The thunderous boom of calving ice can sometimes be heard 20 miles away. The park's wildlife is as varied as its landscape. Mountain goats, moose, bears, wolverines, marmots, and other land mammals have re-established themselves on a thin life zone between marine waters and the icefield's frozen edges. Bald eagles nest in the tops of spruce and hemlock trees. Steller sea lions haul out on rocky islands at the entrances to Aialik and Nuka Bays.
Harbor seals ride the icebergs.
Dall porpoises, sea otters, and gray, humpback, killer, and minke whales ply the fjord waters. Halibut, lingcod, and black bass lurk deep in these waters, through which salmon return for inland spawning runs. Thousands of seabirds, including horned and tufted puffins, black-legged kittiwakes, common murres, and the ubiquitous gulls, seasonally inhabit steep cliffs and rocky shores. Exit Glacier , the remnant of a larger glacier once extending to Resurrection Bay, is one of several rivers of ice flowing off the icefield. Active, yet retreating, it provides the perfect setting to explore.