• 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
-	-	-

Red List history

Year	Category	Criteria
2021	Near Threatened	C1
2016	Vulnerable	A2c+3c+4c;B1ab(i,ii,iii,v)
2012	Vulnerable	A2c+3c+4c;B1ab(i,ii,iii,v)
2008	Vulnerable	A2c; A3c; A4c; B1a+b(i,ii,iii,v)
2004	Vulnerable
2000	Vulnerable
1996	Endangered
1994	Endangered
1988	Threatened

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	25,100 km2	medium
Area of Occupancy (breeding/resident)	9,504 km2
Number of locations	6-10	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	6000-15000 mature individuals	poor	suspected	2000
Population trend	decreasing	poor	inferred	2014-2024
Rate of change over the past 10 years/3 generations (longer of the two periods)	3-13%	-	-	-
Rate of change over the future 10 years/3 generations (longer of the two periods)	3-13%	-	-	-
Rate of change over the past & future 10 years/3 generations (longer of the two periods)	3-13%	-	-	-
Generation length	2.4 years	-	-	-
Number of subpopulations	2-10	-	-	-
Percentage of mature individuals in largest subpopulation	1-89%	-	-	-

Population justification: The population size is preliminarily suspected to fall into the band 10,000-19,999 individuals. This equates to 6,667-13,333 mature individuals, rounded here to 6,000-15,000 mature individuals.

Trend justification: The species is undergoing a slow decline due to the loss and degradation of its montane forest habitat (Partners in Flight 2019; Arizmendi et al. 2020). Tree cover loss within the range has been low (1% over ten years; Global Forest Watch 2021). It has been hypothesised that 15-49% of the total population has been lost during the period 1970-2017, based on assessments of habitat loss (Partners in Flight 2019; Arizmendi et al. 2020). Assuming a constant rate of decline, this averages to a decline of 3-13% over ten years. In view of the ongoing threats, this is suspected to continue at a similar rate into the future.

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

Country/Territory	IBA Name
Mexico	Omiltemi
Mexico	Sierra de Atoyac y Bosques de Niebla de la Costa Grande
Mexico	Vallecitos de Zaragoza

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Plantations	suitable	non-breeding
Forest	Subtropical/Tropical Moist Lowland	suitable	resident
Forest	Subtropical/Tropical Moist Montane	major	resident
Altitude	800 - 2440 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Agriculture & aquaculture	Annual & perennial non-timber crops - Scale Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Slow, Significant Declines		Medium Impact: 6
		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
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Capra hircus	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		No decline		Low Impact: 4
		Stresses Ecosystem degradation

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Recommended citation
BirdLife International (2024) Species factsheet: White-tailed Hummingbird Eupherusa poliocerca. Downloaded from https://datazone.birdlife.org/species/factsheet/white-tailed-hummingbird-eupherusa-poliocerca on 22/11/2024.
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 22/11/2024.