Photo by Barbara Sugarman.

Influence of Black- Tailed Prairie Dog Colonies on Vegetation and Cattle Movement in the Marathon Basin, Texas

Cullom Simpson, Whitney Gann, Bonnie Warnock, and Louis A. Harveson

The Black-tailed prairie dog (Cynomys ludovicianus) plays an important role in preserving biological stability in western grasslands. Unfortunately, their current range has decreased by 98% throughout North America. Public opinion on potential competition for forage resources between prairie dogs and cattle influences conservation and management strategies for these native herbivores. Understanding the ecological relationship between prairie dogs, cattle and rangelands is important to sound species management.

Our objectives for this study included, evaluating movement and grazing patterns of cattle in pastures with varying ratios of prairie dog and non-prairie dog colony, assessing spatial variation and trade-offs between forage quality and quantity in and out of prairie dog colonies, and documentation of seasonal variation in forage quality and quantity. We collected biomass and vegetation every month starting June 2017, following cattle rotation through three pastures to assess spatial variation, and forage quality and quantity. We rotated 25 cows, 10 of which were equipped with GPS collars, through three pastures with differing amounts of prairie dog colonies to evaluate movement and grazing patterns.

We will implement a cow-calf operation for one year to represent a normal grazing routine common to the Marathon Basin. We will also compare vegetation data on monthly basis for quality and quantity of vegetation inside and outside the prairie dog colony. This data is important to obtain a better understanding of how prairie dog colonies influence cattle movement, alter nutritional content of vegetation, and educate the public about the role of prairie dogs in grassland systems.

Funding sources: The Nature Conservancy and the Borderlands Research Institute.