Great Lakes are estimated at 900 trillion. The influx of parasitic lamprey populations after the development of the Erie Canal and the much later Welland Canal led to the two federal governments of the US and Canada working on joint proposals to control it. By the mid-1950s, the lake trout populations of Lakes Michigan and Huron were reduced, with the lamprey deemed largely to blame. This led to the launch of the bi-national Great Lakes Fishery Commission. "The Great Lakes: An Environmental Atlas and Resource Book" (1972) noted: "Only pockets remain of the once large commercial fishery." But, water quality improvements realized
Great Lakes passenger steamers Lakes) and a high-speed catamaran running between Milwaukee, Wisconsin and Muskegon, Michigan. An international ferry ran on Lake Ontario from Rochester, New York to Toronto from 2004 to 2005, but it was plagued with high operating costs and low demand. The privately owned company was taken over by the City of Rochester, and the ship was sold overseas where it operated across the Strait of Gibraltar. Cruise ship traffic on the Great Lakes increased in the early-21st century, with ships like the MS Hamburg, the MS Saint Laurent and the smaller ships of the Great Lakes Cruise Company offering multi-day