From Great Lakes Wiki
These enormous snails can survive in murky and polluted water, and when seen can easily be identified as an alien species. These creatures are native to Burma, China, Japan, Korea and other South Asian areas where they were used as a food source. This species arrived in The Great Lakes when a man name Mr. Eugene Schemeck breeded a few in an aquariam and released them into the Niagra River in 1931. This species may cause water to become fowl because it apparently absorbs harmful components into it's flesh. Eating these animals is not advised!
