Chinese Mystery Snail
Invasive SpeciesFound in 493 lakes
Chinese Mystery Snail appears on state infested-waters lists for 493 surface waters. Boaters and anglers moving gear in or out of those lakes carry a clean-drain-dry obligation under state law. A 493-lake footprint means Chinese Mystery Snail 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.
The presence of Chinese Mystery Snail does not directly change a lake's LakeGrade rubric score — the grade measures the water itself, not the species inhabiting it. But invasive presence is a meaningful adjacent signal worth reading alongside the grade.
Lakes with Chinese Mystery Snail
| Lake | County | State | Grade | Depth |
|---|---|---|---|---|
| Big Bass Lake | Washburn | WI | A | 27 ft |
| Bass Lake | Washburn | WI | A | 31 ft |
| Bass Lake | Oconto | WI | A | 40 ft |
| Bass Lake | Oconto | WI | A | 25 ft |
| Clear Lake | Polk | WI | A | 26 ft |
| Clear Lake | Oneida | WI | A | 95 ft |
| Razorback Lake | Vilas | WI | A | 35 ft |
| Little Spider Lake | Vilas | WI | A | 23 ft |
| Long Lake | Burnett | WI | A | 41 ft |
| Pike Lake | Polk | WI | A | 33 ft |
| Wolf Lake | Adams | WI | A | 58 ft |
| Butternut Lake | Forest | WI | A | 42 ft |
| Green Lake | Oconto | WI | A | 25 ft |
| North Twin Lake | Polk | WI | A | 27 ft |
| Deer Lake | Polk | WI | A | 46 ft |
| Eagle Lake | Bayfield | WI | A | 52 ft |
| Big Lake | Vilas | WI | A | 30 ft |
| Upper Kaubashine Lake | Oneida | WI | A | 56 ft |
| Squash Lake | Oneida | WI | A | 74 ft |
| Shell Lake | Washburn | WI | A | 36 ft |
| Alva Lake | Oneida | WI | A | 43 ft |
| Franklin Lake | Forest | WI | A | 46 ft |
| Viola Lake | Burnett | WI | A | 34 ft |
| Big Portage Lake | Vilas | WI | A | 40 ft |
| Crystal Lake | Bayfield | WI | A | 29 ft |
| Perch Lake | Oneida | WI | A | 56 ft |
| Mildred Lake | Oneida | WI | A | 45 ft |
| Sea Lion Lake | Florence | WI | A | 82 ft |
| Upper Eau Claire Lake | Bayfield | WI | A | 92 ft |
| Half Moon Lake | Polk | WI | A | 60 ft |
| Paddock Lake | Kenosha | WI | A | 32 ft |
| Hasbrook Lake | Oneida | WI | A | 50 ft |
| Black Oak Lake | Vilas | WI | A | 85 ft |
| Spring Lake | Washburn | WI | A | 24 ft |
| Tozer Lake | Washburn | WI | A | 53 ft |
| Blue Lake | Oneida | WI | A | 49 ft |
| Shay Lake | Oconto | WI | A | 36 ft |
| Little Crawling Stone Lake | Vilas | WI | A | 44 ft |
| Dorothy Lake | Oneida | WI | A | 35 ft |
| Clearwater Lake | Oneida | WI | A | 48 ft |
| Big Bass Lake | Washburn | WI | A | 27 ft |
| Whitefish Lake | Douglas | WI | A | 102 ft |
| Long Interlaken Lake Deep | Vilas | WI | A | 65 ft |
| Gilas Lake | Marinette | WI | A | 88 ft |
| Bird Lake | Oneida | WI | A | 40 ft |
| Buffalo Lake | Oneida | WI | A | 27 ft |
| South Twin Lake | Polk | WI | A | 9 ft |
| Pine Ridge Lake | Oconto | WI | A | 30 ft |
| Bolger Lake | Oneida | WI | A | 45 ft |
| Halfmoon Lake | Oconto | WI | A | 38 ft |
Showing 50 of 493 infested lakes.
Frequently Asked Questions
How many lakes have chinese mystery snail?
Chinese Mystery Snail has been documented in 493 graded lakes: 493 in Wisconsin.
Does chinese mystery snail affect water quality?
Invasive species can significantly affect lake ecosystems. They may alter nutrient cycling, displace native species, and change water clarity. Lakes with chinese mystery snail should be monitored for changes in water quality over time.
Invasives Found With Chinese Mystery Snail
Co-occurs in 220 lakes · 432 total
Co-occurs in 197 lakes · 363 total
Co-occurs in 151 lakes · 244 total
Co-occurs in 146 lakes · 278 total
Co-occurs in 73 lakes · 688 total
Co-occurs in 25 lakes · 99 total
Source: EPA National Aquatic Resource Surveys, 2026.