EN
Horned Guan Oreophasis derbianus



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
- C2a(i) C2a(i); D1

Red List history
Year Category Criteria
2020 Endangered C2a(i)
2016 Endangered C2a(i)
2013 Endangered C2a(i)
2012 Endangered C2a(i)
2008 Endangered C2a(i)
2004 Endangered
2000 Endangered
1996 Vulnerable
1994 Vulnerable
1988 Threatened
Species attributes

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

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 56,300 medium
Number of locations 6-10 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 600-1700 medium estimated 2000
Population trend Decreasing poor 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) 20-29 - - -
Decline (10 years/3 generation past and future) 20-29 - - -
Number of subpopulations 2-100 - - -
Percentage in largest subpopulation - - -
Generation length (yrs) 9.55 - - -

Population justification: The population is thought to number 1,000-2,499 individuals, based on an estimate of 1,000 in late 1970s and more recent information that some areas such as El Triunfo may be secure and hold relatively high densities. The core of this biosphere reserve alone could hold a population of 2,475-3,685 birds, but the band of 1,000-2,499 individuals is precautionarily retained here. This estimate equates to 667-1,666 mature individuals, rounded here to 600-1,700 mature individuals. Population density estimates for El Triunfo are 2.6-5.2 individuals/km2 (González-García 1992, 1994), 4.5-7.1 individuals/km2 (Gomez de Silva et al. 1999) and 3.7 individuals/km2 (Abundis-Santamaría and González-García 2006), equivalent to a population of 2,475-3,685 birds for the core of the biosphere reserve (González-García 2005, SEMARNAT 2011). In Guatemala, at Volcán San Pedro the estimates are 10.5 individuals/km2 (Rivas Romero and Cóbar Carranza 2008) and for Sierra de las Minas the estimates are 1.6 individuals/km2 (Quiñonez 2010).

Trend justification: The population is suspected to be declining, in line with the clearance and degradation of cloud-forest within its range, estimated to be occurring at rates of ~4% per three generations (Tracewski et al. 2016). Due to potentially high levels of hunting and trapping, the rate of population decline is tentatively placed in the band 20-29% over three generations.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
Guatemala N Extant Yes
Mexico N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Guatemala Atitlan
Guatemala Cerro El Amay
Guatemala Sierra de las Minas - Motagua
Guatemala Tacana - Tajumulco
Guatemala Santiaguito Volcano
Guatemala Antigua Guatemala
Guatemala Cuchumatanes
Mexico Chimalapas
Mexico El Tacaná
Mexico El Triunfo
Mexico Peña Blanca
Mexico Cerro Mozotal - Tacaná
Mexico Montebello II
Mexico Subcuenca Sesecapa
Mexico Pico de Loro El Paxtal - El Triunfo
Mexico La Frailescana

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Montane major resident
Altitude 1400 - 3500 m Occasional altitudinal limits  

Threats & impact
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
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
Past, Likely to Return Majority (50-90%) Slow, Significant Declines Past Impact
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
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Unknown Unknown
Stresses
Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Bos taurus Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation
Transportation & service corridors Roads & railroads 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
Pets/display animals, horticulture - - International Non-trivial Recent

Recommended citation
BirdLife International (2022) Species factsheet: Oreophasis derbianus. Downloaded from http://www.birdlife.org on 27/06/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 27/06/2022.