Barrier Removal and Water Quality Improvements: Future Implications for Controlling Sea Lamprey Populations in the Great Lakes Watershed

The U.S. Fish and Wildlife Service works in partnership with the Great Lakes Fishery Commission and Fisheries and Oceans Canada to implement the Sea Lamprey Control Program in the Great Lakes.  The Sea Lamprey (Petromyzon marinus) is an aquatic invasive species to the Great Lakes from the Atlantic Ocean.  Its parasitic life stage has severe impacts upon fish populations.  The primary control of sea lampreys is achieved by applying lampricides in infested streams to eliminate larval sea lampreys before they metamorphose and parasitize economically important fish.  Growing efforts to restore stream connectivity by the removal of dams/barriers to fish passage throughout the Great Lakes may lead to significant increases in sea lamprey spawning and larval habitat.  Since 2000, 238 requests for barrier removal/modification projects in U.S. waters of the Great Lakes have been reviewed for their effect on sea lamprey control efforts, and the number of reviews grows each year.  Removal of some barriers could provide new areas of infestation and result in additional lampricide treatments costing several hundred thousand dollars or more.  Also, many water quality improvement projects are in place throughout the Great Lakes Basin, potentially creating viable sea lamprey larval habitat where they once could not persist.