Zebra Mussel Spread: How Many Lakes Are Affected?
Reviewed by LakeQuality Editorial Team · Updated
Zebra mussels are one of the most damaging invasive species in U.S. lakes. They filter massive volumes of water, altering nutrient cycles and starving native mussels and plankton. Here is what the data shows across the states we track.
By the Numbers
688
Zebra Mussel Lakes
859
Eurasian Milfoil Lakes
1,783
Any Invasive Species
33%
Lakes Affected
Most Affected Counties
| County | Zebra Mussel Lakes |
|---|---|
| Otter Tail County, MN | 62 |
| Crow Wing County, MN | 45 |
| Douglas County, MN | 43 |
| Cass County, MN | 37 |
| Becker County, MN | 32 |
| Waukesha County, WI | 30 |
| Wright County, MN | 21 |
| Beltrami County, MN | 21 |
| Walworth County, WI | 21 |
| Stearns County, MN | 20 |
| Itasca County, MN | 20 |
| St. Louis County, MN | 18 |
| Kandiyohi County, MN | 16 |
| Washington County, MN | 16 |
| Ramsey County, MN | 15 |
What Can You Do?
- Clean, remove all aquatic plants, animals, and mud from boats and equipment
- Drain, all water from livewells, bilge, and motors before leaving the launch
- Dry, allow boats to dry completely between lakes (Wisconsin requires 5 days or decontamination)
- Report, if you find zebra mussels on a lake not listed, report to your state DNR
View all invasive species data → · Full zebra mussel lake list →
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