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 Scientists: Invaders are changing state lakes

Even before the sun comes up, hundreds of fishermen are expected to join in the Governor's Fishing Opener on Saturday.

But at some lakes across the state, there's an uneasy vigilance on the lookout for zebra mussels exploding in some lakes and causing havoc wherever they go.

The Minnesota Department of Natural Resources says they’re stepping-up efforts to prevent a potential lake-killer—zebra mussels can change the clarity and ecosystem of a lake, threatening the habitat of the fish.

The mussels are already in Prior Lake, upsetting fisherman like Richard Walbridge.

"It’s just going to turn around and ruin the whole lake. Going to start everything out and won't be able to reproduce fish and all the stuff will just be a dead lake," he said.

The state says they’re taking the threat very seriously, by increasing their enforcement budget by five times. Last year, $150,000 was designated to battle zebra mussels. Now it’s $750,000.

"There are zebra mussels on the lake. We’re just trying to make sure that people aren't transporting those invasive to other bodies of water," explained DNR Lt. Scott Carlson.

Nine enforcement officers, 80 inspectors, and 148 conservation officers will be at Minnesota lakes to prevent situations like the close call at Lake Minnetonka last week—when a boat, bought in Cincinnati, Ohio, covered with zebra muscles in the keel, was about to go into the waters.

Fortunately, DNR officials were able to catch the boat during an inspection.

If you're caught not washing your boat or bringing zebra mussels into a lake, it's a $500 fine.