Distribution and habitat suitability of the endangered lion-tailed macaque Macaca silenus and other primate species in the Kodagu region of the Western Ghats, India.

Abstract

Because of the universal decline in biodiversity, it is important to map and assess the populations of the endangered species, especially those endemic to small regions, in their remaining wild habitats. With the main focus on the distribution and habitat suitability of the endangered lion-tailed macaque, Macaca silenus, we carried out a survey on primates in the Kodagu region of the Western Ghats, an area not properly explored earlier. The survey trails covered a length of 523 km. We encountered 185 groups of primates including 112, 12, 43 and 18 groups of bonnet macaques, M. radiata, lion-tailed macaques, black-footed gray langurs, Semnopithecus hypoleucos and Nilgiri langurs, S. johnii, respectively. The Brahmagiri Hills harbored the northernmost group of Nilgiri langurs and the southernmost group of black-footed gray langurs. Habitat suitability analysis revealed that the distribution of bonnet macaques and black-footed gray langurs was associated with a large number of environmental factors whereas only a few factors each influenced the distribution of other primate species. When considering the whole landscape spanning over 1295 km², black-footed gray langurs (961 km²), bonnet macaques (910 km²) and lion-tailed macaques (779 km²) had more suitable habitats than Nilgiri langurs (258 km²). The reserved forests between two Wildlife Sanctuaries covered an area of 311 km² where 282 km², 228 km², 272 km², and 140 km² areas were found to be suitable for lion-tailed macaques, bonnet macaques, black-footed gray langurs and Nilgiri langurs, respectively. We recommend these reserved forests to be included in the protected area network. The study brings out the Kodagu region to be a potential conservation area not only for the lion-tailed macaques but also for other primate species.