VU
Chatham Snipe Coenocorypha pusilla



Justification

Justification of Red List Category
This species is confined to only four predator-free islands, and has a very small overall range. As such, the accidental introduction of alien species could easily cause its local extinction, and it is therefore classified as Vulnerable.

Population justification
Higgins and Davies (1996) estimated the population to number 700-800 pairs on 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.

Trend justification
Although the historical range of the species was reduced by introduced predators, it now appears to be stable.

Distribution and population

Coenocorypha pusilla is confined to four small, predator-free islands in the Chatham Islands, New Zealand, where it is common and considered stable. It was once widespread throughout the group. The population is estimated at c.900-1,100 pairs. Most of these, 700-800 pairs, are on Rangatira (=South East) Island. The population on Mangere Island (which was reintroduced from Rangatira Island) numbers between 200 and 250 pairs. Birds have recently colonised Little Mangere Island, and a population was recently found on Star Keys (totalling fewer than 50 pairs) (Higgins and Davies 1996, Aikman and Miskelly 2004). Vagrant individuals have been seen on Pitt Island and nearby Rabbit Island (Miskelly et al. 2006).

Ecology

It breeds from the shore to island summits, but is most common in Plagianthus chathamicus and Olearia traversi forest. It builds its nests under dense vegetation, and usually lays two eggs (Miskelly 1990, 1999a). It is insectivorous (Higgins and Davies 1996). Its age of first breeding and life expectancy are unknown, but other Coenocorypha snipe can breed at one year of age, and live for up to 17 years (Miskelly 1999b, Miskelly and Sagar 2005).

Threats

The historical range of this species was reduced as the result of the introduction of predators such as cats and rats Rattus spp. (Higgins and Davies 1996, Roberts and Miskelly 2003). Birds attempting to colonise neighbouring Pitt Island are killed by cats and Weka Gallirallus australis (introduced following the species extirpation from the main Chatham islands) (C. Miskelly pers. comm.).

Conservation actions

Conservation Actions Underway
In 1970, the species was successfully reintroduced from Rangatira Island to Mangere Island, after feral cats were eradicated (Aikman and Miskelly 2004). Captive breeding was attempted in 1983 and 1987, but failed (Heather and Robertson 1997, Aikman and Miskelly 2004). However, in 2001 a trial attempt to hold the species in captivity was successful (Miskelly and Barlow 2001).

Conservation Actions Proposed
Monitor population trends through regular surveys. Reintroduce the species to the predator-fenced portion of Ellen Elizabeth Preece Conservation Covenant on Pitt Island (Colin Miskelly pers. comm., Aikman et al. 2001, Roberts and Miskelly 2003, Aikman and Miskelly 2004).  Develop the captive breeding population to aid in this and future reintroductions and supplementation efforts.  Restore sufficient mammal-free forest areas within the Chatham Islands to allow the species to establish self-sustaining populations that require minimal management (Aikman et al. 2001, Roberts and Miskelly 2003, Aikman and Miskelly 2004).

Identification

20 cm. Small, compact, variegated brown snipe. Top of head striped black, brown/reddish-brown. Rest of body mottled black, brown/reddish-brown except for pale lower breast, belly. Voice Male call, low trerk, trerk, trerk and queeyoo, queeyoo, queeyoo.

Acknowledgements

Text account compilers
Benstead, P., Khwaja, N., Mahood, S., McClellan, R., Pilgrim, J., Taylor, J.

Contributors
Miskelly, C., Bell, B.


Recommended citation
BirdLife International (2022) Species factsheet: Coenocorypha pusilla. Downloaded from http://www.birdlife.org on 16/05/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/05/2022.