The invasive Chinese mystery snail (Cipangopaludina chinensis) was recently identified in the Heath, the shallow cove at the southern end of Thompson Lake, raising concern about its potential to spread further into the broader 4,400-acre lake.
The snails spend a good portion of their lives half buried in bottom sediments in quiet, shallow water, exactly the kind of habitat the Heath provides. The snail is native to Southeast Asia and was brought to North America as a food source and as popular aquarium species. It first appeared in San Francisco food markets in the late 1800s and by the 1960’s had spread to both coasts and into the Great Lakes. While eradication is not currently possible, some local communities have found success keeping populations in check through active removal. The Square Pond Improvement Association maintains a dedicated dive team that harvests snails from the lake bottom, and other lakes encourage shoreline owners to remove snails by hand when spotted. For more on Square Pond’s efforts, visit squarepond.org/pages/mystery-snails.asp.
The Thompson Lake Environmental Association is urging all boaters, paddlers, and anglers to practice Clean, Drain, Dry: cleaning watercraft of all aquatic plants and invasive species, draining all water by removing drain plugs, and drying equipment before placing it into another water body. Recreational boaters may transport this snail to new locations as it attaches to macrophytes which often infest boat hulls. The Chinese Mystery Snail can survive for long periods of air exposure, making transport between lakes on overland vectors such as trailered boats likely.
