The Prairie Dog Story: Do We Have It Right
2004
Vermeire, L.T. | Heitschmidt, R.K. | Johnson, P.S. | Sowell, B.F.
As public and scientific interest in black-tailed prairie dogs has grown, views about their ecological role have become polarized. We evaluated three claims frequently made concerning the status of black-tailed prairie dogs and their interactions with other species: (1) that black-tailed prairie dogs historically occupied 40 million to 100 million hectares (ha) and now occupy only 1 to 2 percent of their former range, (2) that large ungulates preferentially forage on prairie dog colonies, and (3) that prairie dogs do not reduce carrying capacity for large herbivores. The conclusion that prairie dogs historically occupied up to 100 million ha is not supported by the literature, and the more conservative figure of 40 million ha is based on estimates from the early 20th century, when prairie dog populations were artificially high as a result of human activities. Prairie dog activity is not unique in facilitating grazing by large herbivores; and selection of prairie dog colonies for foraging is limited to specific conditions, including colony age, proximity, and season of the year. Finally, prairie dogs reduce carrying capacity for large herbivores by consuming forage, clipping plants to increase visibility, building mounds, and changing plant cover and species composition.
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