Turning carp into a popular household and restaurant menu item is one way officials hope to rein in a decades-old invasion threatening native fish, mussels and aquatic plants in the Mississippi and other Midwestern rivers, as well as the Great Lakes. “The ‘carp’ name is so harsh that people won’t even try it,” said Kevin Irons, assistant fisheries chief with the Illinois Department of Natural Resources. “But it’s healthy, clean and it really tastes pretty darn good.”