The Asian Carp Regional Coordinating Committee (ACRCC) recently announced that intensive monitoring actions would be implemented in the North Shore Channel of the Chicago River after three consecutive rounds of Environmental DNA (eDNA) sampling yielded positive results for Asian carp DNA in the North Shore Channel.
The ACCRC’s 2012 Monitoring and Rapid Response Plan calls for a Level 1 response to three consecutive rounds of positive eDNA results in one area. As an extra precaution, the ACRCC also will conduct intensive monitoring in a six-mile stretch of the Chicago River beginning near the Chicago lock, after one set of samples tested positive for eDNA in that area.
While the North Shore Channel is regularly monitored for the presence of Asian carp, the level 1 response intensifies efforts with additional commercial fishing crews, agency electrofishing boats, and additional deep water sampling gear during an intensive four-day fishing period.
Biologists from the Illinois Department of Natural Resources, the U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers planned to be on the water with contracted commercial fishermen beginning Tuesday October 16th through Friday, October 19th.
During sampling, crews lay various net types throughout the North Shore Channel and in channel areas of the Chicago River. Agency electrofishing boats sample fish in shoreline areas and drive fish towards the nets. Gears are attended at all times and commercial and private vessel traffic are be able to proceed with minimal interference.
A notice to mariners is broadcast by the U.S. Coast Guard to further inform any water traffic during the effort, and daily updates will be posted on the ACRCC website (http://asiancarp.us).
Three separate eDNA samples sets were taken at the North Shore Channel between June 11th and September 11th, revealing 17 positives for silver carp DNA out of 171 samples. Full eDNA sampling details can be found at the U.S. Army Corps of Engineers website: (http://www.lrc.usace.army.mil/Missions/CivilWorksProjects/ANSPortal/eDNA.aspx).
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.
The U.S. Army Corps of Engineers is leading an Asian Carp eDNA Calibration Study (ECALS) with the U.S. Geological Survey and the U.S. Fish and Wildlife Service to reduce the uncertainty surrounding eDNA results and investigate alternative sources and pathways for eDNA detections beyond a live fish.
Since 2011, the ACRCC has been conducting intensive bi-monthly monitoring in the Chicago Area Waterway System, including in the North Shore Channel, using agency electrofishing and contracted commercial fishers. From March 2011 through September 2012, crews from MRRWG action agencies spent over 6,500 person-hours sampling with conventional gears in the CAWS upstream of the electric barrier.
Crews completed over 400 hours of electrofishing and 130 miles of net and caught nearly 140,000 fish representing over 60 species. No bighead or silver carp were captured or observed upstream of the electric barrier during this time.
The ACRCC is following a set of protocols in the 2012 Monitoring and Rapid Response Plan (MRRP) which outline specific circumstances that would trigger one of three different response levels.
For more information, visit: www.asiancarp.us
source: U.S. Geological Survey