Contact(s): Dan Oele, DNR fisheries biologist, 608-275-3225; David Rowe, DNR Fitchburg Area Fisheries Supervisor, 608-275-3282; Pete Jopke, Dane County Land and Water Resources Department Water Resources Planner, 608-224-3733
MADISON - The Wisconsin Department of Natural Resources in cooperation with the Dane County Land and Water Resources Department will implement a project to remove common carp and restore the fishery of Indian Lake in the town of Berry in Dane County. This project is tentatively scheduled for the week of Oct. 15, 2018 assuming favorable weather conditions.
Consistent with recommendations made in the 2013 Indian Lake Management Plan, Indian Lake will receive a rotenone treatment to remove common carp populations. Carp have negatively impacted the aquatic plant community, which has resulted in poor water quality conditions with blue-green algae blooms and summer fish kills of desirable gamefish species. Carp became the dominant fish species in Indian Lake after a winterkill event in 2010.
The plan is to treat Indian Lake with PrenfishTM Fish Toxicant (5 percent rotenone active ingredient) at a concentration of 3.0 parts per million the week October 15, 2018 to eradicate all fish including common carp. Once the treatment is completed, the lake will fill to normal levels and we will restock the lake with largemouth bass, bluegills, channel catfish, and forage minnows like fathead minnows and golden shiners.
To maximize the effectiveness of the treatment, the lake will be temporarily drawn down 1 to 3 feet to concentrate the carp while dewatering shallow, complex nearshore environments. The drawdown will isolate the rotenone and it will not flow downstream. The rotenone will be delivered via an aerial application using a contracted helicopter and will take approximately 8 hours to complete.
Rotenone is a botanical product that has a long history of proven effectiveness in rehabilitating shallow lakes. Rotenone is a specific compound that interacts with the gill membranes of fish and does not have any impacts to mammals, birds, or reptiles. Given the warm water temperatures, turbidity of the lake, and photo-degrading nature of the product, the rotenone is expected to remain active for about 24 hours, dependent on sunlight and temperature.
The park is expected to be closed to public access for 1 full day during the rotenone treatment. Before treatment, access points to Indian Lake will be posted with informational placards that will remain for the duration of the treatment. Recreational access (e.g., wading, swimming, boating, fishing, etc.) within the treatment area on Indian Lake will be prohibited while the lake is being drawn-down and rotenone is being applied. The rest of the park will be open after the aerial application is completed.Swimming or wading by humans or pets will be prohibited in treated water while placards are displayed. Fish should not be consumed from Indian Lake while placards are displayed.