Estuaries form a critical link between river systems and the oceans. These ecosystems often provide critical habitats for fishes, birds and even some shark and ray species. These productive and important areas are often some of the most threatened habitats, however, due to anthropogenic activities such as water extraction, pollution, illegal fishing, and encroachment.

Ecological monitoring is key to understanding estuarine functioning and change and, in 2014, SASC partnered with CapeNature, Department of Water Affairs and the Overstrand Municipality to undertake a long-term monitoring program in two major estuaries flowing in to Walker Bay.

Research Aims

This project aims to:

  • conduct long-term, inter-annual environmental surveys of two estuarine systems;
  • provide data to environmental management authorities regarding key ecological parameters;
  • provide reliable environmental trend data for estuarine management decisions;
  • conduct quarterly macro-invertebrate surveys to assess the feasibility of using macro-invertebrates as ecological indicators.

Research Techniques

Bi-monthly environmental sampling is conducted in the Klein and Bot Estuaries, for a total of four sampling days per month. Key environmental parameters such as salinity, turbidity, temperature, oxygen, and pH are collected using a YSI multi-parameter environmental sampling unit. Macro-invertebrate surveys are conducted using a sediment grab at 15 pre-determined sites along the length of the Klein River system.

This project is supported through the generous provision of sampling equipment by CapeNature and the Department of Water Affairs, as well as through donations from the Hermanus Lagoon Property Owners Association.