Peace-Athabasca Delta. 24/05/82; Alberta; 321,300 ha; 58°42'N 111°08'W. World Heritage Site; National Park. Composed of three river deltas and four large freshwater lakes with rich growths of aquatic vegetation, linked to Lake Athabasca by meandering river channels. Underlain by permafrost, there are expanses of open grass and sedge meadows interspersed with hundreds of perched wetland basins, giving rise to thousands of kilometers of shoreline during spring high water. One of the most important nesting, resting and feeding areas for numerous species of waterbirds in North America. Up to 400,000 birds occur during spring migration, and more than one million occur in the fall. The delta meadows provide grazing for several hundred free-roaming bison, one of 44 other mammals recorded. Ramsar site no. 241. Most recent RIS information: 2001.