TURBIDITY GRADIENTS IN TWO INDO-PACIFIC ESTUARIES AND THEIR INFLUENCE ON FISH DISTRIBUTION

Abstract

Research undertaken in two widely separated estuaries in the Indo-Pacific, showed that both have distinct turbidity gradients. In the turbid St Lucia System, on the South East Coast of Africa (range 2 to 568 Nephelometric Turbidity Units (NTU)), different turbidity patterns were observed during summer and winter. The Embley Estuary, on the eastern side of the Gulf of Carpentaria, Queensland, Australia, although also turbid, had a much more restricted range (0.6 to 55.0 NTU), and showed three distinct seasonal patterns, referred to as the Wet, Early Dry and Late Dry.