In the battle against aquatic invasive species (AIS), key weapons include research, inspections & early detection

Last month, the Minnesota Aquatic Invasive Species Research Center (MAISRC) announced nine new research projects scheduled to begin this summer. Included in the list are two projects aimed at controlling common carp – one to develop carp removal strategies that utilize social behaviors and one to explore a herpesvirus that could act as a potential biocontrol for the fish; a project to detect and map zebra mussel populations using multibeam sonar; an analysis of spiny waterflea invasions in the state; studies to examine the relationships between invasive species and native fish and vegetation; development and testing of new coatings to prevent zebra mussels from adhering; a genetic analysis to improve hybrid and Eurasian watermilfoil treatment efforts; and an evaluation of Eurasian water milfoil’s impacts on property values.

Eurasian watermilfoil, a non-native invasive species, has infested several lakes in Chisago, Ramsey and Washington Counties. It crowds out native aquatic plants and can make water recreation unpleasant.

Minnesota’s efforts to limit the spread of aquatic invasives (AIS) have been steadily accelerating over the past ten years. The MAISRC was founded in 2012 with funding from the Minnesota Environment and Natural Resources Trust Fund (proceeds from the MN State Lottery) and the Clean Water Fund (created by the 2008 Land and Water Legacy constitutional amendment). Since 2014, the Minnesota Legislature has also set aside $10 million per year to give to counties for AIS prevention efforts. In addition, the MN DNR operates a $2 million per year AIS program that coordinates statewide efforts, maintains a list of infested waters, establishes rules to prevent the spread of AIS, conducts watercraft inspections, and supports local education, prevention and control efforts.

In Washington County, AIS funding has been used to hire watercraft inspectors, conduct education activities, and implement an early detection program. Funding is also given to lake associations to manage existing AIS infestations.

Local residents learn how to ID common aquatic plants at a hands-on workshop
Local residents learn how to identify common native and invasive aquatic plants at a hands-on workshop led by Washington Conservation District and Comfort Lake – Forest Lake Watershed District.

Currently, 7% of the lakes is Minnesota are infested by at least one aquatic invasive species. The most common invasives locally include curlyleaf pondweed, common carp, Eurasian watermilfoil, and zebra mussels. Other invasive species found elsewhere in Minnesota but yet to be seen in Washington County include spiny waterflea and starry stonewort. These infestations can wreak havoc on aquatic ecosystems, as well as affecting water recreation and local business.

In the battle against AIS, research, watercraft inspections, and early detection programs have proven to be key weapons. Washington County currently uses approximately half of its $140,000 in annual AIS funding to conduct watercraft inspections at public launches to ensure that boaters are following state rules requiring them to clean watercrafts and trailers, drain water, and dispose of unused bait in the trash. So far this summer, Washington Conservation District’s watercraft inspectors have intercepted boats at Big Marine Lake, Lake Demontreville, Clear Lake (Forest Lake), and Square Lake that were attempting to launch with zebra mussels attached. Without a local inspections program in place, these incidents could have easily resulted in four new infestations.

Watercraft inspectors are stationed at public launches throughout Washington County and other parts of Minnesota to ensure that boaters don’t accidentally transport aquatic hitchhikers.

In addition to watercraft inspections, Washington County also uses a portion of its funds to conduct in-lake monitoring to identify and potentially treat new AIS infestations before they spread. This May, Washington Conservation District staff found six juvenile zebra mussels underneath a dock in Bone Lake (Scandia). Through the county’s rapid response program, the Washington Conservation District, Comfort Lake – Forest Lake Watershed District, and Minnesota DNR were able to work together to close the public launch and treat 0.57 acres surrounding the landing with EarthTec QZ, a copper-based pesticide used to kill zebra mussels. The project was the ninth such chemical treatment the Minnesota DNR has permitted since creating a zebra mussel pilot treatment program in 2011. Monitoring conducted next year will help to determine if the effort was successful.

Staff from Washington Conservation District and MN DNR work with contractors to install a containment boom at Bone Lake in Scandia, prior to applying an aquatic pesticide to kill zebra mussels.

The Minnesota Aquatic Invasive Species Research Center will showcase several of its latest research projects at an event to be held on Wednesday, September 18, 8am-5pm at the University of Minnesota, St. Paul campus (Continuing Education and Conference Center, 1890 Buford Ave.). The event will provide the public with an opportunity to tour the AIS lab, learn about new research, and talk with staff working at the center (Tickets are $40 at

Meanwhile, state and local partners agree on one thing – an ounce of prevention is worth a pound of cure. The single most important thing Minnesotans can do to protect the 93% of lakes, rivers and streams that are still AIS-free is to thoroughly clean, drain, and dry all boats, docks, lifts, trailers, jet skis, and hunting equipment before they go into the water. Do your part to help protect our Minnesota waters.


Learn more about AIS in Minnesota:

Learn more about the Minnesota AIS Research Center: