• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	C2a(ii)

Red List history

Year	Category	Criteria
2021	Vulnerable	C2a(ii)
2016	Vulnerable	C2a(i)
2013	Vulnerable	C2a(i)
2012	Vulnerable	C2a(i)
2008	Vulnerable	C2a(i)
2006	Vulnerable
2004	Vulnerable
2000	Vulnerable
1996	Critically Endangered
1994	Critically Endangered
1988	Threatened

Migratory status	unknown	Forest dependency	does not normally occur in forest
Land-mass type	continent	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	265,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	1000-9999, 2500-9999 mature individuals	medium	estimated	2014
Population trend	decreasing	poor	inferred	-
Generation length	1.99 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The species's population size is poorly known, but given that there were no documented records from 1959 to 1998, it is likely to be rare. It is fairly common at a handful of sites, with no known locality holding a population of more than c.35 individuals (Mazar Barnett et al. 1998, 2014, Imberti and Mazar Barnett 1999). Extensive surveys carried out between 1998 and 2006 at 58 wetlands distributed over an area of c.700,000 km² detected a maximum of 175 individuals in total, at 22 localities that collectively held approximately 85 km² of habitat (Mazar Barnett et al. 2014). Surveys in Santa Cruz in 2009-2013 detected at least one individual at each of two more localities (Roesler et al. 2014). Given the difficulty of detecting the species, there are likely to be undetected individuals. Nevertheless, the total population size is very unlikely to exceed 10,000 mature individuals, and could plausibly be less than 2,500 mature individuals (Mazar Barnett et al. 2014), so it is here placed in the band 1,000-9,999 mature individuals, with a best estimate in the range 2,500 - 9,999 mature individuals.

The subpopulation structure is poorly known, but a record of a vagrant individual in the Falkland Islands indicates that the species is able to disperse over large distances, so there is likely to be a degree of connectivity between habitat fragments. The population is therefore assumed to have a single subpopulation.

Trend justification: The species is threatened by continuing overgazing at some localities such as El Zurdo (A. de Miguel, I. Roesler and L. Fasola in litt. 2018), and by invasive American Mink Neovison vison, which is expanding its range (Mazar Barnett et al. 2014, Roesler et al. 2014, Fasola and Roesler 2016). Surveys in Santa Cruz found that the species's population density and site occupancy were negatively affected by the presence of mink (de Miguel et al. 2019). The species's range appears to have contracted considerably in the long-term, with no recent records from much of the known historical range. The species's population size is therefore inferred to be undergoing a continuing decline, the rate of which is unknown.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Argentina	extant	native	yes
Chile	extant	native	yes

Country/Territory	IBA Name
Argentina	El Zurdo
Argentina	La Angostura y Alto Río Chico
Argentina	Laguna Nimez y costa aledaña del Lago Argentino
Argentina	Parque Nacional Los Glaciares y adyacencias (Estancias El Sosiego, La Soledad y Anita)

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Grassland	Subtropical/Tropical Seasonally Wet/Flooded	major	resident
Wetlands (inland)	Bogs, Marshes, Swamps, Fens, Peatlands	major	resident
Wetlands (inland)	Freshwater Springs and Oases	suitable	resident
Wetlands (inland)	Permanent Freshwater Lakes (over 8ha)	major	resident
Wetlands (inland)	Permanent Freshwater Marshes/Pools (under 8ha)	major	resident
Wetlands (inland)	Permanent Rivers/Streams/Creeks (includes waterfalls)	major	resident
Altitude	0 - 570 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Agro-industry farming	Timing		Scope		Severity		Impact
		Future		Minority (<50%)		Rapid Declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Gathering terrestrial plants - Unintentional effects (species is not the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation
Energy production & mining	Renewable energy	Timing		Scope		Severity		Impact
		Future		Minority (<50%)		Very Rapid Declines		Low Impact: 5
		Stresses Ecosystem conversion, Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Neovison vison	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Reduced reproductive success, Species mortality
Natural system modifications	Dams & water management/use - Abstraction of ground water (agricultural use)	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation
Natural system modifications	Dams & water management/use - Small dams	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Natural system modifications	Fire & fire suppression - Increase in fire frequency/intensity	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Reduced reproductive success
Natural system modifications	Other ecosystem modifications	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion

---

Recommended citation
BirdLife International (2024) Species factsheet: Austral Rail Rallus antarcticus. Downloaded from https://datazone.birdlife.org/species/factsheet/austral-rail-rallus-antarcticus on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 22/12/2024.