Research buoys deployed in central Iowa reservoirs

The Iowa Department of Natural Resources and Iowa State University are partnering on new research to understand oxygen and temperature patterns in 20 reservoirs in central Iowa. The study will monitor dissolved oxygen and water temperature during the open-water periods of 2026 and 2027, factors that strongly influence fish habitat and nutrient cycling. Water-temperature and dissolved-oxygen loggers will be deployed on buoys at Big Creek, Hickory Grove, and Rock Creek lakes. Lake users are asked not to disturb the buoys, to remain vigilant while boating, and to follow posted speed limits. The project also includes additional buoys at Big Creek Lake in Polk County to track movement of fish in the upper lake area. This spring, researchers tagged a combined total of 65 walleye, muskellunge, largemouth bass, channel catfish, freshwater drum, and common carp to map habitat as conditions change. Tag retrieval from legally harvested fish should be reported to local DNR fisheries staff. Results are intended to guide future restoration and fisheries management.