Hydrology and small pelagic fish drive the spatio–temporal dynamics of springtime zooplankton assemblages over the Bay of Biscay continental shelf

•Taxonomically and spatially–resolved zooplankton dataset over 16 years in spring.•Time–consistent zooplankton composition spatial structure with multi–table analysis.•Explanation of zooplankton spatial patterns with gradients in the pelagic ecosystem.•Zooplankton spatial pattern underpinned by taxonomic composition and size structure.•River plumes, temperature gradients and pelagic fish correlated zooplankton pattern.