• 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.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2020	Least Concern
2018	Least Concern
2016	Least Concern
2012	Least Concern
2009	Least Concern
2008	Least Concern
2004	Least Concern
2000	Lower Risk/Least Concern
1994	Lower Risk/Least Concern
1988	Lower Risk/Least Concern

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	3,600,000 km2
Extent of Occurrence (non-breeding)	5,460,000 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	67000 mature individuals	poor	estimated	2015
Population trend	decreasing	-	suspected	-
Generation length	7.3 years	-	-	-

Population justification: The global population is estimated to number more than 100,000 individuals, which equates to more than 67,000 mature individuals (del Hoyo et al. 1996).

Trend justification: The population is suspected to be in decline owing to predation by invasive species and ongoing habitat destruction.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Japan	extant	native			yes
Russia	extant	native	yes		yes
Russia (Asian)	extant	native	yes		yes
USA	extant	native	yes		yes

Country/Territory	IBA Name
Russia (Asian)	Kuril islands (between Urup and Paramushir)
USA	Amchitka Pass 180W51N
USA	Buldir & Near Islands Marine
USA	Fenimore Pass & Atka Island Marine
USA	Gareloi Island Marine
USA	Kagamil Island Marine
USA	Kiska Island Marine
USA	Seguam Island Marine
USA	Unimak & Akutan Passes
USA	Buldir Island Colony
Russia (Asian)	Commander Islands
Russia (Asian)	Iony Island

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Marine Coastal/Supratidal	Sea Cliffs and Rocky Offshore Islands	major	breeding
Marine Intertidal	Rocky Shoreline	major	breeding
Marine Intertidal	Tidepools	major	breeding
Marine Neritic	Macroalgal/Kelp	major	resident
Marine Neritic	Pelagic	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
Marine Oceanic	Epipelagic (0-200m)	suitable	resident
Marine Oceanic	Mesopelagic (200-1000m)	suitable	resident
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Ecosystem degradation, Species mortality
Climate change & severe weather	Storms & flooding	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Reduced reproductive success, Species mortality

Purpose	Primary form used	Life stage used	Source	Scale	Level	Timing
Pets/display animals, horticulture	-	-		international	non-trivial	recent

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Recommended citation
BirdLife International (2023) Species factsheet: Aethia pygmaea. Downloaded from http://datazone.birdlife.org/species/factsheet/whiskered-auklet-aethia-pygmaea on 29/11/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 29/11/2023.