Data Zone
Justification of Red List category
This species has a small range that is experiencing ongoing habitat loss and degradation. Although historically this was mostly peripheral and coastal, there is increasing evidence that interior forest is being lost and degraded, especially on Yamdena. For now, there is no evidence that the species is declining rapidly, nor that it has a small population size, although both factors should be monitored closely. It is currently considered Near Threatened.
Population justification
The global population size has not been quantified, but the species is reported to be moderately common (Coates et al. 1997; Eaton et al. 2016, 2021).
Trend justification
Data on population trends are lacking but moderate declines are suspected on the basis of ongoing forest loss. Remote sensing data (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein) indicate that in the ten years to 2022, forest cover in the species' range reduced by 5-6%. This species is considered highly forest dependent (Haryoko et al. 2021), and these forest losses are suspected of having had a broadly similar (1-9% over ten years) reduction in the species' population size. Forest loss appears to be ongoing and the same rate is therefore suspected to continue into the future.
Carterornis castus is confined to the Banda Sea Islands Endemic Bird Area, Indonesia, where it occurs in the Tanimbar Islands.
This species inhabits primary and secondary forest in the lowlands (Eaton et al. 2021, Haryoko et al. 2021).
Habitat loss and degradation is the key threat to this species and is suspected of causing slow but significant declines. Across its range, forest cover extent reduced by 5-6% in the ten years to 2022 (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). Of particular concern, in the north-centre of Yamdena, logging tracks have now infiltrated into the interior of the island (Google Earth 2022).
Conservation Actions Underway
No targeted conservation action is known for this species, although some of its habitat is protected.
Conservation Actions Proposed
Quantify the population size. Monitor populations and habitat trends on occupied islands. Conduct ecological studies to improve understanding of its precise habitat requirements, tolerance of secondary habitats and response to fragmentation. As a precaution, protect significant areas of suitable forest, in both strictly protected areas and community-led multiple use areas.
Text account compilers
Berryman, A.
Contributors
Butchart, S. & Ekstrom, J.
Recommended citation
BirdLife International (2024) Species factsheet: Tanimbar Monarch Carterornis castus. Downloaded from
https://datazone.birdlife.org/species/factsheet/tanimbar-monarch-carterornis-castus 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.