Invasive bighead carp discovered in Minnesota River

A 25-pound male bighead carp was caught by an angler last week in the Minnesota River near New Ulm — the first confirmation the destructive, invasive species has entered that river.

Minnesota Department of Natural Resources officials acknowledged the catch on Wednesday, saying they were concerned about the potential effects of invasive carp in the Minnesota River watershed but that the capture of this fish didn't mean the creatures were reproducing or establishing a population in those waters.

"We have suspected that bighead carp have occasionally entered the Minnesota River from the Mississippi River," DNR Invasive Fish Coordinator Nick Frohnauer said in a statement confirming the discovery. A grass carp, also invasive, was caught in the same location in December, the DNR added.

Jason George, a crew member with the commercial fish company that caught the carp, said the crew saw something odd but initially assumed it was a catfish. It wasn't until the next day he realized it was something else.

"It was on the surface down in the corner and I knew right away as soon as I seen it that it was something that wasn't supposed to be in there," George said.

Bighead, silver and other invasive carp have been moving upstream on the Mississippi River for decades. The huge fish compete with native species and pose a threat to rivers and lakes, the DNR says. In other states, silver carp, which can leap out of the water, have wreaked havoc on boaters and anglers.

While no breeding populations of Asian carp have been detected in Minnesota waters, individual fish have been caught in the Mississippi near the Twin Cities, in the St. Croix River, and now in the Minnesota River, the department said.

Frohnauer called the Minnesota River discovery "disappointing" but cited several projects around the state designed to stop or frustrate the spread of carp.

The possibilities include using electrictricity or sound waves to stop the movement of fish through the locks and dams.

Scott Sparlin, executive director of Coalition for a Clean Minnesota River, said he wants the invasive species controlled, but says regulators need to be careful about what they do.

"Is there a way to eradicate that fish to a great degree without harming other fish species?" Sparlin asked.

Sparlin is wary of fish barriers. He said they could hurt native fish populations by limiting their access to parts of a river system.

But with the recent discoveries of two invasive carp in the Minnesota River, there's almost certainly going to be more interest in finding a way to stop the species before they become established in state waters. The question is how best to do that.