Density distribution of the charismatic Kagu to guide conservation of endangered endemic rainforest species in New Caledonia

Le résumé fourni par la source

Abstract The Kagu ( Rhynochetos jubatus ) is an endangered endemic bird and emblem of New Caledonia, thus an ideal flagship species for conservation management and planning of protected areas on Grande Terre, the main island. We assessed the density distribution of Kagu by combining results of analyses at two spatial scales. At the local scale, we estimated density in two protected Kagu strongholds. At the island-wide scale, we modelled distribution using MaxEnt over the entire Kagu range on Grande Terre. We then combined these approaches to convert distribution probability into a density distribution. Proportion of rainforest and size of the largest rainforest patch within 250 m × 250 m raster cells were the main factors predicting Kagu distribution. Another important factor was distance to settlements, which is likely related to dog presence, the only significant predator of Kagu. The model identified nearly 2000 km 2 as habitat, which could potentially support over 27,000 Kagu. However, exluding the 5 km of sink habitat around settlements due to dog predation and applying a saturation of the population density at 23% ± 9%, which we observed in protected areas not managed for dogs, a realistic estimate of current Kagu numbers would be 3640 ± 1345. Only 12% of predicted Kagu habitat falls within protected areas, and only half of this protected area is under dog control. Moreover, only 30% of protected rainforest is situated on non-ultramafic soils, which are most suitable for Kagu and can support the highest densities. Numbers of Kagu and other endangered rainforest species could be significantly increased by establishing new protected areas combined with appropriate dog control. We recommend creating 250 km 2 of new protected areas in rainforest on non-ultramafic soils, which could potentially boost the Kagu population by 9000 individuals.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.