According to new research, the Chicago River has become significantly cleaner and healthier in recent decades. Photo Credit: Shedd Aquarium
Animals USAFish Are Swimming Their Way Back to This River
A new study reveals that the Chicago River is once again nurturing life: dozens of fish species are now successfully reproducing, indicating a significant recovery in water quality and ecosystem health.
“As people continue to care about and conserve this critical freshwater ecosystem, we hope to see increases in the number of fish spawning in the system,” says Austin Happel of Shedd Aquarium.
Between 2020 and 2022, scientists deployed light traps at 10 sites along the North and South branches of the river, collecting a total of 2,211 fish larvae. Laboratory DNA testing revealed 24 different spawning species, including brook silverside and mimic shiner, species usually intolerant of pollution. These findings contribute to the known diversity (nearly 60 species live in the river) and indicate that it can now support the full life cycle of many fish. With ongoing investment in habitat restoration and water quality improvements, the Chicago River is proving that ecological renewal isn’t just possible, it’s already underway.
