ACRCC Monitoring and Rapid Response Update
June 29, 2012
This is the second set of 2012 eDNA samples that have been taken from Lake Calumet, part of the Chicago Area Waterway System (CAWS). Both sample sets have returned positive hits for silver carp DNA. A third set of samples was also collected from Lake Calumet on June 25, 2012. According to the ACRCC Monitoring and Rapid Response Workgroup (MRRWG) plan, if the third set of samples includes positive hits for either silver or bighead carp, the MRRWG will conduct Level 1 response including commercial fishing nets and electrofishing gear in this area.
The first round of eDNA sampling in 2012 was collected on May 22nd. Samples were collected from Lake Calumet and Little Calumet River. The monitoring results included 17 positives for silver carp (14 from Lake Calumet, 3 from Little Calumet River). Zero positives for bighead carp were found.
The ACRCC Monitoring and Rapid Response Plan (MRRP), developed by experts throughout the region, calls for a response action after three consecutive eDNA sample sets return positive hits from one location. However, as an extra precaution the Monitoring and Rapid Response Work Group organized a Level 1 rapid response for Lake Calumet that took place June 12th-13th. This response included three electrofishing boats and crews, as well as two contracted commercial netting crews, with Illinois Department of Natural Resources biologists on board, sampling for Asian carp in the area where the positive results were found. No silver or bighead carp were seen or captured during the monitoring effort.
At present, eDNA evidence cannot verify whether live Asian carp are present, whether the environmental DNA may have come from a dead fish, or whether water containing Asian carp DNA may have been transported from other sources, such as bilge water. U.S. Army Corps of Engineers is currently leading an interagency eDNA Calibration Study with U.S. Geological Survey and U.S. Fish and Wildlife Service to reduce the uncertainty surrounding eDNA results.