[en] Thermal stresses caused by higher than ambient temperatures increased the susceptibility of fishes to disease and predation. Examples are given: Bluegill - Predator-prey relationships should be studied as a problem in community relationships. Experiments are reported to find the link between temperature and differential predation rates. In tropical conditions, there is no evidence of any damage to fish life due to warm water releases, however, experiments indicate that conditions in the waters receiving heated effluents are optimal to: proliferation of parasites and pathogens; oxygen supersaturation in outfall; weed growth