Dugout Creek-Yager Slough wildlife areas south of Lake Park, in western Dickinson County, is home to an array of marshes plus two unique and rare habitat types in the state - one of the largest and highest quality wetland fen complexes in Iowa and high-quality remnant prairie.
Unique and rare, fens are a type of wetland featuring groundwater flowing sideways, and percolating to the surface on a hillside through a layer of peat. Fens require thousands of years to develop, supporting many rare plants.
On the surface, fens feel spongy, like a waterbed. At Dugout Creek-Yager Slough, fens follow the natural drainage, seeping from the hillsides.
The rolling prairie and wetlands complex covers more than 1,600 acres, and is home to rare species, including silverweed, arrowgrass, lesser bladderwort and slender arrowgrass. Black terns and northern harriers are here, as are regal fritillaries and Arogos skippers.
To maintain this highly diverse and unique area, staff with the Iowa Department of Natural Resources Great Lakes Wildlife Unit will manipulate the marshes water levels annually to encourage vegetation and to protect the water quality in the wetlands and apply prescribed fire on different segments to manage the prairie.
“Part of Dugout Creek and Yager Slough are federal waterfowl production areas which requires disturbance on 25 percent of the acreage annually and we accomplish that through fire and through targeted haying and grazing with a local producer,” said Chris LaRue, wildlife biologist for the area. “We try to burn 200 or more acres each year for native prairie and grassland management, to meet long term management goals within this unique complex.”
On this nearly cloudless late June morning, bobolinks, dickcissels and meadowlarks can be heard from the prairie. Leadplant, pale purple coneflower, rattlesnake master, indigo, purple prairie clover can be seen.
The area is home to multiple trumpeter swan nests and, recently, to nesting sandhill cranes. Great blue herons, Canada geese and various ducks are gathered on the largely drained 90-acre wetland, that had been lowered to eliminate a carp population. Carp uproot aquatic plants which degrades water quality, and making the wetlands supportive for waterfowl, shorebirds and other wildlife.
Dugout Creek and Yager Slough is dotted with small wetlands ranging from one to 12 acres. A few larger ones ranging from 30 to 40 acres, and the largest, 90 acres. A mix of restored and remnant prairie covers the rolling hills, filling the picturesque landscape with wildflowers and grasses. This complex has always been a popular pheasant hunting area and, occasionally, gray partridge.
Iowa Lakes Community College has an ongoing blandings turtle study that includes Dugout Creek and Yager Slough. Students at Lakeside Lab tour the area for hands on learning about these ecological sites.
The Iowa DNR has partnered with Pheasants Forever, U.S. Fish and Wildlife Service, Iowa Natural Heritage Foundation, Ducks Unlimited and more to support the wetland and upland complex that is Dugout Creek – Yager Slough wildlife area.
Fens
The Iowa DNR’s John Pearson and Mark Leoschke conducted an extensive study of Iowa fens between 1986 and 1991 and found more than 200 fens in varying condition.
In their 1992 article, Floristic Composition and Conservation Status of Fens in Iowa, Journal of the Iowa Academy of Science: JIAS Volume 99, Number 2-3, Article 3, they found about half of the fens supported plant species considered endangered, threatened, or special concern or rare. Approximately 25 fens were outstanding conservation prospects with intact vegetation, high species richness, and rare species. Nearly 40 percent of all potential fen sites had been destroyed by cultivation or drainage; another 30 percent were unknown due to lack of a field visit, but most appear on aerial photographs to be very small, disturbed fragments.