I’ve spent the past two Fridays attending legislative public meetings in coastal communities on lakes Huron and Michigan to learn more about the threats posed by invasive species to the Great Lakes. The meetings resulted from a discussion with Rep. Holly Hughes of Muskegon earlier this year, in which she asked what Michigan State University Extension could do to help inform the public about the potential threats of silver carp and bighead carp if they were to become established in the Great Lakes. These and several other species, including grass carp and black carp, are commonly referred to as Asian carp species.
Silver carp, bighead carp and grass carp have established large populations in the Illinois River. This has dramatically altered the entire Illinois River ecosystem, devastating populations of once abundant native species that had been the basis of commercial and recreational fisheries. The silver carp pose a safety risk given their habit of leaping out of the water as boats pass by, occasionally striking boat occupants and causing injury. A constructed channel connects the headwaters of the Illinois River with the Chicago River and Calumet River, which drain into Lake Michigan. With those connections, there is a high likelihood that the Asian carp species may move into Lake Michigan, and if they become established in the Great Lakes, they could dramatically alter the dynamics of the lake ecosystems and perhaps disrupt the valuable fisheries we have in our lakes and rivers.
In the public meetings, Dan O’Keefe, Sea Grant Extension educator in Ottawa County, led off the presentations with a very thorough and up-to-date summary of the status and potential threats of these species if they become established in the Great Lakes. He was followed by Dave Clapp, fisheries research biologist with the Michigan Department of Natural Resources, who explained the plan that MDNR has developed to prevent and if necessary to respond to potential introduction of these invasive species to Michigan waters.
What is most striking from participating in all four of the sessions is that the most reliable solution we have is one that is very difficult to achieve: never allow the Asian carp species into the Great Lakes. Prevention is by far the most certain way of managing the risk these species pose, and prevention requires actions by everyone. After boating elsewhere, boaters need to be sure they clean and check their boats, trailers and other equipment before bringing them back into Michigan waters to be sure they aren’t bringing along aquatic hitchhikers. Managers of waters that may allow for fish to swim into the Great Lakes can install and operate preventive measures such as the use of physical barriers or electric weirs to prevent fish from entering the Great Lakes.
I was pleased to see the public respond to this challenge as they realized that there is no simple answer, no silver bullet, either to prevent the introduction of these species or to remove them if they become established. When your best solution is an informed public that is motivated to do the right thing, it will take a lot of meetings and other communication efforts to ensure that we benefit from best practices. Thanks to Dan and Dave for their willingness to spend a few Fridays informing concerned Michigan residents about these important matters.