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DNR Finds Evidence Of Asian Carp In St. Croix River

ST. PAUL, Minn. (WCCO) -- The afternoon news conference drew a standing room only crowd. People stood behind a string of television cameras to hear Minnesota Department of Natural Resources Commissioner Tom Landwehr confirm what many have feared. But it was news that nobody wants to face.

The state's long fight to keep the invasive and damaging Asian Carp from infesting its pristine waters is giving up precious ground.

"According to these test results we found 22 of the 50 tests in the St. Croix were positive for Silver Carp. However, none of the tests in the Mississippi river were positive for Asian Carp," Landwehr said.

That's the only silver lining to a very dark and ominous cloud. The leaping Silver Carp have already taken over waterways like the Illinois River and most of the waterways south of there. They spread rapidly and can quickly force out native game fish by their voracious appetites.

"They're planktivores and if they take all the food that smaller fish eat, which are eaten by bigger fish, it just goes up the food chain and it will change the dynamics of what happens in a river," said Byron Karns, a national park service biologist,

On June 28, a contractor working for the DNR took 50 water samples from the St. Croix River between Prescott, Wis. and St. Croix Falls. The following day, another 50 water samples were collected from the Mississippi river downstream of the Lock and Dam at the Ford Parkway. While the Mississippi sampling turned up no evidence of Asian Carp DNA, an indication the fish are present sampling from the St. Croix is cause for alarm.

"The DNA is sloughed off the fish from excrements and mucus and it persists for a little while in the water and floats," said DNR River Planner Tim Schlagenhaft,

While the samples are not 100 percent conclusive and could be an indication of a hatchery or fish food upstream, that is highly unlikely. The DNR said it knows of no such fishery using a fish food containing the DNA.

The test results will apply new pressures on state regulators to speed up its Asian Carp battle plan. That can range from the construction of electric or physical fish barriers to emergency closure of a lock and dam. That drastic action would require action from Congress to interrupt navigation.

"Let's explore what existing technologies are available as far as physical barriers and discuss how the lock and dam system relates. That's a robust part of that," said Paul Labovitz, superintendent of the Mississippi National River & Recreation Area,

In the meantime, the DNR is working to contract commercial fishing companies to begin test netting the St. Croix to get concrete evidence of the Silver Carp's presence and numbers.

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