Iowa Department of Natural Resources staff is investigating a fish kill on a stream in Sioux County, near the Rolling Hills Golf Course north of Hull.

The fish kill was reported late Wednesday. Preliminary information indicates the fish kill may have occured Tuesday or earlier in an unnamed tributary of Burr Oak Creek. DNR staff have ruled out multiple pollutant sources, but have not found a cause of the fish kill.

(By Mark Buss, KSOU, Sioux Center)