Grand Teton National Park

Grand Teton National Park
IUCN Category II (National Park)
The John Moulton Barn and Teton Range
Location	Teton County, Wyoming, USA
Nearest city	Jackson
Coordinates	43°00′00″N 110°42′03″W
Area	Approximately 310,000 acres (1,300 km2)
Established	February 26, 1929
Visitors	2,669,374 (in 2010)
Governing body	National Park Service

Grand Teton National Park is a United States National Park located in northwestern Wyoming, U.S. The Park consists of approximately 310,000 acres (130,000 ha) and includes the major peaks of the 40-mile (64 km) long Teton Range as well as most of the northern sections of the valley known as Jackson Hole. Only 10 miles (16 km) south of Yellowstone National Park, the two parks are connected by the National Park Service managed John D. Rockefeller, Jr. Memorial Parkway. These three protected areas in conjunction with surrounding National Forests constitute the Greater Yellowstone Ecosystem, which at almost 18,000,000 acres (7,300,000 ha), is one of the largest intact mid-latitude temperate ecosystems in the world.

Human history of the Grand Teton region dates back at least 11,000 years, when the first nomadic hunter-gatherer Paleo-Indians would migrate into the region during warmer months in pursuit of food and supplies. In the early 19th century, the first caucasian explorers encountered the eastern Shoshone natives. Between 1810 and 1840, the region attracted various fur trading companies which vied for control of the lucrative beaver fur. Organized U.S. Government explorations to the region commenced in the 1870s as an offshoot of exploration in Yellowstone. The first permanent settlers in Jackson Hole arrived in the 1880s. Efforts to preserve the region as a national park commenced in the late 19th century and by 1929, Grand Teton National Park was established, protecting the major peaks of the Teton Range. The valley of Jackson Hole remained in private ownership until conservationists led by John D. Rockefeller, Jr. in the 1930s began purchasing land in Jackson Hole to be added to the existing national park. Against public opinion and with repeated congressional efforts to repeal it, much of Jackson Hole was also set aside for protection as Jackson Hole National Monument in 1943. In 1950 the monument was abolished and most of the monument acreage was added to Grand Teton National Park.

Grand Teton National Park is named for Grand Teton which is the tallest mountain in the Teton Range. At 13,775 feet (4,199 m), Grand Teton rises abruptly more than 7,000 feet (2,100 m) above Jackson Hole and is almost 850 feet (260 m) higher than Mount Owen, the second highest summit in the range. The park has numerous lakes, including 15 miles (24 km) long Jackson Lake as well as streams of varying length and the uppermost reaches of the Snake River. Though in a state of recession, a dozen named small glaciers persist at the higher elevations, and can be found only near the highest peaks in the range. Some of the rocks found in the park are the oldest found in any U.S. national park and have been dated at nearly 2.7 billion years.

Being an almost pristine ecosystem, the same species of flora and fauna that have existed since prehistoric times can still be found in Grand Teton. More than 1000 species of vascular plants, dozens of species of mammals, 300 species of birds, more than a dozen fish species and even reptiles and amphibians exist. Due to various changes in the ecosystem, some of which are human induced, efforts to provide enhanced protection to some subspecies of cutthroat trout and the increasingly threatened Whitebark Pine, have been implemented.

Recreational opportunities abound and the Park is a highly popular destination for mountaineering, hiking, fly fishing and other pursuits. Backcountry camping is available by permit and is highly regulated to prevent overcrowding, while more than 1000 drive in campsites can be found throughout the park. Grand Teton has several visitor centers which are managed by the National Park Service and contract facilities which operate motels, lodges, gas stations and marinas.

Human history

Paleo-Indians and Native Americans

Evidence of hunter-gatherer Paleo-Indian seasonal settlement in what is now Grand Teton National Park indicates that the first humans arrived more than 11,000 years ago. Jackson Hole valley climate then was likely more alpine and colder than the semi-arid climate found today, so the first humans were likely migratory, spending summer months in Jackson Hole and wintering in the valleys west of the Teton Range. Along the shores of Jackson Lake, fire pits, tools and what are believed to have been fishing weights have been discovered. One of the tools is similar to those associated with the Clovis culture which is believed to have existed approximately 11,500 years ago. Some of the tools are made of obsidian which chemical analysis indicates was from sources near present day Teton Pass which is south of where Grand Teton National Park is located. Though obsidian was also available north of Jackson Hole, virtually all the obsidian spear points found are from a source to the south, indicating that the main seasonal migratory route for the Paleo-Indian and later cultures was from the south. Elk, which winter on the National Elk Refuge at the southern end of Jackson Hole and head north into higher altitudes during spring and summer, follow a similar migratory pattern to this day. From 11,000 to about 500 years ago, there is little evidence of change in the migratory patterns amongst the Native American groups in the region and no evidence that indicates any permanent human settlement.

When White American explorers first entered the region in the first decade of the 19th century, they encountered the eastern tribes of the Shoshone people. Most of the Shoshone that lived in the mountain vastness of the greater Yellowstone region continued to be pedestrian while other groups of Shoshone that resided in lower elevations had limited use of horses. The Shoshone that lived in the Jackson Hole region were known within their culture as the "Sheep-eaters" or "Tukudika" as they referred to themselves since a main staple of their diet was the Bighorn Sheep. The Shoshones of the region continued to follow the same migratory pattern of their predecessors and have been documented as having a close spiritual relationship with the Teton Range. A number of stone enclosures on some of the peaks, including on the upper slopes of Grand Teton (known simply as The Enclosure) are believed to have been used by Shoshone during vision quests. In 1868, the mountain dwelling Shoshone were relocated to the Wind River Indian Reservation east of the Wind River Range in Wyoming.

