Potential habitats and historical distribution changes of three species of musk deer in China under habitat fragmentation

Species potential habitat modeling and quality assessment are useful tools for effective conservation of endangered animals. Species distributions are influenced by environmental variables such as topography, climate, and anthropogenic disturbance. In recent years, global environmental changes have led to shrinking ranges for a variety of species. This study synthesizes records of the historical distribution of 3 musk deer species ( Moschus berezovskii , M. chrysogaster , and M. moschiferus ) from the 1970s to the 2010s, utilizing multiple data sources to reconstruct suitable distribution areas with BIOMOD2. We analyzed historical changes in distribution and used FRAGSTATS to explore the relationship between habitat fragmentation and the contraction of suitable habitats. The results show that suitable habitats for these species have decreased significantly over the past 50 yr (contraction rates: M. berezovskii 33.5%; M. moschiferus 48.9%; M. chrysogaster 59.1%). Among the environmental variables, climatic td (continentality) and dd<18 (degree-days below 18°C, heating degree-days) were the main factors responsible for the contraction of musk deer distribution. Results show significant differences in patch characteristics between contraction and non-contraction areas for M. berezovskii and M. moschiferus , suggesting that habitat fragmentation is another important cause of the reduced distribution. In order to better protect and manage the musk deer species, we recommend increasing connectivity between existing suitable habitats and enhancing the conservation of their potential habitats.