Jeff Foott / Little Missouri River, Theodore Roosevelt National Park, North Dakota

Jeff Foott / Sandstone rock formations, Theodore Roosevelt National Park, North Dakota

Yva Momatiuk & John Eastcott / Black-tailed Prairie Dog (Cynomys ludovicianus) on alert, Theodore Roosevelt National Park, North Dakota

Tim Fitzharris / American Bison (Bison bison) herd grazing on shortgrass praire near Scoria Point, Theodore Roosevelt National Park, North Dakota

Jeff Foott / American Bison (Bison bison) female and bull, Theodore Roosevelt National Park, North Dakota

Jeff Foott / American Bison (Bison bison) bull and females, Theodore Roosevelt National Park, North Dakota

Jeff Foott / American Bison (Bison bison) bull calling, Theodore Roosevelt National Park, North Dakota

Jeff Foott / American Bison (Bison bison) bull calling, Theodore Roosevelt National Park, North Dakota

Jeff Foott / Round boulders, Theodore Roosevelt National Park, North Dakota

Jeff Foott / Round boulder, Theodore Roosevelt National Park, North Dakota

Jeff Foott / Wood Lily (Lilium philadelphicum) flowers, Theodore Roosevelt National Park, North Dakota

Jeff Foott / Sandstone rock formations, Theodore Roosevelt National Park, North Dakota