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
Thames and Severn Canal navigable state. The condition of the canal continued to decline. Complaints were made about its state in 1874 and 1885, which resulted in surveys being undertaken, but little was done to remedy the situation. In 1893, the Thames and Severn company announced that the canal between Chalford and Inglesham would close two days later. Negotiations with a number of interested parties took place, and having given an assurance that it would not be converted into a railway to the Great Western Railway, an Act of Parliament was obtained in 1895, which formed a Trust with powers to raise £15,000. The