Keystone effects of the endangered Stephens' kangaroo rat (Dipodomys stephensi) [An article from: Biological Conservation]

This digital document is a journal article from Biological Conservation, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
Kangaroo rats (Dipodomys) have been argued to exert keystone effects because they interact strongly with other species, and their removal results in major changes in community structure. We evaluated the nature and magnitude of such impacts by the endangered Stephens' kangaroo rat (Dipodomys stephensi), employing an exclosure experiment to determine how the removal of this species impacted relative cover by vegetation, plant species diversity, abundance of a dominant annual plant genus (Erodium), and predation of seeds from artificial trays. Fifteen months of D. stephensi removal resulted in significant increases in herb cover and Erodium abundance, and significant declines in bare ground and in seed predation. These results support the hypothesis that D. stephensi has major impacts on plant community structure and seems to function as a keystone species. It remains to be seen how the loss of this species from much of its range will influence local community composition and dynamics.