Spatial Interspecific Association Patterns of Mammal Communities in the Selin Co National Nature Reserve, Tibet

To elucidate the mammalian community structure and interspecific relationships within the alpine ecosystem of the Qinghai–Tibet Plateau, this study was conducted in the Selin co National Nature Reserve for Black-necked Cranes, Tibet. Based on infrared camera monitoring data collected from June 2023 to July 2024, we analyzed mammalian species diversity and their spatial association patterns. A total of 150 infrared cameras were deployed, of which 128 were effectively retrieved, yielding 13,301 effective camera-trap days and 31,170 photographs of mammals. In total, 21 mammal species were recorded, belonging to 5 orders, 9 families, and 17 genera. The species accumulation curve approached an asymptote, indicating adequate sampling effort. Relative abundance analysis showed that Bharal (Pseudois nayaur) was the dominant species (RAI = 13.72), followed by Plateau Pika (Ochotona curzoniae) (RAI = 8.44), Moupin Pika (Ochotona thibetana) (RAI = 5.93), and Red Fox (Vulpes vulpes) (RAI = 5.50), while Snow Leopard (Panthera uncia) exhibited a moderate abundance level (RAI = 3.69). Significant differences in species diversity were observed among habitat types. Alpine meadow and meadow–desert ecotone exhibited higher diversity indices, whereas alpine desert and alpine bare rock habitats showed lower diversity. Interspecific association analysis identified 30 significant species pairs (p < 0.05), among which positive associations accounted for 93.3% and negative associations for 6.7%. The constructed association network comprised 16 nodes and 30 edges, with Chiru (Pantholops hodgsonii), Snow Leopard, and Red Fox serving as key hub species. Predator–prey pairs exhibited clear spatial coupling, while positive associations among herbivores mainly reflected shared utilization of similar habitat resources. The association structure varied across habitats, being most complex in alpine meadow, whereas no significant associations were detected in alpine desert. Overall, the mammalian community in this region is characterized by “low species richness and high endemism,” with interspecific relationships dominated by positive associations. Habitat heterogeneity plays a critical role in shaping the structure of the association network. These findings provide a scientific basis for biodiversity conservation and alpine ecosystem management on the Qinghai–Tibet Plateau.