• 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
-	B1ab(iii)+2ab(iii)	B1ab(iii)+2ab(iii); D1+2

Red List history

Year	Category	Criteria
2020	Endangered	B1ab(iii)+2ab(iii)
2016	Endangered	B1ab(iii)+2ab(iii)
2014	Endangered	C2a(i,ii)
2012	Endangered	C2a(ii)
2008	Endangered	C2a(ii)
2004	Vulnerable
2000	Vulnerable
1996	Vulnerable
1994	Not Recognised
1988	Not Recognised

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

	Estimate	Data quality
Extent of Occurrence (breeding/resident)	6 km2	medium
Area of Occupancy (breeding/resident)	16 km2
Number of locations	2-5	-
Severely fragmented?	no	-

	Estimate	Data quality	Derivation	Year of estimate
Population size	250-2000 mature individuals	poor	suspected	2007
Population trend	decreasing	poor	suspected	-
Generation length	3.07 years	-	-	-
Number of subpopulations	1	-	-	-
Percentage of mature individuals in largest subpopulation	100%	-	-	-

Population justification: The species has been described as fairly common, but no censuses have been made (M. Booke in litt. 2012). The population was suspected to be c.2,000-3,000 individuals in 1998-1999, and 250-999 mature individuals in 2007 (E. Bell in litt. 2007). Therefore, it is here placed in the band 250 - 2000 mature individuals. The species has a very small range on one island, so there is likely to be just one subpopulation.

Trend justification: There are no quantitative data on population size and trends. In recent decades there has been an increase in the spread and range of Rose Apple (Syzigium jambos) which threatens the native Pitcairn vegetation (E. and D. Bell in litt. 2007). Pitcairn has been recently subject to several development proposals, and a new harbour has been constructed, reducing the habitat available for this species (C. Stringer in litt. 2016). The species's population size is therefore suspected to be declining as a result of habitat loss and degradation,

Country/Territory	Presence	Origin	Resident	Breeding visitor	Non-breeding visitor	Passage migrant
Pitcairn Islands (to UK)	extant	native	yes

Country/Territory	IBA Name
Pitcairn Islands (to UK)	Pitcairn Island

Habitat (level 1)	Habitat (level 2)	Importance	Occurrence
Artificial/Terrestrial	Rural Gardens	suitable	resident
Forest	Subtropical/Tropical Moist Lowland	major	resident
Shrubland	Subtropical/Tropical Moist	suitable	resident
Altitude		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
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 - Capra hircus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Negligible declines		Low Impact: 5
		Stresses Ecosystem degradation
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Felis catus	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Rattus exulans	Timing		Scope		Severity		Impact
		Ongoing		Majority (50-90%)		Unknown		Unknown
		Stresses Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases	Invasive non-native/alien species/diseases - Syzygium jambos	Timing		Scope		Severity		Impact
		Ongoing		Whole (>90%)		Unknown		Unknown
		Stresses Ecosystem degradation
Residential & commercial development	Commercial & industrial areas	Timing		Scope		Severity		Impact
		Ongoing		Minority (<50%)		Slow, Significant Declines		Low Impact: 5
		Stresses Ecosystem degradation, Ecosystem conversion

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Recommended citation
BirdLife International (2024) Species factsheet: Pitcairn Reed-warbler Acrocephalus vaughani. Downloaded from https://datazone.birdlife.org/species/factsheet/pitcairn-reed-warbler-acrocephalus-vaughani on 18/12/2024.
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 18/12/2024.