Prairie Dogs and the Architecture of the Grassland
Near Wall, South Dakota
The animal most responsible for shaping the ecology of the shortgrass prairie is smaller than a cat, faster than most things that chase it, and has a name that is technically wrong, because it is not a dog. The black-tailed prairie dog is a large ground squirrel that lives in underground colonies called towns, and whose burrowing, grazing, and constant vigilance has structured the surrounding prairie for millions of years. Prairie dog towns create open, closely cropped patches of grass around their burrow entrances, and those patches attract a specific community of animals.
Burrowing owls nest in abandoned prairie dog burrows. Mountain plovers require the short-grass habitat that prairie dog grazing maintains. Swift foxes hunt the edge of the towns.
And the black-footed ferret evolved to specialize almost entirely on prairie dogs as prey and on their burrows as shelter. When European settlers arrived, they found prairie dog colonies covering vast territories. Estimates of the total area once occupied by black-tailed prairie dogs in North America range widely, into the many millions of acres.
Poisoning campaigns, habitat destruction, and sylvatic plague reduced that coverage by ninety-five percent or more over the twentieth century. Around Wall and across the Buffalo Gap National Grassland, prairie dog towns still survive. Conata Basin to the south is home to what conservation groups call the largest wild population of black-footed ferrets in the world.
A slow drive through the grassland roads in early morning, watching for the sentinel animals standing upright beside their burrow mounds, shows you the animal that built the prairie and that the prairie cannot function fully without.
