Yellowstone National Park

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Yellowstone National Park
IUCN Category II (National Park)
Location:	Wyoming, Montana and Idaho, USA
Coordinates:	44°40′0″N, 110°28′0″W
Area:	2,219,789 acres (3,472 mi²/8,987 km²)[1]
Established:	March 1, 1872
Total Visitation:	2,835,649[2] (in 2005)
Governing body:	National Park Service

Yellowstone National Park is a U.S. National Park located in the western states of Wyoming, Montana, and Idaho. Yellowstone is the first national park established in the world and covers 3,472 square miles (8,987 km²), mostly in the northwest corner of Wyoming. The park is famous for its various geysers, hot springs, supervolcano and other geothermal features and is home to grizzly bears, wolves, and free-ranging herds of bison and elk. It is the core of the Greater Yellowstone Ecosystem, one of the largest intact temperate zone ecosystems remaining on the planet. One of the world's most famous geysers, the Old Faithful Geyser, is located in Yellowstone National Park.

Long before any recorded human history in Yellowstone, a massive volcanic eruption spewed an immense volume of ash that covered all of the Western U.S., much of the Midwestern U.S., Northern Mexico and some areas of the Pacific Coast. The eruption dwarfed that of Mount St. Helens in 1980, and left a caldera 52 by 28 miles (85 by 45 km) sitting over a huge magma chamber. Yellowstone has registered three major volcanic eruption events in the last 2.1 million years, with the last event occurring 640,000 years ago. Its eruptions are the largest known to have occurred on Earth during that period, producing drastic climate change in the aftermath.

The park received its name from its location at the headwaters of the Yellowstone River. French trappers gave this river the name "Roche Jaune," probably a translation of the Hidatsa name "Mi tsi a-da-zi". Later American trappers rendered the French name into English as "Yellow Stone." Although it is commonly believed that the river was named for the yellow rocks seen in the Grand Canyon of the Yellowstone, the Native American source name is more likely derived from the yellowish bluffs located near present-day Billings, Montana.

Contents 1 Early history 2 Park creation and later history of the park 3 Geography 4 Geology 5 Biology and ecology 5.1 Flora 5.2 Fauna 6 Forest fires 7 Climate 8 Recreation 9 References 10 External links 11 Webcams

[edit] Early history

The human history of the park begins at least 11,000 years ago when Native Americans first began to hunt and fish in the Yellowstone region. These Paleo-indians were of the Clovis culture and they used the significant amounts of obsidian found in the park to make cutting tools and weapons. Arrowheads made of Yellowstone obsidian have been found as far away as the Mississippi Valley, indicating that a regular obsidian trade existed between local tribes and tribes farther east.^[3] By the time white explorers first entered the region during the Lewis and Clark Expedition in 1805, they encountered the Nez Perce, Crow and Shoshone tribes. While passing through present day Montana, the expedition members were informed of the Yellowstone region to the south, but did not investigate it.^[3]

In 1806 a member of the Lewis and Clark Expedition named John Colter left the Expedition to join a group of fur trappers. After splitting up with the other trappers in 1807, Colter passed through a portion of what later became the park, during the winter of 1807-1808, and observed at least one geothermal area in the northeastern section of the park, near Tower Falls.^[4] After surviving wounds he suffered in a battle with members of the Crow and Blackfoot tribes in 1809, he gave a description of a place of "fire and brimstone" that was dismissed by most people as delirium. The supposedly imaginary place was nicknamed "Colter's Hell." Over the next forty years, numerous reports from mountain men and trappers told of boiling mud, steaming rivers and petrified trees and animals, yet most of these reports were believed at the time to be myth.^[5]

After an 1856 exploration, mountain man Jim Bridger reported observing boiling springs, spouting water, and a mountain of glass and yellow rock. Because Bridger was known for being a "spinner of yarns", these reports were largely ignored. Nonetheless, his stories did arouse the interest of explorer and geologist F.V. Hayden, who, in 1859, started a two-year survey of the upper Missouri River region with United States Army surveyor W.F. Raynolds and Bridger as a guide. After exploring the Black Hills region of in what is now the state of South Dakota, the party neared the Yellowstone region, but heavy snows forced them to turn away. The intervening American Civil War prevented any further organized attempts to explore the region until the late 1860s.^[6]

The first detailed expedition to the Yellowstone area was the Folsom Expedition of 1869, which consisted of three privately funded explorers. The members of the Folsom party followed the Yellowstone River to Yellowstone Lake, and kept a journal of their findings.^[7] Based on the information it reported, in 1870 a party of Montana residents organized the Washburn-Langford-Doane Expedition, headed by the surveyor-general of Montana Henry Washburn. Amongst the group was Nathaniel P. Langford, who would later become known as "National Park" Langford, and a U.S. Army detachment commanded by Lt. Gustavus Doane. The expedition spent about a month exploring the region, collecting specimens, and naming sites of interest. A Montana writer and lawyer named Cornelius Hedges, who had been a member of the Washburn expedition, proposed that the region should be set aside and protected as a National Park, and wrote a number of detailed articles about his observations for the Helena Herald newspaper between 1870-1871. Hedges essentially reinstated comments made in October of 1865 by acting Montana Territorial Governor Thomas Francis Meagher, who had previously commented that the region should be protected.^[8]

