Live Asian carp discovered near Lake Michigan
TRAVERSE CITY, MI - A live Asian carp has been discovered in a Chicago waterway about nine miles from Lake Michigan - well beyond an electric barrier network designed to prevent the invasive fish that have infested the Mississippi River system from reaching the Great Lakes, officials said on June 23.
The silver carp was 28 inches long and weighed about 8 pounds, officials with the Asian Carp Regional Coordinating Committee said. It was caught on June 22 by a commercial fisherman under contract with the Illinois Department of Natural Resources about two miles below the below the T.J. O'Brien Lock and Dam in the Calumet River, on Chicago's south side.
The location is 34 miles closer to Lake Michigan than silver carp previously were known to have reached, said Charlie Wooley, Midwest deputy regional director for the U.S. Fish and Wildlife Service. Silver carp are among four types of Asian carp threatening to invade the lakes, where scientists say they could compete with native species, unravel aquatic food chains and devastate the region's $7 billion fishing industry.
Even so, officials cautioned the discovery doesn't mean Asian carp have become established in the rivers and canals between the barriers and the Great Lakes, or in the lakes themselves. It's more likely the carp was a loner that somehow made its way into the Chicago area, Wooley said.
"This is concerning but it's not a three-alarm fire right now and we don't expect it to be," he said in an interview.
The fish carcass is being sent to Southern Illinois University, where biologists will attempt to determine where it came from, said Kevin Irons, the state agency's aquatic nuisance program manager. They will examine its inner-ear bones for chemicals that are characteristic of particular waterways, he said.
They'll also determine its gender and, if female, study its ovaries for indications of spawning.
Under a plan developed by the multi-agency coordinating committee, the find triggers two weeks of "intense" searching for others. Crews will use nets and electric stunning devices to comb the area where the silver carp was found, plus other sections of the Chicago-area waterways and Lake Michigan's Calumet Harbor.
This is the second time a live Asian carp has been found beyond three electric barriers clustered in the Chicago Sanitary and Ship Canal 37 miles downstream from Lake Michigan. The other was a bighead carp caught in Chicago's Lake Calumet in 2010.
Bighead and silver carp are of special concern because of their voracious appetites for plankton - tiny plants and animals on which nearly all fish depend at some point in life. Silver carp are notorious for hurtling out of the water when startled, which can lead to bone-breaking collisions with people in motorboats.
The electric barrier system, operated by the U.S. Army Corps of Engineers, is intended to prevent fish from swimming between the Great Lakes and the Mississippi River watershed. Federal officials say it performs well, although a study has found that juvenile fish might get pulled through when caught in barge currents.
Members of Congress from some states in the Great Lakes region contend the electric barriers aren't enough. They want barriers in the Chicago-area waterways to separate the lakes from the Mississippi system, a step opposed by Illinois lawmakers who say it would disrupt shipping.
The Army Corps was scheduled to release an interim report in February on measures that could strengthen defenses against invasive fish at the Brandon Road Lock and Dam on the Des Plaines River in Joliet, Illinois, a choke point several miles downstream from the electric barriers. But the Trump administration has delayed making it public.
Lawmakers from Great Lakes states introduced bills this week that would order its release.
"The discovery of Asian Carp this close to Lake Michigan demonstrates how the window of opportunity to protect the Great Lakes is closing," said Rep. Bill Huizenga, a Michigan Republican.
The silver carp found this week was the first detected in the water past the barriers, Wooley said. Still, the main front for adult bighead and silver carp remains well downstream and is being thinned by continuous fishing, reducing the odds that enough will reach the lake to establish breeding populations, he said.
Environmental groups weren't satisfied.
"The lack of action by the administration is putting the Great Lakes at risk," said Molly Flanagan of the Alliance for the Great Lakes.