Regional political leaders had been demanding the U.S. Army Corps of Engineers closed the navigation lock to keep the fish from the Great Lakes. They say its voracious appetite could devastate the fishing industry in the region. The Navigation lock is the last line of defense on Lake Michigan. Karp has been detected in Lake Calumet, about 6 km from Lake Michigan.
Commercial fishermen working in Illinois made the usual sample size in this area. The representative of the public says it is important to know where the fish as the fight continues to keep them out of the Great Lakes.