DNR to Fishermen: Clean Up or Pay Up

The DNR is using GPS technology and hands-on sleuthing to crack down on ice fishermen who leave litter. Fines are as high as $2,000.

In an early sign that spring is not far away, the state of Minnesota is once again reminding winter anglers that it’s more than bad manners to leave trash on the ice — it’s a crime that carries a financial penalty.

In their annual face-off with littering fishermen, Department of Natural Resources officers are riding snowmobiles and toting GPS receivers to mark the fish houses with messes around them, and they are prepared to slap owners with fines as large as $2,000.

But when the wind pushes trash around the lake, conservation officers such as Adam Block, a cop turned conservation officer in Prior Lake, often end up using less high-tech techniques to track down culprits.

“A lot of the time you end up digging through the garbage bags to find out if there’s anything you can find a name to or a receipt to,” Block said.

To the DNR and those who have lake homes, littering is a serious problem.

Throughout the ice-fishing season, officers find food packaging, beer cans and propane tanks stacked against fish houses and scattered around lakes across the state, said Capt. Ken Soring, the DNR’s northeast region enforcement manager.

But by far the messiest time of the season comes around the state’s deadline for fishermen to pull their houses off the ice, Soring said. In the southern two thirds of Minnesota, that is March 1, and officers expect to find loose insulation, wood blocks and even entire fish houses abandoned on the ice.

Even human waste — sometimes tied up in plastic grocery bags — can be a part of the trash. After all, “people don’t have a bathroom or portable toilet in their fish house,” Soring said.

To reel in littering fishermen as they move their shacks around the lake, DNR officers photograph messy fish houses and mark their GPS coordinates.

“Once the shelter is gone and the garbage is still there, we have an idea of who to talk to,” Block said.

Some anglers help by picking up others’ loose trash and reporting messy houses.

Said Block, “I think a lot of people are starting to police themselves, which is what we want.”

Fisherman Tim Sonenstahl, of St. Michael, said he picks up after others in part because he doesn’t want all fisherman to get a bum rap.

“They don’t want that image that it’s all the fishermen doing it,” said Sonenstahl, 46. “There’s lots of people out [on the lake].” He’s among many fisherman who, after the season is done, troll the ice and do a final cleanup.

“There are trash hogs out here, but there are people on the other side of the fence who want to be able to swim in there during the summer,” Sonenstahl said.

Block said that some of the culprits are people who go to fish houses for reasons other than angling.

“They may not have much of an interest in fishing,” Block said. “But they may be interested in drinking beer.”

For those who ignore the warnings and get tagged by the DNR for littering, the price can be hefty.

Conservation officers can issue criminal citations with a fine of $300 or civil citations with a by-the-pound penalty that can climb to $2,000.

Items such as appliances, batteries and tires can add as much as $100 each to the fine.

Said Block, “[fishermen] put a lot of time into getting these [fish houses] built, and they pay a lot of money to buy them, so they should know the laws. Sometimes it just comes down to laziness.”

Original article from the Star Tribue, February 5th, 2010

Author, Ian Larson is a University of Minnesota student reporter on assignment for the Star Tribune

LAKESMARTS: Controlling Carp to Improve Water Quality

Common carp are an invasive species and are prevalent in Upper Prior Lake and previously in Spring Lake (prior to a very successful seine in 2017 where roughly 70% of the population (17 tons) was removed). Carp can live over sixty years and grow to a length of more than 3 feet! They mature when they are 2-3 years old at which time they are roughly 1 foot in length.

Carp adversely impact water quality by uprooting aquatic plants, stirring up sediments from the lake bottom, and releasing harmful phosphorus, which can lead to algae blooms as well as reduced water clarity. Studies estimate the carp population in Upper Prior is approximately 3.5 times higher than the management level (recommended ecological threshold value for carp is 100 kg/ha).

After the successful seine of Spring Lake, the current carp biomass was calculated at 84.9 (±27.3) kg/ha, which is below the ecological threshold value of 100 kg/ha. Based on electrofishing by the Watershed District, the estimated carp population for Upper Prior is 342.45 kg/ha carp biomass and the estimate for Lower Prior is 9.72 kg/ha carp biomass.

Several important methods are underway to control carp including barriers, physical removal and biological control.


In 2016, the Watershed District began a Passive Integrate Transponder (PIT) tagging project that helped track carp movement. The small, coded wire PIT tags have been implanted in approximately 300 carp. PIT tags allow the District to track carp at all times of day and varying size/age of fish as they travel into or out of specific areas where receivers have been placed. The tags have also allowed the District to identify key areas carp enter during spawning season. The District now installs seasonal barriers in these areas to prevent carp congregation for spawning.

Adult Carp Removal with Seine Nets:

The PIT tagging project has helped to identify carp favorite hangouts during ideal seining seasons. The District anticipates that it will have one or two seine events in Upper Prior Lake over the next year in an effort to remove a significant portion of the population. This should help provide some significant water quality improvements in Upper Prior Lake.

Biological Control:

Young carp survive poorly in lakes that have abundant bluegill population. In fact, the Minnesota Aquatic Invasive Species Research Center (MAISRC) has identified that bluegills can control carp populations by consuming carp eggs and larvae, and thus limiting survival of offspring. The University of Minnesota is conducting studies on the relationship between bluegill and carp in hopes of determining appropriate bluegill stocking levels as an ongoing potential carp management tool.

Carp Management is a multi-level and multi-organizational effort. The Watershed District hopes to successfully seine carp during the winter months. Barriers will be in place during spawning season and, ongoing research will provide us with data regarding the appropriate levels of bluegills for ongoing efforts of keeping carp levels well managed. Data from water quality monitoring of a nearby wetland area shows that the water going into this body is cleaner than the water going out during carp spawning season. The Prior Lake Association will continue to provide the community with updates on this massive effort as well as others that are implemented with the goal of improving the quality and clarity of our waters.

Sources: Minnesota DNR, Minnesota Aquatic Invasive Species Research Center and the Prior Lake-Spring Lake Watershed District