(AP) -- Armed with sprawling fishing nets and boats equipped with electric prods, state and federal fisheries biologists began a "search-and-destroy" mission in Chicago-area waterways Wednesday aimed at rooting out the dreaded Asian carp.
The operation began as officials met in Michigan to address the federal government's plans and recommendations for protecting the Great Lakes from the invasive fish.
Twenty commercial fishermen and biologists from the Illinois Department of Natural Resources and the U.S. Fish and Wildlife Service are braving frigid temperatures to search Chicago-area waters for silver or bighead Asian carp that have breached electric fish barriers.
"It's dangerous, and we appreciate all of their efforts and their professionalism in order to combat Asian carp and to do the search-and-destroy effort we're doing today," said Marc Miller, Illinois' natural resources director.
Crews are focusing on areas where warm water from industrial operations, including power plants and wastewater treatment plants, enters the waterways. Fish tend to congregate near the warmer water in the winter.
During one search operation at a suburban Chicago canal, steam rose from the water as crews set out a large mesh net, then circled its perimeter, sending electric charges into the water to herd fish toward the net.
While the search yielded plenty of fish, including a substantial-looking regular carp, no Asian carp were found. The search is to continue for two to three weeks.
Officials have environmental DNA evidence from several locations suggesting the destructive species has gone past the electric barriers, but no Asian carp have been found beyond them.
"We presume they would be present anywhere within this waterway system," said John Rogner, assistant director of the Illinois natural resources department.
In December, wildlife officials discovered a single Asian carp in an Illinois canal leading to Lake Michigan, the nearest the species has come to the Great Lakes. Environmentalists fear if the carp reach the lakes they could starve out native fish species and devastate a $7 billion-a-year fishing industry. Carp can grow to 4 feet in length and 100 pounds.
Michigan has asked the U.S. Supreme Court to order Chicago-area shipping locks closed to keep carp out, a request supported by Minnesota, Wisconsin, Ohio, Pennsylvania and New York. Illinois opposes the closure. An Obama administration proposal on controlling carp also rejects closing the locks.
Meanwhile Wednesday, officials were to meet in Ypsilanti, Mich., to discuss the federal response to the Asian carp threat to the Great Lakes. The event is the second of its kind in the region.
The meeting will include discussions among scientific experts and representatives from the U.S. Environmental Protection Agency, U.S. Fish and Wildlife Service, Army Corps of Engineers, Coast Guard, Great Lakes states and the White House Council on Environmental Quality.
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More information: Asian carp management: http://www.asiancarp.org/regionalcoordination