[edit] Park creation and later history of the park

In 1871, eleven years after his failed first effort, F.V. Hayden was finally able to make another attempt at his exploration of the region. Now government sponsored, Hayden successfully returned to Yellowstone with a second, larger expedition. He compiled a comprehensive report on Yellowstone which included large-format photographs by William Henry Jackson and paintings by Thomas Moran. This report helped to convince the U.S. Congress to withdraw this region from public auction and on March 1, 1872, President Ulysses S. Grant signed a bill into law that created Yellowstone National Park.^[9]

"National Park" Langford, a member of both the 1870 and 1871 expeditions, was appointed as the park's first superintendent in 1872. He served for five years, but without salary, funding, or staff, he lacked the means to improve the lands or implement any kind of protection to the park. Without formal policy or regulations put into place, he lacked any legal method to enforce such protection were it available to him. This left Yellowstone vulnerable to poachers, vandals, and others seeking to raid its resources. As a result, Langford was forced to step down in 1877.^[10] Having traveled through Yellowstone and witnessed these problems first hand, Philetus Norris volunteered for the position after Langford's exit. Congress finally saw fit to implement a salary for the position as well as a minimal amount of funds to operate the park. Norris used these monies to expand access to the park, building numerous new, albeit crude, roads, as well as further exploring Yellowstone.^[10] He also hired Harry Yount to control poaching and vandalism in the park. Today, Harry Yount is considered the first national park ranger.^[10] These measures still proved to be insufficient in protecting the park though, as neither Norris, nor the three superintendents who followed, were able to properly protect many of Yellowstone's natural resources due to lack of funding and manpower.

The Northern Pacific Railroad built a station at the northern entrance to the park in the early 1880s, increasing visitation to 5,000 by 1883. Visitors in these early years were faced with poor roads and extremely limited services and all access into the park was done on horse or via stagecoach.^[10]

Ongoing poaching and destruction of natural resources continued unabated until the U.S. Army arrived at Mammoth Hot Springs in 1886 and built Camp Sheridan. Over the next 22 years the army constructed permanent structures which became known as Fort Yellowstone.^[10] With the funding and manpower necessary to keep a diligent watch, the army developed their own policies and regulations that provided public access while protecting park wildlife and natural resources. When the National Park Service was created in 1916, it would take its lead largely from the army's successful example. The army turned control over to the National Park Service in 1918.

By 1915, horses were no longer allowed on park roads and almost 1,000 automobiles entered the park that year. Between 1933 and 1941, the Civilian Conservation Corps built the majority of the early visitor centers, campgrounds and developed the current system of park roads. During World War II, staffing and visitation both decreased and many facilities fell into disrepair.^[10] By the 1950s, visitation increased tremendously at most national parks. Park officials implemented Mission 66, an effort to modernize and expand park service facilities to accommodate the increased visitation. Expected to be completed by 1966, in honor of the 50th anniversary of the founding of the National Park Service, Mission 66 construction diverged from the traditional log cabin style and instead used frame construction for housing and in some parks, concrete for visitors centers and related structures.^[11] During the late 1980s, most construction styles in Yellowstone reverted back to the more traditional designs. As of 2007, some of the earliest Mission 66 structures completed at Canyon Village in 1958 are being rebuilt in the traditional style.

In 1959, a powerful earthquake just north of Yellowstone at Quake Lake damaged roads and some structures in the park. In the northwest section of the park, new geysers were found and many existing hot springs became turbid.^[12]

The Yellowstone Fire of 1988 was the largest forest fire in the history of the park. Approximately 793,880 acres (3,212 km²), 36 percent of the parkland was impacted by the fires, leading to a systematic reevaluation of fire management policies. The fire season of 1988 was considered normal until a combination of drought and heat by mid July of that year contributed to an extreme fire danger. In one day alone, on August 20, 1988, strong winds helped fan the flames that consumed more than 150,000 acres (607 km²).^[13]

The expansive cultural history of the park has been documented by the 1,000 archeological sites discovered in the park. The park has 1,106 historic structures and features, and of these Obsidian Cliff and five buildings have been designated National Historic Landmarks.^[1]

Yellowstone was designated an International Biosphere Reserve on October 26, 1976, and a United Nations World Heritage Site on September 8, 1978.

