Denali National Park and Preserve
Denali National Park and Preserve is located in Alaska, in the central area of the Alaska Ranges, and centres on Denali, formerly Mount McKinley, the highest mountain in North America. It is 20,310 feet (6,190.5 m) high, and from base to peak is 18,000 feet (5,500 m) which is the highest vertical relief of any mountain in the world. The preserve, to the west of the park, is distinguished from the park in that sport hunting is permitted, while in the park hunting is prohibited or restricted to subsistence hunting by local residents. The park and the adjacent preserve cover more than 6 million acres (24,500 km²).
The idea of preserving the Denali region as a national park was first mooted in 1906 but did not come to fruition until 1917. It was then referred to as the Mount McKinley National Park, named after the US president of the time. A portion of Denali, excluding the summit, was included in the original park boundary. In 1947 the boundaries were expanded and in 1976 the park was designated an international biosphere reserve. The Denali National Preserve was established as a national monument in 1978 and in 1980 the two were combined under the name of Denali National Park and Preserve. The Denali Wilderness comprises about one third of the national park and includes the high heart of the Alaska Range including Denali itself.
Glaciers cover about 16% of the area, with several around 20 to 30 miles (32 km to 48 km) long. This glacial landscape bears many distinctive features such as cirques. These bowl-shaped hollows in the side of a mountain are created by the erosive force of moving ice and its burden of accumulated rock and debris. During the thaw the ice can melt and create a small lake.
Permafrost exists in parts of Denali. The active layer, or the layer that freezes and thaws seasonally, can be 1 inch (25 cm) to 10 feet (3.0 m) thick, while the permanently frozen layer below can be 30 to 100 feet (9.1 to 30.5 m). On the lower slope of Denali is a stand of white spruce called the Drunken Forest because of the trees’ haphazard stance. The permanently frozen layer has prevented the trees forming a deep root system and when the active layer melts there is little to hold them upright. Generally speaking the area is largely tundra with, according to elevation, a mix of spruce, willow and poplar. Over 450 species of flowering plants can be found in the park including the colourful golden rod, fireweed, lupine, bluebell and gentian. Blueberries and the bitter soap berries thrive providing food for grizzly bears and black bears.
The harsh and unpredictable climate of the Denali is nevertheless home to a wide variety of animals and birds. Besides the bears there are caribou, Dall sheep, Alaskan moose, wolves, coyotes and smaller animals such as hoary marmots, shrews and Arctic ground squirrels. The rivers and surrounding waters are well known to contain plentiful trout and salmon.