VU
Tahiti Reed-warbler Acrocephalus caffer



Taxonomy

Taxonomic note

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

 

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.

IUCN Red list criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - D1

Red List history
Year Category Criteria
2020 Vulnerable D1
2016 Endangered B1ab(ii,iii,v);C2a(i)
Species attributes

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

Estimate Data quality
Extent of Occurrence breeding/resident (km2) 420 medium
Extent of Occurrence breeding/resident (km2) 456
Number of locations 19-100 -
Severely Fragmented -
Population and trend
Value Data quality Derivation Year of estimate
No. of mature individuals 250-999 poor estimated 2018
Population trend Stable poor estimated -
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 - - -
Percentage in largest subpopulation 100 - - -

Population justification: The population was estimated to number a few hundred individuals by Monnet et al. (1993). Surveys in 2017-18 recorded a minimum of 181 breeding territories and estimated at least 372 adults, noting that they were unable to access all valleys where the species was previously recorded (Lazzari et al. 2018, SOP Manu 2019). The population size is placed in the band 250-999 mature individuals.

Trend justification: Surveys have been carried out in 39 valleys during 1986-91 (Monnet et al. 1993) and during 2017-18 (Lazzari et al. 2018, SOP-Manu 2019). The 1986-91 surveys recorded the species in 12 valleys and estimated the population to number a few hundred individuals (Monnet et al. 1993). The 2017-18 surveys detected the species in 19 valleys, including several valleys where the species was previously reported to be absent, and estimated a population size of at least 372 adults (Lazzari et al. 2018, SOP-Manu 2019). Due to access limitations, the 2017-18 survey did not cover one of the valleys previously surveyed, but all resurveyed valleys that were previously occupied were still occupied (SOP-Manu 2019). The 2017-2018 survey appeared to show a territorial expansion, but differences in survey methodologies, including the use of playback in the later survey, mean that the trend is uncertain and is precautionarily hypothesised to be stable (SOP-Manu 2019).


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
French Polynesia Vallée de la Papenoo

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 50 - 700 m Occasional altitudinal limits (max) 1700 m

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Biological resource use Gathering terrestrial plants - Unintentional effects (species is not the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) No decline Low Impact: 5
Stresses
Species disturbance, Ecosystem degradation, Reduced reproductive success
Human intrusions & disturbance Recreational activities Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Acridotheres tristis Timing Scope Severity Impact
Ongoing Whole (>90%) No decline Medium Impact: 6
Stresses
Competition
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
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%) No decline Low Impact: 5
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%) No decline Low Impact: 4
Stresses
Competition
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Rattus rattus Timing Scope Severity Impact
Ongoing Majority (50-90%) No decline Low Impact: 5
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Wasmannia auropunctata Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
Stresses
Species disturbance, Ecosystem degradation, Reduced reproductive success
Transportation & service corridors Roads & railroads Timing Scope Severity Impact
Ongoing Minority (<50%) No decline Low Impact: 4
Stresses
Species disturbance, Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2022) Species factsheet: Acrocephalus caffer. Downloaded from http://www.birdlife.org on 28/09/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 28/09/2022.