Soon after she plunged into the water for her record swim across Lake Ontario last summer, Toronto’s Marilyn Bell felt a gnawing sensation at her middle. A sea lamprey, one of millions of the slimy, ...

Invasive sea lampreys prey on most species of large Great Lakes fish such as lake trout, brown trout, lake sturgeon, lake whitefish, ciscoes, burbot, walleye and catfish. These species are crucial to ...