Dataset for "Seasonal dynamics and stability of zooplankton community in Mytilus coruscus farming areas"

Large-scale mussel farming significantly affects marine plankton, yet the seasonal dynamics and stability of zooplankton community in mussel farms remain poorly understood. To elucidate the seasonal variation of zooplankton community and its response to changes of environmental factors and mussel feeding pressures, surveys on zooplankton community in mussel farms near Gouqi Island were carried out in October 2022 (autumn), May 2023 (spring), and August 2023 (summer). The results indicated that copepods were the dominant group across three seasons. The zooplankton community structure showed significant seasonal variation (PERMANOVA, p = 0.001), with WT and SAL identified as the primary environmental drivers by RDA analysis. Zooplankton abundance peaked in summer, driven by the dominance of small-sized copepod Paracalanus parvus, while autumn exhibited the highest species diversity. Meanwhile, ABC curves revealed distinct seasonal stability patterns: the zooplankton community was stable in spring (W > 0) but exhibited a disturbed status in summer and autumn (W < 0). This instability of zooplankton community and the dominance of small-sized copepods suggest a trend toward community miniaturization, likely driven by the dual pressures of intense top-down control (mussel feeding) and mesotrophic environmental conditions. The results demonstrate the combined effects of seasonal succession and aquaculture activities on zooplankton community structure, providing references for the monitoring of long-term variation of zooplankton community in mussel farms.