[edit] Geography

Approximately 96 percent of the land area of Yellowstone National Park is located in the state of Wyoming. Another 3 percent is in Montana and the remaining 1 percent is in Idaho. The park is 63 miles (102 km) north to south and 54 miles (87 km) west to east by air. At 2,219,789 acres (898,317 ha), the park is larger than the states of Rhode Island and Delaware combined. Rivers and lakes cover 5 percent of the land area, with the largest waterbody being Yellowstone Lake which covers 87,040 acres (35,400 ha). Yellowstone Lake is up to 400 feet (122 m) deep and has 110 miles (177 km) of shoreline. Sitting at an elevation of 7,733 feet (2,357 m) above sea level, Yellowstone Lake is the largest high altitude lake in North America. 80 percent of the land area of the park is covered by forest and most of the rest is grassland.^[1]

The Continental Divide of North America runs diagonally through the southwestern part of the park. The divide is a topographic feature that separates Pacific Ocean and Atlantic Ocean water drainages. About one third of the park lies on the west side of the divide. The origins of the Yellowstone and the Snake Rivers are adjacent in the park. However, the headwaters of the Snake River are on the west side of the continental divide, and those of the Yellowstone River are on the east side of that divide. As a result, the waters of the Snake River flow to the Pacific Ocean, while those of the Yellowstone find their way to the Atlantic Ocean via the Gulf of Mexico.

The park sits on a high plateau, known as the Yellowstone Plateau, at an average altitude of 8,000 feet (2,400 m) above sea level. The Yellowstone Plateau is bounded on nearly all sides by mountain ranges of the Middle Rocky Mountains, which range from 9,000 to 11,000 feet (2,743 to 3,352 m) in elevation. The highest point in the park is atop Eagle Peak (11,358 ft/3,462 m) and the lowest is along Reese Creek (5,282 ft/1,610 m).^[1] Numerous mountain ranges either border or can be found in the park, including the Gallatin Range to the northwest, the Beartooth Mountains in the north, the Absaroka Mountains to the east, and the Teton Mountains and the Madison Range to the southwest and west. The most prominent summit on the Yellowstone Plateau is Mount Washburn at 10,243 feet (3,122 m).

Yellowstone National Park has one of the world's largest petrified forests, trees which were long ago buried by ash and soil and transformed from wood to mineral materials. 290 waterfalls of at least 15 feet (4.5 m) can be found scattered across the park, the highest being the Lower Falls of the Yellowstone River at 308 feet (94 m).^[1]

Two deep canyons are located in the park, cut through the volcanic tuff of the Yellowstone Plateau by rivers over the last 640,000 years. The Lewis River flows through Lewis Canyon in the south and the Yellowstone River has carved the colorful Grand Canyon of the Yellowstone in its journey north.

[edit] Geology

Main articles: Geothermal areas of Yellowstone, Yellowstone Caldera, and Supervolcano

Yellowstone is at the northeastern end of a U-shaped curve through the mountains, known as the Snake River Plain. This curved plain was created as the North American tectonic plate drifted across a stationary volcanic hotspot beneath the Earth's crust. This hotspot used to be near what is now Boise, Idaho, but over the last 17 million years continental drift of the North America tectonic plate has moved the plate 400 miles (643 km) and now the hotspot's present location is below Yellowstone.^[14]

The Yellowstone Caldera is the largest volcanic system in North America. It has been termed a "supervolcano" because the caldera was formed by exceptionally large explosive eruptions. The current caldera was created by a cataclysmic eruption that occurred 640,000 years ago which released 240 cubic miles (1,000 km³) of ash, rock and pyroclastic materials. This eruption was 1,000 times larger than the 1980 eruption of Mount St. Helens.^[15] A crater nearly a two thirds of a mile (1 km) deep and 52 by 28 miles (85 by 45 km) in area was formed by this explosive event. The welded tuff geologic formation created by this eruption is called the Lava Creek Tuff. The most violent known eruption occurred 2.1 million years ago resulting in the ejection of 588 cubic miles 2,450 km³ of volcanic material, and the geologic formation created by this eruption is called the Huckleberry Ridge Tuff.^[16]

1.2 million years ago, a smaller eruption ejected 67 cubic miles (280 km³) of material, forming the Island Park Caldera and the geologic formation known as the Mesa Falls Tuff.^[15] All three climax eruptions released vast amounts of ash that blanketed much of central North America and fell many hundreds of miles away. The amount of ash and gases released into the atmosphere probably caused significant impacts to world weather patterns and led to the extinction of many species in at least North America. About 160,000 years ago a much smaller climax eruption occurred which formed a relatively small caldera that is now filled in with the West Thumb of Yellowstone Lake. In addition to the last great eruptive cycle, there were two smaller ones which buried much of the caldera under thick lava flows.^[16]

Each eruption is in fact a part of an eruptive cycle that climaxes with the collapse of the roof of a partially emptied magma chamber. This creates a crater, called a caldera, and releases vast amounts of volcanic material, usually through fissures that ring the caldera. The time between the last three cataclysmic eruptions in the Yellowstone area has ranged from 600,000 to 900,000 years, but the small number of such climax eruptions can not be used to make a prediction for the time range for the next climax eruption.

