Metabarcoding diet analysis of snow leopards (panthera uncia) in Wolong National Nature Reserve, Sichuan Province

Abstract

As the apex predator of plateau ecosystems in Central Asia and the Qinghai-Tibet Plateau, the snow leopard (Panthera uncia) plays an essential role in maintaining food-web structure and ecosystem stability. Learning the diet composition and dynamics of the snow leopard is important for understanding its role in ecosystem functioning and interspecific interactions. Previous diet analyses of the snow leopard have been based mainly on morphological identification of food debris in the feces, though the accuracy of this practice has been broadly debated. The Qionglai Mountains are located at the southeast edge of the snow leopard range, harboring a small and relatively isolated population of snow leopards that are barely studied. Using non-invasive sampling, we collected 38 putative snow leopard fecal samples in the Wolong National Nature Reserve in the Qionglai Mountains. To identify the fecal origin, we extracted the fecal DNA and amplified the mitochondrial DNA 16S rRNA gene fragment. Twenty-two fecal samples were identified as originating from snow leopards. Subsequently, vertebrate universal primers and a snow leopard-specific blocking oligo were used to amplify the food components in the fecal DNA, and then high-throughput sequencing was performed to analyze the diet composition of snow leopards. The blue sheep (Pseudoisnayaur) was detected in 67% of the samples and was found to be the main staple food of snow leopards’ diet. The domestic yak (Bos grunniens) appeared in 33% of the fecal samples, also accounting for a high proportion of the snow leopard diet. In addition, pikas (Ochotona spp.) and birds were found in a small number of fecal samples. Therefore, wild prey was found to be the main food source for snow leopards in Wolong. However, livestock (yak) also accounted for a relatively large proportion of their diet.