Field guide
Identifying invasive species in Minnesota lakes
These 4 plants and animals are not native to Minnesota, and every one has been recorded in Minnesota lakes — 596 of the lakes on this site have a record of at least one. Most can harm lakes, fish or shorelines. Each card shows Minnesota’s legal status and how many of our lakes have a record.
Plants and algae
Mussels, clams and snails
If you find it
- Don’t move it. Minnesota law requires you to clean aquatic plants and prohibited invasive species off boats, trailers and gear, and to drain all water and leave drain plugs out while transporting. Launching a boat or trailer with aquatic plants, zebra mussels or other prohibited invasive species attached is illegal, and docks, lifts and rafts must stay out of the water for 21 days before going into another body of water. What Minnesota law requires
- Never release bait or pets. Minnesota law forbids dumping bait in any lake or river: put unwanted bait in the trash. Never release bait, plants or aquarium pets into Minnesota waters.
- Report it. Note the exact location, take a photo, and contact the Minnesota DNR aquatic invasive species specialist for your region, or call the DNR at 888-646-6367. Experts there can confirm what you found.
- Ask before removing or treating. Aquatic plants in Minnesota public waters belong to the state. Applying herbicides always needs a DNR permit, and so does cutting or pulling submerged plants over more than 2,500 square feet. When a permit is needed
About this guide
These illustrations are AI-generated, not photographs, and are not to scale. They show what to look for; they are not a substitute for an expert identification.
A lake that is not listed may still have it. Records exist only where someone found the species and reported it, so “not recorded” does not mean “not present.”
Lake records: the Minnesota DNR List of Infested Waters (September 9, 2026). A lake counts here only where the DNR lists the species as confirmed in that water. Lakes listed only because they connect to an infested water are not counted. Earliest dated records come from the USGS Nonindigenous Aquatic Species database. Legal status follows Minnesota Rules chapter 6216, which sorts species into prohibited (6216.0250), regulated (6216.0260) and unregulated (6216.0270) lists (Minnesota DNR). Every lake page also shows the lake’s infested-waters listing, including species not covered here, and says when a lake is listed only because it connects to an infested water.