The Length–Weight Relationships of Eleven Fish Species From the Xinjiang River, China

As a vital tributary of the Poyang Lake system, the Xinjiang River plays a crucial role in maintaining regional aquatic biodiversity and sustainable fisheries. However, anthropogenic pressures and climate change have led to significant degradation in fish community structure, including declining species diversity and population miniaturization. This study presents the first systematic evaluation of length–weight relationships (LWRs) for 11 native fish species in Xinjiang River, filling an important gap in fundamental biological data for this region. Fish samples were collected from 10 sampling sites between June and September 2022. LWR parameters (W = aL^b) were determined using Le Cren’s log-transformation method, with 95% confidence intervals and coefficients of determination (R²) calculated. Results showed that the allometric coefficient (b) ranged from 2.24 to 3.28 among the 11 Cyprinidae species, with Hemiculter bleekeri and Toxabramis swinhonis exhibiting significant negative allometric growth (b < 3). All species demonstrated high model fit (R² > 0.95). This study reports the first LWR records for Megalobrama skolkovii and T. swinhonis in FishBase and reveals spatial variations in growth patterns compared with other Yangtze tributaries, likely reflecting ecological and anthropogenic influences. These findings provide essential data for evidence-based fisheries management and conservation strategies in the Xinjiang River basin.