| Summary: | Grassland ecosystems cover 30 % to 40 % of theearth’s terrestrial surface, provide critical habitat for large numbers of species, and support extensive grazing economies on every continent except Antarctica (Coupland 1979, Samson and Knopf 1996). In the United States alone, there are approximately 312 million hectares of rangeland (NRC 1994). Fire, grazing, and climate combine to act as the primary ecosystem drivers in grasslands. In combina-tion with local species interactions, these processes set the stage for the unique local structure and function of the system (Coupland 1979). Grasslands that are used to support graz-ing activities are renewable natural systems, requiring man-agement practices that capitalize on appropriate natural feedbacks and constraints (Fuhlendorf and Engle 2001). This need contrasts significantly with high-input, intensely man-aged row-crop agriculture, in which many of the natural feedbacks found in grazing systems have been irrevocably al-tered. Against this backdrop of grasslands as a renewable system, we address the underlying assumptions and strategies for managing grasshopper populations—models of eco-nomically significant insect pests in rangeland—to assess and highlight the importance of natural feedbacks in devel-oping appropriate ecologically based strategies. Insect grazers such as grasshoppers, locusts, and Mormon crickets are common native components of grasslands world-wide. Major plagues of these insects periodically affect the livelihoods of people on six continents and have been reported throughout recorded history (figure 1). Because they feed on plants, their presence in large numbers often puts them in direct competition with livestock and other grazing herbivores.
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