Fur trade exploration

The Lewis and Clark Expedition (1804–1806) passed well north of the Grand Teton region. During the expedition's return trip from the Pacific Ocean, expedition member John Colter was given an early discharge so he could join two fur trappers who were heading west in search of beaver pelts. Colter was later hired by Manuel Lisa to lead fur trappers and to explore the region around the Yellowstone River. It is generally believed that during the winter of 1807/08 Colter passed through Jackson Hole and was the first caucasian to see the Teton Range. In 1810, Lewis and Clark expedition coleader William Clark produced a map of the previous expedition as well as travels made by John Colter in 1807, apparently based on discussions between Clark and Colter when the two met in St. Louis, Missouri in 1810. Another map attributed to William Clark indicates John Colter entered Jackson Hole from the northeast, crossing the Continental Divide at either Togwotee Pass or Union Pass and left the region after crossing Teton Pass, probably following the well established Native American trails. In 1931, the Colter Stone, a carved rock in the shape of a head with the inscription "John Colter" on one side and the year "1808" on the other, was discovered in a field in Tetonia, Idaho, which is west of Teton Pass. The Colter Stone has not been authenticated to have been created by John Colter and may have been the work of later expeditions to the region.

The enigmatic Colter Stone, with the inscription "John Colter", was found in a field in eastern Idaho in 1931

John Colter is widely considered the first mountain man and like those that came to the Jackson Hole region over the next 30 years, he was there primarily due to the North American fur trade, and the region was rich with the highly sought after pelts of beaver and other fur bearing animals. Between 1810 and 1811, the Astorians are known to have travelled through Jackson Hole and crossed Teton Pass as they headed east in 1812. British and American fur trading companies vied for control of the fur trade starting in the 1810s as an offshoot of border disputes in the region. One party employed by the British North West Company and led by explorer Donald Mackenzie is believed to have entered Jackson Hole from the west in 1818 or 1819. The Tetons, as well as the valley west of the Teton Range known today as Pierre's Hole, may have been named by French speaking Iroquois or French Canadian trappers that were part of Mackenzie's party. Earlier parties had referred to the most prominent peaks of the Teton Range as the Pilot Knobs, however the French trappers "les trois tetons" (the three breasts) was later shortened to the Tetons.

The Rocky Mountain Fur Company partnership included Jedediah Smith, William Sublette and David Edward Jackson or "Davey Jackson". Jackson oversaw the trapping operations in the Grand Teton region between 1826 and 1830. It is believed that Sublette named the valley east of the Teton Range "Jackson's Hole", (later simply Jackson Hole) for Davey Jackson. As the demand for beaver fur declined and the various regions of the American West became depleted of beaver due to over trapping, American fur trading companies folded but individual mountain men continued to trap beaver in the Jackson Hole region until about 1840. From the mid 1840's until 1860, Jackson Hole and the Teton Range were generally devoid of all but the small populations of native American tribes that had already been there. Most overland human migration routes such as the Oregon and Mormon Trails crossed over South Pass, well to the south of the Teton Range and caucasian influence in the Teton region was minimal until the U.S. Government commenced organized explorations.

Organized exploration and settlement

Main article: Historical buildings and structures of Grand Teton National Park

"The Three Tetons" as seen from west of the Teton Range by members of the Hayden Geological Survey of 1871. One of the earliest photographs of the Teton Range taken by William Henry Jackson in 1872.

The 1859-60 Raynolds Expedition, led by U.S. Army Captain William F. Raynolds was guided by mountain man Jim Bridger and included naturalist F. V. Hayden, who later led other expeditions to the region. It was the first U.S. Government sponsored expedition to enter Jackson Hole. The expedition had been charged with exploring the Yellowstone region, but encountered difficulties crossing mountain passes due to snow. Bridger ended up guiding the expedition south over Union Pass then following the Gros Ventre River drainage to the Snake River and leaving the region over Teton Pass. Organized exploration of the region was halted during the American Civil War but resumed when F. V. Hayden led the well funded Hayden Geological Survey of 1871. Split into two divisions, Hayden explored Yellowstone while a smaller group under James Stevenson explored the Teton region. Along with Stevenson was photographer William Henry Jackson who took the first photographs of the Teton Range. The Hayden Geological Survey is also credited with providing many of the now familiar place names to some of the mountains and lakes in the region. A nearly disastrous and possibly unauthorized expedition led by U.S. Army Lt. Gustavus Cheyney Doane in 1876 enhanced the aura of wildness for which the Tetons were noted. The explorations by early mountain men and subsequent expeditions failed to identify any sources of economically viable mineral wealth in the Teton region. Nevertheless, small groups of prospectors set up claims and mining operations on several of the creeks and rivers. By 1900, all organized efforts to retrieve mineral wealth had been abandoned.

