Minnesota boaters will see more conservation officers handing out tickets and warnings this weekend at lakes and rivers across the state, thanks to an increasing rate of boaters violating state laws.

The ramped-up enforcement announced Thursday aims to slow the spread of zebra mussels and other aquatic invasive species, which have infected more than 175 waterways across Minnesota. Despite laws made to better protect lakes increased four years ago, the state Department of Natural Resources says many boaters still aren’t getting the message.

“We’re kind of in the part of the summer where complacency takes over,” said Capt. Greg Salo, DNR enforcement manager. “[They are] very simple rules; it’s just kind of a culture change for everybody.”

New numbers released Thursday show that one in four boaters checked by officers aren’t following the rules so far this year, whether it’s removing the boat’s drain plug when transporting it or not emptying out bilge water that could hide microscopic zebra mussels. That 26 percent violation rate is more than last year’s 20 percent rate.

“All it takes is one [contaminated boat],” Salo said at Riverfront Regional Park in Fridley. “Not all of Minnesota is infested. It’s still worth the fight.”

This weekend’s enforcement sting is part of extra efforts this year to try to curb the spread of aquatic invasive species. The DNR has authorized more local watercraft inspectors and boosted the number of check stations to 36 — twice as many as last year.

It’s all in hopes of boosting compliance and reminding boaters to empty bait buckets and live wells, and remove weeds and other debris from boats, trailers and equipment.

For avid anglers like Josh Link of Edina, it’s becoming a reluctant new way of lake life. While it takes up time he and other anglers would rather spend fishing, he said the checks are needed.

“To be honest, it’s kind of annoying, but I get it,” Link said Thursday as he prepared his line for bass fishing on Lake Minnetonka. “It’s the same as not littering. You have to take care of the resources.”

Many of Minnesota’s 2.3 million boaters are doing just that. On Thursday, the DNR said most of the 78,000 boats inspected locally and by the DNR inspectors so far this year have followed the rules. But inspectors, who can’t issue citations, checked 1,300 boats that had invasive species on them.

DNR conservation officers, who can issue citations, have given out 375 warnings to boaters for violating rules and issued 169 citations — which can range from $100 to $500 in fees and could mean jail time if cited for a misdemeanor. That’s actually fewer warnings and tickets than last year, but Salo said that’s because fewer people are boating this year due to high water and wake restrictions at dozens of lakes like Minnetonka.

At Grays Bay, Troy and Tania Hummelgard of Andover were about to drop their boat in the no-wake lake when DNR inspectors reminded them to remove the drain plug when they transport the boat — a rule the couple said they didn’t know about.

“I guess it’s something we should be aware of,” Tania Hummelgard said.

They’re not alone; it’s the No. 1 issue DNR inspectors see with boats since the drain-plug law was passed in 2010.

“It’s not a big deal if it keeps the water clear,” Troy Hummelgard said.

New rules too late?

The first two years after that year when the DNR ramped up laws like the drain plug rule, officers didn’t give out tickets often, Salo said. But now, with the compliance rate not budging, he said it’s necessary.

“The tickets are the incentive to change the behavior,” he said.

The risk of not emptying out water or removing weeds can mean spreading zebra mussels, which can attach to boats, docks, rocks, native clams and other solid surfaces, proliferating by the millions. They grow only to fingernail size, but can clutter beaches with razor-sharp shells, clog motors, change habitat for fish and insects, and jam intake pipes for water and power plants. And while they’re the poster child for the invasion, there are many more species not yet in Minnesota.

The DNR announcements about the discovery of invasive species in a new body of water have become almost routine. Recently, zebra mussels were detected in Lake Melissa — the first confirmed sighting in the Detroit Lakes area, a popular summer destination for boaters and anglers. Infested waters also include popular lakes in the Brainerd area, Lake Mille Lacs, Lake Minnetonka and Minnehaha Creek.

In May, Gov. Mark Dayton signed a tax bill for an additional $10 million per year to help local governments combat zebra mussels and other aquatic invasive species.

But some boaters, including Bill Bennett of Plymouth are skeptical, worried that the efforts come too late.

“I thought it looked like they were turning it [enforcement] into a moneymaker because they have long lost the lakes,” he said of being cited for having a weed on his boat even after he did a thorough check.

However, he said, he supports the efforts, especially after hearing about cases like a boater headed to Voyageurs National Park, near the Boundary Waters, with a wakeboard that had yet to be decontaminated from two months on Lake Minnetonka.

“Overall, I hope it’s well intended,” he said of enforcement. “I don’t want the Boundary Waters to get screwed up.”