The Challenges of Grassland Conservation

Abstract On June 3, 1805, the expedition led by Meriwether Lewis and William Clark reached the junction of Maria’s River and the Missouri, on the High Plains of what is now central Montana. The two men climbed out of the river valley onto adjacent highlands. In their own words, These were the North American High Plains as they existed less than two centuries ago: vast open grasslands, well populated by large numbers of herbivorous animals and their predators. Preceding chapters in this book review what is known about the ecological glue that holds (or once held) Plains and prairie ecosystems together. Careful field research has revealed much about factors such as the role of fire in maintaining certain grasslands, the nature of prairie soils, and the importance of predators in controlling populations of grassland herbivores. Yet many aspects of Great Plains ecology remain elusive, because the Plains cannot be studied as they once existed. Bison and prairie dogs doubtless were major ecological forces, but they and their most important predators are largely gone. Fires that swept the Plains no longer bum with anything like their prehistoric frequency or extent. Fertile soils, once plowed, have blown away.