Though the Teton Range was never permanently inhabited, pioneers began settling the Jackson Hole valley to the east in 1884. These earliest homesteaders were mostly single men who endured long winters, short growing seasons and rocky soils which were hard to cultivate. The region was mostly suited for the cultivation of hay and cattle ranching. By 1890, Jackson Hole only had an estimated permanent population of 60. Around 1892 Menor's Ferry was built near present day Moose, Wyoming to provide access for wagons to the west side of the Snake River. Ranching increased significantly from 1900 to 1920 but a series of agricultural related economic downturns in the early 1920s led to the extirpation of wolves in Jackson Hole by the early 1920s as ranchers sought to protect their livelihood. Beginning in the 1920s the automobile provided faster and easier access to areas of natural beauty and old military roads into Jackson Hole over Teton and Togwotee Passes were improved to accommodate the increased vehicle traffic. In response to the increased tourism, dude ranches were established, some new and some from existing cattle ranches, so urbanized travelers could experience life as a cattleman.

Establishment of the park

Grand Teton National Park Dedication in 1929

To the north of Jackson Hole, Yellowstone National Park had been established in 1872. By the late 19th century, conservationists worked to provide further protection to surrounding regions, leading U.S. President Grover Cleveland to create the Teton Forest Reserve, which included a portion of northern Jackson Hole. By 1902, the reserve was combined into the Yellowstone Forest Reserve, then divided again in 1908 by President Theodore Roosevelt, establishing the Teton National Forest, protecting most of the Teton Range. By 1907, the U.S. Bureau of Reclamation had constructed a temporary dam at the Snake River outlet of Jackson Lake. This dam failed in 1910 and a new concrete Jackson Lake Dam replaced it by 1911. The dam was further enlarged in 1916, raising lake waters 39 feet (12 m) as part of the Minidoka Project, designed to provide irrigation for agriculture in the state of Idaho. Though efforts to protect the Teton Range and Jackson Hole as part of an expanded Yellowstone National Park dated back to the late 19th century, proposals to construct more dams on some of the other lakes in Jackson Hole led Yellowstone National Park superintendent Horace Albright to block such efforts. Albright was originally an advocate of the expanded Yellowstone plan which was very unpopular with local residents. By the mid 1920s however, local sentiment had changed once the proposals for a new national park carved out of land currently protected as part of the Teton National Forest and including only the Teton Range and six lakes at the base of the range were put forward. With the general agreement of prominent Jackson Hole residents on this plan, President Calvin Coolidge signed the executive order establishing the 96,000 acres (39,000 ha) Grand Teton National Park on February 26, 1929.

John D. Rockefeller, Jr. and his wife Abby in Grand Teton National Park in 1931

The valley of Jackson Hole remained primarily in private ownership when John D. Rockefeller, Jr. and his wife visited the region in the late 1920s. Horace Albright had hoped to protect the valley of Jackson Hole north of the town of Jackson from commercial exploitation. Rockefeller agreed and through a private enterprise known as the Snake River Land Company by 1927 was buying land in Jackson Hole to be later turned over to the National Park Service. In 1930, this plan was revealed to the residents of the region and was met with strong disapproval. By 1942, John D. Rockefeller, Jr. became increasingly impatient that his land holdings in Jackson Hole might never be part of Grand Teton National Park, so he wrote the Secretary of the Interior Harold L. Ickes and informed him that he may sell the land to another party. Secretary Ickes recommended to President Franklin Roosevelt that the Antiquities Act (which permitted Presidents to set aside land for protection without the approval of Congress) be used to establish a National Monument in Jackson Hole. Roosevelt agreed and the property belonging to the Snake River Land Company along with additional land carved from Teton National Forest became the 221,000 acres (89,000 ha) Jackson Hole National Monument in 1943. The monument and park were adjacent to each other and administered by the National Park Service, but the monument designation ensured no funding allotment, nor provided a level of resource protection equal to the park. Members of Congress repeatedly attempted to have the new National Monument abolished.

Ansel Adams photograph (1941)

After the end of World War II public sentiment shifted in favor of adding the monument to the park. Though there was still much local disagreement, the monument and park were combined in 1950. In recognition for John D. Rockefeller, Jr.'s efforts to establish and then expand Grand Teton National Park, a 24,000 acres (9,700 ha) parcel of land between Grand Teton and Yellowstone National Parks was added to the National Park service in 1972. This land along with the road from the southern boundary of Grand Teton National Park to West Thumb in Yellowstone National Park was designated as the John D. Rockefeller, Jr. Memorial Parkway. In 2001, the Rockefeller family donated the remnants of its JY Ranch for the establishment of the Laurance S. Rockefeller Preserve, dedicated on June 21, 2008.

Park management

Grand Teton National Park is administered by the National Park Service, an agency of the Department of the Interior. Grand Teton National Park oversees the John D. Rockefeller, Jr. Memorial Parkway acreage and the associated scenic highway south of Yellowstone National Park. The park has an average of 100 permanent and 180 seasonal employees. The park also manages 27 concession contracts which provide services such as lodging, restaurants, mountaineering guides, dude ranching, fishing and a boat shuttle on Jenny Lake. Grand Teton National Park works closely with other federal agencies such as the U.S. Forest Service, the U.S. Fish and Wildlife Service, the Bureau of Reclamation, as well as the Federal Aviation Administration, a consequence of Jackson Hole Airport's presence in the park. Initial construction of the airstrip north of the town of Jackson was completed in the 1930s. When Jackson Hole National Monument was designated, it included land that the airport was situated on. After the monument and park were combined, the Jackson Hole Airport became the only commercial airport within a U.S. National Park. Jackson Hole Airport has some of the strictest noise abatement regulations of any airport in the U.S. As of 2010, 110 privately owned property inholdings, many belonging to the state of Wyoming, are located within Grand Teton National Park. Efforts to purchase or trade these inholdings for other federal lands are ongoing and through partnerships with other entities, 10 million dollars is hoped to be raised to acquire private inholdings by 2016. Grand Teton National Park is one of the ten most visited national parks in the U.S., with an average of 2.5 million visitors annually.

