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Great Lakes Fish Monitoring and Surveillance

Every year, the scientists from the Great Lakes Fish Monitoring and Surveillance Program (GLFMSP) collect fish from each of the Great Lakes and analyze them for contaminants. This analysis helps determine what trends might be happening in the lakes as well as how the lakes are responding to emerging chemicals in the ecosystem.

This long term monitoring program was established in the late 1970s and has collected top predator fish (lake trout and walleye) from consistent locations in each of the lakes in the fall of every year. Fish samples are collected in a target size range to limit variation in the results and produce high quality data.

Great Lakes Fish Monitoring and Surveillance Program Collection SitesGreat Lakes Fish Monitoring and Surveillance Program collection sites. This map opens to a image.