MADISON, Wis. (AP) — Wisconsin authorities thought they could curb libidos at the state’s nude beach by closing it on weekdays, but citation data shows the move just shifted the hanky-panky to the weekends.

The Department of Natural Resources issued 13 citations at the beach between June and early October this year. All were for sex, and 11 were issued on weekends. Those numbers are down from 2012’s totals, but wardens said the problem is far more prevalent than the numbers suggest. All the citations were issued during just seven days of surveillance and some people seen having sex ran off before wardens could cite them.

“There’s no doubt there’s more stuff going on,” said Nathan Kroeplin, who supervises DNR law enforcement in Dane County. “There’s definitely frustration. (The weekday closures) didn’t really seem like it made that much of a dent.”

The DNR has owned the beach on the Wisconsin River just outside Mazomanie and the surrounding woods since the late 1940s. Over the years, the sandbar has become a destination for nudists from around the country. Exposing one’s genitals is a misdemeanor in Wisconsin, but prosecutors in liberal Dane County say naked people must cause a disturbance before they’ll charge them. The DNR estimates as many as 70,000 people have visited the sandbar some summers.

The trouble is visitors haven’t been content with skinny-dipping and sunbathing. Many are looking for trysts and drugs, according to the DNR.

The agency has been trying to put the kibosh on the bad behavior for more than a decade. In the late 1990s, it closed the beach at night, banned camping on the beach and installed a gate to block vehicles and halt drive-in, drive-out trysts. In 2007, it closed sections of the surrounding woods and cut down brush near the beach to eliminate cover for sex.

But arrests for sex and drugs hit a five-year high in 2011, when wardens arrested 42 people in nine days of surveillance. Last year, the DNR closed another 70 acres around the beach, but it had little effect; wardens issued 22 citations — most for sex — in less than a week of surveillance.

This spring the DNR decided to close the beach on weekdays from March through mid-September. Agency officials theorized people were more likely to commit offenses during the week when fewer people were around. But the larger weekend crowds didn’t police themselves as hoped.

“Some of the stuff we cited people for was fairly discreet,” Kroeplin said, “but there was other stuff out in the wide open and never once did I see somebody come up and say ‘stop that.'”

A message left with the Oshkosh-based Naturist Action Committee, which advocates for nudist recreation on public lands, wasn’t returned. Friends of Mazo Beach, a group NAC formed to protect nudists’ rights to use the beach, didn’t respond to an email seeking comment.

It’s unclear what the DNR might do next. Kroeplin said officials will discuss the situation this winter and likely close the beach on weekdays again next summer. But the agency doesn’t want to cut off access completely.

“That would be a pretty big step and I don’t know if we’re ready to go there yet,” he said. “I don’t think there’s been any decision made on what we’ll do next year.”

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