In the dry hills, badlands and eroded river valleys in and around Grasslands National Park, a diversity of wildlife, including pronghorns, greater sagegrouse, prairie rattlesnakes and the only remaining black-tailed prairie dog colonies in Canada, can still be found.
Grasslands National Park is rich with diverse populations of wildlife including over twenty species at risk. Once near global extinction, in 2005 Parks Canada re-introduced Plains Bison to the mixed grass prairie of southern Saskatchewan. Playing an essential role in shaping the ecology of the prairie, this conservation herd has the potential to significantly contribute to the continental restoration of the species.
Sources of water in the Park area are limited. Surface waters are derived mainly from spring runoff and vary seasonally. Many creeks flow in the spring and early summer but dry up during the hot, windy summer. The usefulness of surface water sources is greatly limited because much of the substrata consists of marine shales or soft clays with high concentrations of salts or mud in suspension. Potable water is not available within the park.
Catfish and carp are two of the most common fish species that inhabit the Frenchman River, Rock Creek and a few tributaries that maintain water for a part of the year. Painted turtles occur in some numbers along the fresh and standing waters of the Park. Leopard frogs and chorus frogs can also be found.