Location: Rangeland Resources & Systems ResearchTitle: Testing for thresholds in a semiarid grassland: The influence of prairie dogs and plague Author
Submitted to: Rangeland Ecology and Management
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/16/2014
Publication Date: 11/14/2014
Publication URL: http://handle.nal.usda.gov/10113/60374
Citation: Augustine, D.J., Derner, J.D., Detling, J. 2014. Testing for thresholds in a semiarid grassland: The influence of prairie dogs and plague. Rangeland Ecology and Management. 67:701-709.
Interpretive Summary: Black-tailed prairie dogs are believed to strongly affect rangeland vegetation by substantially reducing the cover of grasses that are palatable to livestock, and exposing bare soil. These conditions may or may not be reversible after prairie dogs are removed from the site. Working in the shortgrass steppe of northeastern Colorado, we studied how the length of time that an area is occupied by prairie dogs (varying from 1 to 10 years) affects whether and how vegetation conditions can recover after prairie dogs are removed. Where prairie dogs have occupied a site for 1 - 4 years, vegetation recovered rapidly to conditions similar to rangeland that was not affected by prairie dogs. Where prairie dogs had occupied a site for 7 - 10 years, vegetation had undergone much greater changes in terms of grass and forb cover, but most of these changes were reversible over a 5-year period following prairie dog removal. Our findings show that the kinds of vegetation changes caused by prairie dogs are largely reversible, at least at sites where prairie dogs have been present for 10 years or less.
Technical Abstract: State and transition models for semiarid grasslands in the Great Plains of North America suggest that the presence of herbivorous black-tailed prairie dogs (Cynomys ludovicianus) on a site (1) creates a vegetation state characterized by increased dominance of annual forbs and unpalatable bunchgrasses, and increased bare soil exposure, and (2) requires long-term (>40 yr) prairie dog removal to transition back to a vegetation state dominated by palatable perennial grasses. Here, we examine (1) how the recent history of prairie dog occupancy on a site (1 to 10 years) influences the magnitude of prairie dog effects on vegetation composition, and (2) how occupancy history affects vegetation dynamics following removal of prairie dogs.