Faucet Snail Bithynia tentaculata
Help protect Wisconsin streams by preventing their spread!
- Invasive faucet snails were identified in Wisconsin in 2005 in the Mississippi River Watershed and have since spread to numerous locations around the state.
- Faucet snails have high growth rates allowing them to outcompete native mollusk populations.
- Faucet snails can act as parasite hosts, that when consumed, can kill native waterfowl.
- Faucet snails can live for up to a month in dry mud.
Identification: The faucet snail has a pale, brown shell with 5-6 slightly flattened whorls. The aperture is less than half the height of the shell. Adult faucet snails have a white tear-drop to oval-shaped operculum. The shell is usually 12-15mm tall (about 1/2”).
Ecology and Natural History: The faucet snail is native to Europe, ranging from Scandinavia to Greece. It is thought to have spread to the United States through solid ballast in timber ships going into Lake Michigan. It is found in freshwater but can inhabit intertidal zones. It eats algae and filter feeds.
Impacts of Introduction: Faucet snails rapid population rates and filter feeding have driven native snails and clams to be threatened. In its native habitats, faucet snails have been known to be hosts for parasites.