LC
Eastern Marsh-harrier Circus spilonotus



Taxonomy

Taxonomic note
Circus spilonotus and C. spilothorax (del Hoyo and Collar 2014) were previously lumped as C. spilonotus following Sibley and Monroe (1990, 1993).

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2021 Least Concern
2016 Least Concern
2014 Least Concern
Species attributes

Migratory status full migrant Forest dependency Does not normally occur in forest
Land mass type Average mass -
Distribution

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 7,180,000
Extent of Occurrence non-breeding (km2) 14,400,000
Number of locations -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 40000-60000 poor suspected 2001
Population trend Stable suspected -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations - - -
Percentage in largest subpopulation - - -
Generation length (yrs) 6.73 - - -

Population justification: Ferguson-Lees and Christie (2001) estimate the population at 20,000-30,000 pairs which equates to 40,000 to 60,000 mature individuals. The species is described as generally rare in Russia and uncommon in northern Japan (del Hoyo et al. 1992).

Trend justification: The population is suspected to be stable in the absence of evidence for any declines or substantial threats. Monitoring surveys of wintering birds at roosting sites in central Japan during 1994-2009 found that numbers fluctuated from year to year, but that the overall trend was fairly stable (Hirano et al. 2010).


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Bangladesh V Extant Yes
Brunei N Extant Yes
Cambodia N Extant Yes
China (mainland) N Extant Yes Yes
Cocos (Keeling) Islands (to Australia) N Extant Yes
Hong Kong (China) N Extant Yes
India V Extant Yes
Indonesia N Extant Yes
Iran, Islamic Republic of V Extant Yes
Japan N Extant Yes Yes
Laos N Extant Yes
Malaysia N Extant Yes
Mongolia N Extant Yes
Myanmar N Extant Yes
Northern Mariana Islands (to USA) V Extant
Philippines N Extant Yes
Russia N Extant Yes
Russia (Asian) N Extant Yes
Singapore N Extant Yes
South Korea N Extant Yes
Taiwan, China N Extant Yes
Thailand N Extant Yes
Vietnam N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Taiwan, China Tatu Rivermouth Wildlife Refuge

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Aquatic & Marine Artificial/Aquatic - Irrigated Land (includes irrigation channels) suitable resident
Artificial/Aquatic & Marine Artificial/Aquatic - Water Storage Areas (over 8ha) suitable resident
Artificial/Terrestrial Arable Land suitable resident
Grassland Subtropical/Tropical Seasonally Wet/Flooded suitable resident
Marine Intertidal Salt Marshes (Emergent Grasses) suitable resident
Wetlands (inland) Bogs, Marshes, Swamps, Fens, Peatlands major resident
Wetlands (inland) Permanent Freshwater Lakes (over 8ha) suitable resident
Wetlands (inland) Permanent Freshwater Marshes/Pools (under 8ha) major resident
Wetlands (inland) Permanent Inland Deltas suitable resident
Wetlands (inland) Seasonal/Intermittent/Irregular Rivers/Streams/Creeks suitable resident
Altitude 0 - 2000 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Hunting & trapping terrestrial animals - Unintentional effects (species is not the target) Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Species mortality
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Energy production & mining Mining & quarrying Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation
Energy production & mining Oil & gas drilling Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation
Natural system modifications Dams & water management/use - Abstraction of surface water (unknown use) Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Pollution Agricultural & forestry effluents - Type Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Primary form used Life stage used Source Scale Level Timing
Pets/display animals, horticulture - - Non-trivial Recent
Sport hunting/specimen collecting - - Non-trivial Recent

Recommended citation
BirdLife International (2022) Species factsheet: Circus spilonotus. Downloaded from http://www.birdlife.org on 26/06/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 26/06/2022.