As of 2013, the USFWS had identified 332 species of wildlife on the refuge. Most of these species, however, existed only in very low numbers. Beginning in 2011, the USFWS began implementing a plan to remove invasive plant species and restore native plants on most of the refuge. About two-thirds of the refuge consists of mixed-grass and shortgrass prairie, while the remainder is a mix of forest, shrubland, and lakes, streams, and riparian areas. A large number of man-made features dot the landscape, including irrigation ditches, lakes and ponds, and former homesteads.