Influence of river flow on the ecology of fishes in estuaries

Much is known about the biology and ecology of fishes in estuaries but detailed information on the factors influencing fish diversity and abundance is lacking. In an effort to provide some insight into the possible role of freshwater discharge in the diversity, abundance and energy flow pathways within estuarine fish assemblages, a series of studies were initiated in the Eastern Cape Province.

Between 2000 and 2008 this research theme was expanded to include the influence of major river pulses on fish assemblages in the Great Fish, Thukela and Kariega estuaries. A detailed study of the East Kleinemonde Estuary from 2006-2008 focused on the ecological effects of freshwater inputs on this system. In recent years Alan has been involved in a number of Resource Directed Measures (RDM) studies that have examined the freshwater requirements of the Keurbooms, Sout, Matjies and Sundays estuaries. In 2009 a RDM study is planned for the Msikaba Estuary.