Michigan Lake Depths

Field guide

Identifying invasive species in Michigan lakes

These 16 plants and animals are not native to Michigan, and every one has been recorded in Michigan lakes — 399 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 Michigan’s legal status and how many of our lakes have a record.

Plants and algae

Eurasian WatermilfoilMyriophyllum spicatumRestricted in Michigan122 lakesPurple LoosestrifeLythrum salicariaRestricted in Michigan104 lakesStarry StonewortNitellopsis obtusaProhibited in Michigan101 lakesCurly-leaf PondweedPotamogeton crispusRestricted in Michigan44 lakesCommon ReedPhragmites australis subsp. australisRestricted in Michigan26 lakesFlowering RushButomus umbellatusRestricted in Michigan23 lakes

Mussels, clams and snails

Zebra MusselDreissena polymorphaRestricted in Michigan206 lakesBanded MysterysnailViviparus georgianusNot on the state list32 lakesChinese MysterysnailCipangopaludina chinensisNot on the state list31 lakesFreshwater Golden ClamCorbicula flumineaNot on the state list30 lakes

Crayfish and jellyfish

Freshwater JellyfishCraspedacusta sowerbiiNot on the state list78 lakesRusty CrayfishFaxonius rusticusRestricted in Michigan10 lakes

Fish

Common CarpCyprinus carpioNot on the state list32 lakesRound GobyNeogobius melanostomusProhibited in Michigan10 lakesSea LampreyPetromyzon marinusGreat Lakes control program2 lakesGrass CarpCtenopharyngodon idellaProhibited in Michigan1 lake

If you find it

  • Don’t move it. Michigan law requires boaters to remove all aquatic plants from boats, equipment and trailers before launching. Before trailering, you must pull all drain plugs, drain live wells and bilges, and make sure the boat and trailer are free of aquatic plants and animals. What the law requires
  • Never release bait. Releasing baitfish into Michigan waters is illegal. Put unused bait in the trash, never in the water.
  • Report it. Take a photo, note where you saw it, and report it to the Midwest Invasive Species Information Network (MISIN) or through Michigan’s invasive species program. Experts there can confirm what you found.
  • Ask before removing or treating. Treating a lake with herbicides or other chemicals needs a state permit, and some removal work does too. Start with the state’s Aquatic Nuisance Control program before taking action.

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 Part 413 of Michigan’s Natural Resources and Environmental Protection Act (the state’s list). Every lake page also lists the non-native species recorded there, including some not covered here, such as stocked sport fish.