The Great Lakes are a valuable resource shared by Canada and the United States. Over 40 million people depend on the Great Lakes to provide food, drinking water and recreation. The health of the Great Lakes fishery is under constant threat from habitat loss, pollution and invasive species including sea lampreys. Through stewardship and cooperation, we are tackling some of our biggest challenges. Sea lamprey control is one area where we have achieved substantial success.
Sea lampreys are primitive fish native to the Atlantic Ocean.
In the Great Lakes they have no commercial value and fish do not normally feed on them. Lacking jaws, their round mouths form a sucking disc filled with sharp, horn-shaped teeth that surround a rasping tongue. Unlike most fish, a lamprey's body has cartilage but no bones, scaleless skin, no paired fins, no lateral line, and no swim bladder. Sea lampreys entered the Great Lakes from the Atlantic Ocean through man-made shipping canals and were first observed in Lake Ontario in the 1830's. Niagara Falls acted as a natural barrier preventing sea lamprey movement to Lakes Erie, Huron, Michigan, and Superior.