Taxonomy
Common name :
Le Gecko rayé de Poum
Poum Striped Gecko Red List Status -
Critically Endangered (CR) , assessed in 11/12/2017Protected species -
in Southern Province , in Northern Province
Description
Description:
A small relatively gracile species of gecko growing to a body length of 38mm, with a short tail 110% that of the body. It has moderately broad toes. The colour pattern on the body is typically mid brown above with a broad lighter brown median region, defined by a pale but dark edged dorsolateral stripes either side of the body and with pale white stripes over the hips.
Natural distribution:
Known only from Sommet Poum in the far north of the island.
Distribution within Province Nord: see above.
Habitat:
Maquis shrubland and closed forest patches.
Threats:
-
high level of threat to maquis shrubland through activities associated with mining leading to a decline in area, extent and quality habitat.
-
potentially high level of threat to maquis shrubland from of fire leading to a decline in area, extent and quality of maquis shrubland.
-
potentially high level of threat to closed forest populations with high infestation levels of introduced fire ants (Wasmannia auropunctata) causing significant declines in abundance.
Conservation Status: Critically Endangered
Dierogekko poumensis has an extremely restricted distribution (<100km2). The summit area of Sommet Poum has been extensively impacted by mining activity, and a mine is operational at the northern end of the massif. Maquis shrubland has undergone a decline in the extent and quality as a result of mining activities in the past and could be threatened by continuation and expansion of these activities in the near future. The small areas of closed forest habitat on the summit ridge are threatened by mining activities and by the presence of the Little Red Fire Ant which has heavily infested the maquis shrubland. The species has been identified as highly threatened (Bauer et al., 2006) and to meet the criteria to be categorised as Critically Endangered.
*Species occurring in localised areas of maquis shrubland are highly susceptible to catastrophic impact of wildfires, and require pro-active conservation management to deal with this potential threat.
Dierogekko poumensis is listed as Critically Endangered because it has a very restricted distribution, its habitat is severely fragmented, and there is continuing decline in its extent of occurrence, the extent and quality of its habitat and the number of mature individuals. A plan to mine the Poum plateau is well advanced and it will remove the entire top of the mountain.
Geographical area
Dierogekko poumensis is endemic to Province Nord, New Caledonia. It is known only from the Poum massif, northern Grande Terre. It occurs at elevations between 10 and 415 m. The extent of occurrence and the area of occupancy are estimated to be 16 km2.
Population
There are no data on population size and trends for Dierogekko poumensis. It is presumed to have suffered a significant reduction in population size and extent with habitat loss and degradation resulting from wildfires and past mining activities. However, this species is still locally abundant at some sites where good habitat remains.
Habitat
Dierogekko poumensis inhabits rocky maquis shrublands and low, closed-forest remnants. It is nocturnal and arboreal, sheltering beneath stones by day, and climbing into the vegetation at night.
Threats
The greatest threats to Dierogekko poumensis are the immediate plan to mine the entire plateau of the Poum massif for nickel during the coming decade, the loss and the degradation of the habitat from wildfires, the predation pressure from feral cats (Palmas 2017) and the colonization of the forest remnants by the introduced ant Wasmannia auropunctata. These ants are known to decimate lizard populations and lead to localized extinctions (Jourdan et al. 2000, 2001).
Conservation
Protected in Province Nord under Code de l'environnement de la Province Nord (Délibération No. 306-2008/APN, 24 October 2008) and in Province Sud under Code de l'environnement de la Province Sud (Délibération No. 25-2009/APS, 20 March 2009). This species is not present in any reserve and no conservation management is currently being undertaken.
Bibliography
Uetz, P. (ed.) 2017. The Reptile Database.
Bauer, A.M., Jackman, T., Sadlier, R.A., Whitaker, A.H. 2006. A revision of the Bavayia validiclavis group (Squamata: Gekkota: Diplodactylidae), a clade of New Caledonian geckos exhibiting microendemism. Proceedings of the California Academy of Sciences(57) , p.503–547.
Jourdan, H., Sadlier, R.A. and Bauer, A.M. 2001. Little Fire Ant Invasion (Wasmannia auropunctata) as a threat to New Caledonian lizards: Evidences from a sclerophyll forest (Hymenoptera: Formicidae). Sociobiology(38) , p.283-301.
Palmas, P., Jourdan, H., Rigault, F., Debar, L., De Meringo, H., Bourguet, E., Mathivet, M., Lee, M., Adjouhgniope, R., Papillon, Y. and Bonnaud, E. 2017. Feral cats threaten the outstanding endemic fauna of the New Caledonia biodiversity hotspot. Biological Conservation(214) , p.250-259.
IUCN 2021. The IUCN Red List of Threatened Species. Version 2021-2.
Jourdan, H., Sadlier, R.A. and Bauer, A.M. 2000. Premières observations sur les conséquences de l’invasion de Wasmannia auropunctata 1863 (Roger) sur les prédateurs supérieurs dans les écosystèmes Néo-calédoniens. Actes des collectes insectes sociaux(13) , p.121-126.
Experts
Assessor(s): Sadlier, R., Bauer, A., Jourdan, H., Astrongatt, S., Deuss, M., Duval, T., Bourguet, E., McCoy, S., Bouteiller, A., Lagrange, A.
Reviewer(s): Cox, N.
Contributor(s): Whitaker, A.
Facilitator(s): Lietar, J., Warimavute, G., Tanguy, V.