Between 630,000 and 70,000 years ago, Yellowstone Caldera was nearly filled in with periodic eruptions of rhyolitic lavas such as those that can be seen at Obsidian Cliffs and basaltic lavas which can be viewed at Sheepeaters Cliff. Lava strata is most easily seen at the Grand Canyon of the Yellowstone, where the Yellowstone River continues to carve into the ancient lava flows. The canyon is a classic V-shaped valley, indicative of river-type erosion rather than glaciation. Today the canyon is still being eroded by the Yellowstone River.

The most famous geyser in the park, and perhaps the world, is Old Faithful Geyser, located in Upper Geyser Basin, but the park also contains the largest active geyser in the world; Steamboat Geyser in the Norris Geyser Basin. Preserved within Yellowstone are 10,000 geothermal features, including 300 geysers.^[1]

In May 2001, the U.S. Geological Survey, Yellowstone National Park, and the University of Utah created the Yellowstone Volcano Observatory (YVO), a partnership for long-term monitoring of the geological processes of the Yellowstone Plateau volcanic field. YVO maintains a website to disseminate information about research, plans, and events concerning the potential hazards of this geologically active region.^[17]

In 2003, changes at the Norris Geyser Basin resulted in the temporary closure of some trails in the basin. New fumaroles were observed and several geysers showed enhanced activity and increasing water temperatures. Several geysers became so hot that they were transformed into purely steaming features; the water had become superheated, they could no longer erupt normally.^[18] This coincided with the release of reports of a multiple year United States Geological Survey research project which mapped the bottom of Yellowstone Lake, and identified a structural dome that had uplifted at some time in the past. Research indicated that these uplifts posed no immediate threat of a volcanic eruption, as they may have developed long ago and there has been no temperature increase found near the uplifts.^[19] On March 10, 2004, a biologist discovered 5 dead bison which apparently had inhaled toxic geothermal gases trapped in the Norris Geyser Basin by a seasonal atmospheric inversion. This was closely followed by an upsurge of earthquake activity in April 2004.^[20] In 2006, it was reported that the Mallard Lake Dome and the Sour Creek Dome —areas that have long been known to show significant changes in their ground movement— had risen at a rate of 1.5 to 2.4 inches (4 to 6 cm) per year since 2004.^[21] These events inspired a great deal of media attention and speculation about the geologic future of the region. Experts responded to the conjecture by informing the public that there was not any increased risk of a volcanic eruption in the near future.^[22]

Yellowstone has frequent earthquakes, but virtually all of them are undetectable to people. However, there are thousands of small earthquakes every year, including six that have been at least magnitude 6 or greater in historical times. In 1959, a 7.5 magnitude quake struck just outside the northwest boundary of the park. This quake triggered a huge landslide, which caused a partial dam collapse on Hebgen Lake, and immediately downstream, the sediment from the landslide dammed the river and created another lake, known as earthquake lake. Twenty eight people were killed and property damage was extensive in the immediate region. The quake caused some geysers in the northwestern section of the park to erupt, large cracks in the ground formed and emitted steam, and some hot springs normally clear water turned muddy.^[12] A 6.1 magnitude quake struck inside the park on June 30, 1975, but damage was minimal. For three months in 1985, 3,000 minor earthquakes were detected in the northwestern section of the park, during what has been referred to as an earthquake swarm, and has been attributed to minor subsidence of the Yellowstone caldera.^[15]

[edit] Biology and ecology

Main article: Greater Yellowstone Ecosystem

Yellowstone National Park is the centerpiece of the 20 million acre/31,250 mi² (8,093,712 ha/80,937 km²) Greater Yellowstone Ecosystem, a region that includes Grand Teton National Park, adjacent National Forests and expansive wilderness areas in those forests. The ecosystem is the largest remaining continuous stretch of mostly undeveloped pristine land in the United States outside of Alaska, and has been declared to be the largest intact ecosystem in the northern temperate zone on Earth.^[23] With the successful Wolf reintroduction program which commenced in the 1990s, virtually all the original faunal species known to inhabit the region when white explorers first entered the area can still be found here.

[edit] Flora

There are 1,700 species of trees, plants, lichens and other vascular plants native to the park. Another 170 species are considered to be exotic species and are non-native. Of the eight conifer tree species documented, Lodgepole pine forests cover 80 percent of the total forested areas.^[1] Other conifers such as the douglas fir and whitebark pine are found in scattered groves throughout the park. The whitebark pine is currently under threat from a fungus known as white pine blister rust, but not as much as they are in forests well to the north and west. In Yellowstone, about seven percent of the whitebark pine species have been impacted with the fungus compared to almost complete infestations in northwestern Montana. It is believed that the moister conditions found north and west of Yellowstone and the lack of historical levels of wildfire due to increased suppression, are the primary reasons for the decimation of the whitebark pine communities in those areas.^[24] Aspen and willow are the most common species of deciduous tree species yet the aspen forests have declined significantly since the early 20th century.

