SummaryThe paper reports the length-weight relationships of 55 species from the Three Gorges Reservoir (TGR) of the Yangtze River, China, and the largest reservoir in the world. A total of 24,176 specimens were collected from July 2012 to January 2015.Length-weight relationships for 33 fish species not recorded previously in FishBase, and the maximum total lengths computed for eight species are presented. The a values varied between 0.00054 and 0.01923, and the b values ranged from 2.729 to 3.583.The results will be useful for the application of sustainable management and conservation of these fishes in the TGR of the Yangtze River.

The construction of the Three Gorges Reservoir (TGR), the largest dam in the world, created novel spatial and seasonal fluctuations in food availability along the Yangtze River. We studied changes in diet and niche overlap of three co-occurring catfish species between the upper and lower sections of the TGR and across four hydrological seasons to investigate whether the diets of native catfish species reflect the fluctuations in food availability. Zoobenthos dominated the diets of the three species in the upper section, but shrimp made the bulk of the diet in the lower section. This was the case in every season except during the rising-water season when all three species increased the consumption of allochthonous foods. Diet breadth was significantly broader in the upper section relative to the lower section, and expanded during the rising-water season in the lower section. Niche overlap was significantly lower in the upper section than in the lower section. A non-significant trend of reduced niche overlap during the rising-water season was observed in both sections. Our results suggest that, in less than a decade, dietary plasticity facilitated the adaptation of these species to novel habitats and a shifted food-resource base formed by the impoundment.