LC
Olive Bulbul Iole viridescens



Taxonomy

Taxonomic note

Iole viridescens (del Hoyo and Collar 2016) was previously listed as I. virescens.

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.

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

Red List history
Year Category Criteria
2024 Least Concern
2016 Least Concern
2012 Least Concern
2009 Least Concern
2008 Least Concern
2004 Least Concern
2000 Lower Risk/Least Concern
1994 Lower Risk/Least Concern
1988 Lower Risk/Least Concern
Species attributes

Migratory status not a migrant Forest dependency high
Land-mass type Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 642,000 km2
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size unknown - - -
Population trend decreasing - suspected -
Generation length 3.23 years - - -

Population justification: The global population size has not been quantified, but the species is described as mostly very local and locally rare in India (del Hoyo et al. 2005). This species is considered to have a high dependency on forest habitat, and tree cover is estimated to have declined by 9.9% within its mapped range over the past 10 years (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). It is therefore tentatively suspected that this rate of cover loss may have led to a decline of between 1-19% in the species' population size over the same time frame, with a best estimate of reduction being 5-9%.

Trend justification:   .


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Bangladesh extant native yes
India extant native yes
Myanmar extant native yes
Thailand extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Thailand Huai Kha Khaeng
Thailand Mae Wong
Thailand Thung Yai - Naresuan

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Altitude 0 - 1000 m Occasional altitudinal limits  

Recommended citation
BirdLife International (2024) Species factsheet: Olive Bulbul Iole viridescens. Downloaded from https://datazone.birdlife.org/species/factsheet/olive-bulbul-iole-viridescens on 23/11/2024.
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 23/11/2024.