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

Taxonomic note
Cyornis herioti and C. camarienensis (del Hoyo and Collar 2016) were previously lumped as C. herioti following Sibley and Monroe (1990, 1993).

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2016	Near Threatened	C2a(i)
2012	Not Recognised
2008	Not Recognised
2004	Not Recognised
2000	Not Recognised
1994	Not Recognised
1988	Not Recognised

Migratory status	not a migrant	Forest dependency	medium
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	119,000 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	10000-19999 mature individuals	poor	suspected	2016
Population trend	decreasing	-	suspected	-
Generation length	3.2 years	-	-	-

Population justification: Based on known records, low population density estimates for closely related species and assuming only a proportion of its range is occupied, this species likely has a population size of >10,000 mature individuals, with >1,000 mature individuals in each subpopulation. However, the global population size may approach this threshold value and so the population size is tentatively placed in the range of 10,000-19,999 mature individuals.

Trend justification: The population is suspected to be in decline owing to ongoing habitat destruction.

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

Country/Territory	IBA Name
Philippines	Central Sierra Madre mountains
Philippines	Kalbario-Patapat National Park
Philippines	Mount Makiling
Philippines	North Eastern Cagayan Protected Landscape and Seascape
Philippines	Northern Sierra Madre Natural Park
Philippines	Peñablanca Protected Landscape and Seascape
Philippines	Quezon National Park

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Mangrove Vegetation Above High Tide Level	suitable	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Altitude	100 - 1200 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
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Energy production & mining	Mining & quarrying	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Blue-breasted Blue Flycatcher Cyornis herioti. Downloaded from https://datazone.birdlife.org/species/factsheet/blue-breasted-blue-flycatcher-cyornis-herioti on 19/12/2024.
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 19/12/2024.