Parc international de la paix Waterton-Glacier

Brève description

Valeur exceptionnelle

Le Parc international de la paix Waterton-Glacier présente un climat distinctif, un cadre physiographique, une mise en contact des biomes de montagne et de prairie et une ligne de partage des eaux tri-océanique. C’est une aire dotée de valeurs panoramiques remarquables, avec une flore et une faune abondantes et variées.

Critères

(vii) Les deux Parcs nationaux ont été désignés à l’origine par leurs nations respectives en raison du décor montagneux superbe, du relief topographique élevé, du paysage glaciaire et de la faune et de la flore abondamment diversifiées.

(ix) Le bien occupe une place centrale dans la cordillère occidentale de l’Amérique du Nord, ce qui a donné lieu à l’évolution de communautés végétales et à des complexes écologiques qui ne se retrouvent nulle part ailleurs dans le monde. Les régimes climatiques maritimes non entravés par les chaînes de montagnes au nord et au sud permettent aux plantes et aux animaux caractéristiques du Pacifique nord-ouest de s’étendre dans le parc jusqu’à la ligne continentale de partage des eaux. A l’est, les communautés de prairie se blottissent contre les montagnes sans le moindre contrefort, produisant un développement de l’interface entre communautés de prairie, montagnardes et alpines. Le Parc international de la paix comprend les sources de trois grands bassins fluviaux drainant des biomes remarquablement différents vers plusieurs océans. L’importance biogéographique de cette ligne de partage tri-océanique est accrue par les nombreuses liaisons végétalisées entre les sources. Le résultat net est la création d’un ensemble unique et d’une grande diversité de flore et de faune concentrée dans un espace restreint.

Description longue

The park is situated in the extreme south-west of the Province of Alberta, along the eastern slopes of the Continental Divide and at the western margin of the Canadian Great Plains region; it includes prairie, lakes and mountains.

Local relief is dominated by the 2,500 m peaks of the Border and Clark Ranges, which are generally less rugged than their Glacier National Park counterparts. The park is centred on a long, narrow 'glacier trough' lake.

The most immediately obvious feature of the park is the sudden transition from prairie to mountain landscape; a contrast which is emphasized by the virtual absence of intervening foothills.

The dominant landforms of the park are of glacial origin; typical of both mountain and continental glaciations. The mountain valleys and rock basins were shaped by glacial erosion, whereas the rolling grasslands are a result of glacial deposition.

The joint Waterton-Glacier properties contain a stratigraphic record spanning more than 1,250 million years of sedimentary and tectonic evolution.

The Waterton-Glacier area is at the centre of what has been described as a major floristic discontinuity which occurs at about 50° N latitude and which divides the southern ranges of the Rocky Mountains from the more northerly ranges. The prevalence of a maritime climate results in many species occurring which are closely related to the flora of the far west.

Five large ecoregions are found within Waterton-Glacier National Parks; these are alpine tundra, subalpine forest, montane forest, aspen parkland and fescue grassland.

The alpine tundra ecoregion is found above 2,100 m on the west slope and 1,800 m on the east. Arctic-alpine tundra vegetation covers much of the terrain, typical species including drays tundra and dwarf alpine poppy.

The subalpine forest ecoregion is the single-most vegetation cover in the park. A strong boreal element is typical of this ecoregion, characterized by such species as dwarf birch and fireweed.

The montane ecoregion (Canadian zone) occurs at low to mid elevations, but is largely restricted to the dry foothills and major river valleys of the eastern slopes.

The aspen parkland ecoregion serves as a transition belt between the prairie grasslands and the coniferous forest zone, with dominant tree species being trembling aspen and balsam poplar. Commonly known as 'bunchgrass prairie', the fescue grasslands ecoregion is typified by the festuca/danthonia grass association. The park is noted for an abundance of wildlife and a wide diversity of habitats. Investigations have listed 61 species of mammals, 241 species of bird, and 20 species of fish; reptiles and amphibians have not been extensively studied. Carnivores include grey wolf, coyote, cougar, American black bear and mink. There is also a self-sustaining population of more than 200 grizzly bear in the Waterton-Glacier complex. Other ungulates include mule deer, white-tailed deer, moose, bison, mountain goat and bighorn sheep, the last two being indigenous to the region. Rodents include beaver and muskrat.

Waterton is located on the margin of two major avian migratory routes; the Central and Pacific flyways overlap here, and the marsh and lake areas of the park are used extensively as staging areas. Both the bald eagle and peregrine falcon pass through the area.

Fish fauna includes lake whitefish, cut-throat trout, rainbow trout, lake trout, bull trout Salvelinus and Arctic grayling.