Black-tailed Prairie Dog - Interactions With Domestic Livestock

Interactions With Domestic Livestock

While black-tailed prairie dogs are often regarded as competitors with livestock for available forage, evidence of impacts on rangelands are mixed. Some research suggests they have either neutral or beneficial effects on rangeland used by livestock; however, their effects on rangelands are not uniform. In Cimarron National Grassland in southwest Kansas and adjacent private lands in Baca County, Colorado, some vegetational differences were detected between areas colonized by black-tailed prairie dogs and uncolonized areas, although not all differences were consistent between sample years. Species richness and diversity indices did not differ among colonized and uncolonized sites in either year, nor did the amount of bare ground. The authors conclude while prairie dogs alter shortgrass prairie such that the vegetation of colonies tends to be distinct from adjacent uncolonized areas, “prairie dogs do not substantially alter the essential character of shortgrass vegetation”. Cattle neither significantly preferred nor avoided black-tailed prairie dog colonies in a study in the shortgrass steppe of northeastern Colorado. Cattle used colonies in proportion to the colony's availability, and grazed as intensively on colonies as on areas not occupied by black-tailed prairie dogs.

Competitive interactions between black-tailed prairie dogs and domestic livestock for preferred forage species are unclear. Several studies suggest black-tailed prairie dogs avoid eating many plants that livestock prefer, and prefer many plants livestock avoid. Conversely, on shortgrass prairie in Colorado, cattle and black-tailed prairie dogs had a 64% similarity in annual diets.

Some changes in plant composition brought about by black-tailed prairie dogs may benefit livestock by encouraging an increase in plants more tolerant of grazing, such as needleleaf sedge (Carex duriuscula), sixweeks grass (Vulpia octoflora), and scarlet globemallow. Grazing by black-tailed prairie dogs may also improve the nutritional qualities of some plants. On a shortgrass prairie near Fort Collins, Colorado, plant species diversity was greater inside black-tailed prairie dog colonies than outside of colonies, and perennial grasses such as buffalo grass and forbs increased. While black-tailed prairie dog colonies at Wind Cave National Park typically had lower levels of plant biomass and were dominated by forbs, plants growing on prairie dog colonies had higher leaf nitrogen concentrations than plants in mixed-grass prairie outside colonies. Foraging by black-tailed prairie dogs does not significantly affect steer weights. While forage availability and use by cattle decreased in black-tailed prairie dog foraging areas, steer weight was not reduced significantly in either of two years of study at the USDA's Southern Great Plains Experimental Range near Woodward, Oklahoma. Nutrient cycling, increased soil fertility, and subsequent changes in forage quality partly compensated for reduced forage availability.