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

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
-	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

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	56,300 km2	medium
Number of locations	6-10	-
Severely fragmented?	yes	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	600-1700 mature individuals	medium	estimated	2000
Population trend	decreasing	poor	inferred	1995-2024
Rate of change over the past 10 years/3 generations (longer of the two periods)	20-29%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	20-29%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	20-29%	-	-	-
Generation length	9.55 years	-	-	-
Number of subpopulations	2-100	-	-	-

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	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Guatemala	extant	native	yes
Mexico	extant	native	yes

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 Triunfo

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	1400 - 3500 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 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

Purpose	Primary form used	Life stage used	Source	Scale	Level	Timing
Food - human	-	-			non-trivial	recent
Pets/display animals, horticulture	-	-		international	non-trivial	recent

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Recommended citation
BirdLife International (2023) Species factsheet: Oreophasis derbianus. Downloaded from http://datazone.birdlife.org/species/factsheet/horned-guan-oreophasis-derbianus on 29/11/2023.
Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://datazone.birdlife.org on 29/11/2023.