SAULT STE. MARIE, Mich. (Michigan News Source) – The Great Lakes Fishery Commission will be treating for sea lampreys in the U.P.’s Tahquamenon River this weekend.

If left unmanaged, the lamprey will mature into parasitic juveniles. Each one can kill up to 40 pounds of fish during that stage, and the adults can lay up to 100,000 eggs.

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Officials say the river might appear slightly yellow during the treatment. However, the water is still safe for humans and pets. Recreation and fishing are also still safe during the process.