CR
Moorea Reed-warbler Acrocephalus longirostris



Taxonomy

Taxonomic note

Acrocephalus caffer, A. musae and A. longirostris (del Hoyo and Collar 2016) were previously lumped as A. caffer following Sibley & Monroe (1990, 1993).

Taxonomic source(s)
Cibois, A.; Thibault, J.-C.; Pasquet, E. 2008. Systematics of the extinct reed warblers Acrocephalus of the Society Islands of eastern Polynesia. Ibis 150(2): 365-376.
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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
D D D1+2

Red List history
Year Category Criteria
2019 Critically Endangered D
2018 Critically Endangered D
2016 Critically Endangered D
Species attributes

Migratory status not a migrant Forest dependency Medium
Land mass type Average mass -
Extent of occurrence (EOO)

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 204 medium
Extent of Occurrence breeding/resident (km2) 204
Number of locations 1 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 1-49 poor suspected 2016
Population trend Unknown poor not applicable -
Decline (3 years/1 generation past) - - -
Decline (5 years/1 generation past) - - -
Decline (10 years/1 generation past) - - -
Decline (10 years/3 generation future) - - -
Decline (10 years/3 generation past and future) - - -
Number of subpopulations 1 - - -
Largest subpopulations 100 - - -
Generation length (yrs) 4.4 - - -

Population justification: The lack of any confirmed recent reports suggests that the population size is likely very low (probably less than 50 mature individuals).

Trend justification: There is no evidence to indicate that the species's area of habitat is declining, but the lack of recent confirmed records and lack of knowledge about the reasons for the species's past decline prevent an assessment of the current population trend.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
French Polynesia N Extant Yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Terrestrial Plantations suitable resident
Forest Subtropical/Tropical Moist Lowland major resident
Shrubland Subtropical/Tropical Moist major resident
Altitude 300 - 600 m Occasional altitudinal limits (max) 1700 m

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Marine & freshwater aquaculture - Scale Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Gathering terrestrial plants - Unintentional effects (species is not the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Species disturbance, Ecosystem degradation, Reduced reproductive success
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Species disturbance, Ecosystem degradation, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Acridotheres tristis Timing Scope Severity Impact
Ongoing Whole (>90%) Unknown Unknown
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Miconia calvescens Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Pycnonotus cafer Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Majority (50-90%) Unknown Unknown
Stresses
Reduced reproductive success
Transportation & service corridors Roads & railroads Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion, Species mortality

Recommended citation
BirdLife International (2020) Species factsheet: Acrocephalus longirostris. Downloaded from http://www.birdlife.org on 21/01/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/01/2020.