NT
Buff-vented Bulbul Iole charlottae



Taxonomy

Taxonomic note
Iole charlottae (del Hoyo and Collar 2016) was previously listed as I. olivacea.

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - -

Red List history
Year Category Criteria
2016 Near Threatened A2c+3c+4c
2012 Near Threatened A2c+3c+4c
2008 Near Threatened A2c; A3c; A4c
2004 Near Threatened
2000 Lower Risk/Near Threatened
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency medium
Land-mass type continent
shelf island
Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 3,930,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size unknown - - -
Population trend decreasing poor suspected 2011-2022
Rate of change over the past 10 years/3 generations (longer of the two periods) 20-29% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 20-29% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 20-29% - - -
Generation length 3.5 years - - -

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.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Brunei extant native yes
Indonesia extant native yes
Malaysia extant native yes
Myanmar extant native yes
Singapore extant native yes
Thailand extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Malaysia Nakawan Range
Malaysia Ulu Muda
Malaysia Bintang Range
Malaysia Belum-Temenggor
Malaysia Kledang Range
Malaysia Central Titiwangsa Range
Malaysia Selangor Heritage Park
Malaysia Endau-Rompin
Malaysia Panti forest
Malaysia Krau Wildlife Reserve
Malaysia Taman Negara National Park
Malaysia South-east Pahang peat swamp forest
Malaysia Kinabatangan floodplain
Malaysia Danum Valley Conservation Area
Malaysia Maliau Basin Conservation Area
Malaysia Tabin Wildlife Reserve
Malaysia Kabili-Sepilok
Malaysia Tanjung Datu-Samunsam Protected Area
Malaysia Gunung Pueh
Malaysia Bako-Buntal Bay
Malaysia Gunung Penrissen
Malaysia Sadong-Saribas coast
Malaysia Lanjak Entimau Wildlife Sanctuary
Malaysia Similajau National Park
Malaysia Niah National Park
Malaysia Lambir Hills National Park
Thailand Bala Sector, Hala-Bala Wildlife Sanctuary
Thailand Bu Do - Sungai Padi
Thailand Chaloem Pra Kiet (Pa Phru to Daeng)
Thailand Hala Sector, Hala-Bala Wildlife Sanctuary and Bang Lang National Park
Thailand Kaeng Krachan
Thailand Khao Banthad
Thailand Khao Luang
Thailand Khao Nor Chuchi
Thailand Thaleban

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Plantations suitable resident
Artificial/Terrestrial Subtropical/Tropical Heavily Degraded Former Forest suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane suitable resident
Forest Subtropical/Tropical Swamp suitable resident
Altitude 0 - 825 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Ecosystem degradation
Natural system modifications Fire & fire suppression - Increase in fire frequency/intensity Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation

Recommended citation
BirdLife International (2024) Species factsheet: Iole charlottae. Downloaded from https://datazone.birdlife.org/species/factsheet/buff-vented-bulbul-iole-charlottae on 05/03/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org on 05/03/2024.