The pattern of occurrence of medusae off the north-east coast of England are described for the period 1990–1996. The predatory role of the medusae, Aglantha digitale, was examined by comparison of estimated predation rates with those of other planktonic predators. Aglanthe digitale was found to have the potential to considerably reduce copepod abundances, particularly in winter. Other important predators were the amphipod Themisto compressa and the chaetognath Sagitta elegans. There was a great deal of seasonal and interannual variability in predatory impact, with predators such as Pleurobrachia pileus and Meganyctiphanes norvegica occasionally exerting a high predatory impact. Previous studies have identified an important community structuring role for predation in winter in this area, this study shows that planktonic predators can influence copepod abundances throughout the year.