ICP Detail: Arctic Plains Mountains - Alaska

Arctic Plains and Mountains - Alaska Region 2*

The Arctic Coastal Plain of Alaska 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.

Importance to Waterfowl

Intensive fieldwork at Storkersen Point, near Prudhoe Bay, revealed 18 species of waterfowl, including seven species that nested (Bergman et al. 1977). In a broader study of the National Petroleum Reserve Area (NPR-A), 19 species of swans, geese, and ducks were identified, including 11 breeding species (Derksen et al. 1981) which included tundra swan, black brant, white-fronted goose, lesser snow goose, northern pintail, green-winged teal, greater scaup, king eider, spectacled eider, long-tailed duck, and white-winged scoter. Avifaunal records of the Beaufort Sea area for both Alaska and Canada reveal some 37 swan, goose, and duck species (Johnson and Herter 1989). King (1990) estimated over 1 million waterfowl on the Arctic Coastal Plain, including over 400,000 dabbling ducks, over 60,000 scaup, over 540,000 sea ducks, over 160,000 geese, and over 10,000 tundra swans. The dominant species included long-tailed ducks (>495,000), northern pintails (>390,000), and white-fronted geese (>145,000). The highest density of breeding pairs in 1989-91 (Conant and Dau 1991) included northern pintails at 10.4 pairs/mi2, canvasback (6.9), American wigeon (4.9), and long-tailed duck (3.8).

The Arctic Coastal Plain is also a critically important area for migration and molting. Periodic drought displacement of northern pintail to this region is dramatic, where density of birds may reach over 45/km2, and as much as 15% of the continental population may be found in the Arctic Coastal Plain (Derksen and Eldridge 1980). Although pintails are abundant on the coastal plain, especially associated with shallow Arctophila wetlands, sex ratios are heavily skewed toward males, and most are probably nonbreeders. The king eider migration alone has been estimated at over one million birds passing Point Barrow (King and Lensink 1971). This area has a significant, but declining population of spectacled and Steller's eiders, both federally threatened species. This region, combined with western Alaska, the Alaska Peninsula, Kodiak Island, and the Aleutians, represents the most important area for sea ducks in the world. Molting geese regularly use the approximately 100 lakes around Teshekpuk Lake. In 1990 there were 23,395 brant, 12,233 Canada geese, 6,619 white-fronted geese, and 154 lesser snow geese, not including young (King 1990).

Importance to Other Birds

In addition to waterfowl, the interspersed tundra habitats are used by caribou, brown bear, polar bear, foxes, lemmings, ptarmigan, passerines, raptors, and shorebirds. Four loon species (common, arctic, yellow-billed and red-throated) use this arctic wetland assemblage, and more than 30 shorebird species have been recorded. Among the most common breeding shorebirds are red and northern phalaropes, pectoral sandpiper, and dunlin (Derksen et al. 1981). All three jaeger species are present, as are Sabine's gull and arctic tern. The most common passerine breeder is lapland longspur. In the Brooks Range, foothill areas are important for all scoters, especially black scoters, while riparian associated shorebird species include wandering tattler, semipalmated sandpiper, and spotted sandpiper. The Arctic Coastal Plain is far more important to continental waterbird populations than is the Brooks Range.

The vast majority of the Arctic Coastal Plain is in public ownership. The NPR-A includes over 9,474,000 ha and is managed by the Bureau of Land Management, while the 607,000 ha of eastern plain is known as the "1002 Lands" and is managed by the USFWS as part of the Arctic NWR. The Prudhoe Bay/Deadhorse area is privately owned and has undergone considerable development. Most of the Brooks Range is in protected status under the National Park System (NPS) and includes Noatak NP, Gates of the Arctic NP and Kobuk Valley NP.

Wetland degradation in these regions is principally from petroleum development of the North Slope, transportation systems (roads, pipelines, airports), and urban development. More than 800 exploratory oil and gas wells have been drilled on the Arctic Coastal Plain. Approximately 8,100 ha of wetlands have been directly degraded through petroleum development and secondary effects, such as flooding and thermal erosion of permafrost has had additional impacts. Petroleum development on the Arctic Coastal Plain results in much more extensive disturbance of wetlands than in more southerly locations, because it requires fill material, over permafrost, to construct infrastructure. This infrastructure, which consists of drill pads, storage areas, transportation facilities, gravel mines, and housing, alters terrain, disrupts natural drainage patterns, and may modify fish and wildlife habitat. The existing infrastructure for oil and gas operations in the Prudhoe Bay - Kuparuk complex is spread over more than 1,287 ha2 of tundra. Nevertheless, the amount of wetland area affected is relatively small. Winter activity will reduce human disturbance impacts on waterbirds; however, certain key areas (e.g., Teshekpuk Lake region) may need refuge status.

Current Conservation Programs

In partnership with the Bureau of Land Management (BLM), USFWS, and North Slope Borough, DU completed a digital landcover map of the entire 9.4 million ha of the NPR-A (Kempka et al. 1995). Because of the immense size of the project area and limited field access, this effort was phased over three field seasons. The products from this effort have been used extensively in planning potential petroleum leases for the future. In addition to the landcover classification, correlations among mapped landcover classes and point locations for seven waterfowl species was conducted (Morton et al. 1998). Results from logistic regression model development suggest that the distribution of spectacled eider seem to coincide with high concentrations of Flooded Tundra, (Carex aquatilis), (Arctophila fulva) and smaller water bodies, and to be negatively associated with concentrations of Tussock Tundra, Dwarf Shrub, Ice, and large water bodies.




* 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.