• Summary
• Text account
• Data table and detailed info
• Distribution map
• Reference and further resources

Taxonomic note

Alophoixus bres, A. frater and A. tephrogenys (del Hoyo and Collar 2016) were previously lumped as A. bres following Sibley and Monroe (1990, 1993).

 

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.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	A2cd+3cd+4cd

Red List history

Year	Category	Criteria
2020	Vulnerable	A2cd+3cd+4cd
2016	Least Concern
2012	Not Recognised
2008	Not Recognised
2004	Not Recognised
2000	Not Recognised
1994	Not Recognised
1988	Not Recognised

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	3,310,000 km2
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	unknown	-	-	-
Population trend	decreasing	-	inferred	2014-2024
Rate of change over the past 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	30-49%	-	-	-
Generation length	2.8 years	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: The species is described as common to very common, and locally numerous across Thailand and Malaysia (del Hoyo et al. 2020, J. Eaton in litt. 2020). Population densities are estimated to be 10-14.5 individuals/km² (observed across logged forests of Borneo and Sumatra; del Hoyo et al. 2020). Based on recent concerns of the rate of trapping pressures inflicted across the species's range however, it is likely that the population has lowered considerably. Thus, due to high uncertainty, the population size has not been quantified.

Trend justification: Based on a recent analyses by Symes et al. (2018), the species was considered to be undergoing a decline of 73.8% over a 10-year period, as estimated using data gathered between 2000-2015. Declines were attributed to the combined effect of habitat loss and trapping pressures (Symes et al. 2018, [also Tracewski et al. 2016]). However, due to the species's tolerance to some extent of forest degradation, the rate of decline is thought to not be as significant. Additionally, Harris et al. (2016) show that the species may have undergone a slight increase (c. 0.148 as estimated by a mean coefficient) during 1998-2011, observed during field sampling at Way Canguk Research and Training Area, in the Bukit Barisan Selatan National Park. 
Furthermore, in comparison to the Brown-cheeked Bulbul Alophoixus bres, undergoing a very rapid decline of at least 50% across 10 years (S. Marsden in litt. 2020) based on more significant rates of exploitation and its subsequent disappearance from many sites across its range, it is suspected that A. tephrogenys, although subjected to population reduction, is not equivalent to the rate at which A. bres has declined. Thus, the species is thought to be experiencing a rapid decline of 30-49% over a three-generation period. A continued population decline can be inferred using numbers recorded in bird markets; 34 birds observed in July 2015 as compared to only 5 birds observed in July 2019 (J. Eaton in litt. 2020).

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
Thailand	extant	native	yes

Country/Territory	IBA Name
Malaysia	Belum-Temenggor
Malaysia	Bintang Range
Malaysia	Danum Valley Conservation Area
Malaysia	Endau-Rompin
Malaysia	Gunung Pueh
Malaysia	Kabili-Sepilok
Malaysia	Kinabatangan floodplain
Malaysia	Krau Wildlife Reserve
Malaysia	Kulamba Wildlife Reserve
Malaysia	Lambir Hills National Park
Malaysia	Lanjak Entimau Wildlife Sanctuary
Malaysia	Maliau Basin Conservation Area
Malaysia	Mount Kinabalu
Malaysia	Mulu - Buda Protected Area
Malaysia	Nakawan Range
Malaysia	Niah National Park
Malaysia	Panti forest
Malaysia	Selangor Heritage Park
Malaysia	Similajau National Park
Malaysia	Tabin Wildlife Reserve
Malaysia	Taman Negara National Park
Malaysia	Tanjung Datu-Samunsam Protected Area
Malaysia	Tawau Hills Park
Malaysia	Ulu Muda

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
Altitude	0 - 1150 m	Occasional altitudinal limits	(max) 1500 m

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Wood & pulp plantations - Agro-industry plantations	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Biological resource use	Hunting & trapping terrestrial animals - Intentional use (species is the target)	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species mortality
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
Natural system modifications	Fire & fire suppression - Increase in fire frequency/intensity	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation, Ecosystem conversion

Purpose	Scale
Pets/display animals, horticulture	international

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Recommended citation
BirdLife International (2024) Species factsheet: Grey-cheeked Bulbul Alophoixus tephrogenys. Downloaded from https://datazone.birdlife.org/species/factsheet/grey-cheeked-bulbul-alophoixus-tephrogenys on 22/12/2024.
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 22/12/2024.