• 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., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.

Red List criteria met

Critically Endangered	Endangered	Vulnerable
-	-	D1+2

Red List history

Year	Category	Criteria
2020	Vulnerable	D1+2
2016	Vulnerable	D1+2
2012	Vulnerable	D1+2
2008	Vulnerable	D1; D2
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Vulnerable
1988	Threatened

Migratory status	not a migrant	Forest dependency	does not normally occur in forest
Land-mass type		Average mass	-

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	38 km2	medium
Number of locations	1	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	340-400 mature individuals	medium	estimated	2000
Population trend	stable	poor	suspected	1998-2008
Generation length	2.44 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The population is estimated to number 170-200 pairs, or 340-400 mature individuals and the species is apparently common throughout all of the island and around the naval garrison. According to recent data (Ortiz-Alcaraz et al. 2018), density estimates are 3.2 individuals/ha in the wet season and 6.55 individuals/ha in the dry season. Further population studies are needed.

Trend justification: There are recent counts but no new data on population trends. The introduced mammal that remains on Clarión is the European Rabbit and no evidence of negative impacts exists, aside from greatly slowing vegetation regrowth after a significant fire in the 1980s. Therefore, the population is currently suspected to be stable, although this warrants further investigation.

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

Country/Territory	IBA Name
Mexico	Islas Revillagigedo

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Rural Gardens	suitable	resident
Shrubland	Subtropical/Tropical Dry	major	resident
Altitude	0 - 335 m	Occasional altitudinal limits

Threat (level 1)	Threat (level 2)	Impact and Stresses
Climate change & severe weather	Habitat shifting & alteration	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Unknown		Unknown
		Stresses Indirect ecosystem effects, Ecosystem degradation
Climate change & severe weather	Storms & flooding	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Rapid Declines		High Impact: 8
		Stresses Indirect ecosystem effects, Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Very Rapid Declines		Medium Impact: 7
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Named species	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Very Rapid Declines		Medium Impact: 7
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Named species	Timing		Scope		Severity		Impact
		Future		Whole (>90%)		Very Rapid Declines		Medium Impact: 7
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Oryctolagus cuniculus	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Negligible declines		Medium Impact: 6
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Problematic native species/diseases - Athene cunicularia	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Reduced reproductive success
Invasive and other problematic species, genes & diseases	Problematic native species/diseases - Named species	Timing		Scope		Severity		Impact
		Ongoing		Unknown		Unknown		Unknown
		Stresses Reduced reproductive success
Natural system modifications	Fire & fire suppression - Trend Unknown/Unrecorded	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Rapid Declines		Medium Impact: 7
		Stresses Ecosystem degradation, Species mortality

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Recommended citation
BirdLife International (2024) Species factsheet: Clarion Wren Troglodytes tanneri. Downloaded from https://datazone.birdlife.org/species/factsheet/clarion-wren-troglodytes-tanneri 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.