“…For some species, roach, bream, pike, white bream, ide and yellow eel, for some individuals seasonal migratory (cyclic repetitive detection) patterns were observed. This is comparable with another recent PIT-tag study in regional connectivity around the Noordzeekanaal region (North-West Netherlands), where partial migration was found in some species like bream, but no mass migrations alongside pumping station fishway barriers were observed (Griffioen et al 2022). Eel is the only diadromous species in our study and needs upstream connectivity from sea for the glass eel stages and downstream connectivity to sea for the silver eel stages.…”