Zebra mussels were first found in Wisconsin waters of Lake Michigan in 1990. They are now found in a number of inland Wisconsin waters including Marinette County's own Lake Noquebay. Zebra mussels are the only freshwater mollusks that can firmly attach themselves to solid objets. They will attach themselves to the shells of the native mussels in great masses, smothering them. Financial impacts have been significant to Wisconsin's water utilities and to power plants, where these animals congregate on and clog intake and distribution pipes. Once zebra mussels are established in a water body, very little can be done to control them. That is why it is very crucial to take precautions to prevent their introduction in the first place.