Feeding Behavior and Ecological Significance of Craspedacusta sowerbii in a Freshwater Reservoir: Insights from Prey Composition and Trophic Interactions.

Abstract

This study investigates the feeding behavior and ecological role of Craspedacusta sowerbii in the Danjiangkou Reservoir, a crucial freshwater source in central China. Through in situ cultivation, microscopic examination, and amplicon sequencing analysis, we identified the primary food sources of C. sowerbii within the reservoir's aquatic food web. Our results indicate that C. sowerbii predominantly consumes zooplankton, specifically rotifers, copepods, and cladocerans, while phytoplankton is ingested less frequently and often remains undigested. Amplicon sequencing data further confirms that the prey composition of C. sowerbii is enriched in zooplanktonic communities compared to phytoplanktonic communities. Our findings suggest that C. sowerbii plays a significant role in regulating plankton populations and shaping the planktonic community structure in the Danjiangkou Reservoir, thereby contributing to the ecosystem's functions and trophic dynamics. This study enhances our understanding of the feeding ecology of C. sowerbii and highlights its potential as a bioindicator species for assessing freshwater ecosystem health and monitoring water quality.