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

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

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	A3cd+4cd

Red List history

Year	Category	Criteria
2018	Vulnerable	A3cd+4cd
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

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

	Estimate	Data quality
Extent of Occurrence breeding/resident (km2)	7,020,000
Number of locations		-
Severely Fragmented		-

	Value	Data quality	Derivation	Year of estimate
No. of mature individuals	unknown	not applicable	not applicable	0
Population trend	Decreasing		inferred	-
Decline (3 years/1 generation past)		-	-	-
Decline (5 years/1 generation past)		-	-	-
Decline (10 years/1 generation past)		-	-	-
Decline (10 years/3 generation future)	30-39	-	-	-
Decline (10 years/3 generation past and future)	30-39	-	-	-
Number of subpopulations		-	-	-
Percentage in largest subpopulation		-	-	-
Generation length (yrs)	19	-	-	-

Population justification: The global population size has not been quantified, but the species is reported to be locally common in several areas across its wide range (del Hoyo et al. 2001).

Trend justification: The population is suspected to be in decline owing to ongoing habitat destruction and fragmentation (del Hoyo et al. 2001). An analysis of deforestation between 2000 and 2012 estimated forest loss within the species's range at 32.8% over three generations (57 years) (Tracewski et al. 2016). The rate of population decline is suspected to be greater than this because the species is intolerant of degraded and secondary habitat, but requires large tracts of undisturbed forest. In addition, it is also threatened by hunting. Thus, the rate of decline is precautionarily placed in the band 30-49% over three generations. Since this species has a long generation length, with three generations stretching over 57 years, there is insufficient evidence to calculate the magnitude of reduction over the past three generations. Assuming the recent rate of decline remains constant, the species is projected to decline by 30-49% over the next three generations.

Country/Territory	Occurrence status	Presence	Resident	Breeding	Non-breeding	Passage
Bangladesh	N	Extant		Yes
Bhutan	N	Extant		Yes
Brunei	N	Extant		Yes
Cambodia	N	Extant		Yes
India	N	Extant		Yes
Indonesia	N	Extant		Yes
Laos	N	Extant		Yes
Malaysia	N	Extant		Yes
Myanmar	N	Extant		Yes
Thailand	N	Extant		Yes
Vietnam	N	Extant		Yes

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Lowland	major	resident
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	0 - 2560 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
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 Species disturbance, Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Small-holder grazing, ranching or farming	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species disturbance, 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	Hunting & trapping terrestrial animals - Unintentional effects (species is not the target)	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Species mortality

Purpose	Primary form used	Life stage used	Source	Scale	Level	Timing
Food - human	-	-			Non-trivial	Recent
Medicine - human & veterinary	-	-			Non-trivial	Recent
Pets/display animals, horticulture	-	-		International	Non-trivial	Recent

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Recommended citation
BirdLife International (2022) Species factsheet: Rhyticeros undulatus. Downloaded from http://www.birdlife.org on 18/08/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 18/08/2022.