Faucet Snails (Bithynia tentaculata)
Faucet snails (Bithynia tentaculata) are small invaders that threaten waterfowl, food webs, and may clog water intakes. They host three intestinal flukes that can kill scaup, coots, and other waterfowl that consume them. Native to Europe, they were first found in the Great Lakes in the 1870s, likely spread with solid ballast used in large timber transport ships or by contaminated vegetation used in packing crates. Faucet snails quickly spread to inland waters, often reaching high densities and outcompeting native snails.
Faucet snails are found in the Great Lakes, in some inland waters in provinces and states bordering the Great Lakes, in Lake Champlain south to Washington, D.C., in some lakes in Montana, and in the Mississippi River near La Crosse, WI. They can spread by attaching to aquatic plants, boats, anchors, decoy anchors, and other recreational equipment. Faucet snails can close their shells allowing them to survive out of water for days. Eradicating infestations is nearly impossible. Your actions and your help in reporting new infestations are vital for preventing their spread.
Identify Faucet Snails
- Up to 1/2" (1. 3 cm) long
- Found on rocky shorelines, river and lake bottoms, aquatic vegetation, and docks
- Difficult to distinguish from native snails or immature invasive mystery snails
What You Can Do
- Learn to recognize faucet snails.
Follow Minnesota Aquatic Invasive Species Laws:
- Clean all aquatic plants, animals and mud from watercraft, trailers, docks, lifts, anchors and other recreational equipment before leaving access.
- Drain water-related equipment (boat, ballast tanks, portable bait containers, motor) and drain bilge, livewell and baitwell by removing drain plugs before leaving water access. Keep drain plugs out while transporting watercraft.
- Dispose of unwanted bait, worms and fish parts in the trash.
- Scrub soles of footwear with stiff-bristled brush.
- Spray watercraft and equipment with high-pressure water, or
- Rinse with very hot water, or
- Dry for at least 5 days.
Report New Sightings — note exact location; place specimens in a sealed plastic bag or store in rubbing (isopropyl) alcohol; and call a Minnesota DNR Invasive Species Specialist (see www.mndnr.gov/invasives/contacts.html), 1-888-MINNDNR or (651) 259-5100; or the Minnesota Sea Grant Program in Duluth, (218) 726-8712.
Know the Rules!
Specimens are needed to confirm sightings, but some jurisdictions prohibit possession and transport of invasive aquatic plants and animals. Contact your local natural resource management agency for instructions. Unauthorized introduction of plants, fish, or invertebrates into the wild is illegal. Protect your property and our waters.