The Great Lakes region is trying to fight off aggressive non-native species, which pose a major threat to other wildlife, human health, waterways and the economy.
Invader Species Threaten Great Lakes Fishery
Silver carp, one of three invasive carp threatening the Great Lakes, jump out of the water due to boat motor vibrations. (T. Lawrence, Great Lakes Fishery Commission)
Asian carp are threatening to enter the Great Lakes basin through the Chicago and Sanitary Ship Canal - a man-made canal which links the two basins. (T. Lawrence, Great Lakes Fishery Commission)
Sea lampreys attach to fish with a suction cup mouth ringed with sharp teeth; they bore a hole through the fish and feed on the fish's blood and body fluids. (T. Lawrence, Great Lakes Fishery Commission)
Left uncontrolled, sea lampreys - seen here feeding on a trout - could cause the collapse of the Great Lakes fishery. (US Fish and Wildlife Service)
Sea lamprey mouths (Great Lakes Fishery Commission)
Lake trout with a scar from a sea lamprey. (Center for Great Lakes and Aquatic Sciences)
Zebra mussels cover a Lake Erie beach, causing property damage and disruptions to the food web. (Great Lakes Environmental Research Lab)
Zebra mussel colonies can clog intake pipes at water treatment plants, industrial facilities and power generation plants. (Don Schloesser, USGS, Biological Resources Division)