Microplastic pollution of threatened terrestrial wildlife in nature reserves of Qinling Mts., China

Waste pollution poses a significant threat to the survival of wildlife. In particular, microplastic pollution has received widespread attention. However, data on the exposure of threatened wildlife in nature conservation to microplastics, a very valuable basic data for animal conservation, are still limited. This study was conducted in the Qinling Mts., a key biodiversity hotspot and an essential genetic resource repository in China. Over the span from 2021 to 2023, a total of 22 fecal samples were collected from three species with different feeding habits over four months in two nature reserves in the Qinling Mts.: takin (Budorcas taxicolor), leopard cat (Prionailurus bengalensis), and golden snub-nosed monkey (Rhinopithecus roxellana). The potential reasons influencing the content of microplastics were studied on the basis of the distance of the fecal samples from the nearest residential area. Laser Direct Infrared Spectroscopy identified 34 types of microplastics, with diameters ranging from 20 to 100 mu m. Among them, acrylate copolymer, polyethylene, and polyurethane were the main types. Leopard cat (67.06 particles/g d.w.) had a significantly higher microplastic content than the takins (20.53 particles/g d.w.; Z=-3.162, P=0.002) and golden snub-nosed monkeys (27.69 particles/g d.w.; Z=-2.193, P=0.028). The average microplastic content in leopard cats and takins exhibited a negative correlation with the distance from residential areas. In conclusion, our study demonstrates the presence of microplastics within threatened terrestrial wildlife. Addressing this pressing issue may require concerted efforts to reduce plastic consumption in the surrounding regions, which could help mitigate the adverse impacts on wildlife.