Agathis montana is a long lived conifer (generation length may be ca 500 years) restricted to the higher elevations of the Mt Panié range in Province Nord, New Caledonia where it occurs on three summits (Mt Panié, Mt Colnett and Mt Ignambi). The extent of occurrence (EOO) is estimated to be 73 km2 and the area of occupancy (AOO) to 36 km2. Population decline and habitat degradation have been observed over the last eight years in the subpopulation on the summit of Mt Panié and are projected to continue. The two other subpopulations (Mt Colnett and Mt Ignambi) are little known and need to be investigated to see if similar decline is occurring or likely to occur. Agathis montana is therefore considered Endangered based on occurrence at two threat-defined locations under criteria B1 and B2. Twenty per cent of the trees within the area of a monitoring programme are already dead: 5% of mature monitored trees died between October 2012 and February 2014, suggesting a projected population reduction of 80% within the next 21 years and a likelihood of there being no mature trees left in 100 years. An assessment under Criterion A4 was considered but has not been used due to the small sample size and the limited time period for which the situation has been monitored. The Colnett and Ignambi massifs are especially difficult to access and their summits have hardly been visited in the past decades. Several factors may be contributing to the decline and habitat degradation. Foraging invasive pigs disturb soil leading to increased erosion of the thin and vulnerable soil as well as the death of the fine feeder roots of the kauri trees causing stress. Feral pigs are also known to be vectors of pathogens which may be attacking the weakened trees. A Phytophthora species with affinities to the one linked to extensive dieback of New Zealand Agathis australis has been recorded on A. montana trees that are showing evidence of decline. Recorded increases in temperature and potentially altered cloud regime may lead to an increase in water stress to which A. montana is particularly susceptible. Recent regional droughts, concurrent with the recorded increase in temperatures and combined with the impact of feral pigs and Phytophthora may be jointly causing the decline. Conservation management includes pig control and was due to start in 2015. Further research into other causes of the decline is needed, as well as surveys on Mts Colnett and Ignambi to better appreciate the state of this species' subpopulations.

Aire géographique

Confiné au massif du Panié de 1000 à 1600m d'altitude

Population

3 sous-populations : Ignambi, Colnett, Panié

Habitat

Arbre émergent de forêt d'altitude sur substrat volcano-sédimentaire

Menaces

Cochons, pathogènes, stress hydrique, cf étude CI/Dayu

Conservation

Espèce présente dans 1 réserve(s) : Mont Panié

Bibliographie

Conservation International. 2011. Delineation of Key Biodiversity Areas in New Caledonia. Noumea..

Maitrepierre L. and Caudmont, S. 2007. Atlas climatique de la Nouvelle-Calédonie. Météo-France - Direction interrégionale en Nouvelle-Calédonie et à Wallis-et- Futuna. Nouméa.

Krull, C.R., Waipara, N.W., Choquenot, D., Burns, B.R., Gormley, A.W. and Stanley, M.C. 2012. Absence of evidence is not evidence of absence: Feral pigs as vectors of soil-borne pathogens. Austral Ecology(38(5)) , p.534-542.

Munzinger J., Morat Ph., Jaffré T., Gâteblé G., Pillon Y., Rouhan G., Bruy, D., Veillon J.-M., & M. Chalopin 2020. FLORICAL: Checklist of the vascular indigenous flora of New Caledonia [continuously updated].

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.

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

Farjon, A. 2019. Herbarium records from the World Conifer Database.

Jaffré, T., Bouchet, P. and Veillon, J.-M. 1996. Threatened plants of New Caledonia: Is the system of protected areas adequate?. Biodiversity and Conservation (7(1)) , p.109-135.

Jaffré, T., Munzinger, J. & Lowry, P.P. 2010. Threats to the conifer species found on New Caledonia’s ultramafic massifs and proposals for urgently needed measures to improve their protection.. Biodiversity and Conservation (19) , p.1485-1502.

