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 to apply for additional federal research and education funds allocated to these national resources. Following a small uproar, the Senate voted to revoke the designation on March 24 (although New York and Vermont universities would continue to receive funds to monitor and study the lake). In the early years of the 21st century, water levels in the Great Lakes were a concern. Researchers at the Mowat Centre said that low levels could cost $19bn by 2050. Except when the water is frozen during winter, more than 100 lake freighters operate continuously on the Great Lakes, which remain a major water