Temporal change in estuarine fish communities

The interaction of fresh and marine waters in estuaries gives rise to highly dynamic systems which are characterised by large fluctuations in environmental conditions. Environmental conditions in estuaries change on an hourly, daily, weekly, monthly, annual and decadal basis, and as such a long-term time series of data on both the environment and the fish community is required to establish a sound understanding of temporal changes in fish communities within these systems. A number of studies on estuarine fish communities have been undertaken on scales from one year to up to 20 years to assess changes in the fish assemblage structure and to relate these changes to climate or environmental variability.