The Iowa Department of Natural Resources (DNR) is investigating an apparent fish kill in north Iowa.
DNR staff began their investigation Wednesday into dead brown trout found below a storm water drain and flows into Otter Creek in West Union. The dead trout ranged in size from two to 15 inches and the DNR says it appears only naturally reproducing trout were affected.
The DNR says the fish kill extended at least a mile downstream and field tests could not determine a cause. They added that West Union residents reported seeing dead fish around 3 p.m. Tuesday.
Investigators are encouraging people to call in fish kills as early as possible to the 24-hour spill line at 515-725-8694 so DNR staff can determine the pollutant source before it washes downstream.