Taxonomy
Synonyms
Bocquillonia spinuligera AiryShawRed List Status -
Critically Endangered (CR) , assessed in 10/09/2015Protected species -
in Southern Province , in Northern Province
Bocquillonia castaneifolia is a shrub endemic to the north-west of Grande Terre in New Caledonia. This species is only known from one location at Tiébaghi. The species was also known from Ile Art from a single herbarium specimen which dated from 1975, but recent prospections at Belep did not manage to relocate this species. It is found in shrubland on ultramafic substrates at an altitudinal range of 400-600 m asl. The main threat is presented by ongoing mining development in Thiébaghi area. The twenty five year projection for mining operations indicates that most of individuals will disappear. Bocquillonia castaneifolia is therefore considered as Critically Endangered (CR) under criterion A4c with an inferred population reduction of more than 80% over three generations (75 years) starting in 1970 and projected to 2045; and under criteria B1ab(i,ii,iii,v) with only one single threat-defined location, a continuous decline of all concerned subcriteria and an extent of occurrence (EOO) and area of occupancy (AOO) both estimated to be of 24 km².
Geographical area
Bocquillonia castaneifolia is a shrub endemic to the north-west of Grande Terre in New Caledonia. This species is known from one location at Tiébaghi. The species was also known from Ile Art from a single herbarium specimen which dated from 1975, but recent searches did not manage to relocate this species.
Population
Population size is estimated to be greater than 250 mature individuals in Thiébaghi. However, the mining extraction projections for the coming 25 years suggest that there could be a significant reduction in the total population size.
Habitat
Bocquillonia castaneifolia is found in shrubland on ultramafic substrate at an altitudinal range of 400-600 m asl.
Threats
The main threat to this species is presented by ongoing mining development in the Thiébaghi area. The twenty five year projection for mining operations indicates that most individuals there will disappear. New Caledonia contains 20 - 30% of the world’s nickel resources and has experienced intense mining activities since the late 19th century which has 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 tonnes per year between 2013 and 2015).
Conservation
Bocquillonia castaneifolia is protected by legislation in Province Sud and Province Nord, but does not occur in any protected area. It is reported that conservation measures are implemented by SLN (Société le Nickel) in the Thiébaghi area. Planting operations have been conducted, but monitoring has stopped. Through a partnership in 2015 with IAC (Institut Agronomique néo-Calédonien), technical guidelines was drawn up, propagation tests were conducted and new monitoring was set-up. Prospection outside inventoried area are now in progress. This species would benefit from ex-situ and in-situ emergency conservation actions. It is proposed to conduct propagation tests in order to assist future planting operations and to carry out monitoring of the only known populations, to better estimate population size and to preserve a viable population within delimited perimeters at Tiébaghi. Prospection operations around Tiébaghi should be continue, including in the Pic Noir area.
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.
L'Huillier L.; Jaffré T. and Wulff A. 2010. Mines et Environnement en Nouvelle-Calédonie : les milieux sur substrats ultramafiques et leur restauration.
Endemia.nc 2016. Faune et Flore de Nouvelle-Calédonie.
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.
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): Chanfreau, S., Tanguy, V.