Geography

Map of Grand Teton National Park

Grand Teton National Park is located in the northwestern region of the U.S. state of Wyoming. To the north the park is bordered by the John D. Rockefeller, Jr. Memorial Parkway, which is administered by Grand Teton National Park. The scenic highway by the same name passes from the southern boundary of Grand Teton National Park to West Thumb in Yellowstone National Park. Grand Teton National Park covers approximately 310,000 acres (130,000 ha), while the John D. Rockefeller, Jr. Memorial Parkway includes 23,700 acres (9,600 ha). Most of the Jackson Hole valley and virtually all the major mountain peaks of the Teton Range are within the park. The Jedediah Smith Wilderness of Caribou-Targhee National Forest lies along the western boundary and includes the western slopes of the Teton Range. To the northeast and east lie the Teton Wilderness and Gros Ventre Wilderness of Bridger-Teton National Forest. The southeastern border of the park is the location of the National Elk Refuge, where migrating herds of elk from the region spend winters. Privately owned land borders the park to the south and southwest. Grand Teton National Park, along with Yellowstone National Park, surrounding National Forests and related protected areas constitute the 18,000,000 acres (7,300,000 ha) (28,000 sq mi (73,000 km²)) Greater Yellowstone Ecosystem. The Greater Yellowstone Ecosystem spans across portions of three states and is one of the largest intact mid-latitude ecosystem remaining on Earth. By road, Grand Teton National Park is 290 miles (470 km) from Salt Lake City, Utah and 550 miles (890 km) from Denver, Colorado.

Teton Range

Main article: Teton Range

Main article: Canyons of the Teton Range

The Teton Range is the youngest mountain range in the Rocky Mountains, and began forming between 6 to 9 million years ago. The Teton Range runs roughly north to south and rises from the floor of Jackson Hole without any foothills along a 40 miles (64 km) long by 7 to 9 miles (11 to 14 km) wide active fault-block mountain front. The range tilts westward, rising abruptly above Jackson Hole valley which lies to the east but more gradually into Teton Valley to the west. A series of earthquakes along the Teton Fault slowly displaced the western side of the fault upward and the eastern side of the fault downward at an average of 1 foot (0.30 m) of displacement every 300–400 years. Most of the displacement of the fault occurred in the last 2 million years. While the fault is believed to experience up to 7.5 earthquake magnitude events since it formed, it has been relatively quiescent during historical periods, with only a few 5.0 magnitude or greater earthquakes known to have occurred since 1850.

Fault-block mountain formation of the Teton Range and Jackson Hole

In addition to 13,775 ft (4,199 m) high Grand Teton, another nine peaks are over 12,000 ft (3,658 m) above sea level. Eight of these peaks between Avalanche and Cascade Canyons make up the often-photographed Cathedral Group. The most prominent peak north of Cascade Canyon is the monolithic Mount Moran (12,605 feet (3,842 m)) which rises 5,728 feet (1,746 m) above Jackson Lake. To the north of Mount Moran, the range eventually merges into the high altitude Yellowstone Plateau. South of the central Cathedral Group the Teton Range tapers off near Teton Pass and blends into the Snake River Range.

West to east trending canyons provide easier access by foot into the heart of the range as no vehicular roads traverse the range except at Teton Pass, which is south of the park. Carved by a combination of glacier activity as well as by numerous streams, the canyons are at their lowest point along the eastern margin of the range at Jackson Hole. Flowing from higher to lower elevations, the glaciers created more than a dozen U-shaped valleys throughout the range. Cascade Canyon is sandwiched between Mount Owen and Teewinot Mountain to the south and Symmetry Spire to the north and is situated immediately west of Jenny Lake. North to south, Webb, Moran, Paintbrush, Cascade, Death and Granite Canyons slice through Teton Range.

Jackson Hole

Main article: Jackson Hole

The Teton Fault near the base of Rockchuck Peak creates a nearly horizontal line above the trees in the foreground.

Jackson Hole is a 55 miles (89 km) long by 6 to 13 miles (9.7 to 21 km) wide graben valley with an average elevation of 6,800 ft (2,100 m), its lowest point is near the southern park boundary at 6,350 ft (1,940 m). The valley sits east of the Teton Range and is vertically displaced downward 30,000 ft (9,100 m) from corresponding rock layers in it, making the Teton Fault and its parallel twin on the east side of the valley normal faults with the Jackson Hole block being the hanging wall and the Teton Mountain block being the footwall. Grand Teton National Park contains the major part of both blocks. A great deal of erosion of the range and sediment filling the graben, however, yields a topographic relief of only up to 7,700 ft (2,300 m). Jackson Hole is comparatively flat, with only a modest increase in altitude south to north, however a few isolated buttes such as Blacktail Butte and hills including Signal Mountain dot the valley floor. In addition to a few outcroppings, the Snake River has eroded terraces into the valley floor. Southeast of Jackson Lake, glacial depressions known as kettles are numerous. The kettles were formed when ice situated under gravel outwash from ice sheets melted as the glaciers retreated.

