The Arctic Coastal Plain of Alaska (Region 2*) is a 60,000 km2 area bounded on the north and west by the Arctic Ocean and stretching eastward to the international boundary with the Yukon Territory (Gallant et al. 1995). This poorly drained, treeless coastal plain rises gradually from sea level to the adjacent foothills and then abruptly into the glaciated Brooks Mountain Range. These regions have an arctic climate and are underlain by permafrost. The poor surface drainage results in wet tundra habitats that are dominated by mosses and herbaceous sedges and grasses on the coastal plain, and numerous thaw lakes and wetlands are present. A high density of wetlands characterizes the Arctic Coastal Plain. Between Barrow and Prudhoe Bay some 42 to 86% of several areas were covered by water (Derksen et al. 1981), and lake and marsh coverage has been estimated as 50% (Hussey and Michelson 1966). Many of the shallow thaw-lake wetlands that are of greatest value to breeding waterfowl are most abundant near the Beaufort Sea coast (Derksen et al. 1981) and pond density declines east of Prudhoe Bay.
The Arctic Coastal Plain contains one of the largest and most stable collections of wetlands in North America (Wellein and Lumsden 1964). In spring, water from rapidly melting snow flows over frozen surfaces and fills the numerous shallow thaw lakes and ponds, streams, and rivers (Irving 1972). Alternating processes of freezing, thawing, and water movement enlarge and deepen the basins. As the basins enlarge, breaching of shorelines occurs, resulting in fusion or drainage (Bergman et al. 1977). The distribution of vegetation communities is strongly related to microtopographic features that affect soil drainage. Tussock tundra and beaded streams dominate the foothills of the Brooks Range. Alpine communities dominate vegetation in the mountains.
*Region 2 - NABCI Bird Conservation Region 3. This report covers Alaska only as DU has been engaged only minimally in conservation work in Canada’s high Arctic . For the time horizon of this plan, DU’s work in the region will consist only of activities in support of the Arctic Goose Joint Venture or the Sea Duck Joint Venture of the North American Waterfowl Management Plan.
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