The austral rail (''Rallus antarcticus'') is a

Vulnerable species A vulnerable species is a species which has been Conservation status, categorized by the International Union for Conservation of Nature as being threatened species, threatened with extinction unless the circumstances that are threatened species, ...

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

in subfamily Rallinae of family

Rallidae Rails (avian family Rallidae) are a large, Cosmopolitan distribution, cosmopolitan family (biology), family of small- to medium-sized terrestrial and/or semi-amphibious birds. The family exhibits considerable diversity in its forms, and includes ...

, the rails, gallinules, and coots. It is found in

Argentina Argentina, officially the Argentine Republic, is a country in the southern half of South America. It covers an area of , making it the List of South American countries by area, second-largest country in South America after Brazil, the fourt ...

and

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

.HBW and BirdLife International (2021) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 6. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v6_Dec21.zip retrieved August 7, 2022

Taxonomy and systematics

Some authors have considered the austral rail as

conspecific Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species. Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organism ...

with the

Virginia rail The Virginia rail (''Rallus limicola'') is a small waterbird, of the family Rallidae. These birds remain fairly common despite continuing loss of habitat, but are secretive by nature and more often heard than seen. They are also considered a gam ...

(''R. limicola'') but their treatment has not been widely accepted. The species is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

.Clements, J. F., T. S. Schulenberg, M. J. Iliff, T. A. Fredericks, J. A. Gerbracht, D. Lepage, S. M. Billerman, B. L. Sullivan, and C. L. Wood. 2022. The eBird/Clements checklist of birds of the world: v2022. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ retrieved November 10, 2022Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 July 2022. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved July 24, 2022

Description

The austral rail is about long. Adults have dull brown upperparts with buff-edged black centers to the back feathers. Their face and throat are gray, their breast olive brown, and their flanks barred with black and white. Juveniles are similar with the addition of sooty tips on the breast feathers and a white throat.Taylor, B., P. F. D. Boesman, E. de Juana, and C. J. Sharpe (2020). Austral Rail (''Rallus antarcticus''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.ausrai1.01 retrieved November 23, 2022

Distribution and habitat

The austral rail is patchily distributed in southern Chile's

Magallanes Region The Magallanes Region (), officially the Magallanes y la Antártica Chilena Region () or Magallanes and the Chilean Antarctica Region in English, is one of Chile's 16 first order administrative divisions. It is the southernmost, largest, and sec ...

and in southern Argentina between the departments of Río Negro and Santa Cruz. It formerly occurred as far north as

Santiago Santiago (, ; ), also known as Santiago de Chile (), is the capital and largest city of Chile and one of the largest cities in the Americas. It is located in the country's central valley and is the center of the Santiago Metropolitan Regi ...

, Chile, and

Buenos Aires Buenos Aires, controlled by the government of the Autonomous City of Buenos Aires, is the Capital city, capital and largest city of Argentina. It is located on the southwest of the Río de la Plata. Buenos Aires is classified as an Alpha− glob ...

, Argentina. It has also been recorded as a

vagrant Vagrancy is the condition of wandering homelessness without regular employment or income. Vagrants usually live in poverty and support themselves by travelling while engaging in begging, scavenging, or petty theft. In Western countries, ...

on the

Falkland Islands The Falkland Islands (; ), commonly referred to as The Falklands, is an archipelago in the South Atlantic Ocean on the Patagonian Shelf. The principal islands are about east of South America's southern Patagonian coast and from Cape Dub ...

. It is found mostly near the coast where it inhabits wet fields and meadows, rushy lake shores, and reedbeds.Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 July 2022. Species Lists of Birds for South American Countries and Territories. https://www.museum.lsu.edu/~Remsen/SACCCountryLists.htm retrieved July 24, 2022

Behavior

Movement

Some of the southernmost populations appear to move north during the austral autumn.

Feeding

Little is known about the austral rail's foraging behavior and diet. Both are assumed to be similar to that of the Ecuadorian rail (''R. aequatorialis''), which has an eclectic diet.Conway, C. J. (2020). Virginia Rail (''Rallus limicola''), version 1.0. In Birds of the World (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.virrai.01 retrieved November 23, 2022

Breeding

The austral rail's breeding biology is almost unknown. It appears to breed during October and November in Chile and November in Argentina. What is thought to be its nest was on the ground under a bramble; it was a depression in the ground lined with grass and rushes and held eight eggs.

Vocalization

The austral rail's main vocalization is "a series of high-pitched notes 'pee', 'peeree', 'peek' etc." which is often given in duet. It also makes "low booming sounds or grunts" and "a rather drawn-out single squeal."

Status

The

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

originally assessed the austral rail in 1988 as Threatened, then in 1994 as Critically Endangered, and since 2000 as Vulnerable. There were no documented records between 1959 and 1998 and is currently known from a limited number of locations. It has an estimated population of between 2500 and 10,000 mature individuals though the number might be as low as 1000, and the population is believed to be declining. The principal threat is grazing in its habitat but water diversion and introduced American mink (''Neogale vison'') also contribute to its decline. It is found in five formally protected areas and some de facto protected private lands.

References

{{Taxonbar, from=Q666847 Rallus Birds described in 1828 Taxonomy articles created by Polbot