Influence of Mild Hypercapnia on the Effects of Environmental Acidification on Rainbow Trout (Salmo Gairdneri)

Abstract

The physiological consequences of lethal ambient acid levels in adult fish have been previously investigated (Lloyd & Jordan, 1964; Packer & Dunson, 1972; Lievestad & Muniz, 1976). Acidaemia associated with a loss of total carbonate and/ or electrolyte loss have been implicated as the cause of death but the sublethal physiological effects leading to one or both of these conditions have not been fully clarified. Neville (1979) has shown that the acidaemia of trout exposed to pH 4 under normocapnic conditions for 5 days is not due to build-up of lactic acid.