Crews search Illinois River for invasive fish

CHANNAHON, Ill. Beneath the muddy waters of the Des Plaines River are a variety of fish, including gar, buffalo or common carp. What may be living among the fish are Asian carp known as big head or silver carp.

"Asian carp came from catfish farmers in Arkansas in the southeast, and during storms they escaped and headed into the first stream, and then to larger streams, and finally into the Mississippi River. They made a right-hand turn and headed up the Illinois River," said Pam Thiel, U.S. Fish and Wildlife Service.

In recent years, the Asian carp have been moving north. The goal is to keep them out of Lake Michigan so they do not ruin a $4 million recreational and commercial fishing industry. Asian carp are a danger because they jump and they will out-compete native fish for food.

"Once they get over 12 inches, we don't have any native fish that can eat them, so they just continue to grow," said Thiel.

Once a year, the U.S. Fish and Wild Life Service and the Army Corps of Engineers look for Asian carp to track their movements.

"We need to figure out what their movement rates are and what kind of habitats they're using, and how fast they're getting through these pools," said Kelly DeGrandchamp, U.S. Army Corps of Engineers.

Trolling for carp is done by using electric sensors. If one is caught, researchers implant ultrasound transmitters inside the fish, and then throw them back in the water to track their movements.

"It's actually real surgery. We'll make an incision and insert the tag, suture the fish, get the wound shut, and actually put superglue on the fish's skin to form a water tight seal," said DeGrandchamp.

But after two hours of trolling, on this trip, surgery wasn't necessary, because no Asian carp were found, which is a good thing.

"We kind of expected them to be a little bit more abundant, based on the last couple of years and the progression from pool to pool, so the fact that they're not here is good news, and it tells us that perhaps they're choosing not to be in these upper pools," said Thiel.

But the search is not over. The hunt for Asian carp continues all week.

If you are fishing north of Joliet and see an Asian carp, the U.S. Fish And Wild Life service asks you to contact the agency or the U.S. Army Corp of Engineers.

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