Big Stone National Wildlife Refuge historically offered a combination of small wetlands and abundant prairie that was critical to waterfowl breeding and nesting. Small wetlands – some temporary and some permanent, provided not only nesting habitat, but food and shelter for egrets, herons, and other waterbirds. The Highway 75 dam created two impoundments (West and East Pools), that added additional 4,250 acres of wetlands to the refuge. Water levels in these two pools can be managed to provide the right mix of plants and waters during different seasons. Refuge wetlands support a diversity of wildlife by providing resting, feeding, and nesting for birds, but also look for snapping turtles, western tiger salamanders, frogs, and toads in these habitat types. Along the banks and edges of these habitats you can also find mink, river otter, and ground squirrels.