Non-native species that arrive in the Great Lakes via ballast waters are a substantial threat to the native fisheries in the lakes. At Isle Royale National Park, officials are implementing regulations with hopes they'll reduce the numbers of non-natives that infiltrate Lake Superior.

Beginning last week, park Superintendent Phyllis Green put into effect regulations that prohibit ballast discharges and exchanges by commercial and recreational boaters in waters extending four-and-a-half miles from the park's shores. The move is designed, right now, to combat the spread of viral hemorrhagic septicemia, a virus that causes internal bleeding in fish and which usually is fatal.

"It's a huge threat in all of the Great Lakes," Jay Glase, the Park Service's regional fisheries biologist, told the Mining Gazette. "It's already spread pretty widely in the Great Lakes since we first discovered it in 2005."

So far there have been no documented reports of the disease in Lake Superior, but Superintendent Green is concerned it could spread into the lake via the Soo Locks. As a result, boaters traveling Lake Superior are being urged to treat their ballast waters with chlorine in a mixture of 3 milligrams per liter of water. This mixture should kill the virus within two-and-a-half hours, after which ascorbic acid -- Vitamin C -- should be added to transform the chlorine into salt.

Of course, officials realize this is only a Band-Aid approach to dealing with the problem, especially for some of the large freighters that come through the locks. And Superintendent Green's regulations concern only vessels in the park's waters, which are a very small portion of Lake Superior.

Groups, including the National Parks Conservation Association, are working to see Congress pass legislation to clean up the Great Lakes. And earlier this summer the House of Representatives passed legislation that includes funding to help move that clean up along.

Whether the full Congress and President Bush go along with that plan remains to be seen.