Environmental DNA (eDNA) is a process used by the Asian Carp Regional Coordinating Committee in which genetic material (cells containing DNA from tissue, mucus, feces and/or urine) is extracted from water samples to help inform decisions related to preventing Asian carp transfer. eDNA evidence complements intensive use of traditional monitoring and suppression tools. At present, eDNA evidence cannot verify whether live Asian carp are present, whether the 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, storm sewers or fish-eating birds.
USACE began using eDNA in cooperation with the University of Notre Dame (UND) in August 2009. UND collected and analyzed samples for the presence of bighead and silver carp DNA throughout the Chicago Area Waterway System (CAWS) until June 2010.
Following a transition plan and two-year partnership, lead for the eDNA surveillance program seamlessly transitioned from the U.S. Army Corps of Engineers, Engineering and Research Development Center, Center for eDNA Application and Research, to the U.S. Fish and Wildlife Service's new Whitney Genetics Lab in Onalaska, Wisc. in spring 2013.
The eDNA sampling season generally runs from May to October. eDNA results can now be found online at http://www.fws.gov/midwest/fisheries/eDNA.html. Archived USACE-sampling results are below.
USACE is leading a three-year Asian Carp eDNA Calibration Study (ECALS) with the U.S. Geological Survey and USFWS to reduce the uncertainty surrounding eDNA results. ECALS investigates alternative sources and pathways for eDNA detections beyond a live fish. The study also examines how environmental variables such as light, temperature and water velocity impact eDNA detections; explores the correlation between the number of positive samples and the strength of the DNA source; develops more efficient eDNA markers to cut the sampling processing time in half and models eDNA transport specific to the CAWS.
The results of ECALS will allow for more context for interpretation of eDNA results and investigate ways to make the eDNA sampling process more efficient through decreased processing time and reduced costs. In the CAWS, when results indicate positive detections for Asian carp eDNA, yet hundreds of hours of netting and electrofishing turn up no actual fish, we have the ecological and fiscal responsibility and duty to determine what the sources beyond a live fish could potentially be. We want to arm scientists with the best monitoring tools possible.
ECALS has indicated that other sources of DNA beyond a live fish include fishing gear and barges that travel from areas with high numbers of Asian carp. Bird-tagging studies show that some carp-eating birds can travel 800 miles, which may lead to positive detection of Asian carp eDNA from bird feces.
For more information on ECALS, visit: http://www.asiancarp.us/ecals.htm.
Archived 2012 USACE eDNA sampling results:
7 November 2012 - eDNA Surveillance Status Map
Samples were collected from Lake Calumet and the Little Calumet River by the Illinois Department of Natural Resources on Oct. 22.
There were 29/38 positives for silver carp and 4/38 positives for bighead carp in Lake Calumet. Note that these are the first positives for bighead carp at any location this year.
There were 5/48 positives for the Little Calumet River, all silver carp.
This represents the last eDNA sampling event for the 2012 season.
Previous 2012 eDNA results
25 October 2012: North Shore Channel: 8 positives for silver carp
23 October 2012: North Shore Channel: 8 positives for silver carp; Chicago River: 7 positive for silver carp
16 October: Lake Calumet: 11 positives for silver carp; Little Calumet River: 5 positives for silver carp
9 October: North Shore Channel: 13 positivies for silver carp; Chicago River: 17 positives for silver carp
21 September: Lake Calumet and Little Calumet River: 8 positives for silver carp; Zero positives for bighead carp
6 August: Chicago River: Zero positives for silver carp; Zero positives for bighead carp
24 July: Lake Calumet: 3 positives for silver carp; Zero positives for bighead carp
11 July: Lake Calumet: 2 positives for silver carp; Zero for bighead carp (sampled prior to the 11-13 July response event)
10 July: North Shore Channel: 3 positives for silver carp; Zero for bighead carp
Chicago River: 6 positives for silver carp; Zero for bighead carp
25 June: Lake Calumet: 7 positives for silver carp; Zero positives for bighead carp
Little Calumet River: Zero positives for silver carp; Zero positives for bighead carp
11 June: North Shore Channel: 1 positive for silver carp; Zero positives for bighead carp
Lake Calumet: 3 positives for silver carp; Zero positives for bighead carp (sampled prior to 12-13 June response event)
22 May: Lake Calumet: 14 positives for silver carp; Zero positives for bighead carp
Little Calumet River: 3 positives for silver carp; Zero positives for bighead carp
No bighead or silver carp observed or captured above the barrier in 2012.
The Monitoring and Rapid Response Workgroup (MRRWG) will continue to collect data for analysis to help guide future actions and inform the Asian Carp Regional Coordinating Committee as to its findings on a routine basis. For ongoing, detailed Asian carp sampling results, please visit asiancarp.us.
Click to enlarge: