Taxonomy
Red List Status -
Critically Endangered (CR) , assessed in 03/07/2017Protected species -
in Southern Province , in Northern Province
Araucaria nemorosa is endemic to New Caledonia. This species is assessed as Critically Endangered due to severe fragmentation of the population, its very small extent of occurrence (EOO = 32 km²), and continuing decline in range, habitat and population size. The total population is smaller than 5,000 mature individuals, occurring within two locations. More than 90% of the population is found within seven fragments around Port Boisé, while the remaining 10% occurs slightly inland at Forêt Nord, where a smelter is being developed. This area is the focus of an ongoing restoration programme. Subpopulations in the immediate vicinity of Port Boisé are primarily threatened by fire. Genetic research indicates high levels of inbreeding as a result of fragmentation.
Geographical area
This species is endemic to the Port Boisé area in southern New Caledonia, occurring from sea level to 200 m asl.
Population
The total population size is estimated to be smaller than 5,000 mature individuals. More than 90% of the population occurs in seven small fragments in the Port Boisé area. The remaining 10% occurs in a small fragment known as Forêt Nord, several kilometres inland. Ecological surveys indicate that this species was more widespread, but has undergone significant reduction in the recent past. There is evidence of inbreeding throughout the population.
Habitat
The main population of this species occurs on a level plateau just inland from Port Boisé at around 20–40 m asl. The trees stand in small groups or wide apart among low (to 10 m) and open to dense evergreen forest or scrub, interspersed with nearly black, stony areas (cuirasse) almost devoid of vegetation.
Threats
Around Port Boisé it is vulnerable to increasing widlfires, occasional felling and the expansion of human habitation. At Forêt Nord the subpopulation is within the mining development of VALE NC. Recent research has indicated that all subpopulations are showing signs of inbreeding.
Conservation
The subpopulation at Forêt Nord is in a fenced area (built in 2005) in order to protect it from physical impacts linked to the mining project. Structural and genetic studies (Kettle et al. 2007, 2008) has shown that the genetic diversity of this species is declining and inbreeding is a problem.
Bibliography
Morat, P.; Jaffré, T.; Tronchet, F.; Munzinger, J.; Pillon, Y.; Veillon, J.-M. and Chalopin, M. 2012. Le référentiel taxonomique Florical et les caractéristiques de la flore vasculaire indigène de la Nouvelle-Calédonie [The taxonomic database « FLORICAL » and characteristics of the indigenous flora of New Caledonia]. Adansonia sér 3(34) , p.177-219.
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
Kettle, C.J., Ennos, R., Jaffré, T., Gardner, M. and Hollingsworth, P.M. 2008. Cryptic genetic bottlenecks during restoration of an endangered tropical conifer.. Biological Conservation(141) , p.1953-1961.
Jaffré, T., Munzinger, J. & Lowry, P.P. 2010. Threats to the conifer species found on New Caledonia’s ultramafic massifs and proposals for urgently needed measures to improve their protection.. Biodiversity and Conservation (19) , p.1485-1502.
Jaffré, T., Bouchet, P. and Veillon, J.-M. 1996. Threatened plants of New Caledonia: Is the system of protected areas adequate?. Biodiversity and Conservation (7(1)) , p.109-135.
de Laubenfels, D.J. 1972. Flore de la Nouvelle-Calédonie et dépendances..
Kettle, C.J., Hollingsworth, P.M., Jaffré, T., Moran, B. and Ennos, R.A. 2007. Identifying the early genetic consequences of habitat degradation in a highly threatened tropical conifer, Araucaria nemorosa de Laub.. Molecular Ecology(16) , p.3581-3591.
Munzinger J., Morat Ph., Jaffré T., Gâteblé G., Pillon Y., Rouhan G., Bruy, D., Veillon J.-M., & M. Chalopin 2020. FLORICAL: Checklist of the vascular indigenous flora of New Caledonia [continuously updated].
Experts
Assessor(s): Amice, R., Cazé, H., Dumontet, V., Fleurot, D., Garnier, D., Héquet, V., Lagrange, A., Lannuzel, G., McCoy, S., Suprin, B., Veillon, J.
Reviewer(s): Gardner, M., Jaffré, T., Thomas, P., Munzinger, J.
Contributor(s): Butaud, J., Gueugnier, C.
Facilitator(s): Tanguy, V., Maura, J.