Could bighead carp's arrival change Rock River forever?
Written by Rockford Register Star   
Sunday, 28 August 2005 18:15
The discovery of an Asian bighead carp in the Rock River at Rockford's Fordam Dam produced a boatload of questions, concerns and even a couple of suggestions for a possible solution.

An angler walked into the Rockford Bait Shop, 2822 11th St., last Sunday with a fish he couldn't identify. Store owner Bob Rhodes determined it was a bighead carp and photographed the fish. Dan Sallee, the state Department of Natural Resources regional fishery administrator, confirmed it was a bighead after viewing the photos.

The Rock River has joined the growing list of U.S. waterways invaded by the dreaded Asian fish. They're unwelcome because they multiply quickly, compete with native species for food supplies and damage habitat.

The one found in the Rock River was 22 inches and weighed about 7 pounds, but they can grow much larger. A 50-pounder was caught near the Quad Cities.

Wildlife officials hope the Rockford fish is a single bighead and not part of a breeding population in the Rock that will change fishing on the river forever.

Good idea gone bad

Asian carp were brought to the United States in 1972 from Eastern China by a private fish farmer in Arkansas to control plankton in his ponds. Other farmers thought it was a good idea and bought Asian carp, too.

The species escaped into waterways during flooding in the 1980s and '90s, and began migrating up the Mississippi River and its tributaries. Within the past decade they also started appearing in greater numbers on the Illinois River.

As they moved farther north, officials became concerned about the Asian carp invading the Great Lakes.

The federal and state government jointly are paying for a $9.1 million electric barrier being built in Chicago to keep the carp from entering Lake Michigan through the Illinois River. And similar projects have been considered elsewhere to stop -- or at least slow -- the spread.

A National Aquatic Nuisance Species Task Force panel met last week in Nashville, Tenn., to create an Asian carp management control plan, scheduled to be finalized this fall.

"They have sifted through a lot of ideas," said Jerry Rasmussen of the U.S. Fish and Wildlife Service office in Bettendorf, Iowa. "A lot people are trying to address this. We are running into lots of problems with reproductive capabilities of these fish, the size they get to, and the material they eat."

From Rock to cat dish?

After reading Tuesday's Register Star story about the bighead caught in the Rock, Gerald Rilling of Machesney Park offered a suggestion to cut into the carp population.

He called for a blitz of telephone calls to petfood companies, urging them to buy carp from commercial fishermen for catfood.

"Who is going to listen to one guy," he said. "But if the companies get a bunch of different people calling in they might look into it. ... It would be a win-win situation."

Rasmussen said at least one catfood-producing company did consider using carp. Unfortunately, Asian carp are too high in calcium for cats to digest.

Tom Matych, coordinator of the Muskegon Heights (Mich.) Eagles' adopt-a-walleye program, offers a much more radical approach to stemming the carp invasion.

He suggests the DNR remove as many fish as possible through electro-fishing. Those fish would be placed in a holding facility while a fish-killing chemical is put in the river that would wipe out the Asian carp. Matych believes 90 percent of the native fish could be removed by shocking the river.

"What we are trying to do has never been done on this scale," he wrote in an e-mail Wednesday, "but we have never had an army of giant carp to deal with. I would point out the carp have no restrictions, we cannot get in this fight with handcuffs on."

Sallee discounted that proposal, saying electro-fishing is only effective enough to remove a small percentage of the native species from the Rock River.

"The problem with any plan to remove (bighead carp) is we don't know the extent of their population in the Rock River and how quickly they would recontaminate," Sallee said.

Matych's group is battling the invasion of goby, another exotic species, in Muskegon Lake. The club sponsored a Goby Assault Party in June and removed 5,000 of the fish. A similar fishing tournament is being conducted in Bath on the Illinois River to remove silver carp.

Rasmussen noted at least one Illinois commercial fisherman was trying to establish a foreign market for the Asian carp meat.

Another possibility is finding a company to buy the carp from commercial fishermen and grind up the fish for fertilizer.

"People are pulling out all the stops looking for possible solutions," Rasmussen said.

Wildlife officials won't likely consider importing another fish that would be a natural predator for Asian carp. "We've very reluctant to bring in another species. That's another problem in the making," Rasmussen said.

How it reached the Rock

No one is sure how the bighead carp made its way to the Fordam Dam in Rockford. But Sallee and Rasmussen have a fairly good idea.

Here's a couple of possibilities:

The fish migrated from the Mississippi River over five Rock River dams to Rockford. Sallee said this was possible.

The fish was dumped in the Rock by an angler when it was small and resembled a gizzard shad. Rasmussen said some anglers will net gizzard shad along the Mississippi and use them for bait. Sometimes small bigheads will be among the shad, and when the fishermen throw their unused bait in another river, such as the Rock, they are spreading bigheads.

That's why anglers are asked to dump their bait buckets on the shore.

The fish could have been placed in the Rock as an adult. Some Asian religions urge their followers to release a fish in a river for every fish they eat, Rasmussen said.

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