Seasonal Prey Abundance and Food Plasticity of the Vulnerable Snow Leopard (Panthera uncia) in the Lapchi Valley, Nepal Himalayas

SIMPLE SUMMARY: The snow leopard is an apex predator, residing in mountain ecosystems in Asia. This study was conducted in the Lapchi Valley of the Nepal Himalayas between November 2021 and March 2023 to investigate the seasonal variations in its prey availability and selectivity. Through camera traps and scat analysis, we identified the blue sheep, Himalayan musk deer, domestic horse, and sheep as key prey species for snow leopards. Snow leopards exhibited dietary diversity, consuming eleven prey species, with blue sheep as their primary wild prey and horses as preferred livestock. Seasonal variation in food preference was noted, where small mammals filled the nutritional requirements during winter’s prey scarcity. The study recommends genetic tools for further diet analysis and stresses the importance of transboundary research and population assessments in shaping effective conservation strategies. ABSTRACT: Conservation strategies for apex predators, like the snow leopard (Panthera uncia), depend on a robust understanding of their dietary preferences, prey abundance, and adaptability to changing ecological conditions. To address these critical conservation concerns, this study presents a comprehensive evidence on prey availability and preferences for snow leopards in the Lapchi Valley in the Nepal Himalayas from November 2021 to March 2023. Field data were collected through the installation of twenty-six camera traps at 16 strategically chosen locations, resulting in the recording of 1228 events of 19 mammalian species, including domesticated livestock. Simultaneously, the collection of twenty snow leopard scat samples over 3800 m above sea level allowed for a detailed dietary analysis. Photo capture rate index and biomass composition analysis were carried out and seasonal prey availability and consumption were statistically analyzed. A total of 16 potential prey species for the snow leopard were documented during the study period. Himalayan musk deer (Moschus leucogaster) was the most abundant prey species, but infrequent in the diet suggesting that are not the best bet prey for the snow leopards. Snow leopards were found to exhibit a diverse diet, consuming eleven prey species, with blue sheep (Pseudois nayaur) being their most consumed wild prey and horses as their preferred livestock. The Pianka’s index of dietary niche overlap between the summer and winter seasons were 0.576, suggesting a pronounced seasonal variation in food preference corroborating with the prey availability. The scarcity of larger preys in winter is compensated by small and meso-mammals in the diet, highlighting the snow leopard’s capacity for dietary plasticity in response to the variation in resource availability. This research suggests for the utilization of genetic tools to further explore snow leopard diet composition. Additionally, understanding transboundary movements and conducting population assessments will be imperative for the formulation of effective conservation strategies.