Federal authorities will apply specially designed poisons to the Betsie River system in Benzie County this month to kill invasive sea lamprey larvae burrowed in the stream bottom.
The U.S. Fish and Wildlife Service says the lampricides will be placed in the waters between June 17-21.
Sea lamprey are eel-like parasites that attach themselves to fish and suck out their bodily fluids. They live in stream sediments during their larval stage, the period that offers the best opportunity to kill them. Infested tributaries must be treated every three to five years to keep lamprey numbers under control and avoid significant damage to fish populations.
Officials say the lampricides pose no unreasonable risk to people or the environment at concentrations necessary to kill larval lampreys.