ALEXANDRIA — Another round of carp removal took place at the south shoreline of Lake Winona on Wednesday, Oct. 26.

A total of 1,611 carp were removed totaling 8,460 pounds.

"After removing 30,000 plus pounds last year, we anticipated a lower quantity of carp harvested this go round," said Scott Gilbertson, executive director for Alexandria Lake Area Sanitary District (ALASD).

Last year, a physical carp barrier was installed to prevent the migration of more carp into Lake Winona from Lake Agnes.

This is the second time the ALASD teamed up with Stantec — an engineering company that focuses on environmental issues — and WSB — an environmental project company that uses engineering, ecosystems, and social impacts to manage environmental need. Fishermen from Miller Fish Company in Browns Valley also helped remove the invasive fish.

According to Gilbertson, removal of the carp is necessary because they cause "water quality problems through their feeding and nesting behaviors, which disturb sediments causing the release of phosphorus from the sediments and increased turbidity."

Gilbertson added that carp can destroy native aquatic plant vegetation, which is vital for quality habitat by other aquatic organisms.

"Consequently, carp negatively impact native, desirable fish populations through resource competition and habitat degradation," he said. "These impacts are particularly impactful in shallow lakes with high carp population density so lowering their density to the target threshold is necessary to improve water quality and meet TMDL (Total Maximum Daily Load) goals."

Lake Winona's maximum depth reaches 38 feet, according to lake-link.com .

According to the Minnesota Pollution Control Agency's website , "TMDL is the maximum amount of a pollutant a body of water can receive without violating water quality standards, and an allocation of that amount to the pollutant's sources."

The removal was accomplished through seine net fishing — a method that uses a net, which hangs vertically in the water with its bottom edge held down by weights and its top edge buoyed by floats to surround the carp. Fish tracking devices, driving fish with underwater speakers, and local knowledge of the lake were used to round up the carp.

Once the carp were netted, workers checked for previously attached trackers, then counted and weighed them before transferring them into a live-haul trailer to be shipped across the country.

Gilbertson says Fish H20 delivers and coordinates logistics for distribution in the marketplace, which predominantly includes areas on the East Coast, but may be distributed elsewhere depending on market needs.

After last year's removal, it was reported by the MPCA that it had found PFOS — perfluorooctane sulfonate; a chemical that has been linked to cancer— in carp taken from the lake.

In a 2021 Echo Press article, it was reported that PFOS was found in Lake Winona sunfish and that the Department of Health issued an advisory to men and boys over 15 and women planning on becoming pregnant to limit consumption of the fish to one meal a week.

When asked about the findings, Gilbertson said that the "forever chemicals" referenced are found in numerous household goods, from microwave popcorn bags and fast food wrappers to fabrics in household furniture and cooking pans.

"Unfortunately, they can also be in our waterways and aquatic organisms," Gilbertson said. "It's long been established that fish can bio-accumulate pollutants such as mercury and PCBs, unfortunately, which have necessitated fish consumption advisories across state and federal levels. Consequently, existing state and federal fish consumption advisories and guidance for fish apply."

Jim Kelly, who manages the Minnesota Department of Health programs that include the fish consumption advisory, was quoted in that same Echo Press article saying, "It is difficult without further testing to determine whether people should limit their consumption of carp from Lake Winona." As it is being sold in other states, he said that will likely be up to the health departments in those states.

The removal cost nearly $18,000, paid for by an LCCMR grant (Legislative Citizen Commission on Minnesota Resources). Gilbertson said it covers the established adaptive management approach to improving water quality in the Lake Winona-Agnes-Henry chain.

"The adaptive lake management activity — alum treatments, carp harvesting, carp barrier installation — have been completed per ALASD’s permit requirements with the Minnesota Pollution Control Agency," said Gilbertson. "ALASD future tasks involve monitoring the lakes to track any improvements or regressions that may occur."

After the data of the removal is further examined by ALASD, it will determine if a future removal is necessary. For now, ALASD will continue the ongoing Facility Plan process to guide future improvements of the existing ALASD Wastewater Treatment Facility.