Zieria chevalieri is a shrub endemic to the north-west of Grande Terre in New Caledonia. This species is only known subpopulation at Mount Kaala. The species is found in shrubland and humid forest on ultramafic substrates at an altitudinal range of 40-970 m asl. It could occur in forest on the northern slope of Mount Kaala. The main threats are linked to ongoing mining activities on Mount Kaala and bushfires at lower altitudes. Its extent of occurrence (EOO) and area of occupancy (AOO) are both estimated to be 12 km². Zieria chevalieri is therefore considered as Endangered (EN) under criteria B1ab(iii,v)+2ab(iii,v) with the number of locations estimated to be three.

Geographical area

Zieria chevalieri is an endemic shrub of the north-west of Grande Terre in New Caledonia. This species is only known at Mount Kaala.

Population

Population size is unknown but Zieria chevalieri seems to form quite dense subpopulations.

Habitat

Zieria chevalieri is found in shrubland and humid forest on ultramafic substrate at an altitudinal range 40-970 m asl. It could occur in forest on the northern slope of Mount Kaala.

Threats

The main threat is indirectly linked to ongoing mining activities on Mount Kaala that can contribute to the degradation of the habitat quality (erosion). New Caledonia contains 20 - 30% of the world’s nickel resources. Intense mining activities since the late 19th century have generated soil erosion (1.2% of bare ground mapped by SPOT5 in 2007). Based on the distribution of metal-rich soils and site accessibility, these threats are predictable and planned (there was a rise in nickel production from 60,000 to 200,000 tons per year between 2013 and 2015). Moreover, Mount Kaala is severely damaged by fire but this species does not seem to be affected at the moment.

Conservation

A protected species by legislation in Province Nord, Zieria chevalieri does not occur in any protected area. Through a partnership in 2015 with IAC (Institut Agronomique néo-Calédonien) research works focused on the species were conducted. This included monitoring, gathering cuttings, propagation tests and genetics study. Propagation through cuttings gave only a low rate of success (mortality rate of over 95%). Searches outside inventoried area are in progress. This species would benefit from ex situ and in situ emergency conservation actions. It is proposed to ensure further propagation tests in order to assist future planting operations and the monitoring of the only known population, to better estimate population size and to preserve a viable population within delimited perimeters on Mount Kaala. Prospection operations around Mount Kaala should be continued, including forest on the northern slope of Mount Kaala.

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.

Wulff AS, Hollingsworth PM, Ahrends A, Jaffré T, Veillon J-M, L’Huillier L, et al. 2013. Conservation Priorities in a Biodiversity Hotspot: Analysis of Narrow Endemic Plant Species in New Caledonia.

Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.

L'Huillier L.; Jaffré T. and Wulff A. 2010. Mines et Environnement en Nouvelle-Calédonie : les milieux sur substrats ultramafiques et leur restauration.

Experts

Assessor(s): Tanguy, V., Veillon, J., Amice, R., Barrière, R., Fleurot, D., Gailhbaud, P., Garnier, D., Suprin, B.

Reviewer(s): Vandrot, H.

Contributor(s): Wulff, A.

Facilitator(s): Tanguy, V., Chanfreau, S.