fishing practices caused the lake trout populations to decline drastically. The relationship between predators and prey in the Great Lakes' ecosystem then became unbalanced. Each individual sea lamprey has the potential of killing 40 pounds of fish through its 12–18 month feeding period. Efforts at control Control efforts, including electric current and chemical lampricides have met with varied success. The control programs are carried out under the Great Lakes Fishery Commission, a joint Canada–U.S. body, specifically by the agents of the Fisheries and Oceans Canada and the United States Fish and Wildlife Service. Genetic researchers have mapped the sea lamprey's genome in the hope of finding out more about evolution; scientists trying to eliminate the Great Lakes problem are coordinating with these genetic scientists, hoping to find out more about its immune system and fitting it into its place in the phylogenetic tree. Researchers from Michigan State University have teamed up with others from the Universities of Minnesota, Guelph, and Wisconsin, and others in a research effort into newly synthesized pheromones. These are believed to have independent influences on the sea lamprey behavior. One group of pheromones serves a migratory function in that when they are made by larvae, they are thought to lure maturing adults into streams with suitable spawning habitat. Sex pheromones emitted from males are capable of luring females long distances to specific locations. These pheromones are both several different compounds thought to elicit different behaviors that collectively influence the lampreys to exhibit migratory or spawning behaviors. Scientists are trying to characterize the function of each pheromone, and each part of the molecules, to determine if they can be used in a targeted effort at environmentally friendly lamprey control. However, as of 2017, the most effective control measures still involve the application of (3-trifluoromethyl-4-nitrophenol), or TFM, a selective pesticide, into rivers. no lampricide resistance has been detected in the Great Lakes. Further research and combined use of multiple control methods are needed to forestall future development of resistance. Another technique used in the prevention of lamprey population growth is the use of barriers in major reproduction streams of high value to the lamprey. The purpose of the barriers is to block their upstream migration to reduce reproduction. The issue with these barriers is that other aquatic species are also inhibited by this barrier. Fish that use tributaries are impeded from traveling upstream to spawn. To account for