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

Justification of Red List category
Although this species has a small range and a moderately small population size, there are no threats acting in its range thought to be causing declines in population size, occurrence/occupancy, or habitat area. It therefore does not meet or approach either 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), the population trend criterion (>30% decline over ten years or three generations), or 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 it is assessed as Least Concern.

Population justification
The population size of this species has not been formally estimated. It was described as uncommon by Eaton et al. (2021). Survey efforts in 1995?1996 and in 2011 generated few records of the species (Reeve et al. 2014) but inside forest in optimal habitat, pairs can be spaced only c.200 m apart (J. Eaton in litt. 2022). Assuming that this description translates to a density of c.50 mature individuals/km², and that c.20-40% of forest within its elevational range (totalling 1,400 km²) is occupied, the population is estimated here to number 14,000-28,000 mature individuals.

Trend justification
The population is suspected to be stable in the absence of evidence for any declines or substantial threats. Remote sensing data (Global Forest Watch 2022, using data from Hansen et al. [2013] and methods disclosed therein) indicate minimal (<1% over ten years) forest loss in this species' elevational range and it is also reported to be at least somewhat tolerant of degraded habitats, including grasslands (White and Bruce 1986, Coates and Bishop 1997).

The species is endemic to Buru, Indonesia.

It inhabits the undergrowth of montane forest, principally above 1,200 m, but occasionally down to 750 m (Eaton et al. 2021, J. Eaton in litt. 2022).

The only plausible threat to this species is forest loss, although this is currently occurring at a rate so slow that declines cannot be assumed. This species' preference for remote montane forests buffers it from the most extreme forest loss in the lowlands.

Conservation Actions Underway
None specific to this species.

Conservation Actions Proposed
Continue to monitor forest loss data.

Text account compilers
Berryman, A.

Contributors
Eaton, J.

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Recommended citation
BirdLife International (2024) Species factsheet: Buru Grasshopper-warbler Locustella disturbans. Downloaded from https://datazone.birdlife.org/species/factsheet/buru-grasshopper-warbler-locustella-disturbans 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.