Lakes and rivers

Main article: Snake River

Oxbow Bend on the Snake River

Most of the lakes in Grand Teton National Park were formed by glaciers and the majority of these lakes are located at the base of the Teton Range. In the northern section of the park lies Jackson Lake, the largest lake in the park at 15 miles (24 km) long 5 miles (8.0 km) wide and 438 feet (134 m) deep. Though Jackson Lake is natural, the Jackson Lake Dam was constructed at its outlet before the creation of the park (since modified) and the lake level was raised almost 40 feet (12 m) consequently. East of the Jackson Lake Lodge lies Emma Matilda and Two Ocean Lakes. South of Jackson Lake, Leigh, Jenny, Bradley, Taggart and Phelps Lakes can be found near the entrances to the canyons which lead into the Teton Range. Within the Teton Range, smaller lakes are sometimes found in high altitude cirques, and there are more than 100 alpine lakes scattered throughout the high country. Lake Solitude, located at an elevation of 9,035 feet (2,754 m), is in a cirque at the head of the North Fork of Cascade Canyon. Other high altitude lakes can be found at over 10,000 feet (3,000 m) in elevation and a few, such as Icefloe Lake, remain ice clogged for much of the year. The Snake River flows north to south through the park, entering Jackson Lake near the boundary of Grand Teton National Park and John D. Rockefeller, Jr. Memorial Parkway. The Snake River then flows through the spillways of the Jackson Lake Dam and from there southward through Jackson Hole, exiting the park just west of the Jackson Hole Airport. The largest lakes in the park all drain either directly or by tributary streams into the Snake River. Major tributaries which flow into the Snake River include Pacific Creek and Buffalo Fork near Moran and the Gros Ventre River at the southern border of the park. Through the comparatively level Jackson Hole valley, the Snake River descends an average of 19 feet (5.8 m) per mile (1.6 km), while other streams descending from the mountains to the east and west have higher gradients due to increased slope. The Snake River creates braids and channels in sections where the gradients are lower and in steeper sections, erodes and undercuts the cobble stone terraces once deposited by glaciers.

Glaciation

Middle Teton Glacier on the northeast slopes of Middle Teton has numerous crevasses

The major peaks of the Teton Range were carved into their current shapes by long vanished glaciers. Commencing 250,000-150,000 years ago, the tetons went through several periods of glaciation with some areas of Jackson Hole covered by glaciers 2,000 feet (610 m) thick. This heavy glaciation is unrelated to the uplift of the range itself and is instead part of a period of global cooling known as the Ice age. Beginning with the Buffalo Glaciation and followed by the Bull Lake and then the Pinedale glaciation, which ended roughly 15,000 years ago, the landscape that later became Grand Teton National Park is one that has been greatly impacted by past glacial activity. During the Pinedale glaciation, the landscape visible today was created as glaciers from the Yellowstone Plateau flowed south and formed Jackson Lake, while smaller glaciers descending from the Teton range pushed rock moraines out from the canyons and left behind smaller lakes near the base of the mountains. The peaks themselves were carved into horns and arêtes and the canyons were transformed from water eroded V-shapes to glacier carved U-shaped valleys. Approximately a dozen glaciers currently exist in the park, but they are not ancient as they were all reestablished during the Little Ice Age sometime between 1400 and 1850 AD. Of these more recent glaciers, the largest glacier is Teton Glacier which sits below the northeast face of Grand Teton. 3,500 feet (1,100 m) long and 1,100 feet (340 m) wide, the Teton Glacier is sheltered by the tallest summits in the range. Teton Glacier is the best studied glacier in the range, and researchers concluded in 2005 that the glacier would disappear in 30 to 75 years. West of the Cathedral Group near Hurricane Pass, Schoolroom Glacier is tiny but it has well defined terminal and lateral moraines, a small proglacial lake and other traditional glacier features in close proximity to each other.

Geology

Main article: Geology of the Grand Teton area

The geologic feature known as the Black Dike is a diabase intrusion into older gneiss and is visible on the east face of Middle Teton as a dark line bisecting the peak

Grand Teton National Park has some of the most ancient rocks found in any U.S. National Park. The oldest rocks dated so far are 2,680 ± 12 million years old, though even older rocks are believed to exist in the park. Formed during the Archean Eon (4 to 2.5 billion years ago), these metamorphic rocks include gneiss, schist and amphibolites. Metamorphic rocks are the most common types found in the northern and southern sections of the Teton Range. 2,545 million years ago, the metamorphic rocks were intruded by igneous granitic rocks, which are now visible in the central tetons including Grand Teton and the nearby peaks. The light colored granites of the central Teton Range contrast with the darker metamorphic gneiss found on the flanks of Mount Moran to the north. Magma intrusions of diabase rocks 765 million years ago left dikes which can seen on the east face of Mount Moran and Middle Teton. Granite and pegmatite intrusions also worked their way into fissures in the older gneiss. Precambrian rocks in Jackson Hole are buried deep under comparatively recent Tertiary volcanic and sedimentary deposits, as well as Pleistocene glacial deposits.

