An analysis of species composition of the zooplankton, macrobenthos (two stations) and demersal fish from Northumberland (north-west North Sea) are reported. The four time-series show synchronous changes in species composition. While some of these changes coincide with changes in climateological variables, others do not. The degree of synchrony implies that either all the time-series are responding to a single set of extraneous forcing factors, or that food chain links, rapidly translate the signal through all ecosystem components.