There are dozens of species of flowering plants that have been identified, most of which bloom between the months of May and September.^[25] Flowers can be found throughout the park during the summer. The Yellowstone Sand Verbena is a rare flowering plant found only in Yellowstone. Closely related to species usually found in much warmer climates, the sand verbena is an enigma. The estimated 8,000 examples of this rare flowering plant all make their home in the sandy soils on the shores of Yellowstone Lake well above the waterline.^[26]

In Yellowstone's hot waters, bacteria form mats consisting of trillions of individuals. These bacteria are some of the most primitive lifeforms on earth. The surfaces of these mats assume bizarre shapes, and flies and other arthropods live on the mats, even in the midst of the bitterly cold winters. Scientists thought that microbes there gained sustenance only from sulfur, but scientists from the University of Colorado at Boulder discovered in 2005 that the sustenance for some species is molecular hydrogen, although there is evidence that this may not be the case for all of these diverse hyperthermophilic species.^[27] Thermus aquaticus is an important bacteria found in the Yellowstone hot springs. It produces an important enzyme that is easily replicated in the lab and is useful in diagnosing hereditary and infectious diseases, as well as identification of genetic fingerprints and a variety of other uses. The retrieval of these bacteria can be achieved with no natural resource impact. Other bacteria in the Yellowstone hot springs may also prove useful to scientists who are searching for cures for various diseases.^[28]

Non-native plants sometimes threaten native species by using up nutrient resources. Though exotic species are most commonly found near areas of the greatest human visitation, such as near roads and at major tourist areas, they have also spread into the backcountry. Generally, most exotic species are controlled by pulling the plants out of the soil or by spraying, both of which are time consuming and expensive.^[29]

[edit] Fauna

Main articles: Animals of Yellowstone, Wolf reintroduction, and Grizzly Bear

Yellowstone is widely considered to be the finest megafauna wildlife habitat in the lower 48 states. There are almost 60 species of mammals in the park, including the endangered gray wolf and the threatened lynx and grizzly bear.^[1] Other large mammals include the bison (buffalo), black bear, elk, moose, mule deer, pronghorn, bighorn sheep and mountain lion (puma).

The relatively large bison populations in the park are a concern for ranchers, who fear that the species can transmit bovine diseases to their domesticated cousins. In fact, about half of Yellowstone's bison have been exposed to brucellosis; a bacterial disease that came to North America with European cattle and may cause cattle to miscarry. The disease has little effect on park bison and no reported case of transmission from wild bison to domestic livestock has ever been filed. However, the Animal and Plant Health Inspection Service (APHIS) has stated that Bison are the "likely source" of the spread of the disease in cattle in Wyoming and North Dakota. Elk also carry the disease, and are believed to have transmitted the infection to horses and cattle.^[30] Bison once numbered between 30 and 60 million individuals throughout North America, and Yellowstone remains one of their last strongholds. Their populations have increased from an estimated 25 in 1901 to 3,600 in 2006.

To combat the perceived threat, National Park personnel regularly harass bison herds back into the park when they venture outside of the area's borders. During the winter of 1996-97, the bison herd was so large that 1,079 bison that had exited the Park were shot or sent to slaughter.^[30] Animal rights activists state that is a cruel practice and that the possibility for disease transmission is not as great as some ranchers maintain. Ecologists point out that the bison are merely traveling to seasonal grazing areas that lie within the Greater Yellowstone Ecosystem that have been converted to cattle grazing; some of which are within United States National Forests, and are leased to private ranchers. APHIS has stated that with vaccinations and other means, that brucellosis can be eliminated from the bison and elk herds throughout Yellowstone.^[30]

After the wolves were extirpated from Yellowstone, the coyote then became the park's top canine predator. However, the coyote is not able to bring down large animals and the result of this lack of a top predator on these populations was a marked increase in lame and sick megafauna.

Starting in 1914, in an effort to protect elk populations, the U.S. Congress appropriated funds to be used for the purposes of "destroying wolves, prairie dogs, and other animals injurious to agriculture and animal husbandry" on public lands. Park Service hunters carried out these orders and by 1926 they had killed 136 wolves. By this time wolves were virtually eliminated from Yellowstone.^[31] Further exterminations continued until the National Park Service ended the practice in 1935. With the passing of the Endangered Species Act in 1973, the wolf was one of the first mammal species listed as endangered.^[31]

By the 1990s, the Federal government had reversed its views on wolves. In a controversial decision by the U.S. Fish and Wildlife Service (which oversees threatened and endangered species), wolves were reintroduced into the park. Reintroduction efforts have been successful with populations remaining relatively stable. In 2005, there were 13 wolf packs, totaling 118 individuals. These figures are down significantly from 2004 but this may be attributable to wolf migration to other nearby areas as the Wyoming state wolf population saw a population increase.^[32] The Greater Yellowstone recovery area had a total of 326 wolves, most of them descended from the 66 wolves reintroduced in 1995-96.^[32] Wolf recovery throughout the states of Wyoming, Montana and Idaho have been so successful that the U.S. Fish and Wildlife Service has proposed delisting the wolf as a threatened and endangered species.^[33]