By the close of the Precambrian the region was intermittently submerged under shallow seas and for 500 million years various types of sedimentary rocks were formed. During the Paleozoic (542 to 251 million years ago) sandstone, shale, limestone and dolomite were deposited. Though most of these sedimentary rocks have since eroded away from the central Teton Range, they are still evident on the northern, southern and western flanks of the range. One notable exception is the sandstone Flathead Formation which continues to cap Mount Moran. Sedimentary layering of rocks in Alaska Basin, which is on the western border of Grand Teton National Park, chronicles a 120 million year period of sedimentary deposition. Fossils found in the sedimentary rocks in the park include algae, brachiopods and trilobites. Sedimentary deposition continued during the Mesozoic (250-65 million years ago) and the coal seams found in the sedimentary rock strata indicate the region was densely forested during that era. Numerous coal seams of 5 to 10 feet in thickness are interspersed with siltstone, claystone and other sedimentary rocks. During the late Cretaceous, a volcanic arc west of the region deposited fine grained ash which later formed into bentonite, an important mineral resource.

From the end of the Mesozoic to present, the region went through a series of uplifts and erosional sequences. A mountain-building episode known as the Laramide orogeny started to uplift western North America 65 million years ago and eventually formed the ancestral Rocky Mountains. This cycle of uplift and erosion left behind one of the most complete non-marine Cenozoic rock sequences found in North America. Conglomerate rocks composed of quartzite and interspersed with mudstone and sandstones were deposited during erosion from a now vanished mountain range which existed to the northwest of the current Teton Range. These deposits also have trace quantities of gold and mercury. During the Eocene and Oligocene, volcanic eruptions from the ancestral Absaroka Range buried the region under various volcanic deposits. Sedimentary basins developed in the region due to drop faulting, creating an ancestral Jackson Hole and by the Pliocene (10 million years ago), an ancestral Jackson Lake known as Teewinot Lake. During the Quaternary, landslides, erosion and glacial activity deposited soils and rock debris throughout the Snake River valley of Jackson Hole and left behind terminal moraines which impound the current lakes. The most recent example of rapid alteration to the landscape occurred in 1925 just east of the park, when the Gros Ventre landslide was triggered by spring melt from a heavy snowpack as well as heavy rain.

Ecology

Flora

Low Larkspur is one of over a hundred flower species found in the park

Grand Teton National Park and the surrounding region host over 1000 species of vascular plants. With an altitude variance of over 7,000 feet (2,100 m), the park has a number of different ecological zones including alpine tundra, the Rocky Mountains subalpine zone where Spruce-fir forests are dominate, and the valley floor, where a mixed conifer and deciduous forest zone occupies regions with better soils intermixed with sagebrush plains atop alluvial deposits. Additionally, wetlands near some lakes and in the valley floor adjacent to rivers and streams cover large expanses, especially along the Snake River near Oxbow Bend near Moran and Willow Flats near the Jackson Lake Lodge. Altitude, available soils, wildfire incidence, avalanches and human activities have a direct impact on the types of plant species in an immediate area. Where these various niches overlap is known as an ecotone.

The range of altitude in Grand Teton National Park impacts the types of plant species found at various elevations. In the alpine zone above the tree line, which in Grand Teton National Park is at approximately 10,000 feet (3,000 m), tundra conditions prevail. In this treeless region, hundreds of species of grass, wildflower, moss and lichen are found. In the subalpine region from the treeline to the base of the mountains, Whitebark Pine, Limber Pine, Subalpine fir, and Engelmann Spruce are dominate. In the valley floor, Lodgepole Pine is most common but Rocky Mountain Douglas-fir, and Blue Spruce inhabit drier areas, while aspen, cottonwood, alder, and willow are more commonly found around lakes, streams and wetlands. However, the tablelands above the Snake River channel are mostly sagebrush plains and in terms of acreage is the most widespread habitat in the park. The sagebrush plains or flats have 100 species of grasses and wildflowers. Slightly more elevated sections of the plains of the northern sections of Jackson Hole form forest islands with one such obvious example being Timbered Island. In this ecotone, forested islands surrounded by sagebrush expanses provide shelter for various animal species during the day and nearby grasses for night time foraging.

The purple colored cones of the Whitebark Pine protect seeds that are an important food source to a number of species

While the flora of Grand Teton National Park is considered to be generally healthy, the Whitebark Pine, and to a lesser degree the Lodgepole Pine, are considered at risk. In the case of the Whitebark Pine, an invasive species of fungus known as White Pine Blister Rust, weakens the Whitebark Pine, making it more susceptible to destruction from endemic mountain pine beetles. Whitebark Pines generally thrive at elevations above 8,000 feet (2,400 m) and produce large seeds that are high in fat content and an important food source for various species such as the grizzly bear, red squirrel and the Clark's Nutcracker. The species is considered to be a keystone and a foundation species; keystone in that its "ecological role (is) disproportionately large relative to its abundance" and foundation in that it has an paramount role that "defines ecosystem structure, function, and process". Whitebark Pine has generally had a lower incidence of blister rust infection throughout the Greater Yellowstone Ecosystem than in other regions such as Glacier National Park and the Cascade Range. The incidence of blister rust on Whitebark Pines in Yellowstone National Park is slightly lower than in Grand Teton. Though blister rust is not in itself the cause of increased mortality, its weakening effect on trees allows native pine beetles to more easily infest the trees, increasing mortality. While general practice in National Parks is to allow nature to take its course, the alarming trend of increased disease and mortality of the vital Whitebark Pine trees has sparked a collaborative effort amongst various government entities to intervene to protect the species.

