Justification of Red List category
This scarce and poorly known species has a highly restricted range, and is likely to have a moderately small global population size. Habitat loss is suspected to be causing slow population declines in parts of the range. It is therefore currently considered Near Threatened.
Population justification
This is a poorly known species and no population estimates are available.
Trend justification
Some habitat loss is occurring within the lower altitudinal range of this species, thus a slow population decline is likely to be taking place.
Oriolus hosii is endemic to Borneo. In Sarawak, Malaysia, it is restricted to montane forest at 900-2,000 m, and has been historically recorded from Gn Kalulong, Gn Mulu, Gn Dulit, the Usun Apau Plateau, Gn Derian, Gn Murud Kecil, Batang Patap, Ulu Sabai and Tutoh. The species was recently seen in Sarawak for the first time since 1991, during an International Tropical Timber Organisation survey of Batu Lawi. It is also known from east Kalimantan, Indonesia, near to the border with Sarawak. It is rarely recorded and little is known; being usually noisy where it does occur, this paucity of records is thought to reflect genuine rarity (Orenstein et al. 2010).
This species is apparently restricted to mossy transitional forest around 1,100-1,200 m on the sandy north side of the Dulit range.
Habitat clearance through logging and agricultural development is now encroaching into montane areas within the species's range.
Conservation Actions Underway
It is known to occur within protected areas, including Kayan Mentarang National Park in east Kalimantan (Orenstein et al. 2010).
Conservation Actions Proposed
Conduct repeated surveys within its range to determine current distribution and abundance, as well as assess population trends and rates of habitat loss. Conduct ecological studies to improve understanding of its precise habitat requirements, tolerance of secondary habitats and response to fragmentation. Protect significant areas of suitable forest, in both strictly protected areas and community-led multiple use areas.
Text account compilers
Benstead, P., Gilroy, J., Khwaja, N., Taylor, J.
Recommended citation
BirdLife International (2024) Species factsheet: Black Oriole Oriolus hosii. Downloaded from
https://datazone.birdlife.org/species/factsheet/black-oriole-oriolus-hosii 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.