Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Bucerotiformes Bucerotidae

Scientific Name: Rhinoplax vigil
Species Authority: (Forster, 1781)
Common Name(s):
English Helmeted Hornbill
Spanish Cálao de Casco
Buceros vigil BirdLife International (2000)
Buceros vigil vigil Collar and Andrew (1988)
Buceros vigil vigil Sibley and Monroe (1990, 1993)
Buceros vigil vigil Collar et al. (1994)
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. Lynx Edicions BirdLife International.
Taxonomic Notes: Use of the genus Rhinoplax follows BirdLife International (2001).

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Facilitator/Compiler(s): Benstead, P., Gilroy, J. & Taylor, J.
This forest-dependent species is likely to be declining moderately rapidly throughout its range as a result of habitat loss and hunting pressure. It is considered Near Threatened, and should be carefully monitored in case of future increases in the rate of decline.

Previously published Red List assessments:
2008 Near Threatened (NT)
2004 Near Threatened (NT)
2000 Lower Risk/near threatened (LR/nt)
1994 Lower Risk/near threatened (LR/nt)
1988 Threatened (T)

Geographic Range [top]

Range Description: Rhinoplax vigil is confined to the Sundaic lowlands, where it is known from south Tenasserim, Myanmar, peninsular Thailand, Sabah, Sarawak and Peninsular Malaysia, Singapore, Kalimantan and Sumatra, Indonesia and Brunei (BirdLife International 2001). It is generally scarce and occurs at low densities even in optimal habitat.

Countries occurrence:
Brunei Darussalam; Indonesia; Malaysia; Myanmar; Thailand
Regionally extinct:
Continuing decline in area of occupancy (AOO): Yes
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 1220000
Continuing decline in extent of occurrence (EOO): Yes
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: Yes
Extreme fluctuations in the number of locations: No
Upper elevation limit (metres): 1100
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: The population size of this species has not been quantified; it is considered locally common.

Trend Justification:  A moderately rapid decline is suspected to be occurring in this species's population as a result of habitat loss and, to a lesser extent, hunting pressure.
Current Population Trend: Decreasing
Additional data:
Number of mature individuals: Unknown Continuing decline of mature individuals: Yes
Extreme fluctuations: No Population severely fragmented: No
Continuing decline in subpopulations: Yes
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No

Habitat and Ecology [top]

Habitat and Ecology: It occurs in primary semi-evergreen and evergreen lowland forest, up to 1,500 m. In particular, it prefers rugged terrain, especially in foothills, and can persist locally in selectively logged forest.

Systems: Terrestrial
Continuing decline in area, extent and/or quality of habitat: Yes
Generation Length (years): 19.8
Movement patterns: Not a Migrant

Threats [top]

Major Threat(s): Rates of forest loss in the Sundaic lowlands have been extremely rapid, owing partly to the escalation of illegal logging and land conversion, 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). The magnitude of these threats may be allayed by this species's tolerance of hill forest, which is under less pressure from logging and agricultural conversion. It is prized by hunters, although centuries of hunting have meant that it is very shy and wary, and therefore capture rates may be relatively low.

Conservation Actions [top]

Conservation Actions: Conservation Actions Underway
CITES I listed.

Conservation Actions Proposed
Monitor populations across the species's range to determine the magnitude of declines and rates of range contraction. Monitor the impact of hunting pressure on populations. Campaign for the protection of remaining tracts of lowland forest throughout the range.

Citation: BirdLife International. 2012. Rhinoplax vigil. The IUCN Red List of Threatened Species 2012: e.T22682464A38073187. . Downloaded on 07 October 2015.
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