Fauna

See also: Mammals of Grand Teton National Park

There are 61 species of mammals that have been documented in Grand Teton National Park. This includes the gray wolf which had been extirpated from the region by the mid 1900's, but migrations into the Grand Teton National Park after the reintroduction of the species into adjacent Yellowstone National Park, ensured virtually every indigenous mammal species now exists in the park. Additionally, though not considered native to the immediate region, the mountain goat is considered an "accidental species" because it has only been reported once or twice and is not considered to be indigenous. Of the larger mammals the most commonly found are the elk, which exist in the thousands. Their migration route between the National Elk Refuge and Yellowstone National Park is through Grand Teton, so while easily seen anytime of the year, they are most numerous in the spring and fall. Other ungulates include bison and pronghorn, which is the fastest land mammal in the western hemisphere, commonly found throughout Jackson Hole as well as moose, which tend to stay near waterways and wetlands. Between 100–125 bighorn sheep generally dwell in the alpine and rocky zones of the peaks. Male bighorns can weigh up to 300 pounds (140 kg) including horns they never shed that weigh as much as 40 pounds (18 kg); yet their concave hoofs and tremendous strength help provide sure footing over rocky terrain.

Moose near Leigh Lake

In addition to gray wolves, another 17 species of carnivores reside within Grand Teton National Park including both grizzlies and the more commonly seen American black bear. Relatively common sightings of coyote, river otter, marten and badger and rare sightings of mountain lion, lynx and wolverine are reported annually. Other mammal species include yellow-bellied marmot, least chipmunk, muskrat, beaver, uinta ground squirrel, pika, snowshoe hare, porcupine, and 6 species of bats.

Over 300 species of birds have been sighted in the park including the Calliope Hummingbird, which is the smallest bird species in North America as well as the Trumpeter Swan, which is the largest waterfowl and is commonly seen in the Oxbow Bend area of the Snake River. Both Bald and Golden Eagles and other birds of prey such as the Osprey, Red-tailed Hawk, Kestral and even rare sightings of Peregrine Falcon have been reported. Of the 14 species of owls reported, the most common is the Great Horned Owl, though the Boreal Owl and Great Grey Owl are also seen occasionally. In addition to Trumpeter Swans, another 30 species of waterfowl have been recorded including Blue-winged Teal, Common Merganser, American Wigeon and the colorful but reclusive Harlequin Duck which is occasionally spotted in Cascade Canyon. A dozen species of woodpeckers have been reported, as have a similar number of species of warblers, plovers and gulls. The vocal and gregarious Black-billed Magpie frequents campgrounds while the Steller's Jay and Clark's Nutcracker are more commonly found in the backcountry. The sage covered plains of Jackson Hole are favored areas for Sage Grouse, Brewer's Sparrow and Sage Thrashers, while the wetalnds are frequented by Great Blue Heron, American White Pelican, Sandhill Crane and on rare occasions it's endangered relative, the Whooping Crane.

Snake River fine-spotted cutthroat trout has tiny black spots over most of its body

The Snake River fine-spotted cutthroat trout (or Snake River Cutthroat Trout) is the only native trout species in Grand Teton National Park. It is the only subspecies of cutthroat trout that is exclusively native to large streams and rivers. Various researchers have not been able to identify any genetic differences between the Snake River fine-spotted cutthroat trout and the Yellowstone cutthroat trout, though in terms of appearances the Snake River subspecies has much smaller spots which cover a much larger portion of the body and the two subspecies inhabit different ecological niches. The Snake River fine-spotted cutthroat trout was identified by some researchers as a separate subspecies by the mid 1990's, and is managed as a distinct subspecies by the state of Wyoming, but is not yet recognized as such by the neighboring states of Idaho and Montana. Snake River fine-spotted cutthroat trout is found only in the Snake River and tributaries below the Jackson Lake dam to the Palisades Reservoir in Idaho. Other species of trout such as the rainbow trout and lake trout were all introduced and today a total of five trout species inhabit park waters. Native species of fish include the mountain whitefish, longnose dace, mountain sucker and nonnative species includes the Utah chub and arctic grayling.

Grand Teton National Park has 4 species of reptiles which include the wandering garter snake and the less commonly seen valley garter snake and rubber boa, as well as one lizard species, the sagebrush lizard, that was only first reported in 1992. None of the species are poisonous. Though the park is located at high altitudes and has a cold climate that is generally inhospitable to most amphibian species, six species reside in the park and include the Columbia Spotted Frog, Boreal Chorus Frog, Tiger Salamander and the increasingly rare Boreal Toad and Northern Leopard Frog. A sixth amphibian species, the bullfrog, was introduced. An estimated 10,000 insect species probably frequent the park, they pollinate plants, provide a food source for birds, fish, mammals and other animals, and help in the decomposition of wood. In one example of the importance of insects to the ecosystem, swarms of Army Cutworm Moths die in huge numbers after mating and provide a high fat and protein diet for bears and other predators. One study concluded that when this moth species is most available, bears consume 40,000 moths per day which is roughly 20,000 kcal/day.

Grand Teton National Park is the only U.S. National Park that allows hunting of an animal; in this instance the animal is the elk. This provision was incorporated into law when the Jackson Hole National Monument and the Grand Teton National Park were combined in 1950. While some National Parks in Alaska permit subsistence hunting by indigenous natives and a few other National Park Service managed areas allow it under highly regulated circumstances, this is an otherwise unique policy. The annual elk hunt in Grand Teton is a highly regulated enterprise and only permitted in areas east of the Snake River, while north of Moran, Wyoming, the hunt is permitted east U.S. Route 89. Proponents of continuing the elk hunt claim that the elk herd would become overpopulated, leading to vegetation degradation from overgrazing elk herds. Opponents cite that there has been an increase of predators in Grand Teton National Park such as the wolf and grizzly, rendering the annual hunt unnecessary and potentially more dangerous, since both of these predators are becoming accustomed to feeding on elk carcasses and remains left behind from the hunt.

