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

Taxonomic note

Ninox philippensis, N. spilocephala, N. leventisi, N. reyi, N. rumseyi, N. spilonotus and N. mindorensis (del Hoyo and Collar 2014) were previously lumped as N. philippensis 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.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	C2a(i)	C2a(i); D1

Red List history

Year	Category	Criteria
2017	Endangered	C2a(i)
2016	Vulnerable	C2a(i)
2014	Vulnerable	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)	3,500 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	250-999 mature individuals	poor	estimated	2017
Population trend	decreasing	-	suspected	-
Generation length	4.1 years	-	-	-

Population justification: The global population estimate was previously estimated at 1,000-2,499 mature individuals, however it has been suggested that each island may only contain 100-200 mature individuals given the amount of cover on the islands (R. Hutchinson in litt. 2016). Congeners have been reported to have range sizes up to 206 or even 307 ha (Olsen et al. 2011, Pryde and Green 2016), and bird density can be low on Sibuyan (D. Allen in litt. 2013). Therefore, it is plausible that sub-population sizes may be this low. As such, the overall population size would be <500 mature individuals, and so would fall into the range of 250-999 mature individuals, with <250 mature individuals per sub-population.

Trend justification: This species's population is suspected to be in decline owing to continued deforestation, driven by the expansion of agriculture, clearance for livestock, logging and mining.

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Subtropical/Tropical Heavily Degraded Former Forest	suitable	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Altitude	0 - 1000 m	Occasional altitudinal limits

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%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Small-holder grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Energy production & mining	Mining & quarrying	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Rapid Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion

Purpose	Scale
Pets/display animals, horticulture	international

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Recommended citation
BirdLife International (2024) Species factsheet: Romblon Boobook Ninox spilonotus. Downloaded from https://datazone.birdlife.org/species/factsheet/romblon-boobook-ninox-spilonotus on 22/12/2024.
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 22/12/2024.