Glacier National Park (U.S.)
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| Glacier National Park (U.S.) |
The region that became Glacier National Park was first inhabited by Native Americans. Upon the arrival of European explorers, it was dominated by the Blackfeet in the east and the Flathead in the western regions. Under pressure the Blackfoot ceded the mountainous parts of their treaty lands in 1895 to the federal government; it later became part of the park. Soon after the establishment of the park on May 11, 1910, a number of hotels and chalets were constructed by the Great Northern Railway. These historic hotels and chalets are listed as National Historic Landmarks and a total of 350 locations are on the National Register of Historic Places. By 1932 work was completed on the Going-to-the-Sun Road, later designated a National Historic Civil Engineering Landmark, which provided greater accessibility for automobiles into the heart of the park.
The mountains of Glacier National Park began forming 170 million years ago when ancient rocks were forced eastward up and over much younger rock strata. Known as the Lewis Overthrust, these sedimentary rocks are considered to have some of the finest fossilized examples of extremely early life found anywhere on Earth. The current shapes of the Lewis and Livingston mountain ranges and positioning and size of the lakes show the telltale evidence of massive glacial action, which carved U-shaped valleys and left behind moraines which impounded water, creating lakes. Of the estimated 150 glaciers which existed in the park in the mid-19th century, only 25 active glaciers remained by 2010. Scientists studying the glaciers in the park have estimated that all the glaciers may disappear by 2030 if the current climate patterns persist.
Glacier National Park has almost all its original native plant and animal species. Large mammals such as the grizzly, moose, and mountain goat, as well as rare or endangered species like the wolverine and Canadian lynx, inhabit the park. Hundreds of species of birds, more than a dozen fish species, and a few reptile and amphibian species have been documented. The park has numerous ecosystems ranging from prairie to tundra. Notably, the easternmost forests of western redcedar and hemlock grow in the southwest portion of the park. Large forest fires are uncommon in the park. However, in 2003 over 13% of the park burned.
Glacier National Park borders Waterton Lakes National Park in Canada—the two parks are known as the Waterton-Glacier International Peace Park and were designated as the world's first International Peace Park in 1932. Both parks were designated by the United Nations as Biosphere Reserves in 1976, and in 1995 as World Heritage sites.
According to archeological evidence, Native Americans first arrived in the Glacier area some 10,000 years ago. The earliest occupants with lineage to current tribes were the Flathead (Salish) and Kootenai, Shoshone, and Cheyenne. The Blackfeet arrived around the beginning of the 18th century and soon dominated the eastern slopes of what later became the park, as well as the Great Plains immediately to the east. The park region provided the Blackfeet shelter from the harsh winter winds of the plains, allowing them to supplement their traditional bison hunts with other game meat. Today, the Blackfeet Indian Reservation borders the park in the east, while the Flathead Indian Reservation is located west and south of the park. When the Blackfeet Reservation was first established in 1855 by the Lame Bull Treaty, it included the eastern area of the current park up to the Continental Divide. To the Blackfeet, the mountains of this area, especially Chief Mountain and the region in the southeast at Two Medicine, were considered the "Backbone of the World" and were frequented during vision quests. In 1895 Chief White Calf of the Blackfeet authorized the sale of the mountain area, some 800,000 acres (3,200 km2), to the U.S. government for $1.5 million, with the understanding that they would maintain usage rights to the land for hunting as long as the ceded stripe will be public land of the United States. This established the current boundary between the park and the reservation.
While exploring the Marias River in 1806, the Lewis and Clark Expedition came within 50 miles (80 km) of the area that is now the park. A series of explorations after 1850 helped to shape the understanding of the area that later became the park. In 1885 George Bird Grinnell hired noted explorer (and later well regarded author) James Willard Schultz to guide him on a hunting expedition into what would later become the park. After several more trips to the region, Grinnell became so inspired by the scenery that he spent the next two decades working to establish a national park. In 1901 Grinnell wrote a description of the region in which he referred to it as the "Crown of the Continent". His efforts to protect the land make him the premier contributor to this cause. A few years after Grinnell first visited, Henry L. Stimson and two companions, including a Blackfoot, climbed the steep east face of Chief Mountain in 1892.
In 1891 the Great Northern Railway crossed the Continental Divide at Marias Pass 5,213 feet (1,589 m), which is along the southern boundary of the park. In an effort to stimulate use of the railroad, the Great Northern soon advertised the splendors of the region to the public. The company lobbied the United States Congress. In 1897 the park was designated as a forest preserve. Under the forest designation, mining was still allowed but was not commercially successful. Meanwhile, proponents of protecting the region kept up their efforts. In 1910, under the influence of the Boone and Crockett Club, spearheaded by Club members George Bird Grinnell, Henry L. Stimson, and the railroad, a bill was introduced into the U.S. Congress which redesignated the region from a forest reserve to a national park. This bill was signed into law by President William Howard Taft on May 11, 1910. In 1910 George Bird Grinnell wrote, "This Park, the country owes to the Boone and Crockett Club, whose members discovered the region, suggested it being set aside, caused the bill to be introduced into congress and awakened interest in it all over the country".
