• 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
2018	Vulnerable	C2a(ii)
2016	Vulnerable	C2a(ii)
2012	Vulnerable	C2a(ii)
2010	Near Threatened	C2a(ii)
2008	Near Threatened	C2a(ii)
2006	Near Threatened
2004	Near Threatened
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Lower Risk/Least Concern

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	130,000 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	3400-3700 mature individuals	medium	estimated	2011
Population trend	decreasing	poor	inferred	2000-2010
Generation length	7.8 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: In 2003, S. Imberti (in litt. 2003) estimated that perhaps fewer than 5,000 individuals  remain. More recently, the total size of the breeding population has been calculated to lie between 3,428 and 3,673 adults (Agüero et al. 2011), and 1,899 juveniles were also counted, giving a total population of c.5,300-5,600 individuals, and 3,400-3,700 mature individuals.

Trend justification: The population is inferred to be experiencing a continuing decline owing to a decline in habitat quality, and probable decreases in survival and breeding success, as caused by human activities and other problematic species. The rate of decline has not been quantified.

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

Country/Territory	IBA Name
Argentina	Bahía Camarones y Norte del Golfo San Jorge

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Marine Coastal/Supratidal	Sea Cliffs and Rocky Offshore Islands	major	resident
Marine Intertidal	Rocky Shoreline	major	resident
Marine Intertidal	Tidepools	major	resident
Marine Neritic	Macroalgal/Kelp	major	resident
Marine Neritic	Seagrass (Submerged)	major	resident
Marine Neritic	Subtidal Loose Rock/pebble/gravel	major	resident
Marine Neritic	Subtidal Rock and Rocky Reefs	major	resident
Marine Neritic	Subtidal Sandy	major	resident
Marine Neritic	Subtidal Sandy-Mud	major	resident
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Biological resource use	Fishing & harvesting aquatic resources - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Reduced reproductive success
Energy production & mining	Oil & gas drilling	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance, Ecosystem degradation
Human intrusions & disturbance	Recreational activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Balanus glandula	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Carcinus maenas	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Larus dominicanus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Undaria pinnatifida	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects
Invasive and other problematic species, genes & diseases	Problematic native species/diseases - Larus dominicanus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses None
Invasive and other problematic species, genes & diseases	Problematic native species/diseases - Unspecified species	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Unknown		Unknown
		Stresses None
Pollution	Industrial & military effluents - Oil spills	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Reduced reproductive success, Species mortality

Purpose	Scale
Food - human	subsistence

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Recommended citation
BirdLife International (2024) Species factsheet: White-headed Steamerduck Tachyeres leucocephalus. Downloaded from https://datazone.birdlife.org/species/factsheet/white-headed-steamerduck-tachyeres-leucocephalus on 27/12/2024.
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 27/12/2024.