IS A DIVERSE GRASSHOPPER COMMUNITY BENEFICIAL TO THE HEALTH AND FUNCTIONING OF RANGELAND ECOSYSTEMS

Enclosures for manipulating grasshopper diversity.

Enclosures for manipulating grasshopper diversity.

Sustainable grazing systems depend upon healthy, functioning rangeland ecosystems. Grasshoppers are an important, native component of these rangeland systems, but they compete with livestock for forage. Grasshopper outbreaks often trigger chemical control measures with the use of broad spectrum pesticides that kill insects indiscriminately. However, most grasshopper species are not pests and may actually be beneficial. Individual grasshopper species can increase primary production, nutrient cycling, and influence soil microbial communities. However, the role of grasshopper diversity on rangeland ecosystem processes is unknown. Furthermore, we do not understand how environmental factors like productivity mediate these responses. Our long-term goals are to determine: (1) the role of grasshopper diversity in rangeland ecosystems and (2) how the effects of grasshopper diversity vary with primary productivity. Here, we propose a seed grant to: (1) examine the effects of grasshopper species and functional richness on rangeland ecosystem processes (decomposition, microbial communities, nutrient cycling), with a manipulative, 2-year field experiment, and (2) collect baseline data on plant and grasshopper communities along a latitudinal gradient. We will use these data in a future USDA proposal examining the role of grasshopper diversity to rangeland ecosystems along a latitudinal gradient. Our research will lead to better understanding of the role of grasshoppers and grasshopper diversity in rangeland ecosystems. This will provide information on insect-plant interactions, mechanisms of plant responses to insects, and improved biologically-based grasshopper management approaches.

This research is supported by Agricultural and Food Research Competitive grant no. 2016-67014-25257 from the USDA-NIFA.