Abstract
The nuclear power station, which ESCOM proposes to build on the coast near Cape Town, will be cooled by seawater and will cause the temperature of the water in the immediate vicinity of its outfall to be increased by about 6.degree. C. Experiments were conducted in an attempt to predict the biological effects of the increased temperature. Particular attention was paid to those organisms, e.g., kelp and mussels, which dominate the local kelp-bed ecosystem and to those such as the rock lobster which are of particular commercial importance. The effects of increased temperature on such parameters as growth rate, fecundity and spawning period were examined, and in many cases the higher temperature would be detrimental. Some of the possible overall effects on the entire kelp-bed ecosystem are discussed.