CHICAGO (CBS) — Hundreds, and probably thousands, of dead fish have been floating at the top of the lagoon in McKinley Park at 37th and Damen.

“Around the entire lagoon you can see there are dead fish and a lot of living fish that are up at the surface trying to breathe,” said Samantha Hertel, vice president of the McKinley Park Advisory Council, who just finished her master’s in aquatic ecology.

The lagoon was mostly drained last fall – after a severed human head was found there.

“They left plenty of water for the fish, but the algae population, the phytoplankton that produces oxygen – that went right down the drain with the water,” Hertel said.

And she saif the fish were all right during the winter, partially because their metabolic rate is lower.

fish 1 Hundreds Of Dead Fish Found Floating In McKinley Park Lagoon

Park district officials clean up the McKinley Park Lagoon after hundreds of fish were found floating (WBBM/Steve Miller)

But not now…

The fish getting hit the hardest are the bluegills, Hertel said, and the larger catfish.

fish 4 Hundreds Of Dead Fish Found Floating In McKinley Park Lagoon

Samantha Hertel, vice president of the McKinley Park Advisory Council examines the lagoon to find floating fish and living fish near the top, looking for air (WBBM/Steve Miller)

“It’s unfortunate to see, but long term, they will be fine. They do restock the fish. So the population will be fine.”

But for now, a lot of fish are floating and crayfish are trying to crawl out for air.

Chicago Park District released a statement on the issue:

“In response to the hundreds of dead fish in the McKinley lagoon, a fish kill over winter is normal, as the lagoon freeze a percentage of the fish die, a normal event every spring. 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. The Chicago Park District issued further water testing to confirm that there aren’t any chemical issues in the water and will continue to monitor the water closely through the spring season. 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.

Once the issue is resolved the lagoon will be stocked for fish.”

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