Geography:
The park is bordered on the north by Waterton Lakes National Park in Alberta, and the Flathead Provincial Forest and Akamina-Kishinena Provincial Park in British Columbia. To the west, the north fork of the Flathead River forms the western boundary, while its middle fork is part of the southern boundary. The Blackfeet Indian Reservation provides most of the eastern boundary. The Lewis and Clark and the Flathead National Forests form the southern and western boundary. The remote Bob Marshall Wilderness Complex is located in the two forests immediately to the south.
The park contains a dozen large lakes and 700 smaller ones, but only 131 lakes have been named. Lake McDonald on the western side of the park is the longest at 9.4 miles (15.1 km), the largest in area at 6,823 acres (27.61 km2), and the deepest at 464 feet (141 m). Numerous smaller lakes, known as tarns, are located in cirques formed by glacial erosion. Some of these lakes, like Avalanche Lake and Cracker Lake, are colored an opaque turquoise by suspended glacial silt, which also causes a number of streams to run milky white. The lakes of Glacier National Park remain cold year round, with temperatures rarely above 50 °F (10 °C) at their surface. Cold water lakes such as these support little plankton growth, ensuring that the lake waters are remarkably clear. The lack of plankton, however, lowers the rate of pollution filtration, so pollutants have a tendency to linger longer. Consequently, the lakes are considered environmental bellwethers as they can be quickly affected by even minor increases in pollutants.
Two hundred waterfalls are scattered throughout the park. However, during drier times of the year, many of these are reduced to a trickle. The largest falls include those in the Two Medicine region, McDonald Falls in the McDonald Valley, and Swiftcurrent Falls in the Many Glacier area, which is easily observable and close to the Many Glacier Hotel. One of the tallest waterfalls is Bird Woman Falls, which drops 492 feet (150 m) from a hanging valley beneath the north slope of Mount Oberlin.
The rocks found in the park are primarily sedimentary rocks of the Belt Supergroup. They were deposited in shallow seas over 1.6 billion to 800 million years ago. During the formation of the Rocky Mountains 170 million years ago, one region of rocks now known as the Lewis Overthrust was forced eastward 50 miles (80 km). This overthrust was several miles (kilometers) thick and hundreds of miles (kilometers) long. This resulted in older rocks being displaced over newer ones, so the overlying Proterozoic rocks are between 1.4 and 1.5 billion years older than Cretaceous age rocks they now rest on.
One of the most dramatic evidences of this overthrust is visible in the form of Chief Mountain, an isolated peak on the edge of the eastern boundary of the park rising 2,500 feet (800 m) above the Great Plains. There are six mountains in the park over 10,000 feet (3,000 m) in elevation, with Mount Cleveland at 10,466 feet (3,190 m) being the tallest. Appropriately named Triple Divide Peak sends waters towards the Pacific Ocean, Hudson Bay, and Gulf of Mexico watersheds. This peak can effectively be considered to be the apex of the North American continent, although the mountain is only 8,020 feet (2,444 m) above sea level.
The rocks in Glacier National Park are the best preserved Proterozoic sedimentary rocks in the world, with some of the world's most fruitful sources for records of early life. Sedimentary rocks of similar age located in other regions have been greatly altered by mountain building and other metamorphic changes; consequently fossils are less common and more difficult to observe. The rocks in the park preserve such features as millimeter-scale lamination, ripple marks, mud cracks, salt-crystal casts, raindrop impressions, oolites, and other sedimentary bedding characteristics. Six fossilized species of Stromatolites, early organisms consisting of primarily blue-green algae, have been documented and dated at about 1 billion years. The discovery of the Appekunny Formation, a well preserved rock stratum in the park, pushed back the established date for the origination of animal life a full billion years. This rock formation has bedding structures which are believed to be the remains of the earliest identified animal life on Earth.
Climate:
As the park spans the Continental Divide, and has more than 7,000 feet (2,100 m) in elevation variance, many climates and microclimates are found in the park. As with other alpine systems, average temperature usually drops as elevation increases. The western side of the park, in the Pacific watershed, has a milder and wetter climate. Precipitation is greatest during the winter and spring, averaging 2 to 3 inches (50 to 80 mm) per month. Snowfall can occur at any time of the year, even in the summer, and especially at higher altitudes. The winter can bring prolonged cold waves, especially on the eastern side of the Continental Divide. Snowfalls are significant over the course of the winter, with the largest accumulation occurring in the west. During the tourist season, daytime high temperatures average 60 to 70 °F (16 to 21 °C), and nighttime lows usually drop into the 40 °F (4 °C) range. Temperatures in the high country may be much cooler. In the lower western valleys, daytime highs in the summer may reach 90 °F (30 °C).
Wildlife and ecology:
Flora:
Glacier is part of a large preserved ecosystem collectively known as the "Crown of the Continent Ecosystem", all of which is primarily untouched wilderness of a pristine quality. Virtually all the plants and animals which existed at the time European explorers first entered the region are present in the park today.
