The American Bison has long been the symbol of the American West. Photo courtesy of Lang Smith As more people move into the area, the spread of "ranchettes" disturbs plant communities and wildlife populations. Photo courtesy of Tim Crawford

The Greater Yellowstone Ecosystem, Wyoming, U.S.A. Among Yellowstone's diverse wildlife are grizzly bear, American bison, bald eagle and trumpeter swan, and the recently reintroduced gray wolf. It is also home to the world's largest concentration of elk. Even so, 19 animals are now listed under the Endangered Species Act: 6 are endangered, 1 is threatened, and 12 are candidate species. In addition, 7 percent of plants are now considered to be rare. Like never before in its history, the Greater Yellowstone Ecosystem is being threatened on many fronts: habitat fragmentation from residential and commercial development, the effects of overgrazing on vegetation composition, and ecological damage from logging and road building on both public and private lands. The impact of the area's more than 200,000 residents and over 3 million annual visitors is also growing. The GYE presents a unique challenge and opportunity to apply an ecosystem conservation approach to biodiversity conservation. This broad-scale approach is the only realistic way to address threats and apply current ecological knowledge to the multiple, and sometimes contradictory, resource uses of the region. 2 of 3