Freshwater Fish Faces Uncertain Future

Fall is when avid anglers flock to the Great Lakes for one of the most challenging freshwater catches: the muskellunge,or muskie.

Some call it "the fish of 10-thousand casts."

This year's muskie season is clouded by bad news of a new fish disease and invasive species crowding muskie habitat.

David Sommerstein reports scientists on are watching this top-of-the-food-chain species carefully.