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Contact: Lt. Robert Stroess, DNR Administrator of Commercial Fish and Aquatic Species in Trade Enforcement

DNR Crayfish Case Nets First Criminal Convictions Under Wis. Invasive Species Law

Wisconsin DNR news release

MADISON, Wis. – The Wisconsin Department of Natural Resources (DNR) today announced the first-ever criminal convictions under the state’s invasive species law, Chapter NR 40, related to the importation of live red swamp crayfish.

Although red swamp crayfish are native to the southern U.S., they are not native to the northern U.S., including Wisconsin, Michigan and Minnesota.

“These crayfish are illegal in Wisconsin because they cause havoc in our waterways by out-competing other species, damaging shorelines, and burrowing deep into the ground to avoid winter freezing,” said Lt. Warden Robert Stroess, DNR Administrator of Commercial Fish and Aquatic Species in Trade Enforcement. “They are prolific and resilient.”

The investigation was launched in 2020 after several grocery stores were offering live red swamp crayfish for sale. Then, a walker in Ozaukee County reported an “aggressively acting” crayfish to the DNR. Lt. Warden Stroess tracked the escaped crayfish to a home 340 feet away, where a crayfish boil had taken place a few weeks earlier. Further investigation revealed a significant illegal importation of live red swamp crayfish throughout the Great Lakes region.

The crayfish distributors were sent letters informing them that the red swamp crayfish being shipped was illegal under many jurisdictions. Among those distributors was Louisiana Crawfish Company. The investigation showed that Louisiana Crawfish Company received the letter, confirmed its contents, but then continued to ship nearly 13,000 more invasive crayfish to Wisconsin.

“Try as we may, education and outreach don’t always change the behavior of some individuals and companies,” said Lt. Warden Stroess. “Sometimes enforcement is needed.”

The Wisconsin Department of Justice charged Louisiana Crawfish Company with 15 criminal counts of intentionally transporting, possessing, or transferring invasive species. On Aug. 25, 2022, the Dane County Circuit Court accepted a guilty plea from the company. The court then convicted the company of 10 criminal counts and ordered the company to pay $34,380 in fines, fees and assessments. The plea deal included dismissing the remaining 5 counts.

“Our hope is the outcome of this case can serve as a deterrent to other wholesale distributors to keep invasive red swamp crayfish out of Wisconsin,” said Lt. Warden Stroess.

More information about invasive species in Wisconsin can be found on the DNR’s website.