It’s Time to Let Loose the Juice on Asian Carp Barrier

By JoshMogerman in News on Sep 10, 2011 8:00PM

The Army Corps of Engineers released a raft of new Asian carp reports yesterday as part of an ongoing campaign to keep the invasive species from accessing Lake Michigan where the fish could do serious damage to an already foundering ecosystem. Among the fish findings was a scientific vote of confidence for the DNA tracking tools that have shown the carp in Chicago’s waterways and an announcement that even though they are convinced the electric barrier installed to repel the fish is working, the Corps will be upping the amps…just to be sure. Bzzt!

The carp crisis has been fueled in large part by results from a cutting edge environmental DNA tool that detects the genetic marker of specific species in a waterway. It has been the source of some controversy since results began to consistently show Asian carp moving through Chicago. Proponents of quick action to keep the massive, munchers of Lake Michigan have pointed to the results as proof that more effort is needed. While many business voices had questioned the science behind the tool. The Corps’ new peer-reviewed report would seem to put those critiques to rest with its full-throated support of the technology.

Those eDNA results may have pushed the Corps to add zing to their zap in the waters of the Chicago Sanitary and Ship Canal. Laboratory testing and monitoring at the electric barrier near Romeoville has convinced the Corps that their fish fence is working. Nonetheless, they will up the voltage by 15% in October after determining that it would not generate sparks or otherwise ignite the barges loaded down with coal and oil which regularly float past. Despite the Corps’ assertion that all is well, not everyone is convinced---including, as noted in the Milwaukee Journal-Sentinel, the developer of the Corps-endorsed eDNA tests:

Some have speculated that the genetic material picked up in the water sampling came not from live fish, but perhaps from bilge discharges from barges, or from bird droppings or sewage discharges.

"There is not evidence those things happen frequently enough to be major explanations for the patterns (of DNA detection) we are seeing in the canals," said David Lodge, a biologist and Great Lakes expert at the University of Notre Dame.

Lodge and other scientists who pioneered the technology at Notre Dame say the DNA has been picked up in so many different areas of the canal system that the only plausible explanation is that Asian carp are indeed above the barrier.

Uh oh. The last batch of eDNA hits showed an Asian carp in the main branch of the Chicago River near the locks next to Navy Pier, which connects the river with Lake Michigan. That sort of news is likely to keep Great Lakes advocates on the warpath over this issue for the long haul advocating for something a bit more solid to keep the carp cooped up.