Justification Until 1998, there were only three records of this species since 1900, and none since 1959. Surveys have now found it to be more widespread and numerous than previously feared. The known population remains small, fragmented and probably declining, qualifying it as Vulnerable. However, the voice was only determined in 1998, and further surveys may find it with some regularity, potentially resulting in a future downlisting to Near Threatened.

Family/Sub-family Rallidae

Species name author King, 1828

Taxonomic source(s) SACC (2005 + updates), Sibley and Monroe (1990, 1993), Stotz et al. (1996)

Identification 20 cm. Small, boldly patterned rail. Buffy-brown upperparts streaked black. Pale slaty underparts with sides of breast washed brown. Black lower belly and vent barred white. White undertail-coverts. Red iris. Dusky red bill. Pinkish-red legs. Similar spp. Plumbeous Rail Pardirallus sanguinolentus is larger with longer, green bill, plain upperparts and unbarred rear. Other similarly patterned crakes are much smaller. Voice Series of 5-10 high-pitched and strident pí-ríc notes introduced by a single píc, also a loud call pi-choj (usually higher at the beginning) that seems to be a duet but it is performed by one bird, and a recently-described tri-ti-ti-ti-ti-ti¹¹.

Population estimate

Population trend

Range estimate (breeding/resident)

Country endemic?

2,500-9,999

decreasing

109,000 km²

No

Important Bird Areas Click here to view map showing IBAs where species is recorded and triggers any of the IBA criteria.

Ecology: It occurs in marshy Patagonian steppe wetlands^8,9, where there are large patches of dense and tall (c.2 m) rushbeds Schoenoplectus (Scirpus) californicus, and open areas, densely covered by Myriophyllum sp. and lush green grass^7,8. Some northerly post-breeding dispersal or possibly partial migration may occur, at least in southern populations⁸.

Threats The most serious threat is the planned development of intensive agriculture in suitable river valleys⁶. Intensive grazing of the steppes may have affected wetlands, because the resulting bare soil has been deposited in pools and marshes by the wind⁴. There has been extensive harvesting of aquatic vegetation for cattle⁴. However, this practice is now limited in many areas², and rushbeds at the site of the rediscovery (and presumably elsewhere) have increased in recent years owing to the particularly wet climate⁸. Water extraction for agriculture and other purposes may negatively impact on wetlands⁹.

Conservation measures underway Targeted surveys are responsible for recent records^7,8,9. One population lies adjacent to Los Glaciares National Park but, since cattle graze inside and outside the reserve, its extension would currently offer minimal protection⁹. Laguna Nimes municipal reserve offers some protection¹¹. In Chile, it occurs in Pali Aike and Torres del Paine National Parks^5,7, with extensive habitat remaining in the former⁵.

Conservation measures proposed Survey (with tape-playback) remaining main rivers and marshes throughout possible and historic range⁹. Protect key sites such as El Zurdo and Estancia Soledad. Ensure that agricultural development has minimal effects. Raise local awareness of the species and potential threats.

References Collar et al. (1992). 1. Blanco and Canevari (1992). 2. Blanco and Canevari (1995). 3. Carp (1991). 4. Fjeldså (1988). 5. Imberti and Mazar Barnett (1999). 6. S. Imberti in litt. (1999). 7. A. Jaramillo in litt. (2000). 8. Mazar Barnett et al. (1998b). 9. J. Mazar Barnett in litt. (2000, 2003). 10. M. Pearman in litt. (2003). 11. S. Imberti in litt. (2007).

Further web sources of information

Fully detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note, taxonomic treatment and IUCN Red List category may have changed since publication.

Recuento detallado de la especie tomado del libro Aves Amenazadas de las Americas, Libro Rojo de BirdLife International (BirdLife International 1992). Nota: la taxonomoía y la categoría de la Lista Roja de la UICN pudo haber cambiado desde esta publicación.

Text account compilers Phil Benstead (BirdLife International), David Capper (BirdLife International), Juan Mazar Barnett (Museo Argentino de Ciencias Naturales), John Pilgrim (BirdLife International), Andy Symes (BirdLife International)

Contributors Santiago Imberti, Alvaro P. Jaramillo, Juan Mazar Barnett (Museo Argentino de Ciencias Naturales), Mark Pearman

IUCN Red List evaluators Stuart Butchart (BirdLife International), Andy Symes (BirdLife International)

Recommended citation BirdLife International (2010) Species factsheet: Rallus antarcticus. Downloaded from http://www.birdlife.org on 30/7/2010

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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