The Great Lakes ecosystems remain under a significant threat from Asian carp. These unwelcome invaders can crowd out other fish species by outcompeting them for food resources. The carp have already overrun parts of the Illinois River, in some cases, accounting for more than 90% of the fish biomass. The presence of Asian carp in the Great Lakes could have devastating results for the region.
Between 2002 and 2011, the US Army Corps of Engineers (USACE) installed three electronic barriers in the Chicago Sanitary and Ship Canal near Romeoville to prevent the transfer of aquatic invasive species between the Great Lakes and Mississippi River basins. All information to date suggests the barriers are effective at preventing all but the smallest fish from passing upstream toward Lake Michigan.
For more than two years, the IDNR and US Fish and Wildlife Service have been monitoring the areas between the barrier and Lake Michigan, working with other federal, state and local partners (including the Forest Preserve District) to complete several intensive sampling efforts to catch and remove any Asian carp that may be present in the waterway. In over 20,000 hours of sampling, only one bighead carp has been captured upstream of the barrier, a fish caught in Lake Calumet by an IDNR contracted commercial fisher in June 2010.