The 170,000-acre Bering Sea Unit of the Alaska Maritime National Wildlife Refuge includes about 25 islands and headlands in the Norton Sound, the seabird and seal rookeries on the Pribilof Islands, Hagemeister Island near the coast west of Dillingham, and other smaller islands in the Bering Sea. The Saint Matthew Island Group, consisting of Saint Matthew and small nearby Hall and Pinnacle Islands, has been designated Wilderness. One of the largest seabird concentrations in the North Pacific (3.5 million birds) can be found here in summer, dominated by auklets, common eiders, old-squaws, gulls, murres, and puffins. Geographically, this Wilderness is the most isolated in all of America, a beautiful land formed by volcanic activity, rising more than 1,500 feet above the sea with sheer cliffs and waterfalls dropping dramatically into icy water. The annual average for visiting ships is fewer than one. On Saint Matthew you'll find one of the few colonies of northern fulmars on Earth, and almost the entire world's population of McKay's buntings nest here. Northern sea lions and seals haul out at several places, and walruses climb ashore at one spot on Saint Matthew. Reindeer, once introduced here, have disappeared. Arctic foxes den here, and polar bears, practically wiped out by hunting, wander over from the mainland occasionally on the winter ice pack. Gray whales are often seen offshore, and sometimes an endangered bowhead whale swims by in winter.