Stories tagged Asian carp


Asian carp jumping: Asian carp not only take over river ecosystems, but can furiously "fly" out of the water.
Asian carp jumping: Asian carp not only take over river ecosystems, but can furiously "fly" out of the water.Courtesy The Theater of Public Policy
Preliminary information from a study of river water DNA samples done two years ago cranked up concerns about the presence of Asian carp in Minnesota sections of the Mississippi River and also the St. Croix River. But new and deeper analysis of the data shows that the menacing fish haven't been regular residents of those waters, and that local authorities have plenty of time to plan ways of keeping the invasive species away.

What changed? Last year researchers used more precise methods of identifying the DNA, they found that the earlier DNA samples were most likely not from Asian carp.

It's all good news in the short term. The Asian carp have been slowly migrating up the Mississippi River, upsetting the eco-balance of those waters for many years. The fish are aggressive and actually can "jump" out of the water and into anglers' boats. They also are aggressively eating foods that are the diets of native fish.

This new information isn't slowing down plans to try to halt the spread of the fish upstream, authorities added. Among the plans are to install underwater noise and bubble barriers at the Ford Dam on the Mississippi River in the heart of the Twin Cities.


Yesterday, I had the pleasure of attending Environmental Initiative's 2012 Legislative Preview, part of their Policy Forum series.

Basically, a bipartisan group of legislators discussed their environmental priorities with a diverse audience of public, private and nonprofit representatives for the purpose of providing

"a valuable first look at the most pressing environmental issues facing the state in anticipation of the upcoming legislative session."

MN Most Wanted: Asian carp, aquatic invasive species
MN Most Wanted: Asian carp, aquatic invasive speciesCourtesy State of Michigan

The biggest surprise to yours truly was the prevalence of carp among the discussion. Asian carp, AIS (aquatic invasive species), etc., etc.. Everyone appeared in agreement regarding the threat posed by carp, so the real question is what do we do about their impending invasion?

One repeated suggestion was to fund more research, specifically at the University of Minnesota. This is probably an important step towards defending our state waterways, and I think this story helps illustrate why:

"As yet, no technology can stop these downstream migrations; neither grates nor dangerous, expensive electrical barriers do the job.

But a wall of cheap, harmless bubbles just might—at least well enough to have a significant benefit."

Researchers at the U of MN have discovered that bubble barriers may deter 70-80% of carp migration. It's not the visual affect of the bubbles that prevents all but the most daring carp from penetrating the barrier, rather the noise -- equivalent to what you or I would experience standing about three feet from a jackhammer.

The bubble barrier has currently only been tested on common carp, but researchers involved in the experiment want to test the technology on Asian carp next.

In addition to the bubble barrier, U of M researchers are investigating whether Asian carp pheromones can be used to lure them into traps.

Asian Carp
Asian CarpCourtesy kate.gardiner
ScienceBuzz is covering the danger Asian carp present to the Great Lakes. Last week a 19.6-pound, 34.6-inch bighead carp became entangled in a fishing net about six miles from Lake Michigan.

“Asian carp are like cockroaches; when you see one, you know it’s accompanied by many more you don’t see,” said Henry Henderson, of the Natural Resources Defense Council.

You can learn more in The New York Times