Researchers use 'Judas fish' to battle invasive carp

The common carp typically congregates in the cold weather, providing an excellent opportunityfor Peter Sorensen to conduct his research.

"These fish are smart, fast, and wile," says Sorensen, director of the U of M's Aquatic Invasive Species Research Center.

Sorensen is continuing his research this winter on a handful of metro area lakes. It's research that could be critical if Asian carp make a more regular appearance in Minnesota rivers and lakes.

Using what he calls a "Judas fish" technique Sorensen and his team tag common carp with a radio frequency device and in turn, that fish leads them to larger schools.

"We release them into the water and they find each other pretty quickly," says Sorensen. "We basically have the Judas fish lead us to the others.

At that point crews net hundreds of the carp in an effort to restore the lake's ecosystem. This week, Sorensen will use Staring Lake in Eden Prairie as his next laboratory.

The hope is that the "Judas Fish" technique could help locate Asian carp before they get a foothold in Minnesota's prized lakes, rivers and streams.

The DNR is closely monitoring the study.