Taxonomy
Synonyms
Bikkia kaalaensis N.Hallé & JérémieRed List Status -
Endangered (EN) , assessed in 10/09/2015Protected species -
in Southern Province , in Northern ProvinceThiollierea kaalaensis is an endemic shrub of the north-western part of Grande Terre in New Caledonia. This species is only known from Kaala. It is found in shrubland on ultramafic substrate up to 898 m asl. The main threat is linked to ongoing mining activities on Mount Kaala. Extraction projections in the coming 25 years may mean that most individuals are affected. Thiollierea kaalaensis is assessed as Endangered (EN) under criterion A4c with an inferred population reduction of more than 50% over three generations (75 years) starting in 1970 and projected to 2045; and under criteria B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) with the number of threat-defined locations estimated to be four, a continuous decline of all concerned subcriteria and extent of occurrence (EOO) and area of occupancy (AOO) are both estimated to be of 28 km².
Geographical area
Thiollierea kaalaensis is an endemic shrub of the north-western part of Grande Terre in New Caledonia. This species is only known from Kaala.
Population
Population size is unknown. Mmining extraction projections for the coming 25 years could lead to a 50% reduction in the population and thus contribute to the potential reduction of the total population size.
Habitat
Thiollierea kaalaensis is found in shrubland on ultramafic substrates up to 898 m asl.
Threats
The main threat is linked to ongoing mining activities on Mount Kaala. 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).
Conservation
Thiollierea kaalaensis is protected by legislation in Province Nord and Province Sud (under the name Bikkia kaalensis), but does not occur in any protected area. This species would benefit from ex-situ and in-situ emergency conservation actions. It is proposed to preserve a viable population within delimited perimeters. It would be moreover advised to conduct propagation tests in order to assist future planting operations, and to prospect actively in the Kaala area.
Bibliography
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.
L'Huillier L.; Jaffré T. and Wulff A. 2010. Mines et Environnement en Nouvelle-Calédonie : les milieux sur substrats ultramafiques et leur restauration.
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.
Barrabé L., Mouly A., Lowry II P.P. & Muzinger J. 2011. Reinstatement of the endemic New Caledonian genus Thiollierea Montrouz. (Rubiaceae) necessitated by the polyphyly of Bikkia Reinw. as currently circumscribed. Adansonia(33) , p.115-134.
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.