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Buff-vented Bulbul Iole olivacea

Justification
This species is relatively tolerant of secondary and degraded forest habitats, and therefore remains relatively common and widespread across much of its range. However, it is likely to be declining moderately rapidly overall as a result of widespread deforestation for timber and conversion to agriculture, and is therefore considered Near Threatened.

Taxonomic source(s)
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

Distribution and population
Iole olivacea is restricted to the Sundaic lowlands of south Tenasserim, Myanmar, peninsular and west Thailand, Singapore (scarce), Sabah, Sarawak and Peninsular Malaysia, Kalimantan (including the Natuna and Anamba islands) and Sumatra (including offshore islands), Indonesia and Brunei, where it is generally a common bird in suitable habitats (BirdLife International 2001).

Population justification
The global population size has not been quantified, but the species is described as common, although very scarce in Singapore (del Hoyo et al. 2005).

Trend justification
This species is likely to be negatively influenced by the wholesale clearance of habitat taking place within its range, and is therefore suspected to be in moderately rapid decline overall.

Ecology
This species is found in broadleaved evergreen forests in lowlands and hills, up to 825 m. It occurs in logged and secondary forests, as well as overgrown plantations and peat-swamp forest. It is most commonly encountered at forest edges or light-gaps within forest.

Threats
This species's tolerance of secondary and edge habitats suggests that it is not at immediate risk from habitat loss. However, it is inevitably affected by wholesale habitat clearance, which is occurring across large parts of the Sundaic region, with deliberate targeting of all remaining stands of valuable timber including those inside protected areas. Forest fires have also had a damaging effect (particularly in 1997-1998).

Conservation Actions Underway
No targeted conservation actions are known for this species, although it occurs in a number of protected areas.

Conservation Actions Proposed
Conduct repeated surveys within the species's range to 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. Increase the area of suitable primary forest with protected status and safeguard against on-going clearance. Improve the management of existing protected areas in the species's range. Designate forestry reserves in which only selective logging takes place. Encourage secondary growth and forest restoration in logged areas. Implement measures to reduce the number and severity of forest fires.

References
BirdLife International. 2001. Threatened birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, U.K.

del Hoyo, J.; Elliott, A.; Christie, D. 2005. Handbook of the Birds of the World, vol. 10: Cuckoo-shrikes to Thrushes. 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

Search for 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 (2014) Species factsheet: Iole olivacea. Downloaded from http://www.birdlife.org on 02/10/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 02/10/2014.

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.

Additional resources for this species

ARKive species - Buff-vented bulbul (Iole olivacea) 0

Key facts
Current IUCN Red List category Near Threatened
Family Pycnonotidae (Bulbuls)
Species name author Blyth, 1844
Population size Unknown mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 1,130,000 km2
Country endemic? No
Links to further information
- Additional Information on this species