An estimated 600 grizzly bears live in the Greater Yellowstone Ecosystem, with more than half of the population habitating within Yellowstone. The grizzly is currently listed as a threatened species, however the U.S. Fish and Wildlife Service has announced that they intend to take it off the endangered species list for the Yellowstone region, but will likely keep it listed in areas where it has not yet recovered fully. Opponents of delisting the grizzly are concerned that states might once again allow hunting and that better conservation measures need to be implemented to ensure a sustainable population.^[34]

Population figures for elk in the park are in excess of 30,000; the largest population of any large mammal species in Yellowstone. The northern herd has decreased enormously since the mid 1990s, which has been attributed to wolf predation and causal effects including elk using more forested regions to evade predation, consequently making it harder for researchers to accurately count them.^[35] While the northern herd migrate to southwestern Montana in the winter, the southern population migrates south, and the majority of these elk winter on the National Elk Refuge, immediately southeast of Grand Teton National Park. The southern herd migration is the largest mammalian migration remaining in the U.S. outside of Alaska.

In 2003, the tracks of one female lynx and her cub were spotted and followed for over 2 miles (3.2 km). Fecal material and other evidence obtained were tested and confirmed to be those of a lynx. No visual confirmation was made, however. Lynx have not been seen in Yellowstone since 1998, though DNA taken from hair samples obtained in 2001 confirmed that Lynx were at least transient to the park.^[36] Other rare mammals such as the mountain lion have been reported to have a population estimated at 25, while the wolverine is known to live in the park, actual population figures are unknown.^[37][38] These uncommon and rare mammals provide insight into the health of protected lands such as Yellowstone, and help managers make determinations as to how best to preserve habitats.

Eighteen different species of fish live in Yellowstone, including a core range of the cutthroat trout subspecies known as Yellowstone cutthroat trout; a fish highly sought by anglers.^[1][39] The Yellowstone cutthroat trout has faced several threats since the 1980s, including the illegal intentional introduction of lake trout, a species which consume the smaller cutthroat trout. The cutthroat trout has further faced an ongoing drought, as well as the accidental introduction of a parasite which causes a terminal nervous system disease in younger fish; known as whirling disease. Lake trout are an example of an invasive species of fish that is decimating the native Yellowstone cutthroat trout population in Yellowstone Lake.^[40] Since 2001, all native sport fish species caught in Yellowstone waterways are subject to a catch and release law.^[39] Yellowstone is also home to 6 species of reptiles such as the painted turtle and western rattlesnake and 4 species of amphibians including the Boreal Chorus Frog.^[41]

There have been 311 different species of birds sighted in the park, almost half of which build nests in Yellowstone.^[1] As of 1999, twenty six pairs of nesting bald eagles have been documented in the park. A number of extremely rare sightings of whooping cranes have been recorded, however only three examples of this species are known to live in the Rocky Mountains, out of 385 known worldwide.^[42] Other birds, considered to be species of special concern due to their low population numbers in Yellowstone, include the common loon, harlequin duck, osprey, peregrine falcon and the trumpeter swan.^[43]

[edit] Forest fires

Main article: Yellowstone Fire of 1988

Wildfire is a natural part of most ecosystems, and plants found in Yellowstone have adapted in a variety of ways. Douglas fir contain a thick bark which protects the inner section of the tree from most fires. Lodgepole pines —the most common tree species in the park— generally have cones that are only opened by the heat of fire. Their seeds are held in place by a tough resin, and fire is needed to effectively melt this resin to allow seeds to disperse. Fire clears out dead and down wood, providing fewer obstacles for lodgepole pines to flourish. Whitebark pine and other species tend to grow in colder and moister areas, where fire is less likely to occur. Aspen trees sprout new growth from their roots, and even if a severe fire kills the tree above ground, the roots often survive unharmed as they are insolated from the heat by soil.^[44] Fire ecologists estimate that in natural conditions, grasslands in Yellowstone burned an average of every 20 to 25 years, while forests in the park would experience fire about every 300 years.^[44]

On an average there are about thirty five natural forest fires started each year by lightning and another six to ten by people; in most cases, by accident. Yellowstone National Park has three fire towers in the park, staffed by trained fire fighters during the fire season. The easiest one to reach is the one atop Mount Washburn, though it is closed to the public. The park monitors fire from the air, and relies on visitor reports of smoke and or flames.^[45] The fire towers are staffed almost continuously from late June to mid September, which is the primary fire season. Fires burn with the greatest intensity in the late afternoon and evening. Few fires ever burn more than 100 acres (40 ha) and the vast majority of fires reach only a little over an acre (0.5 ha) before they burn themselves out.^[46] Fire management in the park focuses on monitoring dead and down wood quantities, soil and tree moisture and the weather to determine those areas most vulnerable to fire should one ignite. Current policy is to suppress all human caused fires and to evaluate natural fires as to whether they will be beneficial to the ecosystem. If a fire is considered to be an immediate threat to people and structures, or will burn out of control, then fire suppression is performed.^[47]

In an effort to minimize the chances of out of control fires and threats to people and structures, park employees do more than just monitor the potential for fire. Controlled burns are prescribed fires which are deliberately started to remove dead timber under conditions which allow fire fighters an opportunity to carefully control where and how much wood is consumed. Natural fires also are considered to be prescribed, if they are left to burn. In Yellowstone, unlike some other parks, there have been very few fires deliberately started by employees as prescribed burns. However, over the last 30 years, over 300 natural fires have been allowed to burn naturally. In addition, fire fighters remove dead and down wood and other hazards from areas where they will be a potential fire threat to lives and property, reducing the chances of fire danger in these areas.^[48] Fire monitors also regulate fire through educational services to the public and have been known to temporarily ban campfires from campgrounds during periods of high fire danger.

