Home > Greater Yellowstone Ecosystem

1 History

Yellowstone National Park boundaries were arbitrarily drawn in 1872 in hopes of including all regional geothermal basins in the area. No other landscape considerations were incorporated. By the 1970s, however, the grizzly bear's (Ursus arctos) range in and near the park became the first informal minimum boundary of a theoretical Greater Yellowstone Ecosystem that included at least 16,000 km² (4,000,000 acres). Since then, definitions of the greater ecosystem's size have steadily grown larger. A 1994 study listed the size as 76,890 km² (19,000,000 acres), while a 1994 speech by a Greater Yellowstone Coalition leader enlarged that to 80,000 km² (20,000,000 acres).

In 1985 the United States House of Representatives Subcommittees on Public Lands and National Parks and Recreation held a joint subcommittee hearing on Greater Yellowstone, resulting in a 1986 report by the Congressional Research Service outlining shortcomings in interagency coordination and concluding that the area's essential values were at risk.

2 Ecosystem Management by Species

The great ecosystem concept has been most often advanced through concerns over individual species rather than over broader ecological principles. Though 20 or 30 or even 50 years of information on a population may be considered long-term by some, one of the important lessons of Greater Yellowstone management is that even half a century is not long enough to give a full idea of how a species may vary in its occupation of a wild ecosystem.

For example, anecdotal information on grizzly bear abundance dates to the mid- 1800s, and administrators have made informal population estimates for more than 70 years. From these sources, ecologists know the species was common in Greater Yellowstone when EuropeFor the band of the same name, see Europe (band . Europe is a continent forming the westermost part of the Eurasian supercontinent. Europe is bounded to the north by the Arctic Ocean, to the west by the Atlantic Ocean, to the south by the Mediterranean Seans arrived and that the population was not isolated before the 1930sCenturies: 19th century 20th century 21st century Decades: 1880s 1890s 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s Years: 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 Events and trends Technology Jet engine invented Link Trainer invented Sc, but is now. Researchers do not know if bears were more or less common than now.

A 1959Events January-February January 1 Cultivars of plants named after this date must be named in a modern language, not in Latin. January 1 Cuba: Fulgencio Batista flees Havana when forces of Fidel Castro advance January 2 CBS Radio cuts four soap operas: Bac- 1970Events January events January 1 Construction begins on Arcosanti, by Paolo Soleri, in Mayer, Arizona, located 65, miles north of Phoenix, Arizona. January 1 Unix epoch at 00:00:00 UTC. January 12 Biafra capitulates, ending the Nigerian civil war. January bearFor other meanings, see Bear (disambiguation). Ailuropoda Ursus Tremarctos Arctodus A bear is a large mammal of the order Carnivora, family Ursidae . The adjective, ursine is used to describe things of bearlike nature. Physical attributes Common character study suggested a grizzly bear population size of about 175, later revised to about 229.[1] Later estimates have ranged as low as 136 and as high as 540; the most recent is a minimum estimate of 236.[2] Although the Greater Yellowstone population is relatively close to recovery goals, the plan's definition of recovery is controversial. Thus, even though the population may be stable or possibly increasing in the short term, in the longer term, continued habitatA habitat (from the Latin for "it inhabits") is the place where a particular organism usually lives or grows. A biotope is the smallest possible geographic region of a habitat. A biome is the set of flora and fauna which live in a habitat and occupy a cer loss and increasing humanHuman beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. Biologically, they are classified as Homo sapiens ( Latin for knowing man , a primate species of mammal with a highly developed brain. In spiritua activities may well reverse the trend.

Early accounts of pronghorn (Antilocapra americana) in Greater Yellowstone described herds of hundreds seen ranging through most major river valley s. These populations were decimated by 1900, and declines continued among remaining herds. On the park's northern range, pronghorn declined from 500-700 in the 1930s to about 122 in 1968. By 1992 the herd had increased to 536.

Among plants, whitebark pine (Pinus albicaulis) is a species of special interest, in large part because of its seasonal importance to grizzly bears, but also because its distribution could be dramatically reduced by relatively minor global warming. In this case, researchers do not have a good long-term data set on the species, but they understand its ecology well enough to project declining future conservation status. A more immediate, and serious, threat to whitebark pine is an introduced fungal disease, white pine blister rust (Cronartium ribicola), which is causing heavy mortality in the species. Occasional resistant individuals occur, but in the short to medium term, a severe population decline is expected.

Estimates of the decline of quaking aspen (Populus tremuloides) on the park's northern range since 1872 range from 50% to 95%, and perhaps no controversy underway in Greater Yellowstone more clearly reveals the need for comprehensive interdisciplinary research. Several factors are suspected in the aspen's changing status, including Native American influences on numerous mammal species and on fire-return intervals before the creation of the park in 1872; European influences on fire frequency since 1886; regional climate warming; human harvests of beaver and ungulates in the first 15 years of the park's history and of wolve s and other predators before 1930; human settlement of traditional ungulate migration routes north of the park since 1872; ungulate (especially elk) effects on all other parts of the ecosystem since 1900; and human influences on elk distribution in the park.

The Yellowstone hot springs are important for their diversity of thermophilic bacteria. These bacteria have been useful in studies of the evolution of photosynthesis and as sources of thermostable enzymes for molecular biology.