Writing about Zebra Mussels in Geneva Lake in winter when the lake is mostly covered with ice, may seem like the wrong time, but the preventative action starts before and not after the fact.
Geneva Lake is like a microcosm of Lake Michigan. Although Lake Michigan is four thousand times larger than Geneva Lake, there is a surprising environmental similarity between the two lakes. Both have become abnormally clear, but unfortunately, water this clear is not a good sign because it is mostly the result of the invasive Zebra Mussels filtering the lake water and making it clear. The mussels have decimated the phytoplankton, a single-celled green alga that is at the base of the food chain. The phytoplankton is eaten by the zooplankton, which is eaten by small fish, which in turn are eaten by the larger game fish. As the food supply diminishes at the bottom of the chain, so do the fish near the top of the chain. In addition, there is not enough plankton or nutrients clouding the water to enable the small prey fish to hide from predator fish.
Further complicating the problem is that the Zebra Mussels are polluting the lake bottom with their feces. As sunlight reaches greater depths, it converts nutrients from the mussels’ excrement into food for nuisance algae known as Cladophora, a very harmful algae not eaten by most native fish, and which can stink and be poisonous to birds if washed up on the shores. In many cases, the published reports of the two lakes mirror each other, and although there are differences in the fish species between the two lakes, the impact on the fish population in Geneva Lake may be following the decline in nearly all fish species seen in Lake Michigan.
The Geneva Shore Report supports the GLEA in its continued monitoring of the Geneva Lake, and its efforts to understand the interrelated impact of the various parameters affecting the lake so that methods can be developed and steps are taken, to minimize the adverse effects of the Zebra Mussels and other damaging environmental variables on the lake. Everything affects everything, and that includes the stocking of fish in Geneva Lake which can help minimize the Zebra Mussel situation or, conversely, make their impact even worse. The time for the DNR to think about adjusting the lake’s stocking, and its effect on the lake, is before they do it and not in hindsight because sometimes adding ‘more’ can net even ‘less,’ especially when there is a shortage in the food supply. The DNR needs to look at the overall environmental impact that their stocking has, and not just how it benefits the fishermen, as happened a few years ago when the DNR introduced Muskies (an invasive species) into Geneva Lake and created a mess. Muskies competed with and replaced other native species like the Northern Pike.