Syzygium koumacense is an endemic shrub or small tree up to 12 m tall restricted to a single continuous calcareous outcrop close to Koumac, in the north west part of Grande Terre. It is found in mesophyllis forest on calcareous cliffs at an elevation of 30-312 m asl. Main identified threats, linked to habitat damage by Rusa deer (Rusa timorensis) and bushfires, allow us to project a continuous decline in the quality of habitat and number of mature individuals. Its extent of occurrence (EOO) and area of occupancy (AOO) are both estimated to be of 20 km² while the species is known from a single continuous calcareous outcrop. S. koumacense is therefore assessed as Critically Endangered (CR) B1ab(iii,v).

Geographical area

S. koumacense is an endemic shrub or small tree up to 12 m tall restricted to a single continuous calcareous outcrop close to Koumac, in the north west part of Grande Terre.

Population

Population size is unknown but field observations indicate a good regeneration that result to small populations in its mature state, due to deer's impacts.

Habitat

S. koumacense is occurs in mesophyllis forest on calcareous cliffs at an elevation of 30-312 m asl.

Threats

Main identified threats are linked to habitat damage by Rusa deer (Rusa timorensis) that destroy the juveniles and bushfires.

Conservation

Unprotected by legislation, S. koumacense does not occur in any protected areas. This species should be included in the regional legislation for a better protection of the species and ex situ and in situ conservation efforts are urgently needed, in particular : ensuring the follow-up of the known sub-populations and preserving it on delimited perimeters. It is moreover recommended to prospect calcareous outcrop around Koumac. It is recommended to inform the local authority responsible for the coordination of the firefighting effort about the presence of the species in the concerned areas.

Bibliography

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

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.

Dawson J.W. 1999. Flore de la Nouvelle-Calédonie et dépendances. Volume 23 : Myrtaceae Myrtoideae 1 : Syzygium.

Experts

Assessor(s): Héquet, V., Vandrot, H., Barrabé, L., Amice, R., Butin, J., Cazé, H., Fleurot, D., Suprin, B., Chambrey, C., Laudereau, C., Haverkamp, C., Fogliani, B.

Reviewer(s): Gâteblé, G.

Facilitator(s): Tanguy, V., Meyer, S., Warimavute, G.