The Iowa Department of Natural Resources is investigating a fish kill south of Vail. The incident was reported by the Crawford County Engineer, Tuesday afternoon. Officials say many dead fish and a strong smell of manure indicate recent manure application may be the cause of the fish kill. The DNR fisheries staff did a fish kill count Wednesday, finding mostly small fish such as minnows and shiners. About one to two miles of Miller Creek have been affected southeast of its confluence with the Boyer River. The DNR is actively investigating the source of the fish kill and will continue to monitor the situation.