Asian Carp Threaten Great Lakes

Environmental officials in Illinois plan to dump a toxic chemical into a stretch of the Chicago Sanitary and Ship Canal Wednesday night hoping to keep Lake Michigan safe from a species of massive and voracious fish called Asian carp.

The fish, which can grow to 4 feet long and weigh 100 pounds, are known for their ability to leap up to 8 feet out of the water as motor boats speed by, injuring fishermen. Scientists fear that the fish, which can eat the equivalent of 40 percent of their body weight every day, could damage the ecosystem of the Great Lakes, which is the largest body of fresh water in the world.

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For now, officials say there's nothing to do but kill them.

"We are all very concerned about the threat Asian carp pose to the Great Lakes," said Stacey Solano, spokeswoman for the Illinois Department of Natural Resources.

Officials said the carp are closing in on Lake Michigan, and that's why they plan to poison a 5.7-mile channel south of Chicago to keep the carp from passing an electric barrier that would normally hold them back. Officials will spread a fish toxin called rotenone near Lockport, Ill., hoping to kill the carp. Rotenone kills fish by disrupting their ability to metabolize oxygen.

"The U.S. Army Corps of Engineers needs to take their barrier down for routine maintenance, and to ensure that no carp are able to reach the barrier, we are taking this action to rotenone the canal," Solano told ABC News.

The Army Corps of Engineers built the electric barrier 25 miles from Lake Michigan back in 2002 to protect the waters.

Alien Species

Environmental organizations say the carp need to be kept from crowding other species out of the Great Lakes. The fish, which make up the largest percentage of biomass in some Midwest rivers, have traveled along the Mississippi for nearly two decades. Some conservation groups say all Illinois locks and gateways leading to Lake Michigan ought to be closed.

"If we want our kids and grandkids to know anything remotely like the Great Lakes we have today, we have to stop the carp. The carp will change the lakes permanently," said Jen Nalbone, director of invasion for Great Lakes United. Her group says Asian carp have had a devastating effect on the Mississippi -- and must be stopped from doing the same thing to the Great Lakes.

Asian Carp Threaten Great Lakes

There is concern that the carp could decimate the $7 billion sport fishing industry and the $10 billion recreational boating industry in the Great Lakes.

"The calm that we are accustomed to and enjoy on the Great Lakes just might not be there," said F. Ned Dikmen, publisher of Great Lakes Boating magazine. "I've seem (the carp) get agitated with boaters and they jump on boats. I've seen people break their jaws. I've seen some real damaging side effects of this fish."

Michigan Governor Jennifer Granholm and Lt. Gov. John Cherry sent a letter to state Attorney General Mike Cox, urging him to pursue every legal means to prevent Asian carp from entering the Great Lakes. "The Great Lakes' ecosystem is at risk and because of the importance of the Great Lakes to Michigan's economy," they wrote.

Nalbone said 80 percent, by weight, of the fish in the Mississippi basin are Asian carp -- and that's dangerous, not only because of the risk to boaters but also because the carp push out native species. "They harmed the Mississippi waterway and we have every reason to expect they will harm the Great Lakes watershed as well," she said. "It will change the lakes the way Zebra mussels changed the lake."

Zebra mussels are black and white-striped mollusks believed to have caused millions of dollars of damage in the Great Lakes region by getting into facilities that use raw surface water. The mussels clog water intake pipes, wells and screen systems.

Nalbone says a permanent hydrologic separation is needed between the Great Lakes and the Mississippi basin where the carp live. "We need to re-establish the natural watershed barrier between the Mississippi basin and the Great Lakes. We are working to push federal agencies to take every needed action to prevent the carp from getting into the lake."

200,000 Pounds of Fish

In what is expected to be an extensive cleanup operation involving hundreds of people from state and federal agencies, officials will collect and dispose of roughly 200,000 pounds of dead fish. Scientists will conduct tests on the fish, hoping to find Asian carp among the dead. The fish will be taken to an area landfill.

"Cleanup efforts will begin Thursday morning and, depending on how that goes, may run into Friday and the weekend as well, said Solano. "They will have large cranes and barges that will scoop up the fish and they will put those into dump trucks to be disposed of."

The Illinois Department of Resources spent the day Wednesday trying to locate sport fish from the canal so they would not be harmed by the rotenone. The cost of the entire operation could be as much as $2 million.