• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
The global population is suspected to number 50,000-499,999 mature individuals (Partners in Flight 2022).

Trend justification
The population trend has not been investigated. Tree cover within the range is lost at a rate of 15% over three generations (Global Forest Watch 2021, using Hansen et al. [2013] data and methods disclosed therein). Apart from forests, the species is also found in woodland, plantations, thorn scrub and man-made habitats, including urban parks (Arizmendi et al. 2020); consequently, the current rate of tree cover loss may not be driving an equivalent population decline. Nevertheless, the species is sometimes locally killed out of concern that it may prey on domestic chickens (Arizmendi et al. 2020), though the impact on the population size has not been quantified. Tentatively, population declines are here placed in the band 10-19% over three generations.

Text account compilers
Hermes, C.

Contributors
Butchart, S. & Ekstrom, J.

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Recommended citation
BirdLife International (2024) Species factsheet: Stygian Owl Asio stygius. Downloaded from https://datazone.birdlife.org/species/factsheet/stygian-owl-asio-stygius 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.