Abstract:
The Yangtze finless porpoise (
Neophocaena asiaeorientalis), a flagship species for aquatic biodiversity conservation in the Yangtze River, serves as a key indicator of the river basin's ecological health. The Yangtze Xinluo Baiji National Nature Reserve is a crucial habitat for this species and one of the earliest established reserves for its protection. Monitoring the ecological conditions and population dynamics of the Yangtze finless porpoise within this reserve provides valuable insights into the broader environmental changes occurring in the mid-lower reaches of the Yangtze River. This study aims to explore the distribution characteristics of the Yangtze finless porpoise in the Xinluo section of the Yangtze River and the river morphological factors influencing its habitat selection, providing scientific basis for habitat restoration and protected area management. We analyzed survey data from 2006 to 2023, focusing on the distribution of the porpoises across different hydrological seasons and their correlation with environmental factors, utilizing habitat selection models. The results indicate that during the dry season, the porpoises are predominantly distributed in the Laowan, Panjiawan, and Paizhouwan areas. In contrast, during the wet season, their distribution is concentrated in Paizhouwan, showing significant seasonal variation. Above the Chibi Bridge, the porpoise population remains sparse across all surveys. Overall, the distribution of Yangtze finless porpoises is positively correlated with river channel curvature and floodplain area, suggesting that natural landscape features play a pivotal role in their distribution. According to the above results, we suggest that further studies on the physical and chemical characteristics of specific river channels in the protected waters to better understand the habitat selection mechanism of the Yangtze finless porpoises. Additionally, we recommend further strengthening the protection and restoration of floodplain habitats, maintaining the natural shoreline in high-density areas such as Laowan, Panjiawan, and Paizhouwan, and improving shoreline management practices. Furthermore, more intensive population monitoring is needed above the Chibi Bridge, along with habitat modification efforts to restore floodplains and improve connectivity between these critical habitats.