UNDATED (Det. Free Press) - Great Lakes advocates said today they've been told that DNA evidence of one species of Asian carp has been detected above the electric barrier intended to keep the fish out of Lake Michigan.
The DNA was detected in a channel that splits off the Chicago Sanitary and Ship Canal below Chicago, and leads to Lake Michigan, known as the Cal-Sag channel.
"That is what we understand," said Jennifer Nalbone, director of Great Lakes United's campaign against invasive species.
Previously, DNA of Asian carp has been found a mile below the barrier. Last week, the Corps and Illinois Department of Natural Resources said they planned to poison nearly six miles of the ship canal in early December to kill any possible carp so they would not be able to breach the main barrier when it goes down for maintenance for a few days.
On November 17, the University of Notre Dame notified the U.S. Army Corps of Engineers that some water samples, taken from the area between the electric barriers and Lake Michigan on September 23 and October 1, tested positive for the presence of Asian Carp. The positive samples were from an area about one mile south of the O'Brien Lock, approximately 8 miles from Lake Michigan.
Asian carp have taken over the Mississippi and other nearby rivers and can grow to huge sizes. Because they are voracious feeders and breeders, they are expected to out-compete native fish once they reach the Great Lakes. The Army Corps has built two electric barriers, one experimental and the other permanent, to try to keep them out, but in the past three months, new DNA tests have shown evidence of the carp much nearer to the barrier than scientists had thought.
Nalbone said she's waiting to hear what the Corps has to say, but that various environmental groups would likely call for an immediate closure of the locks on the ship canal.
Barge operators are already upset about the loss of business from the multiday shutdown scheduled for early December. Barges bring oil, coal, cement and other crucial goods through the canal.
BY TINA LAM, FREE PRESS STAFF WRITER
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