Ingham Lake fish kill puzzles residents
Reporters note: We will have an update, including an interview with Mike Hawkins of Iowa DNR fisheries, in Thursday’s edition of the Estherville News.
Several possible explanations for bushels of dead fish on lake shore
By Amy H. Peterson
Late last week, hundreds of carp and crappie began drifting to the south shore of Ingham Lake outside Wallingford, buoyed by strong winds from the north. Along the shore on 230th Street, a conglomerate of fish corpses crowded the shoreline with more drifting from farther out in the lake.
Area residents reported an aerator had been turned off at Ingham Lake over the winter, a possible explanation for the dead fish.
The Iowa Department of Natural Resources, the entity that handles aerators and other interventions on Iowa’s lakes, said, “Fish kills have become a focus of public attention as more interest is being place on the quality and condition of Iowa’s [bodies of water].”
With two feet of snow sitting on top of possibly 24 inches of ice under the snow, sunlight is blocked from reaching aquatic plants, preventing them from producing oxygen in the lake. The lack of oxygen could cause fatal hypoxia in the fish.
In the interest of letting nature take its course without excessive intervention from humans, environmental and fishery officials say winter fish kills on Iowa’s shallow lakes during long or particularly cold winters are common.
Mike Hawkins, Fisheries Biologist with the Iowa Department of Natural Resources in Spirit Lake, said last month of conditions on Dickinson County’s lakes, that fish species have evolved under these conditions and their populations usually rebound quickly.
“Even with aeration, lakes still winterkill. Harsh Iowa winters can trump all our best efforts,” Hawkins said in a statement at the time.
Hawkins addressed questions last month about turning aerators on and off. A few systems were started and then turned off after large portions of a lake opened back up.
“Open holes and weak areas prevented us from finding a safe time to start the aerators,” Hawkins said at the time.
Long-time residents told the Estherville News winter kills on Emmet County lakes seems to happen once each five to 10 years.
The Estherville News will continue to follow and report on this story as more information becomes available.