Differences in the effect of copper sulfate on the mortality rate of Ostracod and Daphnia

Freshwater plankton habitats and its ecosystems are widely used indicators of chemical pollution. Control and estimation of effects induced by substances used in agriculture on freshwater organisms appear to be an important field of science, providing feedback on use of these chemicals. Our preliminary experiments with growing two species from different groups of freshwater crustaceans, Daphnia pulex and Ostracoda, in culture indicated different survival ability related to water quality, overcrowding, and food supply. We hypothesized that copper sulfate (CuSO₄), which is a long-established herbicide and pesticide used in pond cleaning, can also have a different mortality rate on these animals. To test this hypothesis, we established and utilized a simple reproducible method via treatment of controlled number of animals with different concentrations of CuSO₄. We performed a series of experiments with this chemical and our results indicated that it has different magnitudes of toxicity on two groups of freshwater crustaceans (Daphnia and Ostracoda). We conclude that this method can be helpful in ecological toxicity analysis and may be utilized for wider and more precise studies of different pesticides side effects.