Juvenile silver carp 80 miles from Lake Michigan

Multiple agencies confirmed the discovery of several hundred juvenile silver carp, measuring about 4 to 6 inches, in the Marseilles Pool of the Illinois River roughly 80 miles from Lake Michigan—the farthest upriver that small carp have been found in the 16-year monitoring effort. Officials say the size and location suggest a spawning event may have occurred further upriver or in tributaries feeding the Illinois River, prompting enhanced surveillance and expanded electrofishing in the upper river and its backwaters. Authorities plan to ramp up monitoring and study the fish’s origin through microchemistry analysis, while increasing monitoring in the Dresden Island Pool as a precaution. Commercial fishing for adult carp is expected to resume in September in the Starved Rock, Marseilles, and Dresden Island Pools, once conditions are suitable, aiding removal efforts. The discoveries come amid a pause and administrative review of the Brandon Road Interbasin Project, a set of barriers intended to block carp migration toward Lake Michigan, a move criticized by Gov. JB Pritzker and tied to concerns about federal funding under current President Donald Trump. Flood conditions and warm water this summer are cited as contributing factors to the potential spawning event and expanded carp activity.