VU
Great Hornbill Buceros bicornis



Taxonomy

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - A3cd+4cd

Red List history
Year Category Criteria
2018 Vulnerable A3cd+4cd
2016 Near Threatened A2cd+3cd+4cd; C1
2013 Near Threatened A2cd+3cd+4cd; C1
2012 Near Threatened A2cd+3cd+4cd;C1
2008 Near Threatened A2c,d; A3c,d; A4c,d; C1
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 High
Land mass type Land-mass type - continent
Land-mass type - shelf island
Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 10,300,000 medium
Number of locations -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 13000-27000 poor inferred 0
Population trend Decreasing medium 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 - - -
Largest subpopulations - - -
Generation length (yrs) 18.4 - - -

Population justification: Consistent population densities within protected areas in west and northeast India and Thailand of between 1.3 and 4 individuals per km2 indicate that the population within these sites, given the approximate habitat that lies within a suitable elevation range, can be estimated on a precautionary basis at 23,000 - 71,000 individuals. This is placed in the band 20 - 49,999 individuals, roughly equating to 13,000 - 27,000 mature individuals. Outside protected areas, even if adjacent, population densities can be considerably lower, often well below 1 individual per km2 (Gale and Thongaree 2006, Mudappa and Raman 2009, Naniwadekar et al. 2015).

Trend justification: An analysis of deforestation between 2000 and 2012 estimated forest loss within the species's range at 26.1% over three generation lengths (55.2 years) (Tracewski et al. 2016). The species is generally intolerant of forest disturbance and additionally severely threatened by hunting. Thus, its actual rate of population decline is likely greater than the estimate decline based on forest loss alone. The rate of decline is tentatively placed in the band 30-49% over three generations. Since this species has a long generation length, with three generations stretching over 55 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 distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Bangladesh V Extant
Bhutan N Extant Yes
Cambodia N Extant Yes
China (mainland) N Extant Yes
India N Extant Yes
Indonesia N Extant Yes
Laos N Extant Yes
Malaysia N Extant Yes
Myanmar N Extant Yes
Nepal N Extant Yes
Thailand N Extant Yes
Vietnam N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Nepal Barandabhar forests and wetlands
Nepal Bardia National Park
Nepal Chitwan National Park
Nepal Mai Valley forests
Nepal Parsa Wildlife Reserve
Vietnam Kon Cha Rang
Vietnam Yok Don

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Forest Subtropical/Tropical Moist Montane major resident
Altitude 0 - 2000 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 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 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
Biological resource use Logging & wood harvesting - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
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%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

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

Recommended citation
BirdLife International (2019) Species factsheet: Buceros bicornis. Downloaded from http://www.birdlife.org on 24/06/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 24/06/2019.