Zebra Mussel
Invasive SpeciesFound in 688 lakes
Zebra mussels are the most consequential invasive in the upper Midwest lake system. They are small, fast-reproducing bivalves that filter enormous volumes of water, increase clarity in a misleading way (filtered water reads clearer on a Secchi disk), and disrupt the food web by stripping the planktonic base. A 688-lake footprint means Zebra Mussel prevention has shifted from "stop the spread" to "manage the new normal." Watercraft-inspection programs at boat launches and shoreline-management practices on individual lakes are doing most of the active prevention work.
On the LakeGrade rubric specifically: an A-grade lake with zebra mussels is partially "credited" for clarity that the mussels — not the underlying nutrient regime — produce. Reading both the grade and the invasive flag together gives a truer picture.
Lakes with Zebra Mussel
| Lake | County | State | Grade | Depth |
|---|---|---|---|---|
| North Long Lake | Crow Wing | MN | A | 97 ft |
| Long Lake | Becker | MN | A | 61 ft |
| Ossawinnamakee Lake | Crow Wing | MN | A | 63 ft |
| Clear Lake | Crow Wing | MN | A | 63 ft |
| Eagle Lake | Otter Tail | MN | A | 46 ft |
| Ida Lake | Douglas | MN | A | 106 ft |
| Star Lake | Otter Tail | MN | A | 94 ft |
| Upper Maple Lake | Wright | MN | A | 76 ft |
| Fish Lake | Otter Tail | MN | A | 69 ft |
| Woman Lake | Cass | MN | A | - |
| Girl Lake | Cass | MN | A | 81 ft |
| Bass Lake | Otter Tail | MN | A | - |
| Bass Lake | Crow Wing | MN | A | 47 ft |
| Cedar Lake | Morrison | MN | A | 88 ft |
| Pelican Lake | Otter Tail | MN | A | 55 ft |
| Big Pine Lake | Aitkin | MN | A | 78 ft |
| Alexander Lake | Morrison | MN | A | 64 ft |
| Gull Lake | Cass | MN | A | 80 ft |
| Lower Hay Lake | Crow Wing | MN | A | 100 ft |
| Latoka Lake | Douglas | MN | A | 108 ft |
| Pike Lake | St. Louis | MN | A | 60 ft |
| Trout Lake | Itasca | MN | A | 135 ft |
| Cowdry Lake | Douglas | MN | A | 52 ft |
| Andrusia Lake | Beltrami | MN | A | 60 ft |
| Big Mcdonald Lake | Otter Tail | MN | A | 46 ft |
| Island Lake | Crow Wing | MN | A | 76 ft |
| Lizzie Lake | Otter Tail | MN | A | 66 ft |
| Turtle Lake | Becker | MN | A | 73 ft |
| Pokegama Lake | Itasca | MN | A | 112 ft |
| Pickerel Lake | Becker | MN | A | 74 ft |
| George Lake | Kandiyohi | MN | A | 34 ft |
| Middle Cormorant Lake | Becker | MN | A | 40 ft |
| West Battle Lake | Otter Tail | MN | A | 108 ft |
| Kimball Lake | Crow Wing | MN | A | 77 ft |
| West Sylvia Lake | Wright | MN | A | 97 ft |
| Serpent Lake | Crow Wing | MN | A | 65 ft |
| Little Mcdonald Lake | Otter Tail | MN | A | 109 ft |
| Hand Lake | Cass | MN | A | 57 ft |
| Miltona Lake | Douglas | MN | A | 105 ft |
| Stuart Lake | Otter Tail | MN | A | 49 ft |
| Mina Lake | Douglas | MN | A | 123 ft |
| North Star Lake | Itasca | MN | A | 90 ft |
| Pulaski Lake | Wright | MN | A | - |
| Bay Lake | Crow Wing | MN | A | 74 ft |
| Big Trout Lake | Crow Wing | MN | A | 128 ft |
| Big Watab Lake | Stearns | MN | A | 123 ft |
| Rush Lake | Crow Wing | MN | A | 105 ft |
| Scalp Lake | Otter Tail | MN | A | 90 ft |
| Thunder Lake | Cass | MN | A | 95 ft |
| West Silent Lake | Otter Tail | MN | A | 58 ft |
Showing 50 of 688 infested lakes.
Frequently Asked Questions
How many lakes have zebra mussel?
Zebra Mussel has been documented in 688 graded lakes: 507 in Minnesota, 181 in Wisconsin.
Does zebra mussel affect water quality?
Invasive species can significantly affect lake ecosystems. They may alter nutrient cycling, displace native species, and change water clarity. Lakes with zebra mussel should be monitored for changes in water quality over time.
Invasives Found With Zebra Mussel
Co-occurs in 158 lakes · 859 total
Co-occurs in 142 lakes · 432 total
Co-occurs in 88 lakes · 363 total
Co-occurs in 81 lakes · 278 total
Co-occurs in 73 lakes · 493 total
Co-occurs in 49 lakes · 93 total
Source: EPA National Aquatic Resource Surveys, 2026.