The Yellow Sea Warm Current (YSWC) constitutes a significant hydrological feature in the Yellow Sea, particularly prominent during winter, facilitating the transport of warm, saline waters and warm-water species from the open sea to the Bohai and Yellow Seas. The YSWC induces alterations in the community structure and function of zooplankton. However, the effects of the YSWC on the functional trait compositions and functional groups of zooplankton remain unclear. This study aimed to elucidate the influence of the YSWC on the community structure, functional trait composition, and functional groups of zooplankton during the winter of 2016. The YSWC significantly impacted the zooplankton assemblage in the central Yellow Sea (CYSA), resulting in notable distinctions from the Shandong coastal assemblage (SCA) and Jiangsu coastal assemblage (JCA). Compared to the SCA and JCA (comprising 45 and 34 taxa, with abundances of 119.4 ± 114.6 ind·m^-3 and 82.8 ± 62.1 ind·m^-3, respectively), the CYSA exhibited higher species richness and abundance (with 51 taxa and 144.4 ± 103.4 ind·m^-3, respectively). This study documented 11 warm-water species, showing a decreasing trend in species richness and abundance from south to north. The CYSA was characterized by the predominance of medium-sized, current‒feeding, omnivorous‒herbivorous broadcast spawners, whereas the SCA and the JCA were predominantly dominated by giant-sized, ambush‒feeding carnivores. The Qingdao-Shidao anticyclonic eddy in the southern Shandong Province led to a significant increase in zooplankton abundance, potentially impacting Yellow Sea fishery resources. This research contributed to a deeper understanding of how YSWC influences the zooplankton community and offered fresh insights into the effects of YSWC on zooplankton function traits and functional groups.

zooplankton, community structure, functional group, Yellow Sea Warm Current