A total of over 1,132 plant species have been identified parkwide. The predominantly coniferous forest is home to various species of trees such as the Engelmann spruce, Douglas fir, subalpine fir, limber pine and western larch, which is a deciduous conifer, producing cones but losing its needles each fall. Cottonwood and aspen are the more common deciduous trees and are found at lower elevations, usually along lakes and streams.[54] The timberline on the eastern side of the park is almost 800 feet (244 m) lower than on the western side of the Continental Divide, due to exposure to the colder winds and weather of the Great Plains. West of the Continental Divide, the forest receives more moisture and is more protected from the winter, resulting in a more densely populated forest with taller trees. Above the forested valleys and mountain slopes, alpine tundra conditions prevail, with grasses and small plants eking out an existence in a region that enjoys as little as three months without snow cover.[65] Thirty species of plants are found only in the park and surrounding national forests.[64] Beargrass, a tall flowering plant, is commonly found near moisture sources, and is relatively widespread during July and August. Wildflowers such as monkeyflower, glacier lily, fireweed, balsamroot and Indian paintbrush are also common.
The forested sections fall into three major climatic zones. The west and northwest are dominated by spruce and fir and the southwest by redcedar and hemlock; the areas east of the Continental Divide are a combination of mixed pine, spruce, fir and prairie zones. The cedar-hemlock groves along the Lake McDonald valley are the easternmost examples of this Pacific climatic ecosystem.
Whitebark pine communities have been heavily damaged due to the effects of blister rust, a non native fungus. In Glacier and the surrounding region, 30% of the whitebark pine trees have died and over 70% of the remaining trees are currently infected. The whitebark pine provides a high fat pine cone seed, commonly known as the pine nut, that is a favorite food of red squirrels and Clark's nutcracker. Both grizzlies and black bears are known to raid squirrel caches of pine nuts, one of the bears' favorite foods. Between 1930 and 1970, efforts to control the spread of blister rust were unsuccessful, and continued destruction of whitebark pines appears likely, with attendant negative impacts on dependent species.
Fauna:
Virtually all the historically known plant and animal species, with the exception of the bison and woodland caribou, are still present, providing biologists with an intact ecosystem for plant and animal research. Two threatened species of mammals, the grizzly bear and the Canadian lynx, are found in the park. Although their numbers remain at historical levels, both are listed as threatened because in nearly every other region of the U.S. outside of Alaska, they are either extremely rare or absent from their historical range. On average, one or two bear attacks on humans occur each year; since the creation of the park in 1910, there have been a total of 10 bear-related deaths. The number of grizzlies and lynx in the park is not known for certain, but park biologists believed as of 2008 that there were just above 300 grizzlies in the park; a study which commenced in 2001 hopes to determine the number of lynx.[34][69] The exact population figures for grizzlies and the smaller black bear are not known but biologists are using a variety of methods to try to determine an accurate population range. Another study has indicated that the wolverine, another very rare mammal in the lower 48 states, continues to reside in the park.[71] Other large mammals such as the mountain goat (the official park symbol), bighorn sheep, moose, elk, mule deer, white-tailed deer, coyote, and mountain lion are either plentiful or common. Unlike in Yellowstone National Park, which installed a wolf reintroduction program in the 1990s, it is believed that wolves recolonized Glacier National Park naturally during the 1980s. Sixty-two species of mammals have been documented, including badger, river otter, porcupine, mink, marten, fisher, six species of bats and numerous other smaller mammals.
A total of 260 species of birds have been recorded, with raptors such as the bald eagle, golden eagle, peregrine falcon, osprey and several species of hawks residing year round. The harlequin duck is a colorful species of waterfowl found in the lakes and waterways. The great blue heron, tundra swan, Canada goose and American wigeon are species of waterfowl more commonly encountered in the park. Great horned owl, Clark's nutcracker, Steller's jay, pileated woodpecker and cedar waxwing reside in the dense forests along the mountainsides, and in the higher altitudes, the ptarmigan, timberline sparrow and rosy finch are the most likely to be seen. The Clark's nutcracker is less plentiful than in past years due to the decline in the number of whitebark pines.
Because of the colder climate, ectothermic reptiles are all but absent, with two species of garter snakes and the western painted turtle being the only three reptile species proven to exist.[76] Similarly, only six species of amphibians are documented, although those species exist in large numbers. After a forest fire in 2001, a few park roads were temporarily closed the following year to allow thousands of western toads to migrate to other areas.
A total of 23 species of fish reside in park waters and native game fish species found in the lakes and streams include the westslope cutthroat trout, northern pike, mountain whitefish, kokanee salmon and Arctic grayling. Glacier is also home to the threatened bull trout, which is illegal to possess and must be returned to the water if caught inadvertently. Introduction in previous decades of lake trout and other non-native fish species has greatly impacted some native fish populations, especially the bull trout and west slope cutthroat trout.
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