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FOR IMMEDIATE RELEASE: 2020-09-22

Contact: Lt. Robert Stroess, DNR administrative warden
Robert.Stroess@wisconsin.gov or 920-901-1361
Lt. Stefan Fabian, DNR law enforcement supervisor
Stefan.Fabian@wisconsin.gov or 920-366-2802
Joanne Haas, DNR program and policy analyst
Joanne.Haas@wisconsin.gov or 608-209-8147

First-Ever Invasive Carp State Case: DNR Investigation Shows Illegal Sales In Madison

A grass carp, one of Wisconsin's most prominent and highly-destructive invasive species, swims in a river. A grass carp, one of Wisconsin's most prominent and highly-destructive invasive species, swims in a river. Photo credit: iStock/ Wrangel

MADISON, Wis. – A wholesale fish dealer from Platteville is facing state charges for allegedly illegally selling Asian carp, Wisconsin’s most prominent and highly destructive invasive species.

The charges against the operator of Li Fish Farm, LLC, a Grant County-based fish company, is the first case involving illegal sales of Asian carpA complaint from a member of the public sparked an investigation by the Wisconsin Department of Natural Resources.

These types of Asian carp, bighead, silver and grass, are different from the carp commonly known as German carp, which have lived in Wisconsin since the mid-1850s.

The fish farm operator is facing four criminal charges of Possess Illegal Fish and a fifth charge of Violate Vehicle ID Requirements when Transporting Fish. The case is pending in Dane County Circuit Court system. Additional pending citations for similar violations are expected from the DNR Bureau of Law Enforcement.

The Conservation Warden investigation focused primarily on activities during 2018 and 2019. However, the alleged illegal fish activities were ongoing for several years before.

“These types of carp are highly invasive species that out-compete Wisconsin native fish species and can destroy their habitats,” said Lt. Robert Stroess, DNR warden administrator for Commercial Fishing, Wholesale Fish Dealing and Charter Fishing Enforcement. "The species is top on the Least Wanted Aquatic Invasive Species List from the Great Lakes – St. Lawrence Governors and Premiers."

Specifically, the list cites these threats for each type of carp:

  • The bighead carp as a feeder of plankton, which is a primary food for many native fish including walleye, yellow perch, lake whitefish and all juvenile fish. This specific carp is known as a major threat to the Great Lakes $7 billion fishing industry.
  • The silver carp as another feeder on fish habitats attacked by the bighead. This species also is known to leap out of the water, which is a threat to boaters and the region’s $16 billion boating industry.
  • The grass carp eats aquatic habitats and is known to help cause algae blooms and damage to wetlands and waterfowl habitats.

In Wisconsin, the invasive carp species must be either eviscerated (gutted) or have the entire gill covering severed. This requirement exists because these carp species have been known to survive out of water for up to a day or longer. Gutting them or severing the gill plate ensures the fish cannot be revived or survive if released into waters.

The investigation found nearly all the carp sold or transported by the wholesale fish dealer on the Wisconsin side of the state line had been completely intact and therefore illegal in Wisconsin. Although the carp were not in water tanks when illegally transported into Wisconsin, the species retains the ability to be revived once returned to water.

“This illustrates why the law requiring this carp species be eviscerated or have their gill covering severed is an important protection of our native Wisconsin fish,” Stroess said.

Other violations include operating a wholesale fish dealer vehicle without having it marked in any way to indicate it contained fish and failing to create or maintain required records. Records are essential for being able to trace fish back to the commercial fisher who caught the fish or to the business who sold the fish, especially for species that are highly regulated. 

To learn more about the Great Lakes – St. Lawrence Governors and Premiers Least Wanted Aquatic Invasive Species List.