Fire ecology

The role of wildfire is an important one for plant and animal species diversity. Many tree species have evolved to mainly germinate after a wildfire. Regions of the park that have experienced wildfire in historical times have a higher incidence of species diversity after reestablishment than those regions that have not been influenced by fire. Though the Yellowstone fires of 1988 had minimal impact on Grand Teton National Park, studies conducted before and reaffirmed after that event concluded than the suppression of natural wildfires during the middle part of the 20th Century adversely impacted plant species diversity and natural regeneration of plant communities. One study conducted 15 years before the 1988 Yellowstone National Park fires concluded that human suppression of wildfire had adversely impacted Aspen tree groves and other forest types. The majority of conifer species in Grand Teton National Park are heavily dependent on wildfire and this is particularly true of the Lodgepole Pine. Though extremely hot canopy or crown fires tend to kill Lodgepole Pine seeds, lower severity surface fires usually result in a higher post wildfire regeneration of this species. In accordance with a better understanding of the role wildfire plays in the environment, the National Park Service and other land management agencies have developed Fire Management Plans which provide a strategy for wildfire management and are expected to best enhance the natural ecosytem.

Climate

Grand Teton National Park has a semi-arid climate with the wettest months between November and January, mostly in the form of snow. The park averages 450 inches (1,100 cm) of snow in the mountains and 191 inches (490 cm) in the valley annually. In January, the daily temperature range averages between 26 °F (−3 °C) during the day to 1 °F (−17 °C) at night. During the month of July, the daily temperature range is 80 °F (27 °C) and 41 °F (5 °C). The record high is 93 °F (34 °C) and the record low is −66 °F (−54 °C). Temperatures above the valley in the mountains during the summer average 1 degree cooler for every 1,000 feet (300 m) of altitude gained, so high altitude passes may remain snow covered until mid-July. During the summer months thunderstorms are common, especially over the mountains, however no tornados have ever been reported within the park. The F4 Teton-Yellowstone tornado was a high altitude tornado which touched down northeast of the park on the border of the Teton Wilderness of Bridger-Teton National Forest and Yellowstone National Park.

Tourism

Visitor centers

Craig Thomas Discovery & Visitor Center in Moose, Wyoming

The Craig Thomas Discovery & Visitor Center adjacent to the park headquarters at Moose, Wyoming, is open year round. Opened in 2007 to replace an old and inadequate visitor center, the Craig Thomas facility was built with a combination of federal grants and private donations. Fund raising efforts for an adjoining 154 seat auditorium were nearing completion as of 2011. To the north at Colter Bay Village on Jackson Lake, the Colter Bay Visitor Center & Indian Arts Museum is open from the beginning of May to the early October. The Colter Bay Visitor Center & Indian Arts Museum has housed the David T. Vernon Indian Arts Exhibit, which included a number of historically significant Native American flutes. The David T. Vernon Indian Arts Collection was removed from the facility at the close of the season in 2011 as plans are made to possibly build a new facility.

The Colter Bay Visitor Center was built in 1956 and the David T. Vernon collection has been housed in the facility since 1972. The facility at Colter Bay no longer meets the standards for the proper care and display of the Indian arts collection, but once an appropriate facility is constructed, the exhibits will be returned to the park. South of Moose on the Moose–Wilson Road, the Laurance S. Rockefeller Preserve Center is located on land that was privately owned by Laurance S. Rockefeller and is situated on Phelps Lake. Donated to Grand Teton National Park and opened to the public in 2008, the property was once part of the JY Ranch, the first dude ranch in Jackson Hole. At Jenny Lake, the Jenny Lake Visitor Center is open from mid may to mid September. This visitor center is within the Jenny Lake Ranger Station Historic District and is the same structure photographer Harrison Crandall had constructed as an art studio in the 1920s.

Accommodations

Boats anchored at the Colter Bay Marina

Under license agreement through the National Park Service, various concessionaire entities manage lodging facilities inside the park. The largest such facility is the Jackson Lake Lodge which is managed by the Grand Teton Lodge Company. Located near Jackson Lake Dam, the Jackson Lake Lodge has a total of 385 rooms, meeting facilities, a retail shop and a restaurant. The Grand Teton Lodge Company also manages the Jenny Lake Lodge which consists of exclusive cabins and a restaurant. At Colter Bay Village they oversee numerous tourism related facilities including cabins, a restaurant, a grocery store, a laundry and a marina. South of Jackson Lake Dam the Signal Mountain Lodge is managed by Forever Resorts and provides cabins, a marina, a gas station and a restaurant. The American Alpine Club offers basic hostel dormitory style accommodations primarily reserved for mountain climbers at the Grand Teton Climber's Ranch. Adjacent to the Snake River in Moose, Wyoming, Dornans is an inholding on private land which has year round cabin accommodations and related facilities. Lodging is also available at the Triangle X Ranch, another private inholding in the park and the last remaining dude ranch within park boundaries.

External links

• Grand Teton National Park Official Website
• Grand Teton Association
• Grand Teton National Park at the Open Directory Project