Aquatic Invasive Species

Aquatic Invasive Species (AIS) are in the news often and typically have a more significant impact on native plants and animals and their habitats in larger rivers like the St. Louis River and its estuary, and on lakes and wetlands, than on smaller tributary streams. Adverse impacts to native communities occur from direct competition for food and habitat, predation, and disease and also indirectly by altering food chains and webs- which can dramatically affect water quality.

This issue can be confusing because of the many terms used to describe the “problem” species and the sensationalism used by some media outlets when describing the newest Great Lakes Basin troublemaker.

Nevertheless, the introduction and spread of harmful exotic species continues to cause significant food web problems and indirectly water quality problems in Minnesota and throughout the Great Lakes Basin.

MN DNR

The Minnesota DNR describes Invasive Species as:

Species that have been introduced, or moved, by human activities to a location where they do not naturally occur are termed "exotic," "nonnative," "alien," and "nonindigenous." Nonnative species are not necessarily harmful, in fact the majority have beneficial purposes. When nonnative species cause ecological or economic problems, they are termed "invasive" or "harmful exotic species." Minnesota's natural resources are threatened by invasive species such as the zebra mussel, Eurasian watermilfoil, purple loosestrife, gypsy moth, and garlic mustard. These species, along with new invasive species, could be easily spread within the state if citizens, businesses, and visitors don't take necessary steps to contain them.

Aquatic Animals     Aquatic Plants


Other sources of information:

LS Binational ForumLake Superior Binational Forum

Links to agencies and organizations that developed extensive resources to prevent the spread of invasive species in the Lake Superior basin.

MN Sea GrantMinnesota Sea Grant

Up-to-date Fact sheets, articles, photographs and identification schematics

GLIFWCGreat Lakes Indian Fish & Wildlife Commission

Exotic Plant Information Center

St Louis County: Aquatic Invasive Species Risk Assessment Tool

Screenshot of the story map new The St. Louis County, MN Aquatic Invasive Species Risk Assessment Tool conveys the risk which lakes have in receiving new aquatic invasive species. We input spatial, environmental, and lakeshore development data into models to assess the risk of 1,139 lakes larger than 5 acres and assigned a unique basin identification number (i.e. these lakes exist in the MNDNR LakeFinder search tool). Additional information such as boater movement and lake habitat are provided to infer what AIS may pose the greatest risk of becoming established.

Worm WatchGreat Lakes Worm Watch

Surprisingly, earthworms are not native to our region. Although not aquatic, they are being spread by fishermen who don’t know that they are having an adverse impact on Northwoods forest soils and trees.

MPCA Minnesota’s Vessel Discharge
(Ballast Water) Program

Minnesota was the first state to directly address this issue.

WI DNRWisconsin DNR

…preventing the introduction of new invasive species…, preventing the spread of invasives …already in the state, and controlling established populations when possible


Can you identify the invader from this list?

Eurasian Watermilfoil, zebra mussels, Purple Loosestrife, lamprey, Charcarodon megalodon, Eurasian ruffe, Tahoe Tessie, Audrey II, Davy Jones, spiny water fleas, Amazon lagoon creature, earthworm, curly leaf pondweed

Invasives?