||Gymnomyza aubryana (Verreaux & Des Murs, 1860)
||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.
||41cm. Very large, crow-like honeyeater with orange facial wattles. Plumage all glossy black, bill grey above and yellow below, legs yellow and facial skin varies from yellow to red. Long rounded wings and fairly long neck and tail. Similar spp. New Caledonian Crow Corvus moneduloides and Melanesian Cuckoo-shrike Coracina caledonica have short dark bills and no bare facial skin - crow has short tail and cuckoo-shrike has long pointed wings. Voice Loud, repeated series of slightly varied phrases, typically a loud nasal note e.g. chong, followed by a descending series, e.g. tchku-tchku-... Harsh scolding tcharr or wa-wa similar to parrot or crow. Hints Listen at dawn.
|Red List Category & Criteria:
||Butchart, S. & Symes, A.
||Barré, N., Chartendrault, V., Dutson, G., Ekstrom, J., Létocart, Y., Meresse, C., Meriot, J., O'Brien, M., Sirgouant, S., Spaggiari, J., Theuerkauf, J. & Stirnemann, R.
||Benstead, P., Bird, J., Derhé, M., Dutson, G., Ekstrom, J., Harding, M., Mahood, S., Stattersfield, A. & Ashpole, J
This species is listed as Critically Endangered because it is believed to have an extremely small population, almost confined to one area in the south-east of New Caledonia. Its population trend is poorly-known but assumed to be declining because of forest degradation largely through an increase in anthropogenic fires.
|Previously published Red List assessments:|
- 2015 – Critically Endangered (CR)
- 2013 – Critically Endangered (CR)
- 2012 – Critically Endangered (CR)
- 2009 – Critically Endangered (CR)
- 2008 – Endangered (EN)
- 2004 – Endangered (EN)
- 2000 – Endangered (EN)
- 1996 – Vulnerable (VU)
- 1994 – Vulnerable (VU)
- 1988 – Lower Risk/least concern (LR/lc)
|Range Description:||The species is endemic to New Caledonia (to France) where it is now mainly restricted to small populations scattered throughout the south of the island plus the Mt Panié massif in the north (Baudat-Franceschi 2013, Okahisa et al. 2016). Extensive surveys in 2001-2012 found the species at 81 locations (Chartendrault and Barré 2005, 2006, Okahisa et al. 2016). The total area where the bird has been recorded was estimated at <400 km2 (Létocart 2006) but a habitat suitability model suggests that 700 km2 is suitable habitat (Okahisa et al. 2016). It appears to be localised and uncommon even in favoured areas, although c.18 pairs were known in the study area of Rivière Bleue, each occupying c. 1 km2 of forest, potentially extrapolated to 160 pairs across this protected area (Y. Létocart in litt. 1999). This estimate has been considered over-optimistic (N. Barré in litt. 1999), particularly if pairs require c. 1 km2, and may not be representative of the density elsewhere (Chartendrault and Barré 2005, 2006). Based on this home-range of 1 km2 per pair and habitat modelling suggesting 700 km2 of suitable habitat, the total population is likely to be around 315–700 breeding pairs (Okahisa et al. 2016). This is lower than Ekstrom et al. (2002)'s suggestion of approximately 1000–3000 individuals which was based upon the assumption that all forests on ultramafic substrates provided suitable habitat for the species. A more precautionary but empirically-based estimate is 92 pairs within the Massif du Sud KBA (Angin 2011) plus a very few additional pairs scattered to the north.|
|♦ Continuing decline in area of occupancy (AOO):||Yes|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||9900|
|♦ Continuing decline in extent of occurrence (EOO):||Unknown||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Number of Locations:||11-100||♦ Continuing decline in number of locations:||Yes|
|♦ Extreme fluctuations in the number of locations:||No|
|♦ Upper elevation limit (metres):||1000|
|Range Map:||Click here to open the map viewer and explore range.|
Forest loss and degradation caused by logging, nickel mining and fires is likely to be a threat (Ekstrom et al. 2000, 2002), potentially having had a considerable impact in the côté oubliée from where the species now appears to be absent (V. Chartenrauldt in litt. 2009). The apparent decline at Rivière Bleue must be caused by other factors; with the species apparently subjected to severe predation pressure by introduced rats Rattus spp.(Ekstrom et al. 2002, N. Barré in litt. 2003, Létocart 2006) and possibly cats Felis catus (R. Stirnemann in litt. 2012). No successful nests or juvenile birds were seen until 2004 at Rivière Bleue, suggesting that the limiting factor affects its breeding success (Y. Létocart in litt. 1999). However, in 2004 and 2005, two chicks fledged successfully and were tracked visually for a few days. Nesting areas were heavily poisoned for rat population control which may explain the nesting success but another nest, found in 2005, and also in an area where rats were controlled failed with the chick disappearing during the first week (Létocart 2006). Other possible nest predators include native endemic predators such as New Caledonian Crow (Corvus moneduloides), White-bellied Goshawk (Accipiter haplochrous), New Caledonian Giant Gecko (Rhacodactylus leachianus), Swamp Harrier (Circus approximans) and Peregrine Falcon (Falco peregrinus) (Baudat-Franceschi 2013); nests are poorly camouflaged and presumably easy to locate (Létocart 2006). One of the two chicks visually monitored after fledging was usually moving between trees on the forest floor, this could mean that the species is also vulnerable to cats, dogs and pigs (Létocart 2006). Grazing of understory vegetation by Rusa Deer (Cervus timorensis) may reduce habitat quality for the species (Baudat-Franceschi 2013). Forestry operations pose a threat as access roads allow the spread of invasive species, fire and hunters (Baudat-Franceschi 2013). Given the very small population size, hunting is also a potential threat. The species may be susceptible to avian malaria.