Wendella: Closing Chicago River would not keep out Asian carp

Overfish to manage levels, says Michael Borgstrom

(Above) A Chicago Water Taxi approaches the Wabash Avenue Bridge on the Chicago River last July.

10-Mar-10 – The president of Wendella Sightseeing Company, which has been operating tour boats and water taxis on the Chicago River for 75 years, says closing the Chicago Lock and Chicago River is “a bad idea,” and the way to fight Asian carp is to over-fish.

The U.S. Army Corps of Engineers is studying the impact closing the Chicago River to boat traffic would have. Asian carp have been found in the Illinois River, connecting the Mississippi River to Lake Michigan, and the Environmental Protection Agency believes the fish pose a “significant threat” to the Great Lakes eco-system.

Asian carp are large, prolific, and hungry. According to the EPA, they can be four feet long, weigh up to 100 pounds, and consume “vast” amounts of food. Researchers believe once the carp reached the Great Lakes, they would disrupt the food chain.

Catfish farmers, says the EPA, imported the carp in the 1970s to remove algae and other matter from ponds. When ponds overflowed during floods in the 1990s, the Asian carp made it to the Mississippi River and have been steadily swimming north.

(Left) The enemy. Photo obtained from U.S. Fish and Wildlife Service.

A possible recommendation from the U.S. Army Corp of Engineers is to close locks on Illinois waterways, including one near Navy Pier, as many as four days a week. That would affect tour boats and water taxis, hurting companies such as Wendella.

“Permanent, temporary or intermittent closure of the Chicago Lock will do nothing to prevent the migration of Asian carp into Lake Michigan,” says Michael Borgstrom, “especially since the Asian carp are more than 45 miles away.”

Borgstrom says he has been “deeply involved in this fight” for more than a month.

He fears closing the lock would allow biologists to search for the carp using electro-netting – temporarily stunning fish with a mild current – and by using rotenone, a chemical substance poisonous to fish.

“Rotenone poisoning,” he says, “would kill all aquatic life in the Chicago River, reversing the decades of work by Friends of the Chicago River and others.”

DNA testing of fish would not provide enough clues

Borgstrom (left) is critical of the Army Corps’s use of environmental DNA or “e-DNA” to test for Asian carp, calling it more of a “research project, not applied science.”

“e-DNA testing has indicated the presence of Asian carp…however it does not explain how the DNA got there or how long it has been present. In other words, e-DNA proves nothing.”

According to the web site Asian Carp Management, all fish, including Asian carp, release DNA into the environment. Filtering water samples, and then extracting and amplifying short fragments of the DNA that was shed can detect the presence of an individual species.

But e-DNA, says Borgstrom, as it is being applied. has not been peer-reviewed or independently vetted.

“In an attempt to verify the e-DNA results,” he explains, “the Illinois Department of Natural Resources has been fishing for Asian carp for more than two weeks. No Asian carp were caught and no live carp have been seen within 45 miles” of the Chicago Lock.

The answer, he believes, is over-fishing. “Closing the Chicago Lock and the Chicago River is a bad idea. If we want to stop the Asian carp, we need to fish them where we know they are, in the Illinois River.”

By over-fishing, it is believed the number of Asian carp could be reduced to an acceptable level.

“Fishermen have overfished entire species in the Atlantic and the Pacific. In fact, Asian carp have been overfished in China. I am certain that with a coordinated effort, Asian carp can be eradicated from the area while providing needed jobs and new industries.”

Recommendations from the U.S. Army Corp of Engineers are expected by April 1.