Effects of Long-Term Exposures to Copper on Survival, Growth, and Reproduction of Brook Trout (Salvelinus fontinalis)

Abstract

During a 22-month period, all developmental stages of the brook trout (Salvelinus fontinalis) were exposed to copper (Cu(II)) concentrations ranging from 32.5 to 1.9 μg/liter. The highest concentration decreased survival and growth in adult fish and reduced both number of viable eggs produced and hatchability. Survival, growth, and reproductive success of adults in copper concentrations from 17.4 to 3.4 μg/liter did not differ from the control (1.9 μg/liter). Concentrations of 32.5 and 17.4 μg/liter had marked adverse effects on survival and growth of alevins and juvenile fish. Effects of copper on alevins–juveniles from unexposed parents apparently are no different than the effects on alevins–juveniles from parents exposed to copper. The maximum acceptable toxicant concentration (MATC) for brook trout exposed to copper in water with a hardness of 45 mg/liter (as CaCO₃) and a pH of 7.5 fell between 17.4 and 9.5 μg/liter copper. The mean 96-hr TL50 for 14-month-old brook trout exposed to copper was 100 μg/liter, and the application factor, MATC/96-hr TL50, lies between 0.17 and 0.10.