State officials are trying to determine the source of a fish kill in northeast Iowa.

The fish kill was discovered over the weekend at Backbone State Park. According to a press release, specialists with Iowa Department of Natural Resources investigated the fish kill Saturday after trout anglers reported seeing dead fish in Richmond Springs and Fenchel Creek. Staff from DNR parks, environmental services and fisheries conducted preliminary tests.

Officials found dead trout and non-game fish, but also saw numerous live fish in several sections of the streams. The source of the fish kill has not yet been identified.

DNR officials said they will continue to look for the cause of the partial fish kill. They believe heavy rains Friday night may have washed contaminants into the streams. Prompt reporting by trout anglers meant investigators could quickly look for a pollutant source.

Early reporting of a fish kill or pollutants in a stream can help DNR trace and stop a fish kill. To notify the DNR, call the local field office or 515-725-8694 after hours.

Backbone State Park is Located in Delaware County, about 2.5 miles north of Dundee.