Army Corps Posts New Positive eDNA Results for Asian Carp Near Lake Michigan
Posted July 20, 2011 in Curbing Pollution, Saving Wildlife and Wild Places
Today I discovered that the Army Corps this week posted on its web site new environmental DNA (or “eDNA”) test results detecting the presence of Asian carp near Lake Michigan. The results reported are from eDNA tests done this summer, between May 10, 2011, and June 27, 2011. There appear to be at least 9 positive results reported, many of which are clustered near Lake Calumet, where a live Asian carp was captured last summer.
These new eDNA results were apparently posted without any public announcement. I’m not surprised, as the Army Corps has been telling everyone for months that “there has been no evidence” that its electric barrier has not worked perfectly to keep Asian carp from invading Lake Michigan. The Army Corps can only get away with saying that by ignoring the eDNA evidence, which clearly shows that at least some Asian carp have made it past the electric barriers in the CAWS and have a free path into Lake Michigan.
As my colleague Josh Mogerman pointed out yesterday in the Detroit Free Press:
"We don't know how much time we have," he said. "We need to stop dragging our heels."
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Comments
Tom Matych — Jul 21 2011 06:12 AM
The barrier wont stop anything, We have native predators for juvenile Asian Carp. I suggest we start restoring them before Asian carp become dominate and have the upper hand.
Thamus — Jul 21 2011 06:59 PM
Do we know exactly where the eDNA is coming from? I have said for years that I have seen DEAD silver carp on the sides of vessels through AND ABOVE O'Brien lock. Where do those dead silver carp end up when they are swept off the decks? Also, fish get caught and die in the couplings of barges... I have seen that too. I have been telling people and that powers be for years now what I see. Back in 2009 when they first receieved positve eDNA hits I can confirm on a number of occasions dead fish being transported unwittingly. Surely, now with the lower MS open after floods... More and more cargo is making its way up from the deep south and southern Illinois... Surely some dead fis are slipping by and falling into the water... Especially in fleeting areas like Lake Calumet. Why are the eDNA hits ONLY in the fleeting areas? Do the fish only swim with boats.
Can we really trust the eDNA? This seems to be very shaky science.
Thamus — Jul 21 2011 07:38 PM
To clarify what I am saying and have seen with my own eyes going back to the late summer of 2009... Right before all this hit the fan... Is that there could be a few/couple of tow boats pushing barges that are responsible for depositing a dead fish into the water... And if the debris is in the couplings... Nobody will ever know! Look at the Corps map for Lake Cal... The findings are in direct correlation to how the river flows. I need clarrification... Can one rotting fish on shore be dropping bits and pieces off (scales and what not) into the water?... Thus sending what appears to be "swimming fish." Why no positive hits at other times when the southern boats weren't making its way up north?... Now wham... As soon as the southern cargo can get up north... There are positive hits. It is summertime, this is a busy time for boats heading north.
Thom Cmar — Jul 25 2011 11:38 AM
Thamus: your comments fail to mention that using eDNA to detect the presence of Asian carp has now been covered in two peer-reviewed publications. Your personal opinion about the science aside, the scientific community has accepted the Lodge team's methodology as sound.
Also, re: your theory about barges being the source of Asian carp DNA, how do you explain that there have been positive eDNA results in portions of the waterway system, such as the North Shore Channel, where barges do not typically go? The eDNA detections have not been limited to areas where barges frequent.
Thamus — Jul 25 2011 06:48 PM
Good points Thom. About the North Shore Channel... Detections have, like you said, been past the end of commercial navigation on the NSC... YET... The North Shore Channel is a stones throw from some of the inland lagoons that have Asian carp in them. Maybe... All this of course leads to the MWRD possibly sending "tainted" water around.
Of course there can be other ways the eDNA can get there withOUT actual swimming fish. The number one reason is barge traffic which I can testify that I have seen with my own eyes. Any coincidence these hits are coming at almost the same time they did in 2009? The hits are almost entirely following the shipping patterns. Of course so. I know for a fact that there was dead silver carp in the water back before the testing started in 2009. I also know for a fact that dead silver carp are still being kicked into the water now from shipping interests that aren't as careful.
Why do the positive hits seem to skip a whole section of the middle CAW's and then end up at the heads of navigation? Let's see what other times of the year bring with regard to positve eDNA hits.
Take a look at the map. I agree the North Shore Channel is vexing... Yet, it can still be navigation thing too... It isn't too far from the end of commercial navigation where debris and dead material can drift.
Thamus — Jul 25 2011 08:11 PM
Thanks again Thom for letting me comment in a sincere and truthful manner. I want to make it clear that I am not calling into question the actual process of the eDNA... That is not where the science is shaky. I have total faith in the peer review and that the actual eDNA from the carp is true and accurate.
I do dispute where the detections are coming from. Without finding actual swimming fish, we can't prove that this is where the eDNA is coming from (swimming fish). Now, just like back in 2009... Most positive hits are coming from silver carp. Strange coincidence that if the silver are "popping like corn" in Peoria, they will get caught in the couplings where they have been "ground up to a pulp." Now, if that material is above the waterline, the next area where they uncouple and get deposited into the water will be in port... Possibly Lake Calumet, the Chicago river at the junction AND around the end of navigation at the NSC. Again, it is mostly SILVER that they are finding as they did in the past. Also factor in the summer shipping push north, warmer/lower water down south (more fish jump), and inattentive shipping interests.
Thom... I am not calling Mr. Lodge out. I have complete faith in the eDNA technology. I am stating reasonable facts why these eDNA detections MAY NOT be swimming fish. We haven't found a swimming fish outside of one bighead. Bighead is not what is being mostly detected. And... Don't tell me we are hunting for one or maybe a few fish... That sounds unreasonable and is not an indictment of how well the electric barrier may or may not be working.