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 Chemical Corporation oil and gas, instead focusing on the research and production of bromine-based chemicals. At about this time, the company assumed its current name (Great Lakes Chemical Corporation) and built the world's largest bromine plant in southern Arkansas. Great Lakes grew through the following decades, acquiring several smaller companies in its market and establishing its world headquarters in West Lafayette, Indiana. Among those acquired by Great Lakes was BioLab in 1996, a producer of pool and spa products. The ticker symbol for Great Lakes on the New York Stock Exchange was GLK. On May 22, 1998, Great Lakes spun off their