Six Midwest states , Canadian province of Ontario want action on Asian carp . Some environmentalists and lawmakers fear an economic and ecological disaster if the creatures breach man-made barriers . They ask the court to order states to shut down locks and dams and build a flood barrier . The large , voracious Asian fish is seen as a threat to native species . The fish got into the Mississippi River system from a fish farm during a flood in the 1990s .
Six Midwest states , Canadian province of Ontario want action on Asian carp . They ask the court to order states to shut down locks and dams and build a flood barrier . The large , voracious Asian fish is seen as a threat to native species . The fish got into the Mississippi River system from a fish farm during a flood in the 1990s .