EN
Romblon Boobook Ninox spilonotus



Taxonomy

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.

IUCN Red list criteria met and history
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)
Species attributes

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

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 3,500
Number of locations -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 250-999 poor estimated 2017
Population trend Decreasing 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) 4.1 - - -

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 distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Philippines N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name

Habitats & altitude
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  

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%) 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

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

Recommended citation
BirdLife International (2021) Species factsheet: Ninox spilonotus. Downloaded from http://www.birdlife.org on 09/12/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 09/12/2021.