EDEN PRAIRIE, Minn. (WCCO) – By most measures, Eden Prairie’s Staring Lake is a dead lake – native game fish have been crowded out by an overabundance of common carp.
Now, those fish have become the guinea pigs in a research project aimed at controlling their leaping cousins.
“The big issue with Asian carp is that we don’t know how many there are, or where they are,” explains University of Minnesota fisheries researcher Peter Sorensen.
The director of the newly formed Minnesota Aquatic Invasive Species Research Center at the University of Minnesota is using Staring Lake as an outdoor laboratory.
Environmental DNA (eDNA) testing done by the Department of Natural Resources has shown evidence that invasive Asian carp are already in Minnesota, both in the Mississippi and St. Croix rivers near the Twin Cities.
But finding them has been tough if not impossible. Commercial fishermen have been hired to net the rivers but haven’t had any luck.
And that’s where Sorensen’s theory and research comes in. He says that if you can locate the schools of Asian carp, you will stand a much better chance of targeting them for eradication.
“They seem to be actually exceptionally social, they really hang out together,” he said. “That’s the premise. We have to confirm that, but it sure looks that way.”
Using radio telemetry, his team of researchers have planted Staring Lake with common carp tagged with tiny radio transmitters. By tracking their “pings” under the ice, the so called “Judas fish” give commercial netters a more accurate location of the larger school of fish.
After several hours of laying out thousands of feet of net under the frozen surface, crews pull the seine in. Soon, the water boils with activity as the carp toss about.
Still, more testing will be needed before Asian carp are targeted by similar “Judas fish.” An effective and sound way to sterilize Asian carp for release has yet to be developed.
Says the research center’s associate director Becca Nash, “this is an example of just what basic information can tell us about how to effectively and efficiently manage an invasive species.”
Said Sorensen, “they’re not an easy thing to chase — they don’t want to be caught.”