Multi-scale habitat selection and constraints of a small Asian elephant population in Yunnan Nangunhe National Nature Reserve, China

The Asian elephant (Elephas maximus) populations in Yunnan Nangunhe National Nature Reserve (NNNR) represents the smallest known population in China and geographically isolated from other Asian elephant populations, potentially leading to their gradual extinction over time. Therefore, multi-scale habitat selection and habitat suitability analyses were conducted in this study to understand the key factors influencing the distribution of this population by employing camera-trap monitoring, unmanned aerial survey, and species distribution models. The results showed that elephant groups and solitary elephants exhibited strong selectivity for most habitat factors above 800 m, with elephant groups demonstrating higher vegetation requirements than solitary elephants. There are relatively few areas in NNNR where the habitat suitability for elephant groups and solitary elephants was good and high, primarily located in valley areas near rivers. The primary factors limiting their distribution were the presence of complex terrain and roads in large spaces surrounding the study area. Therefore, facilitating movement and genetic exchange between Asian elephants in this area and other populations by constructing corridors is challenging. Furthermore, based on the findings, it is advisable to adopt ex situ conservation to improve the population development of Asian elephants in NNNR. The insights gained from this research provide valuable guidance for the effective conservation and management of Asian elephants, contributing to their long-term survival and the preservation of biodiversity in the region.