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

Taxonomic note
Irham et al. (2022) describe a new blue-flycatcher from the Meratus mountains of SE Borneo. It is most closely related to Cyornis montanus but morphologically distinguished in males by being lighter blue on the upperparts and more whitish and less reddish on the underparts. Female C. kadayangensis has a white belly, whereas female C. montanus differs distinctly in its all-reddish underparts (down to vent). It also differs genetically and vocally. Monotypic.

Taxonomic source(s)
Handbook of the Birds of the World and BirdLife International. 2022. Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 7. Available at: https://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v7_Dec22.zip.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2022	Near Threatened	B1b(iii)
2016	Not Recognised
2012	Not Recognised
2008	Not Recognised
2004	Not Recognised
2000	Not Recognised
1994	Not Recognised
1988	Not Recognised

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	15,500 km2
Area of Occupancy (breeding/resident)	3,100 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	-	-	-
Population trend	decreasing	-	suspected	-
Generation length	2.62 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The population size of this species has not been estimated, although it has consistently been described as locally common (Eaton et al. 2016, Eaton et al. 2021, Irham et al. 2022).

Trend justification: There are no accurate trend data available for this species, although it is suspected of declining. Forest loss in this species' mapped range has been equivalent to c.5-7% over the past ten years (Global Forest Watch 2022, using data from Hansen et al. [2013] and methods disclosed therein). This species is thought to be moderately forest dependent. Although it has been recorded in forest mixed with rubber plantations, some forest loss, especially at the lowest limits of its elevational range, has amounted to total clearance for agriculture that is suspected of causing the loss of some territories. In 2022, this species was recorded in an Indonesian songbird market for the first time (P. Akbar in litt. 2022). The scale and impacts of this as a threat remain to be determined, but it is noteworthy that demand for other Cyornis in Indonesia (e.g. C. banyumas) has driven very rapid population declines which should be monitored in this species.

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Plantations	suitable	resident
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	900 - 1300 m	Occasional altitudinal limits	(min) 500 m

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Shifting agriculture	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
Agriculture & aquaculture	Wood & pulp plantations - Small-holder plantations	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Species mortality

Purpose	Scale
Pets/display animals, horticulture	subsistence, national

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Recommended citation
BirdLife International (2024) Species factsheet: Meratus Blue Flycatcher Cyornis kadayangensis. Downloaded from https://datazone.birdlife.org/species/factsheet/meratus-blue-flycatcher-cyornis-kadayangensis on 03/12/2024.
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 03/12/2024.