FILE - In this Jan. 12, 2010 file photo, Asian bighead carp swim in an exhibit at Chicago's Shedd Aquarium. A group of U.S. senators wants the federal government to move faster on preventing Asian carp from reaching the Great Lakes through waterways in the Chicago area. (AP Photo/M. Spencer Green, File)

FILE - In this Jan. 12, 2010 file photo, Asian bighead carp swim in an exhibit at Chicago's Shedd Aquarium. A group of U.S. senators wants the federal government to move faster on preventing Asian carp from reaching the Great Lakes through waterways in the Chicago area. (AP Photo/M. Spencer Green, File)