Invasive sea lampreys in Great Lakes, and the lake trout they prey on, puzzle scientists

DETROIT — It’s a mystery. Invasive sea lamprey, the Great Lakes’ biggest predator, primarily feed on lake trout, one of the lakes’ most prized sports fish. When trout populations are high, researchers expect to see fewer lamprey-wounded fish, and more of those wounds when lamprey populations are spiking.But that’s not always what scientists are finding.New research into what may be behind the discrepancies holds promise to improve how sea lampreys are controlled in the Great Lakes, protecting a $7 billion fishery. It could allow lamprey managers to examine whether they have switched to other f...