(WBBM NEWSRADIO) — New research shows that while invasive carp are spreading through the Midwest, the fish mostly prefer to stay out of Chicago.
The study, published in Scientific Reports, made two key findings: Invasive silver carp have not advanced beyond a particular stretch of the Illinois River, and the species also appears to change its behavior when introduced to the Chicago-area water.
Cory Suski, a professor of natural resources and environmental sciences at the University of Illinois and a co-author of the study, said the fish instantly slow down as they move closer to the Chicago area. He believes contaminants in the water play a factor.
“This is kind of a stress response,” he said. “It’s a response to, sort of, something uncomfortable in the environment for them. They don’t really know exactly what’s going on, but they’re just going to stop and wait it out and hope that that negative stimulus goes away.”
Suski said it’s unclear whether contaminants or some sort of compound present in Chicago-area water are to blame.