Pittosporum aliferum is an endemic shrub of New Caledonia restricted to massifs of Boulinda and Kopéto. A riparian species, P. aliferum occurs in humid forest on ultramafic soils from 100 to 800 m asl. Its area of occupancy (AOO) is equal to 32 km² for an extent of occurrence (EOO) of 159 km². A total of 4 locations are affected by mining activities. The combined threats of fire, invasive animal species such as the rusa deer (Rusa timorensis) and the major threat of mining activities, allows us to infer a continuous decline of AOO, EOO, quality of habitat, number of locations and number of mature individuals. Using criteria B, P. aliferum qualifies for Endangered (EN) B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v).

Geographical area

Pittosporum aliferum is an endemic shrub of New Caledonia restricted to massifs of Boulinda and Kopéto.

Population

The precise population size is unknown, but due to its ecology, this one could reach 2,500 mature individuals.

Habitat

A riparian species, P. aliferum occurs in humid forest and on forest edges on ultramafic soils from 100 to 800 m asl.

Threats

On Boulinda and Kopeto, past and future mining activities form the primary threat, especially with the potential reopening of the mine on Boulinda. New Caledonia contains between 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). Fire constitutes a potential threat on Boulinda and Petit Boulinda summits, and on Ouaté locality. Erosion has also been observed on Ouaté, which could affect the population of P. aliferum. Finally rusa deer (Rusa timorensis), a major invasive species in New Caledonia, constitutes a potential threat to regeneration of the population via grazing of seedlings.

Conservation

P. aliferum is protected by legislation in Province Nord and Province Sud. Nevertheless, this species is not found in any protected areas. In order to assure survival of this species, it should be protected (by fencing from deer) on Boulinda. In order to advance knowledge on New Caledonian species of Pittosporum species, and especially the relatedness of P. aliferum and P. collinum, further research, such as fine-scale phylogenetic and ecological studies, is urgently required.

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.

Hély-Alleaume 2012. INC : Incendies et biodiversité des éco-systèmes en Nouvelle-Calédonie.

Tirel, C. & Veillon J.-M. 2002. Flore de la Nouvelle-Calédonie et dépendances. Volume 24 : Pittosporaceae.

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.

Gomez C.; Mangeas M.; Curt T.; Ibanez T.; Munzinger J.; Dumas P.; Jérémy A.; Despinoy M. and Hély C. 2014. Wildfire risk for main vegetation units in a biodiversity hotspot: modeling approach in New Caledonia, South Pacific. Ecology and Evolution(5) , p.377-390.

Experts

Assessor(s): Gemmill, C., Veillon, J., Amice, R., Cazé, H., Dumontet, V., Fleurot, D., Garnier, D., Gâteblé, G., Maggia, L.

Reviewer(s): Tanguy, V.

Facilitator(s): Chanfreau, S.