Noninvasive genetic assessment of sloth bear diversity and population structure in Nepal
The genetic diversity of wildlife populations is crucial in maintaining their fitness and resilience to environmental changes and disease. Despite their rarity, ecological importance, and being an endangered species of public concern, information on sloth bears (Melursus ursinus) from Nepal is limited, and they are yet to receive conservation priority. To address this gap, we conducted Nepal's first noninvasive genetic surveys of sloth bear populations from 3 different habitat patches across their distribution range along the Churia-Terai landscape in Nepal between 2019 and 2021. Our study involved genotyping 127 samples using 12 microsatellite loci to determine the levels of genetic diversity and population genetic structure and using the control region of the mitochondrial genome for the haplotype analysis. We found 37 individuals in an area of approximately 1,000 km2 comprising forest and grassland habitats. Our results indicate that the sloth bears in Nepal are characterized by low genetic diversity (HE = 0.48) compared with other bear populations across its range. We had a limited number of individuals from different sampling areas, but their genotypes were consistent with there being no genetic structure between sampling areas. The study provides the crucial baseline information on the conservation genetics of sloth bears from Nepal and highlights the prospects for using noninvasive DNA sampling for research, monitoring, and conservation of bears.
