Carp catch canceled

For years, the Big Sauk Lake Association and WSB Engineering have been fighting Sauk Lake’s carp infestation with a mass netting operation in the spring, when the ice is still frozen. Their 2022 catch removed nearly 80,000 pounds of carp from Sauk Lake, even though the crews had to fight warm temperatures and melting ice. The carp may be getting a reprieve this year, for while the ice remains frozen, the removal site has been flooded due to the sheer weight of all the snow.

A carp removal team came onto the ice the week of March 13, removing about 18 inches of snow for a road and a seining hole where the fish would be corralled. While the crew began laying out nets and using sonar to locate a large carp school, others began drilling the hole, and the area flooded with about six to eight inches of water because of the snow’s weight.

“The next week, a little more snow and wind came in, along with cold weather,” said Jeff Mayer with the BSLA. “The area froze. As the road was reopened, water came up through the crack, creating unsafe conditions.”

Faced with this environment, the ice netting operation was called off for 2023, although there is still a possibility for open water netting as soon as the ice melts. The BSLA remains hopeful the spring netting operation can still be an annual undertaking, weather permitting.

Not completing the spring carp netting will almost certainly prolong the goal of the Big Sauk Watershed Carp Integrated Pest Management Plan, allowing the invasive species to continue negatively impacting the lake’s ecosystem.

“A large amount of carp biomass needs to be removed from the system, far more than one removal event can accomplish,” said Tony Havranek, WSB Engineering senior ecologist and director of fisheries. “Canceling one event doesn’t necessarily make or break accomplishing the goals set forth on the Big Sauk Lake IPM, but it can push accomplishing the goals farther into the future.”

Removing carp biomass is an important implementation task in the Big Sauk Lake IPM, along with collecting additional carp baseline data to better understand their movements to connected bodies of water.

“The existing carp biomass is well above ecologically damaging thresholds,” Havranek said. “Internal phosphorous loading will remain similar to what it was at the end of calendar year 2022, with no ability to reestablish beneficial native vegetation such as wild rice, which would have provided additional habitat for waterfowl and other fish species.”

Another problem facing the carp removal project has been a recent state funding denial. On behalf of the BSLA, the Sauk River Watershed District applied for a $136,718 state Board of Water and Soil Resources grant, funded through the Outdoor Heritage Fund and the Clean Water Fund. The request was denied, so the BSLA board needs to look for other means of financial assistance.

“Not receiving the funding was a big setback for Big Sauk Lake and those who use the lake, residents and non-residents, as well as wildlife,” Havranek said. “Similar to other external water quality and natural resource restoration and protection projects, managing carp on a watershed wide scale in an integrated manner requires multi-year funding. The Big Sauk Lake IPM lays out a plan with activities that will require funding from a variety of sources to complete. The BSLA may be able to fund some of the activities, but funding from local, state and federal partners will be required in order to improve the ecological integrity of Big Sauk Lake and the downstream waterbodies that receive water from Big Sauk.”

Another aspect of the project the BSLA is looking to fund is the carp radio tagging. There are about 100 carp in Sauk Lake with high frequency radio tags, implanted in them on Sept. 28, 2021, which allow the carp to be tracked as they move upstream or downstream as they cross a wire stretched over the water. There are also 10 tagged carp that are being tracked via radio receivers that have a warrantied battery life of 503 days, a period which ended Feb. 13, 2023; they may still last as long as 1,007 days, which would take them up to July 1, 2024.

When it comes to Sauk Lake property owners helping control carp levels, Havranek and Mayer recommend they join the BSLA board. The scale of the carp infestation is so large, and many of the Big Sauk Lake IPM’s activities are relatively sophisticated and require specialized equipment, so removing even hundreds of pounds of carp through hook-and-line fishing and bow fishing are not likely to make much of a difference.

“If you own property on Sauk Lake and are a member, please consider joining the board,” Mayer said. “We will be having a few board members leaving and would like new ideas to make Sauk Lake a better place for all.”

The BSLA board appreciates volunteers who have helped them with their carp removal project so far, including JR Commercial Fishing, Tim Adams and his crew and Jim Retzlaff and Elaine Mitsche at Big Sauk Resort.