In this video, the Executive Director for Interlochen Public Radio (IPR), Peter Payette leads an informative discussion on the status and possible future of Lake Michigan’s fisheries – including salmon, lake trout, and other predator fish. We joined Payette at the Charlevoix Fisheries Research Station as he questioned two expert fish biologists with the Michigan Department of Natural Resources (DNR) about their efforts to understand the dynamics of Lake Michigan fisheries.
Jory Jonas has been working with the DNR for more than two decades, managing fish sampling projects and doing statistical analyses. She has collaborated with experts from other states and institutions to evaluate the status of many different fish populations, including the top predator fish such as Chinook salmon and Lake trout.
Ben Turschak is the newest fish biologist at the Charlevoix Fisheries Research Station where he works to assess the status of forage or prey fish, such as alewife, smelt, sculpin and round goby. Before joining the MDNR, he completed a graduate degree in Freshwater Sciences and Technology while working with Professor Harvey Bootsma at the University of Wisconsin – Milwaukee. His work helped explain the role quagga mussels have played in disrupting nutrient cycling in Lake Michigan. (For more on this topic, see: http://naturechange.org/2016/09/07/quaggas-lake-michigans-ecosystem-disruptors/)
In this engaging discussion, we learn that the DNR is continuing to support a desirable salmon fishery, even as the alewife population continues a general decline. Because predator fish such as Lake Trout, Brown Trout, and Burbot have learned to eat the invasive Round Goby, their populations are doing better. At the same time, some species of fish such as Cisco appear to be surging, without any specific help from fisheries managers.
One thing seems certain, a massive change in the ecology of Lake Michigan is on-going. Jory Jonas and Ben Turschak agree that the invasive quagga mussels now carpeting the floor of Lake Michigan have changed conditions at the bottom of the food chain. By filtering out plankton and removing nutrients, invasive mussels make it much more difficult for many species of forage or prey fish. In fact, there has been a general decline in the fish populations in Lake Michigan that correlates the overall increase in invasive zebra and quagga mussels. Where this is headed, Jonas says, we just don’t know.