What Are Aquatic Invasive Species?

Photo Credit: Paul Skawinski

Aquatic invasive species (AIS) are non-native plants and animals that can have a negative impact on our waters. You have probably heard of some of them: zebra and quagga mussels, Eurasian watermilfoil, curly-leaf pondweed, New Zealand mudsnails, phragmites, purple loosestrife, and many more.

Because they do not have predators in Wisconsin and can thrive in a wide range of places, AIS can often overpopulate or “take over” our waterbodies. They can also spread easily from place to place on boats, waders, or other gear.

Raking invasive species
Photo Credit: Barb Schmidt

AIS can negatively impact our waters in several ways. They can compete with native plants and animals and harm game fish populations. They can reduce opportunities for recreation, fouling boat engines and equipment and making waters unpleasant to swim in. They can also have a negative impact on local economies by impacting recreation, tourism, and property values.

In recent years, many new AIS have been found in the Rock River Basin, including New Zealand mudsnails, zebra mussels, and spiny water fleas. We are working to prevent new AIS from entering the watershed, and to reduce the impact and spread of the AIS that are already here.


Our Aquatic Invasive Species Projects

Our Aquatic Invasive Species Program aims to prevent the spread of aquatic invasive species (AIS) in the Rock River Basin by educating community members about AIS and empowering them to take action.  Our AIS program is currently focused on Dodge County and Rock County, WI.

Our projects:

Fill out a volunteer interest form or visit the upcoming AIS event calendar if you are interested in volunteering with any of these projects. No experience is required – we will teach you what you need to know!

You can also contact our AIS coordinator Lizzy for more information.

Purple Loosestrife Biocontrol

Photo Credit: Thomas Boisvert
Photo Credit: Addie Schlussel

We raise and release beetles that feed on purple loosestrife, giving native wetland plants a leg up in their competition against this widespread invasive plant. Our purple loosestrife biocontrol project is a collaboration with WDNR, Lake Koshkonong Wetlands Association, Jefferson County Land and Water Conservation Department, Lake Ripley Management District, and Neighborhood House.

Volunteer opportunities are available! Learn more about purple loosestrife biocontrol.

Citizen Lake Monitoring Network (CLMN)

Volunteers in a boat on a body of water raking weeds out of the water
Photo Credit: Chris Hamerla

We train and support volunteer lake monitors, who measure water clarity and search for new populations of invasive species. CLMN is a partnership between WDNR, University of Wisconsin Stevens Point Extension Lakes, and local organizations. Learn more about CLMN.

Snapshot Day

Two people hiking in a creek holding a list of photos and descriptions of invasive species
Photo Credit: AJ Leiden

This one-day, statewide volunteer event aims to teach community members about invasive species and take a “snapshot” of new and existing AIS populations. Think of it as an invasive species scavenger hunt!

Learn more about Snapshot Day through this StoryMap produced by River Alliance of Wisconsin.

Two people in separate kayaks on a body of water
Photo Credit: Chris Hamerla

Project RED (Riverine Early Detection)

We train volunteers how to search for invasive species while paddling or wading their favorite streams or rivers. Learn more about Project RED.

Bait Shop Initiative

We provide bait shops with educational materials so they can help their customers learn how to prevent the spread of invasive species.



A volunteer speaking with two men in a fishing boat
Photo Credit: Jeanne Scherer

Clean Boats Clean Waters

We offer support to lake groups who wish to staff boat landings with Clean Boats Clean Waters inspectors, who educate boaters about how to prevent the spread of invasive species.

Learn more about Clean Boats Clean Waters from WDNR and University of Wisconsin Stevens Point Extension Lakes.

Support to Other Watershed Groups

We provide organizations in Dodge and Rock Counties with support on AIS-related issues and projects. We can respond to reports of new AIS or other AIS issues, answer questions, and assist with grant applications. We are always happy to form new partnerships! Contact AIS coordinator Lizzy to discuss any potential partnerships.

Clean your gear after boating, fishing, or otherwise enjoying our waters.

A sign next to a body of water with a dock that says "Prevent the Spread of Invasive Species: It's the Law!"This is the most important step you can take to prevent the spread of invasive species! AIS can “hitchhike” on our boats or gear from one waterbody to another, but cleaning your equipment can reduce this risk.

Step 1: Inspect your boat, trailer, waders, or other equipment.

Step 2: Remove all attached plants, animals, and mud.

Step 3: Drain all water from boats, vehicles, and equipment.

Step 4: Never move live plants or animals away from a waterbody.

Click here for more information about how you can follow these steps, whether you are a fisher, boater, or other water enthusiast.

Consider decontaminating your gear.

A woman decontaminates her boat as it's hooked up to a truck
Photo Credit: Bob Korth

After cleaning your equipment, you can also take the additional step of disinfection to kill any microscopic seeds or larvae that may remind behind. Some options for this step are:

  • Steam cleaning
  • Soaking in hot water (at least 140°F) for 10 minutes
  • Drying for at least five days
  • Soaking in a dilute bleach solution
  • Spraying with Virkon® Aquatic

Not all disinfection methods work against all AIS.  For example, New Zealand mudsnails are not killed by bleach or drying.  It is helpful to know which AIS are present on the waterbody you’ve been using, and pick a method that will be effective against them.

Click here for more information on disinfection methods, how to find out which AIS are on your waterbody, and how to choose a disinfection method.

A pamphlet titled "Fishing with Bait"
Photo Credit: Chris Hamerla

Follow local bait regulations.

If you have added lake or river water to your live bait container, you should use that bait only on the same waterbody, or you should discard it. Bringing the bait to a different waterbody could spread fish diseases, like Viral Hemorrhagic Septicemia (VHS).

Click here for more information on fishing with live bait.

A dime covered with tiny shells
Photo Credit: Chris Hamerla

Learn how to recognize invasive species.

Once you know how to recognize invasive species, you will begin to see them everywhere! You will also be able to tell if you’ve found an invasive species that is new to the area.

The Wisconsin AIS Early Detector Handbook from the Wisconsin Department of Natural Resources will get you started on learning how to recognize invasive species. Download the Handbook (free online), or purchase a physical copy, here. Training workshops on identifying AIS may also be available – contact us for more information.

Report if you find a new invasive species.

A woman in a boat on a body of water holds up seaweed she's collected with a rake
Photo Credit: Chris Hamerla

Every year, community members are responsible for hundreds of reports of new AIS statewide. If you find an AIS that is new to a waterbody, you can help by reporting it.

Once WDNR and others know about your find, they can launch a response to it. This response could include searching for it in nearby waterbodies, educating people about how to prevent the spread of the AIS, or, if feasible, attempting to control or eradicate the AIS.

You can find out which AIS are known to be on which waterbodies here. If you have found a new AIS, you can contact us or your regional AIS coordinator.

An adult and two children with a net sitting on a doc looking into the water
Photo Credit: Gail Nicoll

Volunteer with an AIS project.

Rock River Coalition has volunteer opportunities with several AIS projects. No experience is necessary, and you can participate from land or with your feet wet. Fill out a volunteer interest form or check out our aquatic invasive species volunteers page for more information.