Data Zone
Justification of Red List category
This boobook is endemic to Mindanao and its satellites, where it is relatively widespread in remaining lowland forest. Because of forest loss caused by timber extraction and conversion to plantations, the population is believed to be declining moderately rapidly (15-25% over three generations: c. 16 years). Accordingly, it is listed as Near Threatened.
Population justification
The global population size has not been quantified but is believed to be large given the range and frequency of records in suitable habitat. Descriptively, it is considered 'uncommon' (Allen 2020). It is a forest-dependent species and appears to occur only in relatively intact forest (eBird 2023). Within its range, the rate of forest loss for timber extraction and conversion to (mostly rubber) plantations has been relatively rapid over the past few decades (per Global Forest Watch 2023). There are recent records from remaining forested areas across the range, however the extent of suitable habitat is now considerably smaller than three generations ago. Although no accurate estimation of the species' population size has been made, it almost certainly exceeds 10,000 mature individuals based on the extent of suitable habitat remaining, although this requires data-led confirmation.
Trend justification
There are no population data available for this species from which to derive estimated rates of reduction. However, as a forest-dependent species, its population size is thought to be closely tied to the extent of available forest, thus rates of forest cover loss are here used as a proxy for population reduction. Over the past three generations (c. 16 years: 2006-2022), forest cover in this species' (elevational and geographic) range reduced by c. 14-17%, depending on the assumptions used (per Global Forest Watch 2023, based on data from Hansen et al. [2013] and methods disclosed therein). There are two reasons why this may be reasonably considered an underestimate for population reduction. First, it does not account for habitat degradation that is undetectable to remote sensing data, nor the impacts of fragmentation and extinction debt effects imposed on small and isolated forest blocks. Moreover, this species appears to be commonest in lowland habitats, which may reasonably be expected to have undergone more rapid rates of forest loss due to their easier access to loggers. Consequently, over the past three generations, the population is suspected of having declined by 15-25%. The same rate is of reduction is also applied to the window 2010-2026, and over the next three generations (2023-2039).
Ninox spilocephala is endemic to the island of Mindanao and its smaller satellite islands Dinagat, Siargao and Basilan, in the Philippines (Rasmussen et al. 2012).
It occurs in primary and tall secondary forest. It is apparently confined to the lowlands, with no records above 1,000 m, ad most records from forest <600 m (eBird 2023).
The key threat to this species is forest loss, principally driven by timber extraction and the conversion of forest to plantations (chiefly rubber and oil palm). This has been especially acute in Mindanao's lowlands, where this species favours. Overall, these impacts are thought to have caused declines of 15-25% over the past three generations.
Conservation and research actions underway
No specific action is known for this species. Most protected areas on Mindanao shield forest at elevations too high for it (UNEP-WCMC and IUCN 2023) and there even where illegal, there is evidence for encroachment into lowland forests.
Conservation and research actions proposed
Carry out surveys to assess the population size. Study the species' ecology, life history and especially habitat tolerances. Continue to monitor the extent and condition of suitable habitat using remote sensing data. Lobby for protection of remaining lowland forest.
Text account compilers
Berryman, A.
Contributors
Butchart, S., Ekstrom, J., Hutchinson, R., Ledesma, M., Symes, A., Taylor, J. & Westrip, J.R.S.
Recommended citation
BirdLife International (2024) Species factsheet: Mindanao Boobook Ninox spilocephala. Downloaded from
https://datazone.birdlife.org/species/factsheet/mindanao-boobook-ninox-spilocephala 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.