Western Alaska (Region 1*) consists of the Subarctic Coastal Plain from Kotzebue Sound and Seward Peninsula to the Bristol Bay lowlands. The coastline includes the Norton Sound, Bering Sea islands, Bristol Bay, and the Yukon-Kuskokwim Delta which is the largest riverine delta in western North America. The Norton Sound contains 16 lagoons (over 88,000 ha), 2 large tidal river mouths (over 2,100 ha), 49 rivers, and 386 streams. The four Bering Sea islands (St. Lawrence, Nunivak, St. Matthew and the Pribilofs) contain 37 lagoons (over 37,000 ha), 40 rivers, and nearly 400 streams. Bristol Bay (including the Alaska Peninsula) contains 31 lagoons (over 206,000 ha), 3 large tidal river mouths (nearly 16,000 ha), 56 rivers, and 749 streams. The Yukon-Kuskokwim Delta contains 13 lagoons (over 103,000 ha), 22 large tidal river mouths (over 141,000 ha), 171 rivers, and nearly 2,100 streams. Overall, this region contains over 9.7 million ha of salt water less than 18 m in depth, 10,881 km of shoreline, 97 lagoons with an area greater than 435,000 ha, 27 large tidal river mouths with an area nearly 160,000 ha, some 534,000 ha of unvegetated intertidal zone, over 1 million ha of vegetated intertidal zone, 316 rivers, and over 3,600 streams (King and Dau 1981). The wet and moist tundra of the Subarctic Coastal Plain is dominated by sedges, grasses, and mosses, with numerous lakes and ponds.
The Yukon-Kuskokwim Delta is one of the most important waterbird areas on the continent. Within 60 km of the coast this area is directly impacted by tidal action, but annual precipitation, river action, and permafrost play significant roles in wetland function. Wet meadows and sedge marshes are interspersed throughout the volcanic Aleutian Islands. The Alaska Peninsula is a 48,000 km2 area extending from Becharof Lake to Dutch Harbor and is dominated by dwarf scrub, moss/lichen, tall riparian, and sedge wetlands. The peninsula has a coastline longer than that of the conterminous United States, and includes Izembek Lagoon which contains 34,000 ha of eelgrass (one of the largest eelgrass beds in the world).
*Region 1 - NABCI Bird Conservation Regions 1 & 2