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

Taxonomic note
This new species was described by Melo et al. (2022). It differs from congeners most conspicuously in its distinctive call, which is most similar to that of the widely allopatric O. ireneae. Monotypic.

Taxonomic source(s)
Handbook of the Birds of the World and BirdLife International. 2023. Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world. Version 8. Available at: https://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v8_Dec23.zip.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
B1ab(iii)	B1ab(iii)+2ab(iii)	B1ab(iii)+2ab(iii); D1+2

Red List history

Year	Category	Criteria
2023	Critically Endangered	B1ab(iii)
2016	Not Recognised
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	does not normally occur in forest
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	64 km2
Area of Occupancy (breeding/resident)	64 km2
Number of locations	1	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	813-2533,1149-1597 mature individuals	good	estimated	2019
Population trend	decreasing	-	suspected	-
Generation length	3.7 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The population has been estimated using distance sampling based on point counts detecting calling individuals (assumed to be mature) during the short dry season which is assumed to be the breeding season (Freitas et al. 2022). Two models performed similarly but resulted in distinct estimates, hence both were used resulting in densities of either 33.4 individuals/km² (95% CI: 23.6-47.2) or 46.4 individuals/km² (29.3-73.6) and population estimates of 1,149 individuals (813-1,623) or 1,597 individuals (1,007-2,533) (Freitas et al. 2022). It is noted that this estimate is based on the probable occurrence of the species to the highest elevations: if the elevation is restricted to below 500 m Freitas et al. (2022) indicate the population size would be 200 individuals smaller.

Trend justification: There is no data to estimate the population trend, but it is suspected to be declining based on the inferred continuing decline in the area, extent and quality of habitat.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
São Tomé e Príncipe	extant	native	yes

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	suitable	resident
Altitude	50 - 500 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Biological resource use	Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species disturbance, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Cercopithecus mona	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus rattus	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Negligible declines		Medium Impact: 6
		Stresses Reduced reproductive success
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Future		Minority (<50%)		Rapid Declines		Low Impact: 4
		Stresses Ecosystem degradation, Ecosystem conversion

---

Recommended citation
BirdLife International (2024) Species factsheet: Principe Scops-owl Otus bikegila. Downloaded from https://datazone.birdlife.org/species/factsheet/principe-scops-owl-otus-bikegila 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.