Justification of Red List category
This species has a 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). The population trend is suspected of being stable and therefore the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been estimated but is not thought to 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 size has not been quantified. It is described as 'uncommon and local' (Eaton et al. 2021) however is extremely unobtrusive and overlooked and much of its large range remains unvisited (eBird 2022). Given the large area (c.27,000 km2) of forest within its range and elevation the population size is very likely to exceed 10,000 mature individuals.
Trend justification
This species is confined to largely inaccessible montane forest above c.1,400 m, where forest cover loss over the past 20 years has been minimal and many remaining areas lie in protected areas. In the three generations (11.9 years; Bird et al. 2020) to 2021, forest cover loss in this species' range was equivalent to only c.1-2% (Global Forest Watch 2022, based on Hansen et al. [2013] and methods disclosed therein). In the future, the extent of forest cover is also predicted to remain relatively stable (Voigt et al. 2021). In the absence of any other threats, the population trend is suspected to be stable.
Zoothera heinrichi is restricted to Sulawesi, Indonesia.
It inhabits primary montane forest with dense undergrowth, moss forest and dwarf forest at 1,400-3,500 m (Eaton et al. 2021). It is a wary species, feeding (typically singly) on arthropods on the forest floor.
Text account compilers
Berryman, A.
Contributors
Benstead, P., Bird, J. & Khwaja, N.
Recommended citation
BirdLife International (2024) Species factsheet: Geomalia Zoothera heinrichi. Downloaded from
https://datazone.birdlife.org/species/factsheet/geomalia-zoothera-heinrichi on 22/11/2024.
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 22/11/2024.