Carp DNA found closer to the lake
Written by Milwaukee Journal Sentinel   
Tuesday, 12 January 2010 10:05
New samples from waterway north of downtown Chicago turn out positive.

Environmental DNA samples taken in recent weeks reveal that Asian carp apparently have infested another waterway just below the shores of Lake Michigan, this time north of downtown Chicago, the Journal Sentinel has learned.

U.S. Solicitor General Elena Kagan made reference to some "initial indications" of more waters infested with the jumbo-sized fish in a Jan. 6 memorandum to the U.S. Supreme Court. Kagan is opposing the State of Michigan's request for a Supreme Court injunction to close some navigation locks to keep the invasive fish from spilling into Lake Michigan.

To date, no actual Asian carp have been found above an electric barrier on the Chicago Sanitary and Ship Canal, about 20 miles south of the shores of Lake Michigan. But in November, the Army Corps of Engineers acknowledged that water samples tested positive for Asian carp "environmental" DNA above the barrier.

Those samples, taken by a team of University of Notre Dame researchers, indicated the fish are about six miles from the shore of Lake Michigan on the Calumet River south of downtown Chicago, just below the O'Brien lock.
Now a fresh batch of tests reveals that the carp have made their way up the northern branch of the Chicago River north of Chicago. That river has a direct connection to Lake Michigan via a "sluice gate" and pumps operated by the Metropolitan Water Reclamation District of Greater Chicago.

That system sucks Lake Michigan water into the North Shore Channel, which flows into the Chicago River, and it is one of the structures the state of Michigan - backed by Wisconsin, Ohio, New York and Minnesota - wants to close. The system also acts as a safety valve in big rains, sending floodwater backward through the gate and into Lake Michigan.

"On Dec. 31, 2009, the Corps learned that the University of Notre Dame laboratory has initial indications of two positive eDNA results for Asian carp in a new area, specifically silver carp near the Wilmette pumping station," states Kagan's memo.

The filing said the Army Corps was expecting a report confirming the finding by Jan. 7. That report has arrived at Corps offices, and it shows the carp have made the advance north of downtown.

"They did get a report," Army Corps spokeswoman Lynne Whelan said late Monday. "Yes, it did confirm a small number of samples positive for silver carp."

Whelan could not say specifically where the new samples were taken, and efforts to reach Notre Dame biologist David Lodge for comment were unsuccessful.

The state of Illinois, the Army Corps and the water reclamation district are co-defendants in the Supreme Court case, which has been ongoing since the 1920s after Chicago's reversal of its namesake river to flush its sewage down the Sanitary and Ship Canal.

In its filing opposing Michigan's request to close the locks, Illinois called Lodge's environmental DNA testing "nascent technology" and noted that the science behind it has yet to be peer reviewed or published.
It is opposing closure of the locks and the sluice gate because of the impact it would have on the barge industry and the need to open the locks and gate during heavy rains to prevent widespread flooding in the Chicago area.

Lodge, however, said last week he has thoroughly shared the science behind his work with the Army Corps and others, and the Environmental Protection Agency has stated it has a "high degree of confidence" in using his research for management decisions.

The Supreme Court may decide whether to consider the case at a conference Friday, though nothing has been announced officially. Meanwhile, Illinois Sen. Dick Durbin is planning to host a meeting Tuesday morning at Chicago's Shedd Aquarium for officials from the Army Corps and the EPA, among others, to talk about what steps the federal government intends to take to keep the fish from invading the Great Lakes.

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