Several people who made presentations to the committee compared the condition of the northern range unfavorably with that on nearby ranches. Such comparison, however, reflects a confusion of values. Ranching seeks to maximize production for human use, whereas YNP seeks to preserve natural ecological processes. For example, within YNP, aspen is an important landscape element—it is an aesthetically pleasing tree that grows in groves on the hillsides and shows spectacular fall colors. It also is important as habitat for a diversity of bird species (Mueggler 1988, Pojar 1995). Willow, by comparison, is a rather plain plant that most lay visitors to YNP do not notice or might consider an ordinary “bush” if they did. Nevertheless, willow communities may prevent stream-bank erosion and subsequent changes in stream-channel morphology and are a food source for browsers and habitat for many other riparian species. Critics of the park’s natural regulation policy particularly emphasize the adverse effects of elk on streamside willows, which they maintain are excessive and are leading to erosion of northern range streams (Kay 1990, Chadde and Kay 1991).

ORGANIZATION OF THIS REPORT

To present a perspective for understanding current conditions in YNP, Chapter 2 describes historical conditions in the GYE, including climate, geological, and landscape conditions. Chapters 3 and 4 give an ecological context in which park management strategies are conducted, including a review of vegetation, possible driving factors, and processes related to ungulate population dynamics. Chapter 5 is a synthesis chapter that reviews overarching questions related to the problem at hand, and it presents the committee’s conclusions and recommendations.



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