Black-tailed Prairie Dog - Ecological Role and Threats

Ecological Role and Threats

Black-tailed prairie dogs have been called "ecosystem engineers" due to their influence on the biotic and abiotic characteristics of their habitat, landscape architecture, and ecosystem structure and function. Research suggests black-tailed prairie dogs are a keystone species in some, but not all, geographic areas. Black-tailed prairie dogs enhance the diversity of vegetation, vertebrates, and invertebrates through their foraging and burrowing activities and by their presence as prey items. Grasslands inhabited by black-tailed prairie dogs support higher biodiversity than grasslands not occupied by them. See Ceballos and others for a simplified diagram of black-tailed prairie dog activities and impacts in grassland ecosystem function and biological diversity.

Hundreds of species of vertebrates and invertebrates are associated with black-tailed prairie dog colonies. Vertebrate species richness on their colonies increases with colony size and density. West of the Missouri River in Montana, 40% (100 species) of all vertebrate fauna in prairie habitats rely on black-tailed prairie dog colonies for food, nesting, and/or denning. Rare and declining species, such as the black-footed ferret, swift fox (Vulpes velox), mountain plover (Charadrius montanus), and burrowing owl (Athene cunicularia) are associated with colonies. Because their foraging activities keep plant development in a suppressed vegetative state with higher nutritional qualities, herbivores, including red deer (Cervus elaphus), American bison, pronghorn (Antilocapra americana), and domestic cattle often prefer foraging in black-tailed prairie dog colonies. Animals that depend on herbaceous cover in sagebrush habitat, such as mule deer (Odocoileus hemionus) and sage grouse (Centrocercus spp.), may be deterred by the decreased vegetative cover on black-tailed prairie dog colonies. For a list of vertebrate species associated with black-tailed prairie dog colonies, see.

Biodiversity in shortgrass prairies may be at risk due to the reductions in distribution and occurrence of black-tailed prairie dog. Threats include fragmentation and loss of habitat, unregulated eradication or control efforts, and sylvatic plague. As a result of habitat fragmentation and prairie dog eradication programs, colonies are now smaller and more fragmented than in presettlement times. Agriculture, livestock use, and other development have reduced habitat to 2% of its former range. Fragmented colonies are more susceptible to extirpation, primarily by sylvatic plague. The effect of roads on black-tailed prairie dogs is debatable. Roads may either facilitate or hinder their movement, depending on the landscape setting. Roads may be easy routes for dispersal, but those with heavy automobile use may increase mortality. Roads, streams, and lakes may serve as barriers to sylvatic plague.