by Jennifer Dixon, Detroit Free Press
Crews from the U.S. Fish and Wildlife Service fanned out across the Detroit River on Saturday, scouring the water for the presence of sea lamprey larvae, which burrow into river bottoms until they become parasites that use their suction-cup mouths to prey on Great Lakes fish.
http://www.freep.com/story/news/local/michigan/2015/06/06/sea-lampreys-great-lakes-invasive/28620007/