• 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. 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.
Rasmussen, P. C. 1998. A new scops-owl from Great Nicobar Island. Bulletin of the British Ornithologists' Club 118: 141-153.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2019	Near Threatened	C2a(i)
2018	Near Threatened	C2a(i)
2016	Data Deficient
2012	Data Deficient
2008	Data Deficient
2004	Data Deficient
2000	Data Deficient
1994	Not Recognised
1988	Not Recognised

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	2,800 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	2500-9999 mature individuals	poor	estimated	2017
Population trend	decreasing	-	inferred	2014-2025
Rate of change over the past 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	1-9%	-	-	-
Generation length	3.7 years	-	-	-

Population justification: The species is described as common, particularly on Great Nicobar (P. Singh per Rasmussen and Anderton 2012, S. Dalvi per P. Rasmussen in litt. 2016). Using high population density estimates for congeners, and assuming that only a proportion of its range is occupied, would give a population size of 3,200 mature individuals for Great Nicobar. Due to the uncertainty in the estimate, this, the largest subpopulation may actually be smaller than this, such that it may be as few as 1,000 mature individuals. The species has been found on Teressa Island and may occur on further islands in the Nicobar group, although some of the more northerly islands have been surveyed and the species has not been found. Therefore, the global population size may be best placed in the range of 2,500-9,999 mature individuals.

Trend justification: The population is potentially declining as a consequence of slow rates of habitat loss (per Tracewski et al. 2016) as well as anthropogenic impacts like hunting and snaring or the use of pesticides (S. Pande in litt. 2016).

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	suitable	resident
Altitude		Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Agro-industry farming	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Annual & perennial non-timber crops - Small-holder farming	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Species mortality
Geological events	Earthquakes/tsunamis	Timing		Scope		Severity		Impact
		Past, Unlikely to Return		Unknown		Unknown		Past Impact
		Stresses Ecosystem degradation, Species mortality
Pollution	Agricultural & forestry effluents - Herbicides and pesticides	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Negligible declines		Low Impact: 4
		Stresses Other
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Future		Unknown		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion
Residential & commercial development	Housing & urban areas	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion
Transportation & service corridors	Roads & railroads	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Ecosystem degradation, Ecosystem conversion

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