The Atlantic petrel (''Pterodroma incerta'') is a

gadfly petrel The gadfly petrels or ''Pterodroma'' are a genus of about 35 species of petrels, part of the seabird order Procellariiformes. The gadfly petrels are named for their speedy weaving flight, as if evading gadflies (horseflies). The flight action is ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

to the South

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

. It breeds in enormous

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'' ...

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 ...

and Gough Island, and ranges at sea from

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

Namibia Namibia (, ), officially the Republic of Namibia, is a country in Southern Africa. Its western border is the Atlantic Ocean. It shares land borders with Zambia and Angola to the north, Botswana to the east and South Africa to the south and ea ...

, with most records at sea being to the west of the breeding islands, and along the subtropical convergence. Adults are about 43 cm long, powerful, large, stocky, dark in color with white belly. Their head can appear to be grey in worn plumage. Brown undercoating of wings and tail. These petrels can live on average of 15 years of age.

Population trends

Although the species exists in large numbers, the world population being estimated at around 5 million birds, it is listed as endangered by the IUCN. It is restricted to just two breeding islands and has declined historically due to exploitation for food. According to some studies, there are roughly 1.1 million mating pairs, but only about 25% of eggs survived. This is making their large population numbers decrease rapidly. Gough Island was the location of study, since other islands are inaccessible due to the steep cliffs. Due to reproduction mortality, this species can become locally extinct making their home range smaller.

Habitat and Ecology

The species feeds mostly on squid, which comprises 87% of its diet in some studies; it will also feed on

lanternfish Lanternfishes (or myctophids, from the Greek μυκτήρ ''myktḗr'', "nose" and ''ophis'', "serpent") are small mesopelagic fish of the large family Myctophidae. One of two families in the order Myctophiformes, the Myctophidae are represent ...

es (Myctophidae) as they ascend to the surface at night, as well as on

crustaceans Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean gro ...

and some fish. This species is known to being nocturnal habits when feeding. The nesting locations are between 50 and 300 meters above sea level, located on cliffsides on Gough Island and formerly, at

it was upwards of 700 meters. It nests in burrows dug in peaty soils in fern-bush vegetation.

Predators and threats

It is currently thought to be threatened by introduced

house mice The house mouse (''Mus musculus'') is a small mammal of the order Rodentia, characteristically having a pointed snout, large rounded ears, and a long and almost hairless tail. It is one of the most abundant species of the genus ''Mus''. Although ...

, which generally attack the chicks within a 2-hour period of hatching, leading to low breeding success. Another threat to the Atlantic petrel is

Hurricanes A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...

also known as a cyclone system, it has a severe impact on populations by displacing them from their habitat and breeding grounds. Feather mites, Microspalax atlanticus, are affecting the bird's population on the

ian coast. This species of mites is affecting a variety of wild birds in Brazil, but it has a large impact on the Atlantic petrel. Many birds died of starvation due to their food source like squid being altered from the intense

hurricanes A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...

. This is another leading threat to their decline in population. Significant mortality rate is increasing as the storms intensities increase, largely in females.

Conservation Efforts

Starting around the 1970s, on

, they have programs to teach and learn about this species and why it is important for the ecosystem. They also educate about the dangers that the birds are facing and research ways to implement protection for them in the future. Considering their populations numbers are high, their declining population is thought to be due to the mortality rate of eggs and young. Gough Island is a nature reserve and World Heritage site, there is a field station on this island to observe the Atlantic Petrels population. Research on the House mouse is important to finding ways in reducing these predators' effect on the

Atlantic Petrel The Atlantic petrel (''Pterodroma incerta'') is a gadfly petrel endemic to the South Atlantic Ocean. It breeds in enormous colonies on Tristan da Cunha and Gough Island, and ranges at sea from Brazil to Namibia, with most records at sea bein ...

Actions Proposed

Further studies on the House mouse and find ways to eradicate mice on Gough Island. Minimize the risk of introducing other species that are invasive to Gough Island and find methods better to understand this species on their habits. Use measures of demographic mapping to better understand the island along with population trends. It was formerly classified as a

vulnerable species A vulnerable species is a species which has been categorized by the International Union for Conservation of Nature as being threatened with extinction unless the circumstances that are threatening its survival and reproduction improve. Vulnera ...

by the IUCN. However, new research demonstrated the severe impact of predation by mice. Consequently, it was uplisted to

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and in ...

status in 2008.BLI (2008a,b)

Footnotes

References

* BirdLife International (BLI) (2008a)
2008 IUCN Redlist status changes.
Retrieved 2008-MAY-23. * BirdLife International (BLI) (2008b)
Atlantic Petrel Species Factsheet
Retrieved 2008-MAY-23. * Enticott, J.W. (1991): Distribution of the Atlantic Petrel ''Pterodroma incerta'' at sea. ''Marine Ornithology'' 19(1): 49–60
PDF fulltext
* Klages, N.T.W. & Cooper, J. (1997) Diet of the Atlantic Petrel ''Pterodroma incerta'' during breeding season at South Atlantic Gough Island. ''Marine Ornithology'' 25(1+2): 13–16
PDF fulltext
{{Taxonbar, from=Q780365 Gadfly petrels Pterodroma Birds of the Atlantic Ocean Birds of Argentina Birds of Brazil Fauna of Gough Island Birds of Southern Africa Birds of islands of the Atlantic Ocean Birds of subantarctic islands Birds of Uruguay Endangered fauna of Africa Endangered fauna of South America Birds described in 1863 Species endangered by invasive species