NSF Proposal Abstract PIs: Reichman and Orrock Proposal Title: "The Role of Apparent Competition and Patch Geometry in Mediating the Invasion and Restoration of Grassland Communities".
Biological invasions occur when non-native species become established in areas outside of their original range. Biological invasions have profound ecological impacts and economical costs, causing extinction of native species and shifts in ecosystem function that are estimated to cost over 138 billion dollars per year in the United States alone. This proposal will take place in the grasslands of California, where 9.2 million hectares (almost 25% of the entire state) are dominated by non-native plants. This proposal will examine whether 1) non-native plants fuel increases in native consumers that contribute to the elimination of native plants; and 2) whether landscape-mediated changes in consumer behavior lead to stronger impacts of consumers on native plants. This proposal links the biology of invasions, indirect interactions among plants and consumers, and spatial dynamics to provide novel insight into the forces structuring ecological communities. Moreover, the work outlined in this proposal has broad applied value because it may provide simple "rules of thumb" to aid conservation biologists in prioritizing areas for protection and to guide the design of restoration efforts. More generally, this work will provide insight into how processes that change patch geometry affect the overall course of invasions, which may be critical in contemporary landscapes where fragmentation is changing patch geometry at unprecedented rates.
