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bulletYellowstone:  Issues for Study

The greater Yellowstone area is a highly complex and biologically diverse ecosystem. It is one of the last ecosystems with an entire pre-European compliment of species in the lower 48 states. Some of the biological components that are most emblematic of Yellowstone’s high ecosystem integrity, such as gray wolves and grizzly bears, are continually shrouded in controversy. Complex issues addressing these fragile resources present difficult management problems with few easy decisions.

Nathan Varley has been living in the Yellowstone ecosystem for over 25 years.  As a naturalist, his extensive experience with natural resource controversy has made him an excellent instructor for the issues that face Yellowstone.  As an instructor, Nathan Varley has taught for several institutions including the Yellowstone Association Institute, Yellowstone Ecosystem Studies, San Francisco State Wildland Studies, Principia College, The Jason Project, and other fine institutions of higher learning.

Nathan Varley has joined existing classes on their trips to Yellowstone to compliment the existing staff, and has also taught groups as the sole instructor for courses.  He offers a range of natural resource topics for study including but not limited to five major Yellowstone issues that are described below. Detailed subject matter concerning the complex management issues for each topic focuses on ecological, social, and political factors that influence management.  Study activities combine presentations by the instructor as well as experts, advocates, and government officials; discussions and debates facilitated by the instructor; readings that include current articles of relevance on all sides of the issue; and extensive field work to experience the landscape, habitats and wildlife.

bulletGray Wolf Recovery Rocky Mountain gray wolves (Canis lupus irremotus) were recently restored to Yellowstone under direction of the 1973 Endangered Species Act. The recovery effort has been tremendously successful and has been hailed as one of the greatest conservation achievements of the century. Among the results are a population of ~200 wolves in 15 packs, unprecedented opportunities to observe and study these predators, and widespread public acceptance. However, the efforts and achievements are not without detractors including local sportsman and livestock growers whose opposition have challenged managers to work in difficult situations. Focus will be on observation of wolves in the field, discussions with wolf biologists and managers, and conversations with local stakeholders including ranchers, wildlife guides, hunters and environmentalists.
bulletGrizzly Bear Preservation  The grizzly bear (Ursus arctos horribilis) is often thought of as the wild symbol of Yellowstone.  It is a top predator that is listed as threatened under the Endangered Species Act. The current population of grizzlies in the greater Yellowstone area, some 300-500 bears, faces many impediments to long-term survival. As a population, these bears are slow-growing, reproducing infrequently. They require large areas to meet their ecological requirements, yet shrinking habitat through road construction and other human developments has left fewer places for bears to exist. Many sources of food are unreliable and face a questionable future as do the bears themselves. Study focuses on travel in grizzly habitats and management areas, identification of some of the critical bear food sources, and observation of bears in the field.  Biologists and managers will present their work to understand and preserve the bears of Yellowstone.
bulletMountain Goat Colonization  Mountain goats (Oreamnos americanus) are not considered native species in the greater Yellowstone area. They were introduced by state game agencies 40-60 years ago to provide recreational opportunities including hunting. Recently goats have colonized areas of Yellowstone leaving managers with questions concerning their impact on native communities. The decision about what to do with the invading goats is muddled in disputes over their exotic species status, potential damage to ecological resources, resounding popularity among park visitors, and lack of scientific documentation to guide management. Viewing mountain goats in their precipitous habitats will accompany discussions of the many issues surrounding goats in Yellowstone, as well as, the greater issue of exotic species invasions.
bulletBison Migration  Yellowstone hosts the last free-ranging bison (Bos bison) herd in North America. They are managed under a policy of natural regulation which allows for natural process to determine the size and health of the herd. But when bison leave Yellowstone and enter the state of Montana they are hazed, captured, or killed for fear of disease transmission to livestock. Some bison carry a brucella organism that causes brucellosis, an infectious disease known to cause cattle to abort their fetuses and to cause undulant fever in humans. However, transmission of the disease requires conditions that rarely, if ever, occur. The park managers, as well as outraged animal rights protesters, have fought the practices of the state in an on-going debate over the future of bison management.  Study includes viewing bison herds in Yellowstone, as well as, visiting areas where bison management takes place to talk with representatives of the various sides of this contentious issue.
bulletBioprospecting for Thermophilic Organisms  Extremophiles, those organisms that live in extreme conditions, are considered to hold great potential for future technological discoveries. Modern industry has recently turned to prospecting in extremophile communities to develop products including chemicals, solvents, and pharmaceuticals. The potential for great discoveries through this activity, known as bioprospecting, looms large with thermophilic (heat-loving) organisms that are associated with Yellowstone’s famous hot springs and geysers. One common bacterium discovered in Yellowstone, thermus aquaticus, has played a central role in the establishment of the biotechnology industry by making DNA fingerprinting and PCR replication possible. The potential for great scientific gains notwithstanding, ethical struggles surround this issue, primarily in terms of advancements at the expense of Yellowstone’s unique thermal resources. Time will be spent at several of Yellowstone’s large geyser basins to learn about thermophilic communities and their potential use.


For more information on study issues presented by Nathan Varley contact him:

Nathan Varley

(406) 223 2152

P. O. Box 769 Gardiner, Montana 59030

Nathan Varley has lived in the Yellowstone area most of his life. He was raised in the small community of Mammoth Hot Springs, the park headquarters. He graduated from Montana State University with BS in biology in 1996. His M. S. degree from the same university was earned in part through the completion of a mountain goat study in Absaroka Range of Montana. Following graduation, he worked several years as a field biologist on the Yellowstone Wolf Recovery Project. Subsequent research and film productions allowed him to also work with bears, wolves, moose, pine marten and river otters. As an instructor and guide, he has led courses through the Yellowstone Institute and Yellowstone Ecosystem Studies in and around the park for many years.


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