The common notion in early United States land management policies was that all forest fires were bad. Fire was seen as a purely destructive force and there was little understanding that it was an integral part of the ecosystem. Consequently, until the 1970s, when a better understanding of wildfire was developed, all fires were suppressed. This led to an increase in dead and dying forests, which would later provide the fuel load for fires that would be much harder and some cases impossible to control. Fire Management Plans were implemented, most of which altered the standards of how to address wildfire by detailing that natural fires should be allowed to burn if they posed no immediate threat to lives and property.

After a wet Spring in 1988, by Summer drought began to set in throughout the northern Rockies, creating the driest year on record to that point. Grasses and plants which grew well in the early Summer from the abundant Spring moisture soon turned to dry tinder. The National Park Service began fire fighting efforts to keep the fires under control, but the extreme drought made suppression difficult. Between the 15th and 21st of July, 1988, fires quickly spread from 8,500 acres (3,439 ha) throughout the entire Yellowstone region, which included areas outside the park, to 99,000 acres (40,063 ha) on the park land alone. By the end of the month, the fires were out of control. A number of large fires burned together and on August 20, 1988, the single worst day of the fires, more than 150,000 acres (607 km²) were consumed. Seven large fires were responsible for 95% of the 793,000 acres (320,915 ha) that were burned over the next couple of months. A total of 25,000 firefighters including U.S. military forces participated in the suppression efforts at a cost of 120 million dollars. By the time Winter brought snow that helped extinguish the last flames, the fires had destroyed 67 structures and caused several million dollars in damage.^[13] Though no civilian lives were lost, two personnel associated with the fire fighting efforts were killed.

Contrary to media reports and speculation at the time, the fires killed very few park animals, and surveys indicated that only about 345 elk (of an estimated 40,000-50,000), 36 deer, 12 moose, 6 black bears, and 9 bison died as a result of the fires. Changes in fire management policies were implemented by land management agencies throughout the U.S. based on knowledge gained from the 1988 fires and the evaluation of scientists and experts from various fields. By 1992, Yellowstone had adopted a new fire management plan which observed stricter guidelines for the management of natural fires.^[13]

[edit] Climate

Yellowstone climate is greatly influenced by altitude, with lower elevations generally found to be warmer year round. The record high temperature is 98 °F (37 °C) in 1936, while the coldest temperature recorded was -66 °F (-54 °C) in 1933.^[1] During the Summer months of June through early September, daytime highs are generally in the 70 to 80 °F (20 to 25 °C), and nighttime lows can go below freezing (0 °C); especially at higher altitudes. Summer afternoons are frequently accompanied by thunderstorms. Spring and Fall temperatures range between 30 and 60 °F (0 to 20 °C) with cold nights in the teens to single digits (-5 to -20 °C). Winter in Yellowstone is cold to very cold with high temperatures usually between zero to 20 °F (-20 to -5C °C) and nighttime temperatures are usually below zero (-20 °C) for most of the winter.^[49]

Precipitation in Yellowstone is highly variable, and ranges from 15 inches (38 cm) near Mammoth Hot Springs to 80 inches (200 cm) in the southwestern sections of the park. Snow is possible at any month of the year, and averages 150 inches (380 cm) annually around Yellowstone Lake, to twice that amount at higher elevations.^[49]

Tornados in Yellowstone are extremely rare; however on July 21, 1987, the most powerful tornado recorded in the state of Wyoming touched down in the Teton Wilderness of Bridger-Teton National Forest, and hit Yellowstone National Park. The tornado had wind speeds estimated at 207 to 260 mph (333 to 418 kph) and was classified as an F4 tornado by Ted Fujita— who developed the fujita scale for classifying tornado intensity. The tornado left a path of destruction 1 to 2 miles (1.6 to 3.2 km) wide and 24 miles (38 km) long, and leveled 15,000 acres (6,070 ha) of mature pine forest.^[50]

[edit] Recreation

Yellowstone is one of the most popular national parks in the United States. Since the mid 1960s, at least 2 million tourists have visited the park almost every year.^[2] At peak summer levels, 3,700 employees work for Yellowstone National Park concessionaires, operating lodging, restaurants, gas stations and other tourism related facilities within the park. Another 800 work as permanent or seasonal employees of the National Park Service, while the total number of year round federal employees is approximately 380. Concessionaires manage nine hotels and lodges, with a total of 2,238 hotel rooms and cabins available.^[1]

