Abstract
Animal-trace data from the Third and the Fourth National Giant Panda Survey in the four reserves in the Shaanxi Qinling Mountains (Laoxiancheng, Foping, Changqing, and Huangbaiyuan) suggested that giant pandas unexpectedly have a lower occurrence rate in gentle locations. To explore the cause of this apparently counterintuitive preference, we used spatial and data analysis tools to analyze the spatial composition of the daily activity zones, the relative quantity of traces, the trace density, and the slope supply of the reserves. We found that the slope composition around gentle slopes and steep slopes is similar, with more traces clustered around gentle slopes. The area of the reserves with a 5°-15° slope is very small, and the density of traces is negatively correlated with the slope. So the slope distribution of giant panda traces is highly correlated with environmental supply. A reduced supply of suitable habitats leads to diminished availability, ultimately resulting in a narrower distribution range for giant pandas.In addition, combining the spatial supply situation, the use of trace density can more accurately reflect animal habitat selection preferences, which is more in line with the optimal foraging theory and animal habits. This study provides insights that should benefit future assessment and restoration of their habitats.