CR (PE)
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.
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 B1ab(ii,iii); D B1ab(ii,iii); D1+2

Red List history
Year Category Criteria
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) 270 medium
Number of locations 1 -
Fragmentation -
Population and trend
Estimate Data quality Derivation Year of estimate
No. of mature individuals 1-49 poor estimated 2016
Population trend Unknown poor -
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 - - -
Generation length (yrs) 4.4 - - -

Population justification: The species has been considered extinct (Dyrz and de Juana 2016), but there have been at least two unconfirmed reports since 2000 (A. Gouni in litt. 2007, Cibois et al. 2008, A. Gouni in litt. 2011). The lack of any definitive reports suggest that, if it is extant, the population size is likely very low (probably less than 50 mature individuals).

Trend justification: The lack of recent confirmed records prevent an assessment of population trend: it is possibly extinct.


Country/territory distribution
Country/Territory Occurrence status Presence Resident Breeding Non-breeding Passage
French Polynesia N Possibly Extinct 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 0 - 1700 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Marine & freshwater aquaculture Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Gathering terrestrial plants Timing Scope Severity Impact
Ongoing Majority (50-90%) Very Rapid Declines High Impact: 8
Stresses
Species disturbance, Ecosystem degradation, Reduced reproductive success
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Species disturbance, Ecosystem degradation, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases 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 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 Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases Timing Scope Severity Impact
Ongoing Majority (50-90%) Negligible declines Low Impact: 5
Stresses
Reduced reproductive success
Transportation & service corridors Roads & railroads Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion, Species mortality

Recommended citation
BirdLife International (2019) Species factsheet: Acrocephalus longirostris. Downloaded from http://www.birdlife.org on 24/08/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 24/08/2019.