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

Taxonomic note
Bubo blakistoni (del Hoyo and Collar 2014) was previously placed in the genus Ketupa.

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. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	C2a(i)	A2cd+3cd+4cd;C2a(i)

Red List history

Year	Category	Criteria
2016	Endangered	C2a(i)
2013	Endangered	C2a(i)
2012	Endangered	C2a(i)
2008	Endangered	C2a(i)
2005	Endangered
2004	Endangered
2000	Endangered
1996	Endangered
1994	Endangered
1988	Threatened

Migratory status	not a migrant	Forest dependency	high
Land-mass type	continent shelf island	Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	5,220,000 km2	medium
Number of locations	11-100	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	1000-2499 mature individuals	medium	estimated	2000
Population trend	decreasing	poor	suspected	1998-2008
Rate of change over the past 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Generation length	5.7 years	-	-	-
Number of subpopulations	2-100	-	-	-

Population justification: The global population is estimated to number a few thousand birds, based on estimates of 250-400 in Primorye alone [or up to 80 pairs] (J. Slaght in litt. 2012). It is precautionarily placed in the band 1,000-2,499 mature individuals, equating to 1,500-3,749 individuals in total, rounded here to 1,500-4,000 individuals. The total population size in Japan is 140 individuals (Hayashi in litt. 2016). Surveys throughout its range are required to gain a more accurate estimate than this.

Trend justification: A number of threats exist which impact negatively upon this species, owing to its requirement for clean, stocked, relatively undisturbed waterways. Hence it is suspected to be declining rapidly.

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

Country/Territory	IBA Name
China (mainland)	Dashanzuizi
China (mainland)	Liangshui Nature Reserve
China (mainland)	Nanweng He Nature Reserve
China (mainland)	Xunbiela He Nature Reserve
Japan	Shiretoko, Mount Syari-dake
Russia (Asian)	Inya valley
Russia (Asian)	Lesser Kuril Ridge and Kunashir Island
Russia (Asian)	Middle reaches of the Bikin river
Russia (Asian)	Middle reaches of the Iman river
Russia (Asian)	Mukhtel' lake
Russia (Asian)	Udyl' lake

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	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		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
		Ongoing		Majority (50-90%)		Rapid Declines		Medium Impact: 7
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Marine & freshwater aquaculture - Industrial aquaculture	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species mortality
Biological resource use	Fishing & harvesting aquatic resources - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Indirect ecosystem effects
Biological resource use	Fishing & harvesting aquatic resources - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species mortality
Biological resource use	Logging & wood harvesting - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Rapid Declines		Medium Impact: 7
		Stresses Ecosystem degradation, Inbreeding
Human intrusions & disturbance	Work & other activities	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species disturbance
Natural system modifications	Dams & water management/use - Dams (size unknown)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem conversion
Pollution	Industrial & military effluents - Type Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Transportation & service corridors	Roads & railroads	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species mortality
Transportation & service corridors	Utility & service lines	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Blakiston's Eagle-owl Bubo blakistoni. Downloaded from https://datazone.birdlife.org/species/factsheet/blakistons-eagle-owl-bubo-blakistoni on 18/12/2024.
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 18/12/2024.