Parc national Wood Buffalo

Brève description

Valeur exceptionnelle

Le Parc national Wood Buffalo est un exemple exceptionnel de phénomènes écologiques et biologiques permanents, qui comprend certaines des plus vastes et des dernières prairies d’herbe et de laîche vierges en Amérique du Nord, et abrite le plus gros troupeau de bisons des bois du monde, une espèce menacée. Les vastes étendues de forêt boréale constituent également un habitat vital pour une grande diversité d’autres espèces, dont la grue blanche, en danger de disparition. L’évolution continue d’un vaste delta intérieur d’eau douce, des plaines salées et de karsts gypseux ajoute aux valeurs exceptionnelles du parc.

Critères

(vii) Les grandes concentrations d’oiseaux migrateurs sauvages ont une importance mondiale et les phénomènes naturels rares et incomparables que constituent le grand delta intérieur, les plaines salées et les karsts gypseux ont également une valeur sur le plan international.

(ix) Wood Buffalo est l’exemple le plus complet sur le plan écologique et le plus important de tout l’écosystème des Grandes plaines et prairies boréales vierges d’Amérique du Nord, le seul lieu où le rapport prédateur-proie entre le loup et le bison des bois s’est maintenu, sans s’interrompre, au fil du temps.

(x) Wood Buffalo contient le seul habitat de reproduction au monde de la grue blanche, espèce menacée qui a été sauvée de l’extinction grâce à une gestion attentive du petit nombre de couples reproducteurs dans le parc. La superficie du parc (4,5 millions d’hectares), les écosystèmes complets et la protection sont essentiels à la conservation de la grue blanche sur le site.

Description longue

Situated on the Northern Boreal Plains in the north-central region of Canada, Wood Buffalo comprises a vast wilderness area (44,807 km² ) which is home to North America's largest population of wild bison. It is also the natural nesting place of the whooping crane. Another of the park's attractions is the world's largest inland delta, located at the mouth of the Peace and Athabasca rivers.

The park has four main landscape featues: a glacially eroded plateau; glaciated plains; a major freshwater delta formed by three major rivers; and alluvial river lowlands. The lowlands and floodplains of Peace, Athabasca and Slave rivers and the delta in Lake Athabasca exhibit classic fluvial landforms, with a complex series of meander scars, oxbow lakes and former river terraces, and good examples of birds-foot delta development. During dry periods, the mudflats of one plain are dominated by mineral salts. These salt plains are unique in Canada.

Vegetation is typical of the boreal forest zone with white spruce, black spruce, jack pine and tamarack predominant. Many watercourses have stands of balsam poplar and some upland has almost pure stands of aspen. Extensive stands of white spruce forests cover the banks of Peace, Athabasca and Birch rivers. The upper surface of the plateau is about 1,500 m above the rest of the park and supports a spruce-willow-birch upland tundra community. Some areas of prairie occur.

Shrublands of willow and alder occur where wet marsh soils meet drier forest soils. There is also extensive muskeg in the west and north of the park, an association of black spruce, sphagnum moss and northern heath plants.

The park contains the largest undisturbed grass and sedge meadows in North America. The park was created specifically to protect North American bison, one of the largest free-roaming, self-regulating herds in existence, and consisting of a cross between 'wood' bison and 'plains' bison.

This is one of a few sites where the predator-prey relationship between wolves and bison still exists. A total of 46 other mammal species have been recorded including black bear, woodland caribou, Arctic fox, moose, grey wolf, lynx, snowshoe hare, muskrat, beaver and mink. Occasionally animals more common to southern Canada are seen, such as red fox, porcupine and white-tailed deer. The caves of karstlands provide essential hibernation sites for bats.

A total of 227 bird species have been recorded which include great grey owl and snowy owl, willow ptarmigan, redpoll crossbill and boreal chickadee. This is the only breeding site of whooping crane; peregrine falcon and bald eagle also breed within the park. The Peace-Athabasca Delta is an important area for migrant waterfowl including snow geese, white-fronted geese and Canada geese, whistling swan, diver, all seven species of North American grebe and species of duck.

Reptiles and amphibians are severely limited in numbers, but Canadian toad, leopard frog and red-sided garter snake reach their northern limits here. Boreal chorus frog and wood frog are also found in aquatic habitats. The fish fauna has been poorly studied, although there are a wide variety of aquatic habitats. 36 species have been recorded to date, four of them introduced.

Description historique

1922 (as 2,600,OOOha), expanded in 1926. Includes much of the Whooping Crane Summer Range and the Peace-Athabaska Delta (Wood Buffalo National Park section), both designated as Ramsar sites ln May 1982.