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

Taxonomic note
Amazilia cyanifrons and A. alfaroana (HBW and BirdLife International 2017) were previously lumped as A. cyanifrons (del Hoyo and Collar 2014), but A. alfaroana is now recognised as a good species following Kirwan and Collar (2016), who examined the sole specimen and found species-level differences from cyanifrons and no evidence of characters suggesting that it is a hybrid, with the conclusion that - subject to any future molecular analysis - it is best treated as a separate species.

Taxonomic source(s)
HBW and BirdLife International. 2017. Taxonomic checklist of the birds of the world. V2.0.
Kirwan, G. M. & Collar, N. J. C. 2016. The ‘foremost ornithological mystery of Costa Rica’: Amazilia alfaroana Underwood, 1896. Zootaxa 4189(2): 244-250.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
D	D	D1

Red List history

Year	Category	Criteria
2021	Critically Endangered	D
2017	Critically Endangered	D
2016	Not Recognised
2012	Not Recognised
2008	Not Recognised
2004	Not Recognised
2000	Not Recognised
1994	Not Recognised
1988	Not Recognised

Migratory status	unknown	Forest dependency	medium
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	80 km2	medium
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	1-49 mature individuals	medium	estimated	2016
Population trend	stable	-	suspected	-
Generation length	1.87 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: If the species persists, any remaining population is assumed to be tiny (<50 mature individuals; Kirwan and Collar 2016).

Trend justification: Recent forest loss at this locality has been minimal (Global Forest Watch 2016) and so any potential remaining population is suspected to be stable.

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

Country/Territory	IBA Name

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	600 - 650 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Livestock farming & ranching - Small-holder grazing, ranching or farming	Timing		Scope		Severity		Impact
		Past, Likely to Return		Unknown		Unknown		No/Negligible Impact: 0
		Stresses Ecosystem degradation, Ecosystem conversion

Purpose	Scale
Pets/display animals, horticulture	international

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Recommended citation
BirdLife International (2024) Species factsheet: Guanacaste Hummingbird Amazilia alfaroana. Downloaded from https://datazone.birdlife.org/species/factsheet/guanacaste-hummingbird-amazilia-alfaroana on 23/12/2024.
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 23/12/2024.