New research in Illinois utilizing listening devices aims to understand how fish interact in Chicago River

How far do largemouth bass swim? How do bluegills respond to poor water quality? And where do common carp, sunfish, and crappies go in the winter months?
One might be able to answer these questions simply by listening to “sound fish make.” At least that’s how researchers from Shedd Aquarium are approaching a new study of the Chicago River, where 80 fish were outfitted with tags that bounce off of 32 receivers – or listening devices – that continuously listen for unique sound signals from those tags, which emit a unique frequency linked to each individual fish.