Manauté, J., Jaffré, T., Veillon, J.-M. and Kranitz, M. 2003. Revue des Araucariaceae de Nouvelle-Calédonie. IRD, Nouméa..

Anonyme 2011. Plan de gestion de la Réserve de nature sauvage du Mont Panié..

Brodribb, T. and Delzon, S. 2015. Mt Panié Kauri (Agathis montana) vulnerability to water stress..

Casola, J. and Tron, F. 2013. Interannual precipitation and temperature variability near Mt. Panié wilderness reserve and its connection to kauri (Agathis montana) die-back. In: F.M. Tron, R. Franquet, T.H. Larsen and J.J. Cassan (eds).

Mazur, M.A., Tron, F. and Mille, C. 2017. Pactola kuscheli sp. nov. (Coleoptera: Curculionidae), a potential cause for the decline of the threatened New Caledonian conifer, Agathis montana de Laubenfels, 1969 (Araucariaceae).. Austral Entomology(56) , p.268-276.

Enright, N.J., Ogden, J. and Rigg, L.S. 1999. Dynamics of forests with Araucariaceae in the western Pacific.. Journal of Vegetation Science(10) , p.793-804.

GNS Science. 2012. Radiocarbon calibration report for Conservation International New Caledonia..

Grandcolas, P., Murienne, J., Robillard, T. and Desutter-Grandcolas, L., Jourdan, H., Guilbert E. and Deharveng, L. 2008. New Caledonia: a very old Darwinian island?. Philosophical Transactions of the Royal Socety B(363) , p.3309-3317.

Jaffré, T. and Munzinger 2009. Conservation status of Araucaria schmidii and Agathis montana. Email correspondence with IUCN SSC Conifer RLA Focal Point..

Jaffré, T., Morat, Ph., Veillon, J.-M. and MacKee, H.S 1987. Changements dans la végétation de la Nouvelle-Calédonie au cours du Tertiaire: la végétation et la flore des roches ultrabasiques.. Bulletin du Museum National d'Histoire Naturelle. 4e Serie. Section B. Adansonia (9) , p.365-391.

Wulff, A. 2012. Le micro-endémisme dans un hotspot de biodiversité: approche globale sur la flore vasculaire de la Nouvelle-Calédonie et analyse comparative au sein du genre Scaevola. Thèse de doctorat de, l’Université de la Nouvelle-Calédonie..

Waipara, N. 2012. Preliminary symptomology assessment of Agathis montana dieback at Mont Panié Wilderness Reserve - A report from a field visit support, July 10-18, 2012..

Tron, F. and Sabran, S. 2014. Agathis montana. The IUCN Red List of Threatened Species 2014(1): e.T30978A59535519..

Thomas, P. 2010. Agathis montana. The IUCN Red List of Threatened Species 2010(3): e.T30978A9597044..

Texier, N. 2013. Caractérisation du peuplement et de la mortalité d’Agathis montana de Laubenfels (Araucariaceae) au sein de la réserve de nature sauvage du Mont Panié, Province nord, Nouvelle Calédonie : approche architecturale et écologique. Rapport de stage M2 AMAP..

Sabran, C. and Tron, F. 2014. Dépérissement des Kaoris (Agathis montana) du Mont Panié. Bilan du suivi de février. Rapport de mission Dayu Biik & Conservation International..

Munzinger, J. 2013. Inventaire botanique du massif du Panié et des Roches de la Ouaième, province Nord, Nouvelle-Calédonie. In: F.M. Tron, R. Franquet, T.H. Larsen and J.J. Cassan (eds),.

Experts

Assessor(s): Amice, R., Cazé, H., Dumontet, V., Fleurot, D., Garnier, D., Héquet, V., Lagrange, A., Lannuzel, G., McCoy, S., Suprin, B., Veillon, J.

Reviewer(s): Jaffré, T., Munzinger, J., Thomas, P., Gardner, M.

Contributor(s): Butaud, J., Gueugnier, C.

Facilitator(s): Maura, J., Tanguy, V.