Whether you are an avid angler or just an outdoor enthusiast who enjoys the Lower Chippewa River, fish contaminants and their sources affect you. Mercury is one of the contaminants found in fish. Mercury is a byproduct of coal combustion, which is the main source of power in the Midwest. Mercury from burning coal enters the atmosphere and then is rained into lakes and streams. Organisms at the bottom of the food chain, phytoplankton and zooplankton, are the primary consumers of mercury in our water. As each ascending consumer eats these tiny organisms, mercury is biomagnified up the food chain. Top predators such as walleye, Northern pike, and musky, have the highest bioaccumulated concentrations of mercury.
The Wisconsin Department of Natural Resources (WDNR) publishes fish consumption advisories to inform people about which fish species are not safe to eat. These guidelines can help you avoid potential health problems caused by eating locally caught fish. The WDNR advises pregnant women and children to consume fewer local fish because studies show that mercury can cause neurological problems in developing fetuses and young children. Together, we can all contribute by taking small steps to reduce the sources of mercury by decreasing our energy use and by encouraging cities and co-ops to switch to cleaner forms of energy such as wind, solar, nuclear, or hydroelectric power. One day, fish consumption advisories may not be needed. Now that's a vision we can all live with!