Fishing, boating, scuba diving, and other recreational activities can spread aquatic nuisance species to new lakes, rivers, and streams. Nuisance species include zebra mussels, round gobies, spiny water fleas, whirling disease, rusty crayfish, Japanese shore crabs, sea lamprey, carp, ruffe, hydrilla, purple loosestrife, Asian clams, and other harmful aquatic plants or aquatic animals.