Daily Activity Rhythms of Animals in the Southwest Mountains, China: Influences of Interspecific Relationships and Seasons.

Simple Summary: Predation relationships and competition relationships shape interspecies coexistence in wild animal communities. Studying the temporal and spatial activity patterns of wild animals is crucial for understanding their behavior, species interactions, and resource requirements. We evaluated the spatiotemporal overlap between 15 different dominant species in the southwestern mountains of China, including Carnivora (such as Panthera pardus and Lynx lynx), Artiodactyla (such as Moschus spp. and Rusa unicolor), Primate (Macaca mulatta), and Galliformes (Crossoptilon crossoptilon, Ithaginis cruentus). We found that different species exhibit different activity patterns to reduce intense resource competition, with competition being more intense in cold seasons than warm seasons. This may be due to abundant resources in summer but scarce food in winter, as well as increased energy demands during cold seasons, as expected using physiology theory. Temporal and spatial factors regulate the interactions between apex predators, mesocarnivores, and herbivores. Prey adjust their activity patterns and spatial utilization based on predator activities; in turn, predators also adapt to the activities of their prey. To elucidate the factors influencing the daily activity rhythms of animals, 115 camera traps were established from September 2019 to June 2023 to assess the influences of interspecific relationships and seasons on the daily activity rhythms of animals in the southwest mountains of China. The species captured by the cameras included six Carnivora (such as Panthera pardus and Lynx lynx), six Artiodactyla (such as Moschus spp. and Rusa unicolor), one Primate (Macaca mulatta), and two Galliformes (Crossoptilon crossoptilon, Ithaginis cruentus). The results demonstrated that the 15 species exhibited different activity rhythms and peak activities to reduce intense resource competition. There were differences in the species' activity rhythms in different seasons, with competition among different species being more intense in the cold season than in the warm season. In predation relationships, the overlap coefficient in the cold season exceeded that of the warm season, possibly due to the abundant resources in summer and food scarcity in winter. In competitive relationships, 15 pairs of species exhibited significantly higher overlap coefficients in the cold season compared to the warm season, possibly due to increased demands for energy during the cold period or seasonal changes in predatory behavior. By analyzing the daily and seasonal activity patterns of dominant species in the study area, temporal niche overlaps were established to compare the competition levels between species. These findings indicate that the activity rhythms of the animals in this area not only result from evolutionary adaptation but are also influenced by season, food resources, and interspecific relationships (predation and competition). Thus, efforts should be made to reduce human interference, protect food resources in the winter, and monitor animals' interspecific relationships to protect animal diversity and maintain the stability of the ecosystem in this biodiversity hotspot in China. [ABSTRACT FROM AUTHOR]