The vast majority of people visiting Yellowstone are sightseeing the numerous thermal features and wildlife. Park service roads lead to major features around the park, however ongoing reconstruction has produced temporary road closures from time to time. The park is in the midst of a long term, possibly indefinite, road reconstruction effort, which is hampered by a short repair season. In the winter, all roads aside from the one which enters from Gardiner, Montana and extends to Cooke City, Montana are closed to wheeled vehicles.^[51] Park roads are closed to wheeled vehicles from early November to mid April, but some park roads remain closed until mid May.^[52] The park has 310 miles (499 km) of paved roads which can be accessed from 5 different entrances.^[1] There is no public transportation available inside the park, but a number of tour companies can be contacted for guided motorized transport. In the winter, a number of concessionaires operate guided snowmobile and snowcoach tours.^[53] Facilities in the Old Faithful, Canyon and Mammoth Hot Springs areas of the park are very busy during the summer months. Traffic jams created by road construction or by people observing wildlife can result in long delays.

The National Park Service maintains 9 visitor centers and museums and is responsible for maintenance of historical structures and many of the other 2,000 buildings that are in the park. These structures include historical buildings which are National Historical Landmarks such as the Old Faithful Inn built in 1903-04 and the entire Fort Yellowstone - Mammoth Hot Springs Historic District. A historical tour is available at the Fort Yellowstone Historical District of the history of the National Park Service, and the development of the park. Campfire programs, guided walks and other interpretive presentations are available at numerous locations throughout the park in the summer, and on a limited basis during other seasons.

Camping is available at a dozen campgrounds with a more than 2,000 campsites.^[1] Some of the campgrounds allow advance reservations while others are first come, first served. Camping is also available in surrounding National Forests, as well as in Grand Teton National Park to the south. Backcountry campsites are accessible only by foot or by horseback and require a permit. There are 950 miles (1,529 km) of hiking trails available.^[1] The park is not considered to be a good destination for mountaineering due to instability of the volcanic rock which predominates. Visitors with pets are required to keep them on a leash at all times and are limited to areas near roadways and in "frontcountry" zones such as drive in campgrounds.^[54] Around thermal features, wooden and paved trails have been constructed to ensure visitor safety and most of these areas are handicapped accessible.

Throughout the park, thermal features can be dangerous areas and it is important to remain on well marked trails as the ground is oftentimes unstable, especially near geysers and hot springs. The National Park Service maintains a year round clinic at Mammoth Hot Springs and provides emergency services throughout the year. Wildlife in the park should never be approached as many are capable of bodily injury or death.^[55]

Hunting is not permitted in the park, though it is popular in the surrounding National Forests in season. The popularity of fishing has declined since all native game fish species in the park are on a catch and release mandate to protect them from extinction. The park requires a Yellowstone Park fishing license to fish in park waters.^[56] The park prohibits boating on rivers and creeks except for a 5 mile (8 km) stretch of the Lewis River between Lewis and Shoshone Lakes, which is open to non-motorized use only. Yellowstone Lake has a marina and is the most popular boating destination.^[57]

The park is surrounded by other protected lands including Caribou-Targhee, Gallatin, Custer, Shoshone and Bridger-Teton National Forests. The National Park Service's John D. Rockefeller, Jr. Memorial Parkway is to the south of the park and leads to Grand Teton National Park. The famed Beartooth Highway provides spectacular high altitude scenery and is the route one takes if entering the park from the northeast. Nearby communities include West Yellowstone, Montana, Cody, Wyoming, Red Lodge, Montana, Ashton, Idaho, and Gardiner, Montana. The closest air transport is available by way of Bozeman and Billings, Montana, Jackson and Cody, Wyoming and Idaho Falls, Idaho.

[edit] References

[edit] External links

• Yellowstone National Park Official site
• An extensive Yellowstone photographic gallery on the official NPS.gov site Images should be free under public licence for Wiki-pedia use.
• An Interactive Yellowstone Map Includes Points of Interest
• Yellowstone page on Stromboli online
• Yellowstone National Park Wildland Fire Images - Fires of 1988 public domain images.
• USGS: Volcanic History of the Yellowstone Plateau Volcanic Field
• Tracking Changes in Yellowstone's Restless Volcanic System, U.S. Geological Survey, Fact Sheet 100-03, 2004
• Buffalo Field Campaign, working to stop the slaughter of Yellowstone's wild free roaming buffalo
• Life at high temperatures - An introduction to Yellowstone's thermophilic bacteria.
• Primal Nature Essay: Impact of the Reintroduction of Wolves in Yellowstone
• Scientific American Magazine (June 2004 Issue) Lessons from the Wolf
• Yellowstone Park trail and building lookup map
• Yellowstone Newspaper - all current news in Yellowstone
• Yellowstone National Park travel guide from Wikitravel

[edit] Webcams

• Old Faithful Geyser
• Mammoth Hot Springs
• Mount Washburn

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