No Silver or Bighead Carps Found as Sampling Concludes in Illinois Waterway

Katie Steiger-Meister
Tim Schweizer
No Silver or Bighead Carps Found as Sampling Concludes in Illinois Waterway
CHICAGO, IL – No silver or bighead Asian carp were seen or caught during two-weeks of intensive monitoring initiated by the capture of an adult male silver carp 9 miles from Lake Michigan on June 22. The silver carp was captured by a contracted commercial fisher below the T.J. O’Brien Lock and Dam. The capture triggered the Asian Carp Regional Coordinating Committee’s Contingency Response Plan. Contingency response becomes necessary when silver or bighead carps are discovered in unexpected places in the Chicago Area Waterway System. With the conclusion of the intensive monitoring event on July 7, barrier defense, removal and monitoring actions will continue to be guided by the 2017 Monitoring and Response Plan. The plan includes two-weeks of additional intensive Asian carp monitoring in the waterway upstream of the electric dispersal barriers in September.

Crews from the U.S. Fish and Wildlife Service (USFWS), U.S. Army Corps of Engineers (USACE), Illinois Department of Natural Resources (IDNR), Illinois Natural History Survey and contracted commercial fishers conducted the monitoring operation. The U.S. Coast Guard provided notice to mariners of increased activity in the areas above and below the T.J. O’Brien Lock and Dam. The field portion of the operation exceeded 1,950 person-hours. In addition, commercial fishers working with IDNR biologists set more than 43 miles of gill net, while crews with IDNR, USACE and USFWS conducted 365 electro-fishing runs for a total of more than 91 hours of effort.

Four electrofishing crews, three contracted commercial fishers, and a specially outfitted netting boat were deployed daily below the T.J. O’Brien Lock and Dam, in Lake Calumet, and in an area from the T.J. O’Brien Lock and Dam to Calumet Harbor. The operation covered a 13-mile section of the waterway and Calumet Harbor with intensive monitoring.

Preceding the sampling efforts that resulted in the capture of a silver carp in late June, biologists collected environmental DNA (eDNA) samples at four sites above the electric dispersal barriers in the Chicago Area Waterway System. None of the 240 samples, collected the week of June 5, were positive for the presence of genetic material from either bighead or silver carps.

The silver carp captured June 22 was sent to Southern Illinois University for analysis to determine the fish’s age and origin. More information will be shared as it becomes available.

The Asian Carp Regional Coordinating Committee is a consortium of provincial, federal, state and local partners united in their efforts to prevent the spread and establishment of Asian carp in the Great Lakes. For more information, please visit Downloadable images of the contingency response are available at
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