NT
Togian Boobook Ninox burhani



Justification

Justification of Red List category
This species likely has a small population within a small range. Within this, habitat loss is ongoing moderately rapidly, although this species appears to exhibit at least some tolerance to degraded habitats. For these reasons it is currently classified as Near Threatened.

Population justification
The population size of this species has never been formally estimated, although it is described as 'fairly common' by Eaton et al. (2021). Citizen science data (eBird 2023) affirm this description and suggest it occurs at relatively high density in areas for which it has been searched. Remote sensing data indicate that c.600 km2 of forest remains in its range (per Global Forest Watch 2023), and most of this is suspected to be occupied given this species' apparent tolerance of degradation (Eaton et al. 2021). Few robust densities for Ninox owls are available, although Jakosalem et al. (2013) recorded densities of up to 20 mature individuals/km2 for Ninox rumseyi of Cebu. However, these data were based on home ranges from satellite-tracking that the authors acknowledged yielded territory sizes that were probably too small due to the short time the birds were followed for. The estimated home ranges were, for example, up to ten times smaller than that of Ninox boobook sensu stricto (Olsen et al. 2011). Assuming a density of 5-15 mature individuals/km2, and an occupancy of 70-90%, the population size of Ninox burhani is inferred to be 2,100-8,100 mature individuals.

Trend justification
The population trend of this species has not been directly assessed although it is suspected to be declining in response to forest cover loss, which appears to be accelerating. In the three generations (13.2 years; Bird et al. 2020) to 2021, approximately 10% of forest cover was lost in this species' mapped range. Between 2016 and 2021, this accelerated to a rate equivalent to c.13%. However, this species is evidently tolerant of some habitat degradation (Eaton et al. 2021, eBird 2023) and it therefore may not be declining in parallel with forest losses. To account for this uncertainty, it is suspected to have declined by 5-15% in the past three generations, and (precautionarily assuming 2016-2021 rates of loss continue) by 10-20% in the next three generations.

Distribution and population

Ninox burhani is endemic to the Togian archipelago off central Sulawesi, Indonesia (Verbelen and Demeulemeester 2010).

Ecology

A resident of lowland and hill forest, it has been recorded in scrubby woodland surrounded by evergreen forest and also in degraded forest, mixed gardens and sago swamp, at elevations from sea-level to 400 m (Verbelen and Demeulemeester 2010, Eaton et al. 2021).

Threats

Ongoing habitat clearance through agricultural expansion and subsistence logging represent the main threats to this species, which is suspected of having lost >10% in the three generations to 2022 (per Global Forest Watch 2023).

Conservation actions

Conservation Actions Underway
CITES Appendix II. A Togian Islands National Park was declared by the Ministry of Forestry in 2004, and includes over 250 km2 of terrestrial habitat, including areas in which this species is known to occur. Nonetheless, this does not appear to have been wholly effective in protected this area's forests from loss and degradation (per Global Forest Watch 2023).

Conservation Actions Proposed
Protect remaining areas of lowland forest. Enforce restrictions on agricultural encroachment and logging within such protected areas, while ensuring that communities are fully engaged are adequately remunerated (see Bunyamin and Purnomo 2017). Generate density estimates to inform a revised population estimate for the species. Continue to estimate population trends by calculating rates of forest loss within its range using satellite imagery and remote sensing techniques.

Identification

A medium-sized, brown hawk-owl, with white lower underparts from the lower breast to the vent, streaked with brown. Prominent white supercilia meet above the nasal area. Has white patches on its scapulars. Similar spp. It differs from other species by the combination of dark brown upperparts, white underparts below the breast streaked with brown, and its small size. Voice A throaty "raw", lasting 0.2 seconds, repeated every 3-4 seconds; or, a four-note "OOK_gr-ra-ra" lasting c.0.3 seconds (Eaton et al. 2021). 

Acknowledgements

Text account compilers
Berryman, A.

Contributors
Bird, J., Butchart, S., Crosby, M., Indrawan, M., Khwaja, N., Taylor, J. & Westrip, J.R.S.


Recommended citation
BirdLife International (2024) Species factsheet: Togian Boobook Ninox burhani. Downloaded from https://datazone.birdlife.org/species/factsheet/togian-boobook-ninox-burhani on 23/12/2024.
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 23/12/2024.