campbell (surname), includes a list of people with surname Campbell Given name * Campbell Brown (footballer), an Australian rules footballer * Campbell Brown (journalist) (born 1968), American television ne ...

and

Antipodes Islands The Antipodes Islands ( Maōri: Moutere Mahue; "Abandoned island") are inhospitable and uninhabited volcanic islands in subantarctic waters to the south of – and territorially part of – New Zealand. The 21 km2 archipelago lies 860 ...

. They return to their breeding grounds in February and March and build a burrow for a nest. These burrows are on well-drained ground, often among '' Poa'' tussock grass, typically on steep terrain. By late March or early April, they lay their one

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the a ...

, with both birds incubating it. After hatching, the chick is cared for by both parents until it fledges between late September and early December.

Feeding

They dive from heights of up to in pursuit of food, which is primarily cephalopods.

Status and conservation

There is not a lot of recent information about this bird, but its population is believed to be shrinking slowly or possibly rapidly. Introduced

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s such as cats,

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model us ...

and

black Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white ...

rats are contributing to the decline, as well as

longline fishing Longline fishing, or longlining, is a commercial fishing angling technique that uses a long ''main line'' with fish bait, baited fish hook, hooks attached at intervals via short branch lines called ''snoods'' or ''gangions''.< ...

, which is a major problem. This bird is the most commonly caught bycatch by longline fisheries in

waters, with one estimate at 45,000 birds in the last 20 years. Other predators are the

weka The weka, also known as the Māori hen or woodhen (''Gallirallus australis'') is a flightless bird species of the rail family. It is endemic to New Zealand. It is the only extant member of the genus '' Gallirallus''. Four subspecies are recogni ...

and house mouse. To assist in maintaining or increasing its population, it has been placed on CMS Appendix II, and ACAP Annex1. Gough Island has been designated as a

World Heritage Site A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for h ...

has had preliminary work done to start long term monitoring, and in 2007 the monitoring started. In 2001, brown rats were eradicated from Campbell Island, and in 2006, SEAFO tightened longline fishing regulations. In the future, numerous tasks are planned, starting with a census on all the breeding locations. Also, studies on Gough Island pertaining to house mice, and finally, stricter fishing regulations enforced by

FAO The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...

RFMO A regional fishery body (RFB) is a type of international organization that is dedicated to the sustainability of fishery resources in a particular region, or of highly migratory species. An RFB is classified as one of the following two types: * reg ...

, and ACAP.

References

Sources

* * * * {{Authority control Procellaria Birds of the Indian Ocean Birds of subantarctic islands Fauna of Gough Island Birds described in 1789 Taxa named by Johann Friedrich Gmelin Fauna of the Prince Edward Islands Taxonomy articles created by Polbot