VU
Chatham Islands Snipe Coenocorypha pusilla



Taxonomy

Taxonomic note
Closely related to and sometimes considered conspecific with C. iredalei, C. huegeli and C. aucklandica, but differs from them in its much smaller size (effect size for male bill difference 6.63; score 3); somewhat coarser breast streaking than in morphologically closest nominate aucklandica (1); apparently (fide published sonagrams (Higgins and Davies 1996)) different song structure (accelerating where aucklandica does not) and calls (at least 3). Monotypic.

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - D2

Red List history
Year Category Criteria
2022 Vulnerable D2
2016 Vulnerable D2
2013 Vulnerable D2
2012 Vulnerable D2
2008 Vulnerable D2
2006 Vulnerable
2004 Vulnerable
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Lower Risk/Least Concern
Species attributes

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

Estimate Data quality
Extent of Occurrence (breeding/resident) 180 km2 medium
Area of Occupancy (breeding/resident) 40 km2 good
Number of locations 4 -
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 1800-2200 mature individuals medium estimated 2021
Population trend stable medium estimated -
Generation length 4.18 years - - -
Number of subpopulations 4 - - -
Percentage of mature individuals in largest subpopulation 1-89% - - -

Population justification: The population is estimated at c.900-1,100 pairs. Higgins and Davies (1996) estimated the population to number 700-800 pairs on Rangatira (South East) Island, possibly 200-250 pairs on Mangere Island and fewer than 50 pairs on Little Mangere Island and Star Keys. The population is thus estimated to fall within the range 1,800-2,200 mature individuals, roughly equating to 2,700-3,300 individuals in total. Since the population is considered to be stable (Robertson et al. 2021), historic population estimates are thought to remain applicable.

Trend justification: Although the historical range of this species was reduced as the result of the introduction of predators such as cats Felis catus and rats Rattus spp. (Higgins and Davies 1996, Roberts and Miskelly 2003), the population is considered to have been stable throughout the last three generations  based on census data (Robertson et al. 2013, 2017, 2021).


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
New Zealand extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
New Zealand Mangere
New Zealand Rangatira South East Island
New Zealand Star Keys Motuhope

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Temperate major resident
Grassland Temperate major resident
Altitude 0 - 287 m Occasional altitudinal limits  

Threats & impact
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
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Felis catus Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Gallirallus australis Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Competition, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Named species Timing Scope Severity Impact
Past, Likely to Return Minority (<50%) Slow, Significant Declines Past Impact
Stresses
Reduced reproductive success

Recommended citation
BirdLife International (2024) Species factsheet: Chatham Islands Snipe Coenocorypha pusilla. Downloaded from https://datazone.birdlife.org/species/factsheet/chatham-islands-snipe-coenocorypha-pusilla 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.