Length and weight relationships of six freshwater fish species from the main channel of Yangtze River in China

Abstract

This present study first estimated the length and weight relationships of six freshwater endemic and endangered fish species collected from the main channel of the Yangtze River in China. The samples were captured quarterly from 13 different channel segments of the Yangtze River between October 2020 and August 2021. The total length and body weight were estimated for each sample. The a and b parameters of the length and weight relationships were calculated from log-transformed equation with 95 % confidence intervals. Correlation coefficients showed a high degree of positive correlation between the length and weight for five species, Pseudobagrus tenuifurcatus, Ancherythroculter nigrocauda, Chanodichthys oxycephalus, Culter oxycephaloides, and Saurogobio dumerili (r² > 0.91), and slightly lower positive correlation for an endemic species Acipenser dabryanus Duméril, 1869 (r² = 0.84 at p < 0.001). Our results have added new data on the length and weight relationships of the six freshwater species, and renewed the maximum length for the FishBase database.