Justification of Red List Category
This species is listed as Near Threatened because there are some indications that it has a moderately small population, which is in decline owing to forest clearance and degradation.
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.
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.
Glaucidium castanotum is endemic to Sri Lanka, where it is a rare resident (BirdLife International 2001). Whilst it may be more common than records suggest, its range has diminished dramatically since the 19th century when it was widespread in the lowlands of Sri Lanka to the outskirts of Colombo. Declines are thought to be continuing.
It occurs in dense wet forests of the lowlands and hills, but has also been recorded in logged forests, rubber plantations, scrub and cultivation, and ranges up to 1,950 m. It is shy and retiring; generally keeping to the canopy of large trees, and is therefore probably overlooked. It feeds mostly on insects but also takes lizards, small mammals and small birds. Eggs are laid during March-May.
Forest on the island has suffered rapid degradation and fragmentation in the past decades through excessive gathering of fuelwood, clearance for permanent agriculture, shifting cultivation, fire, urbanisation and logging. Closed-canopy forest is estimated to have declined from 29,000 km2 (44% of the island's area) in 1956 to 12,260 km2 in 1983. It is feared that this loss will continue and the status of this species therefore requires monitoring.
Conservation Actions Underway
CITES Appendix II. A number of protected areas exist within the moist zone, and the species is still regularly recorded from Sinharaja Biosphere Reserve. A moratorium has been placed on further logging.
Text account compilers
Benstead, P., Bird, J., Taylor, J. & Symes, A.
BirdLife International (2020) Species factsheet: Glaucidium castanotum. Downloaded from http://www.birdlife.org on 02/07/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 02/07/2020.