Minnesota fishery managers and commercial boats will spend much more time on the water this year hunting down and fishing out invasive carp whose populations seem set to explode in the Mississippi River.

The Minnesota Department of Natural Resources updated its carp plan on Thursday for the first time in a decade. The strategy is more aggressive in the way the state will track, monitor and remove the silver, bighead and grass carp that have already made it to Minnesota waters.

But the plan falls short of endorsing a proposal from University of Minnesota scientists and river advocates to install permanent light, sound and bubble barriers at two lock and dam structures in the river.

Lawmakers considered the proposal last year, but opted against funding it as they waited for the DNR to update its overall carp strategy.

The agency said in the plan that it will study the cost and effectiveness of the light, bubble and sound system over the next four years.

Invasive carp have been working their way north up the Mississippi River since the 1970s, when fish farms and sewage treatment managers in the American South imported them from Asia to clean algae.

Some of the carp can grow to more than 100 pounds. They upend native ecosystems by eating up to 20% of their body weight daily. Silver carp, which grow to about 20 pounds, gather in schools and leap out of the water en masse when they’re scared, sometimes injuring boaters and water skiers.

The fish have already overtaken large portions of the Mississippi and its tributaries in Iowa, Illinois and Kentucky, where state and federal taxpayers have spent tens of millions of dollars trying to remove them.

While the DNR said there is still no evidence that the carp are reproducing in Minnesota, sightings and capture of the fish have been increasing exponentially every year since 2018. Fewer than 10 of the fish were caught in Minnesota then. More than 450 were caught in 2023, including a record catch of 323 at once in November near Winona.

Those fish were caught with a strategy that the DNR hopes to continue in the coming years. The agency put tracking devices on a small handful of the invasive carp and released them back into the river. The fish have guided DNR workers and commercial fishing operators to schools and popular gathering spots ever since.

The DNR’s plan would strengthen the agency’s tracking program and partnership with commercial fishing operations.

“Commercial fishing is currently the most effective way to capture invasive carp,” the plan states.

The DNR said it wants to spend more than 100 days a year on the water fishing out carp and sending commercial boats, with their giant seine nets and years of experience, to the small pockets of the river where the tagged fish lead them. For comparison, the agency actively fished for carp a total of 38 days in 2023.

The state would also install 30 more tracking receivers to cover gaps in the river where tagged fish currently go dark on monitors, and would put tracking devices on more individuals.

The state’s plan expresses support for a permanent light, sound and bubble system at Lock and Dam 19 in Keokuk, Iowa. The deterrent system was temporarily installed there a few years ago, while another was added to the Barkley Lock and Dam on the Cumberland River in Kentucky. Carp have already infested those areas and are reproducing on both sides of those two dams.

According to the DNR, early data shows that the systems cut invasive carp passage in half while having no effect on native species, which are less skittish around noise.

The deterrent system could cost between $10 million and $15 million to install in Minnesota. The DNR’s plan doesn’t specify how much it will cost to enhance the state’s tracking and fishing efforts. Many of its programs now have been paid with federal grants or one-time appropriations from lawmakers. The agency said it will need a reliable source of funding.