The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad.

This award will support a twenty-four-month research fellowship by Dr. Ana D. Davidson to work with Dr. Gerardo Ceballos at Universidad Nacional Autonoma de Mexico (UNAM) in Mexico.

Grasslands are among the most imperiled ecosystems in the world due to agricultural intensification, desertification, and the loss of native species. In order to manage and conserve these systems in the face of multiple, and often conflicting interests, there is a critical need to understand the primary mechanisms that drive grassland ecosystem dynamics and biodiversity. Megaherbivores and small burrowing herbivores are known to play key roles in the structure and function of grasslands worldwide. Although domestic livestock have replaced native megaherbivores throughout much of the world, surprisingly little is known about their interactive effects with native wildlife and the consequent effects on grassland systems. The primary objective of this research will be to determine the independent and interactive effects of domestic megaherbivores (cattle) and small herbivores (prairie dogs) on semi-arid grassland ecosystems in the Janos region of northern Chihuahua, Mexico. This research will manipulate cattle and prairie dogs simultaneously using a controlled, long-term, replicated experiment. This multidisciplinary research will evaluate the impacts of cattle and prairie dogs on soils, plants, and animals, using a 2x2 factorial design. This region supports the largest remaining colony of black-tailed prairie dogs in the world, and provides a rare opportunity to conduct large-scale manipulative research in the context of a largely intact grassland ecosystem that retains a high diversity of threatened and endangered species. This postdoctoral fellowship will be part of a long-term project conducted by a team of researchers from the United States and Mexico. The PI's role will be to design, implement, and lead this research and develop a long-term collaboration with the host in order to follow the effects of this important research over time. The research will advance our knowledge of ecology by assessing the interactive effects of key herbivores on grassland ecosystem structure and function. The role of herbivory in the desertification of semi-arid grasslands remains one of the most important questions in ecology and conservation worldwide.

This research is expected to have global implications given the common co-occurrence of domestic megaherbivores and small herbivores in grasslands worldwide. This project will directly benefit the US/Mexico borderland region by promoting: 1) international collaboration among scientists and managers; 2) education and outreach to local communities; and 3) preservation of the region's grassland ecosystem by providing needed information on the functioning of semi-arid grasslands to management and conservation agencies.

National Science Foundation (NSF)
Office of International and Integrative Activities (IIA)
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Susan Parris
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Davidson Ana D
United States
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