Seasonal variation in the mesozooplankton community structure and indicator species of the Yellow Sea

Abstract

We investigated the mesozooplankton community structure of the Yellow Sea in four seasons, one season for each year during 2019–2022. Total abundance and biomass were highest in autumn and spring, respectively. The mesozooplankton community was dominated by small copepods such as Acartia, Paracalanus, and Oithona species throughout all seasons. Euphausiid larvae were particularly abundant in spring, whereas tunicates appeared only in autumn. In spring, summer, and winter, mesozooplankton were clustered into groups from coastal waters to the open ocean. However, in autumn, the mesozooplankton community was divided by latitude and indicator species analysis suggested the influence of a warm current in this season. A comparison of our findings with those of previous studies indicated no clear change in zooplankton species composition or its seasonality in the Yellow Sea within the past 30 years.