Glacier Bay was completely buried under massive glaciers just 250 years ago. When British explorer Captain George Vancouver first charted this area in 1794, he found a wall of ice almost 20 miles wide along the northern shoreline of Icy Strait.
The ice retreated over the next century, and in 1879, famed naturalist John Muir canoed into the bay and discovered a network of inlets, tidewater glaciers and a vast, rocky, ice-scoured landscape. Muir named many of the features in the bay and returned several times to visit and explore.
Today, the glaciers have retreated almost 80 miles up the bay (or "up bay," as the locals say). Free from the crushing weight of the ice, the land in this area is rising rapidly out of the sea. The rate - one inch per year - is the highest rate of rebound on Earth. Comparisons with maps made on Vancouver's voyage show that the landscape on either side of Glacier Bay has risen 18 to 21 feet in the past 200 years. Logs beached by the tides a few decades ago now sit hundreds of yards from the shoreline, and trees are growing in meadows that were tideflats in the 1950s. The area is literally springing out of the ice age. Mountain goats and black and brown bears were quick to move into the area, but moose just began colonizing this country in the 1960s.
Moose can sometimes be seen on the shorelines. Most of the 350 to 400 moose in the area migrate seasonally between distinct summer and winter ranges. They winter in the flat, forest-and-muskeg forelands around the community of Gustavus, browsing on willows. In March, about a quarter of the population swims to the Beardslee Islands in Glacier Bay. The moose spend the summer on these low-lying islands feeding and raising their calves, moose-paddling between the islands. Other moose spend their summers high up in the rugged alpine terrain of Excursion Ridge east of Gustavus.
Brown bears are good swimmers as well. Although they are sometimes seen in the water, they're usually sighted foraging on the beaches and in the intertidal zone. Coyotes and wolves are present but elusive, but may be heard, especially at night. Furbearing mammals such as mink, river otters, marten, weasels and wolverine also make forays to the beaches. Morning and evening are the best times to look.
Glacier Bay is an outstanding area for birds. Some of North America's most southerly nesting colonies of black-legged kittiwakes and Aleutian terns are in Glacier Bay. Kittiwakes are small, long-lived gulls that can be seen plunge-diving near the face of the tidewater glaciers, feeding on small fish pushed to the surface by upwelling currents.
Kittlitz's murrelets can also be seen feeding near the glaciers. These birds are related to the marbled murrelet but are closely associated with tidewater glaciers and barren, rocky post-glacial landscapes. They are considered to be one of the rarest seabirds in North America, and scientists estimate that about one quarter of the world's population of Kittlitz's murrelets are found in Glacier Bay.
Tufted and horned puffins are oceanic species that nest in Glacier Bay, but are rare elsewhere in Southeast Alaska's inland marine waters. The bay's isolated islands offer refuge from land predators, and large numbers of glaucous-winged gulls nest near the bay's resident guillemots and oystercatchers.
Thousands of Vancouver Canada geese molt in secluded Glacier Bay inlets, and these flightless flocks linger from mid-July through August. Unlike many birds which gradually lose and replace their feathers over the course of a year, geese and most waterfowl molt all their feathers at once, growing a new set of feathers in time for their fall migrations.
Glacier Bay and the Gustavus area are important seasonal stopovers in the spring and fall for migrating sandhill cranes, geese and other waterfowl. In April and September the cranes' rattling, croaking calls can be heard as flocks move through the area.
The most numerous local birds may be the common murre in the winter and the red-necked phalarope in late summer. More than 15,000 of each have been counted in concentrated flocks. Marbled murrelets, scoters, buffleheads, goldeneye and harlequin ducks are also familiar summer residents. Also look for grebes, loons, cormorants, and mergansers. Bald eagles are abundant year-round and nest in the area.
Sea lions inhabit the relatively recently exposed islands in Glacier Bay. A haulout on South Marble Island in the lower bay has been drawing increasing numbers of sea lions in recent years - numbers have grown from about 50 sea lions in the 1980s to about 500 in 2001.
Harbor seals are abundant in the bay, and in May and June they congregate in sheltered areas to pup. Thousands of harbor seals nurture their pups on the floating ice in the upper reaches of the bay in Johns Hopkins Inlet and among the reefs of the Beardslee Islands.
Humpback whales frequent the bay in summer, with peak numbers present in July. Minke whales, relatively rare in the Inside Waters, are sometimes seen in Glacier Bay. Dall's porpoises and harbor porpoises are also found.
Sea otters are a favorite among wildlife watchers in Glacier Bay, and their numbers are increasing in the area. In 1995, just five sea otters were counted in the bay; in 2004, a survey found 2,400 sea otters.