Agencies Aim to Catch Invasive Carp

Scientists from the U.S. Geological Survey, in collaboration with the Minnesota and Wisconsin Departments of Natural Resources, will install floating bait platforms and monitoring equipment to test a new method for capturing invasive carp. The equipment will be in place from July 28 to Oct 3, 2025 in Pool 8 of the Mississippi River, near La Crosse, WI.

Invasive carp, including silver and bighead carp are found throughout much of the Mississippi River basin. These fish pose a threat to native aquatic ecosystems by outcompeting native fish for food and habitat, disrupting food webs and altering water quality. Silver carp, which can jump 10 feet out of the water, can also pose a risk to boaters. Invasive carp are wide-ranging and difficult to capture with traditional fishing gear.

Late summer is a particularly difficult time of year to capture invasive carp in Minnesota-Wisconsin border waters because the fish tend to disperse widely throughout the river. Past trials have shown that baits made from algae attract silver and bighead carps. Floating bait platforms could draw invasive carp into favorable locations to make them easier to capture.

The floating platforms will be equipped with automatic feeders that dispense bait at scheduled intervals. The bait, previously tested in laboratory and field trials, is made from chlorella and spirulina, nutrient-rich algae commonly used in aquaculture. Feeding platforms will be monitored for fish abundance and movement in response to the bait. Commercial fishers contracted by the Minnesota DNR will capture fish before and after baiting periods. The data will help researchers to evaluate bait effectiveness and capture methods.

Precautionary measures are in place to ensure project success and public safety. Community cooperation is appreciated. If you observe damaged property or suspicious activity near the platforms, please contact the Minnesota DNR at 651-587-2781 or invasivecarp.dnr@state.mn.us. Hunting, fishing, and recreation will not be restricted near platforms, but the public is asked not to moor to or stand on them. Boaters are also asked to stay clear of commercial fishing operations that will be taking place around the platforms during the weeks of Aug 4 – 8, Sept 2 -5, and Sept 30 -3.

This project is supported by a 2023 Minnesota state legislative appropriation for invasive carp prevention and management, Upper Mississippi River Invasive Carp Grants administered by the U.S. Fish and Wildlife Service and the U.S. Geological Survey Ecosystems Mission Area, Biological Threats & Invasive Species Research Program.