Field guide
Identifying invasive species in Indiana lakes
These 10 plants and animals are not native to Indiana, and every one has been recorded in Indiana lakes — 57 of the lakes on this site have a record of at least one. Most can harm lakes, fish or shorelines. A few, such as the freshwater jellyfish, are harmless. Each card shows Indiana’s legal status and how many of our lakes have a record.
Plants and algae
Mussels, clams and snails
Crayfish and jellyfish
Fish
If you find it
- Don’t move it. Before leaving the water, remove all plants, mud and debris and drain all water from your boat, motor, live well, bilge and trailer. Carrying plants listed in Indiana’s Aquatic Plant Rule on vehicles, boats or trailers is illegal and can bring fines. Clean boater tips
- Never release bait or pets. Don’t dump bait, aquarium animals or water-garden plants into any lake or stream. Put unused bait in the trash.
- Report it. Take a photo, note where you saw it, and report it through EDDMapS or the GLEDN phone app, or contact Indiana DNR’s aquatic invasive species program at 317-234-3883 or ais@dnr.IN.gov. Experts there can confirm what you found.
- Ask before removing or treating. On public lakes, any control of aquatic plants — chemical, mechanical, physical or biological — needs an Indiana DNR aquatic vegetation control permit. 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: Midwest Glacial Lakes Partnership Conservation Planner; underlying records from the USGS Nonindigenous Aquatic Species database. Earliest dated records come from the same USGS database. Legal status follows Indiana’s invasive species rules, which are set out separately for plants, mussels and fish (Indiana DNR). Every lake page also lists the non-native species recorded there, including some not covered here, such as stocked sport fish.