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Writhed Hornbill Rhabdotorrhinus leucocephalus
BirdLife is updating this factsheet for the 2016 Red List
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This poorly known species is listed as Near Threatened as it is likely to be declining moderately rapidly owing to habitat loss, as well as exploitation by hunters and trappers. Its population size could be small, as it is largely restricted to primary forest, and it should be carefully monitored.

Taxonomic source(s)
del Hoyo, J.; Collar, N. J.; Christie, D. A.; Elliott, A.; Fishpool, L. D. C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Barcelona, Spain and Cambridge UK: Lynx Edicions and BirdLife International.

Taxonomic note
Rhabdotorrhinus leucocephalus (del Hoyo and Collar 2014) was previously placed in the genus Aceros.

Aceros leucocephalus (Vieillot, 1816)

Distribution and population
Aceros leucocephalus is endemic to the Philippines occurring on three islands, Mindanao and its two small satellites Camiguin Sur and Dinagat (Collar et al. 1999). It is poorly known, but considered locally fairly common in suitable habitat.

Population justification
The population size of this species has not been quantified, but it has been described as rare in general.

Trend justification
Data on trends are lacking, but a moderately rapid population decline is likely to be taking place as a result of habitat loss, as well as pressure from hunting and trapping.

This species is poorly known, but most records come from between 300 and 1,000 m in primary lowland forest.

This species is threatened by forest clearance for agriculture and logging, particularly given its strong links to unspoilt primary forest. It is also subject to pressure from hunting and trapping for trade.

Conservation Actions Underway
CITES Appendix II. Conservation Actions Proposed
Conduct repeated surveys across the species's range to determine the magnitude of declines and rates of range contraction. Campaign for the protection of remaining tracts of lowland forest throughout the species's range. Monitor hunting and trapping pressure.

Collar, N. J.; Mallari, N. A. D.; Tabaranza, B. R. J. 1999. Threatened birds of the Philippines: the Haribon Foundation/BirdLife International Red Data Book. Bookmark, Makati City.

del Hoyo, J.; Elliott, A.; Sargatal, J. 2001. Handbook of the Birds of the World, vol. 6: Mousebirds to Hornbills. Lynx Edicions, Barcelona, Spain.

Further web sources of information
Detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001).

Explore HBW Alive for further information on this species

View photos and videos and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Gilroy, J., Taylor, J.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2016) Species factsheet: Rhabdotorrhinus leucocephalus. Downloaded from on 26/10/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from on 26/10/2016.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Key facts
Current IUCN Red List category Near Threatened
Family Bucerotidae (Hornbills)
Species name author (Vieillot, 1816)
Population size Unknown mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 90,000 km2
Country endemic? Yes
Links to further information
- Additional Information on this species