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Thousands Of Dead Fish Washing Up On Shores Of McKinley Park Lagoon

By Justin Breen | April 18, 2017 11:31am | Updated on April 21, 2017 10:47am
 Dead fish, perhaps numbering in the thousands, are in McKinley Park lagoon
Dead fish, perhaps numbering in the thousands, are in McKinley Park lagoon
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CHICAGO — Possibly thousands of dead fish — and countless others that are gasping for their last breaths — have piled up on the shores of McKinley Park Lagoon in the last two days.

And it may be due to the fact that the lagoon was drained last year after body parts, including a severed human head, was found there.

Samantha Hertel, vice president of the McKinley Park Advisory Council who is also an aquatic ecologist with a master's from Loyola University Chicago, said the park's lagoon has been filled with floating bluegill, catfish, largemouth bass and goldfish since Monday.

"It could be into the thousands," Hertel said of the amount of dead fish. "There are a lot of dead fish and a lot more at the surface trying to breathe."

Last year, the lagoon was drained after body parts were found there. A decapitated head was later identified.

Hertel said when the lagoon was drained, the fish remained in small pools of water, but phytoplankton — which helps keep the water oxygenated — were removed. The lack of oxygen in the water didn't affect the fish in the winter, when they aren't as active, but in recent warmer days the fish have been decimated.

Chicago Park District spokeswoman Jessica Maxey-Faulkner confirmed that draining the lagoon after the human head was found did have something to do with the die-off. 

"A fish kill over winter is normal, as the lagoon freeze a percentage of the fish die, a normal event every spring," Maxey-Faulkner said in a statement. "The issue is exacerbated at McKinley because of the low oxygen level in the water. The warm spring has made the fish more active than they would normally be at this time of the year, causing an increased demand on the oxygen in the water. ... The low level of oxygen is due to a low water level as a result of draining the lagoon in the late fall to assist the Chicago Police Department." 

Maxey-Faulkner added that the water was tested and no chemical issues were found, though the park district will continue to monitor the lagoon closely.

"In the short term we are turning the water on overnight to increase the water level, this will also help increase the oxygen level in the water," she said. "Once the issue is resolved the lagoon will be stocked for fish."