Sep 13, 2007 — This time of year, avid anglers flock to the St. Lawrence River in search of one of the most challenging freshwater catches: the muskellunge, or muskie. Some call it "the fish of 10,000 casts". This year's muskie season is clouded by bad news. A disease called VHS has killed hundreds of the fish. And each year seems to bring new invasive species to the river, causing change and uncertainty in the ecosystem. As researchers try to pin down the effects of these invaders, anglers are calling for action. David Sommerstein has part two in our series on invasive species.