A toxic fish tale
While the causes and effects of fish kills have been studied repeatedly, the outcomes of poisoning that is less than lethal have not. Now, MSU researchers are entering uncharted waters as they conduct the first study on sublethal poisoning of Great Lakes fish.
Supported by a $498,334 grant from the Environmental Protection Agency (EPA), MSU will lead a team of researchers—which includes scientists from the University of Michigan and the University of Wisconsin–Milwaukee—to study how increasing doses of toxic substances affect yellow perch, a species of economic and ecological importance to the Great Lakes. The study will focus on exposure of the popular game fish to mercury, a neurotoxin present in most of the Great Lakes.
“Contaminants that don’t kill fish can still have many negative repercussions on fish populations, and we hope to shed some light on those issues,” says Cheryl Murphy, assistant professor of environmental toxicology.
Low doses of pollutants such as mercury can subtly disrupt key physiological processes related to behavior, growth, survival, and reproduction. Murphy’s team will test perch with continually increasing levels of toxins. As the levels of poison are increased, the scientists will examine their effects on hormone levels to their impact on overall populations of fish.The grant is part of the EPA’s Great Lakes Restoration Initiative, a $475 million plan that calls for aggressive efforts to address the cleanup of toxins, combat invasive species, promote near-shore health, and restore wetlands and other habitats.