Wisconsin’s beautiful lakes are under threat from Aquatic Invasive Species (AIS) that harm native ecosystems, degrade water quality, and interfere with recreation like boating and fishing. These non-native plants and animals can spread rapidly, often by human activity, making awareness and proactive management critical to preserving our cherished waters.
A prime example is the Curly-leaf Pondweed (CLP), a non-native plant discovered in 2024 in several areas of Lake Shishebogama, which poses a threat to our lake’s aquatic health.
The most effective tool is stopping new invasions before they start. State law requires all boaters to take specific actions before leaving and before entering a waterbody. SGLA secures a grant each year from DNR to help support the Clean Boats, Clean Waters inspection program at the Gunlock Lake public launch. On summer weekends we have a paid launch monitor; we rely on volunteers to help inspect boats during the summer weekdays.
Carefully inspect your boat, trailer, and all equipment (including fishing nets and decoys). Remove all attached aquatic plants and animals.
Drain all water from your boat and equipment, including the bilge, ballast tank, bait bucket, and live well.
If possible, clean your boat and equipment with high-pressure hot water, or allow it to dry completely for at least five days before launching into a different lake.
Check back in early summer 2026 to see the SignUp schedule for volunteering at the launch.
Organized shoreline sweeps and other manual control efforts are essential for early detection and removal of small infestations. Consider volunteering for the shoreline sweeps teams where we scout for AIS such as purple loosestrife, wild iris and narrow leaf cattail (see fact sheets below) and report sitings to the SGLA board. We also organize volunteer teams to remove loosestrife (in particular) to help control its future growth and spread. Please visit our Volunteer page and let us know if you will help!
Click here to see a description of purple loosestrife and how to remove it properly.
Click here to for a factsheet on identifying and removing wild iris.
While narrow leaf cattail does not require removal, we still keep an eye on it. See this factsheet.
CLP was detected in Lake Shish in the summer of 2024, in Rockwood Bay. SGLA is working with the DNR and the LDF Tribe on several approaches to mitigate and hopefully control the spread of CLP. Click here to see a map of the CLP infested areas. Please avoid boating in these areas if possible; check your props and other equipment and remove any weeds before your leave the area to avoid transporting any CLP plants to other areas of our lakes.
Curly Leaf Pondweed is different from other AIS in that it grows under the ice in the winter, and reproduces with seed-like “pinecones” called turions which form in May or June, then drop to the lakebed. This makes it challenging to remove the CLP plants before they go to “seed” because the water is so cold, and requires special gear and training for anyone attempting to remove the plants.
SGLA is working to obtain a DNR Early Detection Grant to help us mitigate CLP using diver assisted suction (DASH) in early spring 2026 when the CLP is growing but before turions form. We will also have signs in the areas on Shish where CLP has been detected, warning boaters to avoid the area and clean equipment before leaving the area if they must enter it. Herbicide use is not an option and we cannot obtain a permit due to herbicide use being prohibited in tribal waters. That being said, DNR has advised that herbicides are not particularly effective in treating CLP and can also harm native pondweed, thus making the waters even more susceptible to AIS infestation due to lack of plant competition.
