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Asian Carp, Invasive Species, Swims Nearer Lake Michigan

The Asian Carp may have gotten past this barrier, giving it a clear path to Lake Michigan. Frank Polich/AP Photo hide caption

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Frank Polich/AP Photo

The Asian Carp may have gotten past this barrier, giving it a clear path to Lake Michigan.

Frank Polich/AP Photo

People who love to fish the waters of the Great Lakes for salmon, trout and sturgeon have reason to worry today.

Federal officials are reporting that the Asian carp may have gotten past a electric barrier meant to prevent the invasive species from entering the Lake Michigan and the other Great Lakes where they could threaten the existence of the multi-billion dollar sports fishing business.

According to the Associated Press:

Officials with the Army Corps of Engineer say Friday that DNA of the giant carp have been found north of the barrier in the Chicago Sanitary and Ship Canal.

A bighead carp at Chicago's Shedd Aquarium. M. Spencer Green/AP Photo hide caption

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M. Spencer Green/AP Photo

If correct, that would mean the carp might reach Lake Michigan if they get through a navigational lock. From there, they could spread throughout the Great Lakes and out-compete native species for food


The Fish and Wildlife Service provides useful background on the Asian carp. For instance, there are several species of these fish — the Bighead, Black, Grass and Silver carps.

These fish can get huge. The Black and Grass carps can grow to more than four feet and weigh in at more than 100 pounds.

The FWS further explains why the fish are such bad news.

... carp have been imported into the U.S. for use in the aquaculture industry. There are concerns about the effects that four Asian carp species (grass, bighead, silver, and black) are having on native fish and shellfish when released or escaped into the wild.

The carp grow to large sizes (50-110 lbs.) and quickly become some of the most abundant fish captured from an area, possibly out competing native species for food or habitat resources. They have become so abundant in the Missouri River that there have been reports of commercial fishermen abandoning fishing sites due to the large catch of Asian carp. The carp are found throughout the Mississippi River drainage. They have not been found in the Great Lakes, and there is some concern that they may spread to that area through the Illinois River and Chicago Shipping and Sanitary Canal.

Illinois officials announced earlier this month, that they planned to dump fish poison into the Chicago Sanitary and Ship Canal to kill carp below the barrier. The plan is to use electrical prods to chase good fish to the surface so they can be relocated away from the poison.

Asian carp have been detected using environmental DNA testing in the canal below the barrier, and there is consensus among federal, state, and local agencies along with other partners that actions must be taken to prevent these invasive species from reaching Lake Michigan while Barrier IIA is shut down.

The Illinois Department of Natural Resources (IDNR), in coordination with the multi-agency Asian Carp Rapid Response Workgroup along with the Great Lakes Interagency Task Force, will manage the application of rotenone in the CSSC. While the toxicant will eradicate Asian carp and other fish in the canal, rotenone does not present a risk to people or other wildlife when used properly.

The application of rotenone is planned for December 3, and crews from the IDNR and other agencies will remove fish from the canal and dispose of them in a landfill. The fish habitat in the section of the canal scheduled for treatment is made up of mostly non-sport fish with the most common species being common carp, goldfish, and gizzard shad. Before the application of rotenone, an electro-fishing operation will be conducted to relocate as many sport fish as possible. Rotenone dissipates quickly on its own, but to accelerate that process a neutralizing agent known as potassium permanganate will be used following the application.

NPR's David Schaeper, who on Friday reported on the latest Asian carp developments for the network and has covered this story for some time, told me after listening to a Friday conference call with officials:

... While they can't say definitively they are no Asian carp is Lake Michigan, the state and federal officials and scientists all say they have no evidence whatsoever that Asian carp are in the lake.


...The new DNA evidence puts the ugly fish about 6 — 8 miles away, near the Thomas O'Brien Lock on the Calumet River, but that is 20 miles closer to the lake than previously thought.

David also tells me:

Environmental and conservation groups are calling for the three locks between Lake Michigan and the Chicago and Calumet Rivers to be closed in a last ditch effort to keep the Asian carp from invading the Great Lakes.

From their press release:

The groups demand that the U.S. Army Corps of Engineers and state of Illinois close the O'Brien, Chicago River and Wilmette locks until monitoring results show the waterways are completely clear of bighead and silver carp and that an electric barrier built to keep them out of Lake Michigan and the other Great Lakes has not been breached.

"Today, there are no second chances," said Joel Brammeier, acting president of the Alliance for the Great Lakes. "We cannot miss this opportunity to protect the lakes from these fish and their devastating legacy. It's imperative we put the health of the Great Lakes — the world's largest surface freshwater system — first."

David also tipped me to YouTube videos showing the Asian carp's propensity to jump out of the water when startled.

Over the years, David has had stories about the invasive species problem in the Great Lakes, including the Asian carp; the hope scientists placed in electricity to stop the carp, and the notion that Americans might as well make a virtue of necessity by learning to eat the carp.