• 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., 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
2020	Least Concern
2016	Near Threatened	B1ab(iii)
2012	Near Threatened	B1ab(iii)
2008	Near Threatened	B1a+b(iii)
2004	Near Threatened
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Lower Risk/Least Concern

Migratory status	not a migrant	Forest dependency	medium
Land-mass type	shelf island	Average mass	6 g

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	31,600 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	15000-24999 mature individuals	poor	suspected	2020
Population trend	stable	-	suspected	-
Generation length	2.4 years	-	-	-

Population justification: The species is described as fairly common within its small range (Cheke et al. 2001). Assuming that it occurs at similar densities to a congener, Lovely Sunbird (Aethopyga shelleyi), at 49.1 individuals/km² (Santini et al. 2018), with 10% of the mapped range likely occupied, the population may thus number 37,000 individuals, roughly equating to 25,000 mature individuals. However, the species is thought to occur at lower densities than congeners across its suitable habitat (P. Simpson in litt. 2020). Assuming that this value is a maximum therefore, the population is tentatively placed in the band of 15,000-24,999 mature individuals.

Trend justification: Forests within the range of the species are not thought to be under imminent threat. Recent fores loss estimates remain low at <5% (Tracewski et al. 2016, Global Forest Watch 2020) over a 3-generation period (10 years; Bird et al. 2020). The population is therefore suspected to be stable in the absence of evidence for any substantial declines or threats.

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

Country/Territory	IBA Name
Philippines	Mount Agtuuganon and Mount Pasian
Philippines	Mount Apo
Philippines	Mount Busa-Kiamba
Philippines	Mount Kitanglad
Philippines	Mount Malindang

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Shrubland	Subtropical/Tropical High Altitude	suitable	resident
Altitude	1500 - 0 m	Occasional altitudinal limits	823 - 2000 m

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%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Apo Sunbird Aethopyga boltoni. Downloaded from https://datazone.birdlife.org/species/factsheet/apo-sunbird-aethopyga-boltoni on 22/11/2024.
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 22/11/2024.