Lake Superior's Isle Royale National Park is banning all organic fish bait like minnows or fish parts, in an attempt to stave off the fish disease VHS.
The park, off Minnesota's North Shore, will also require visiting boats to be disinfected before visiting park water. Disinfecting methods include drying a boat for five days or washing the boat in a bleach solution.
Park Superintendent Phyllis Green said the new rules will rely on cooperation from boaters and anglers.
"Not thinking about this puts what they care about very much at risk. And not taking the time to disinfect their gear before they move between water bodies, they could unknowingly carry something that we haven't had time to catch up with yet," Green said.
VHS has hit fish in all the Great Lakes except Lake Superior. It's known to affect dozens of fish species including popular game fish.