• 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.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	-

Red List history

Year	Category	Criteria
2021	Least Concern
2016	Near Threatened	C1+2a(i)
2012	Near Threatened	C1+2a(i)
2008	Near Threatened	C1; C2a(i)
2004	Near Threatened
2000	Lower Risk/Near Threatened
1994	Lower Risk/Near Threatened
1988	Near Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	87,600 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	2500-9999 mature individuals	poor	inferred	2021
Population trend	decreasing	poor	suspected	-
Generation length	2.4 years	-	-	-
Number of subpopulations	3	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: The population size has not been quantified directly. A congener (O. leucopleurus in Argentina) occurs at a density of 4-12 individuals/km² (Santini et al. 2018); however this is likely not representative for O. adela, whose density is considered not to exceed 4 individuals/km² (S. K. Herzog in litt. 2021). Assuming that only 10% of the mapped range is occupied to account for the species's rarity (i.e. 3,800 km²), the species may number at most 15,200 individuals, which roughly equates to 10,000 mature individuals. The population size is consequently here placed in the band 2,500-9,999 mature individuals.

Assuming that the species forms three separate subpopulations within its range, that 10% of the range is occupied at a density of up to 4 individuals/km², the largest subpopulation (occupying an area of 1,700 km², based on the area of the range polygon) may number up to 4,500 mature individuals.

Trend justification: The population trend has not been quantified. The species is able to tolerate substantial habitat degradation (Fjeldså and Kirwan 2020). However, due to the high anthropogenic pressure on natural habitat within the range, the species is precautionarily suspected to decline slowly owing to habitat degradation and destruction.

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Argentina	extant	native	yes
Bolivia	extant	native	yes

Country/Territory	IBA Name
Argentina	Queñoales de Santa Catalina
Argentina	Santa Victoria, Cañani y Cayotal
Argentina	Yavi y Yavi Chico
Bolivia	Cuencas de Ríos Caine y Mizque
Bolivia	Reserva Biológica Cordillera de Sama
Bolivia	Southern slopes of Tunari National Park (Vertiente Sur del Parque Nacional Tunari IBA)

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Shrubland	Subtropical/Tropical High Altitude	major	resident
Altitude	2550 - 4000 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		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture	Livestock farming & ranching - Agro-industry grazing, ranching or 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 - Scale Unknown/Unrecorded	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: (large scale) [harvest]	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation
Natural system modifications	Fire & fire suppression - Trend Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		Stresses Ecosystem degradation

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Recommended citation
BirdLife International (2024) Species factsheet: Wedge-tailed Hillstar Oreotrochilus adela. Downloaded from https://datazone.birdlife.org/species/factsheet/wedge-tailed-hillstar-oreotrochilus-adela on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.