The Chicago River's fish populations have lived through a multitude of conditions. Pre-European settlement, fishes flourished in the slow-moving prairie stream. As humans began to modify the river in the 1800s and 1900s, fish species were often negatively impacted. Pollution and lack of habitat led to declines in fish populations, so that by the 1970s, there were fewer than 10 species of fish that lived in the river.
Happily, fish numbers have rebounded since those tumultuous times. Improvements in water quality and increasing habitat mean that more fish are returning to the Chicago River system. Today, there are more than 70 species of fish in the river! As Friends and other organizations continue to advocate for a cleaner river and engage in restoration projects, we expect fish numbers to continue to rise.
What about Asian carp?
Bighead and silver carp, commonly grouped together as "Asian carp," are introduced species that have invaded much of the Mississippi River basin. The carp are currently NOT in the Chicago River system. Click here and here for more information on aquatic nuisance species.
Friends' fish projects
Click the links below for more information on our fish projects:
List of Chicago River fishes
Click here to view a list of 70 species of Chicago River fishes.
Check out some of highlighted fishes below (click each fish for more information).
Bluegill (Lepomis macrochirus)
Channel catfish (Ictalurus punctatus)
Common carp (Cyprinus carpio)
Largemouth bass (Micropterus salmoides)
Pumpkinseed sunfish (Lepomis gibbosus)