Sea Lamprey

For more than 30 years, the U.S. Fish and Wildlife Service has worked with Vermont and New York to control this invasive species and protect Lake Champlain. Fortunately, sea lamprey woundings are now at an all-time low.

The Great Lakes Fishery Commission today reported that populations of the invasive, parasitic sea lamprey remain at near-historic lows, below targets, in Lakes Michigan and Ontario, and above target, but holding steady, in Lakes Huron, Superior and Erie. Sea lamprey populations in Lake Huron are close to target levels and have been holding steady for the past five years. Abundances in Lakes Superior and Erie remain above target but have also decreased significantly since the near-record highs observed in 2017. Sea lampreys are the worst of the alien species to invade the Great Lakes. Before control, sea lampreys destroyed many times the human fish catch. Today, sea lamprey control is the foundation of the $7 billion Great Lakes fishery. The Commission and its partners are encouraged by the overall decrease in abundance of sea lampreys throughout the Great Lakes basin during 2019, but caution that environmental conditions, such as a prolonged spring and high precipitation events, contributed to the decrease.