Abstract:

Aims: Mountain ungulates are crucial components of forest ecosystems, playing a significant role in sustaining biodiversity and ecological functions. However, understanding of ungulate population dynamics based on systematic long-term monitoring, and their long-term responses to human activities remain limited, especially in areas where large carnivores are absent. This study aims to investigate the interannual changes in site use and the environmental factors influencing the occupancy of common ungulates in a region historically lacking large carnivores. 

Methods: We conducted long-term monitoring by deploying 25 infrared camera grids in Guanba Village, Pingwu County, located in the southern Minshan of Southwest China (2019–2023). We focused on analyzing the interannual changes in site use and the factors affecting the occupancy rate for five common ungulate species: Chinese goral (Naemorhedus griseus), Reeves’s muntjac (Muntiacus reevesi), tufted deer (Elaphodus cephalophus), wild boar (Sus scrofa), and Takin (Budorcas tibetanus). 

Results: The findings revealed that four of the five monitored ungulate species (excluding wild boar) exhibited an increasing trend in both site use rate and relative abundance index. Notably, the occupancy rate of Takins increased from 0.04 in 2019 to 0.74 in 2023. Model averaging indicated that the impact of human activities varied across species: only Takins were significantly and positively influenced by distance to roads across several years (w = 0.919, 1.000, and 0.522 in respective years), consistently showing a preference for areas further from roads. The key environmental covariates affecting occupancy varied by species and year, suggesting that ungulates flexibly adjust their habitat use in response to shifting environmental resource pressures. 

Conclusions: This study provides a supplement to the population dynamics of ungulates in areas where large carnivores are absent and explores the patterns of environmental factors influencing ungulate occupancy rates. The results offer a scientific basis for the adaptive management of mountain ecosystems in Southwest China.

Key words: ungulates, occupancy model, southwest mountain, camera trap, population dynamic