VU
Javan Scops-owl Otus angelinae



Justification

Justification of Red List Category
This small owl qualifies for Vulnerable because its small range is undergoing contraction and increasing fragmentation through habitat loss, a factor that implies reductions in its small population. However, its silent, nocturnal habits and unobtrusive behaviour may have resulted in it being consistently under-recorded. Additional locality records and population data may require a reassessment of its threat status.

Population justification
The population is estimated to number 2,500-9,999 individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 1,667-6,666 mature individuals, rounded here to 1,500-7,000 mature individuals.

Trend justification
This poorly known species may be more common than available data suggest. However, owing to forest loss within its range, it is suspected to be declining, although the likely rate has not been estimated.

Distribution and population

Otus angelinae is endemic to the island of Java, Indonesia, where it is known from seven mountains, although there are recent records from only three (BirdLife International 2001). Most recent records come from Gunung Gede-Pangrango, where it is regarded as still fairly common (N. Brickle in litt. 2012) and surveys suggest it is also common in appropriate habitat on Gunung Salak, but absent from Gn Slamet and Ijen (Mittermeier et al. 2014). An evaluation of records and museum/zoo specimens, coupled with its reputed silence, suggests it may be more numerous and widespread than available evidence shows. A single specimen of this species, originally identified as Otus brooki, has been cited as evidence that the species occurs throughout highland areas in central and eastern Java (Konig et al. 2009).  Aside from this record, however, there are no confirmed reports of Javan Scops-owl outside of West Java and recent surveys on Slamet and Ijen (Mittermeier et al. 2014), though not exhaustive, did not find the species.  As with several other Javan endemics, it seems likely that this species is restricted to a few montane areas in West Java (Mittermeier in litt. 2016).

Ecology

It inhabits tropical upper montane forest between 1,000 m and 2,000 m. On Gn Salak it is found to be common at 1,400m (Mittermeier et al. 2014). Observations suggest a breeding territory size of very roughly 50 ha. Fledged young have been recorded in February, June and July, indicating egg-laying in at least May and December. It is presumed to be resident, perhaps making some altitudinal movements.

Threats

The main threat is from forest loss, degradation and fragmentation through widespread agricultural encroachment by shifting cultivators. Localised development (e.g. for holiday resorts and geothermal projects) is probably becoming an increasing threat in the lower part of its altitudinal range (1,000-1,500 m), particularly on unprotected mountain slopes. The area above this zone is still relatively secure.

Conservation actions

Conservation Actions Underway
CITES Appendix II. The species has been recorded recently in two protected areas, Gunung Gede-Pangrango National Park and Gunung Halimun Nature Reserve. These two areas cover over 500 km2 of forest between 500 m and 3,000 m. Nature Reserves exist on Gunung Tangkuban Prahu and Gunung Ijen, from where there are historical records.

Conservation Actions Proposed
Conduct extensive nocturnal fieldwork (including mist-netting) on mountains throughout Java to establish its true range and population status, and discover what vocalisations might aid detection. Support proposals to gazette further montane protected areas, and campaign for the establishment of new reserves (including Gunung Salak and Gunung Ciremai) or extensions to existing reserves. Improve protected-area management. Initiate conservation-awareness programmes around Javan forests.

Identification

16-18 cm. Small, rufous-brown, forest-dwelling owl. Rusty-brown facial disc, with prominent white eyebrows extending into ear-tufts. Rufous-brown upperparts, often with buffy or whitish (and distinctly black-tipped) collar and whitish scapular stripe. Whitish or creamy underparts. Golden-yellow iris. Similar spp. Sunda Scops-owl O. lempiji is slightly larger with generally greyer facial disc, buffy eyebrows, brown or orange iris and different call. Voice Usually silent, but gives explosive poo-poo in alarm and (especially young birds) prolonged hissing contact note. Hints Possibly most easily found by listening for hissing or wailing of fledglings.

Acknowledgements

Text account compilers
Benstead, P., Bird, J., Davidson, P., Taylor, J., Tobias, J., Allinson, T, Martin, R, North, A.

Contributors
Mittermeier, J., Brickle, N.


Recommended citation
BirdLife International (2019) Species factsheet: Otus angelinae. Downloaded from http://www.birdlife.org on 17/11/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 17/11/2019.