NT
Chestnut-backed Owlet Glaucidium castanotum



Taxonomy

Taxonomic note
Glaucidium castanotum (del Hoyo and Collar 2014) was previously listed as G. castanonotum.

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. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2016 Near Threatened C1
2013 Near Threatened C1
2012 Near Threatened C1
2008 Near Threatened B1a+b(iii); C1
2004 Near Threatened
2000 Lower Risk/Near Threatened
1994 Lower Risk/Near Threatened
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency High
Land mass type Land-mass type - shelf island
Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 63,500 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 10000-19999 poor suspected 2008
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 - - -
Largest subpopulations - - -
Generation length (yrs) 3.8 - - -

Population justification: This species is assumed to have a moderately small population as it is generally uncommon within lowland wet zone forest on Sri Lanka. It is estimated to number 10,000-19,999 mature individuals, equating to 15,000-29,999 individuals in total, rounded here to 15,000-30,000 individuals. Further research is required to refine this estimate.

Trend justification: The population is suspected to be in slow to moderate decline owing to on-going habitat destruction and degradation. The rate of decline is not thought to be more rapid because the species seems able to tolerate human-modified habitats.


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

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

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane major resident
Altitude 0 - 1950 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting Timing Scope Severity Impact
Past, Unlikely to Return Minority (<50%) Slow, Significant Declines Past Impact
Stresses
Ecosystem degradation, Ecosystem conversion
Natural system modifications Fire & fire suppression Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Natural system modifications Fire & fire suppression Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2019) Species factsheet: Glaucidium castanotum. Downloaded from http://www.birdlife.org on 20/03/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 20/03/2019.