Populations of fish from the Chicago River show signs of recovery while 24 species reproduce

A research document written by a researcher from Shedd Aquarium and published in Journal of Great Lakes Research Evaluates the species of fish that appear in the Chicago river to maintain and support the resilient populations of biodiversity fish. Using light traps in 10 places in the Chicago river between the 1920s and 2022, more than 2,000 larval fish have been collected, and their DNA revealed 24 species of different fish present.

“This research represents the first documentation of the larvae of fish species occurring in the Chicago river, indicating that the recovery and catering efforts allow at least 24 species of Fleyer successfully and reaching the larval stage,” said Dr. Austin Happel, author of the study and the research biologist at Shedd Aquarium.

“Our previous studies have shown that improving water quality in the river increases biodiversity, and now we have more positive news because the populations proliferate locally in the river.”

The species that reproduce in the Chicago river include popular sports fish such as black crap, crap for arlequin and large mouth bar, and fodder fish such as gleeier alose, golden shiner and shiner spotfin. In addition, the study revealed Brook Silverside and Mimic Shiner larvae, which are generally considered to be intolerant to pollution, and therefore their presence was a pleasant surprise. The maximum abundance of larvae occurred in July, coinciding with temperatures reaching water in the 1970s (degrees Fahrenheit).

The study presented certain differences between sites that could suggest additional opportunities to increase Frai of fish habitats. More particularly, the species considered as intolerant of pollution were more common in the southern branch, but the more tolerant species to pollution were common in the northern branch of the Chicago river.

The discovery suggests that a combination of appropriate substrate, submerged vegetation and quality and water flow is probably present in the southern branch. In particular, there is a possibility of turmoil areas, such as unused borches in Bubbly Creek, which serve important nursery habitats and offer protection against predation and abundant foods. Happel’s current research focuses on how floating wetlands, which have been installed in the river by local non -profit urban rivers and the Shedd aquarium in recent years, affect the successful reproduction of fish.

“While people continue to worry and keep this critical freshwater ecosystem, we hope to see an increase in the number of fish reproducing in the system,” said Dr. Happel.

Overall, the study offers hope for other highly modified urban waterways and could provide information on the best way to support fish communities to be generated. In addition, it shows how restoration can work to bring wildlife back to local waters. This is important because healthy fish populations mean healthier aquatic environments, which ultimately benefits people who live and work around them.