Environment: Alaska's Speeding Glacier

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The first person to report that something was amiss was Guide Mike Branham, 40, a strapping six-footer who each spring flies a pontoon plane full of bear hunters into a cove on Russell Fjord, in Alaska's southeastern panhandle. This year he discovered that things had changed: Hubbard Glacier was on the move -- at a most unglacial pace of about 40 ft. per day. "We saw the glacier advance like it never had before," says Branham. That was in April. Within weeks, the leading edge of ice had sealed off the fjord at its opening, turning the 32-mile-long inlet into a fast-rising lake and trapping porpoises, harbor seals and the saltwater fish and crabs they live on.

Alarmed, most of the 500 residents of the nearby fishing village of Yakutat gathered in the Alaska Native Brotherhood Hall for a briefing by scientists who have flocked to study what the U.S. Geological Survey has called a "world-class natural event." By last week, waters of the stream-fed fjord, renamed Russell Lake, had risen more than 62 ft., and were still climbing, covering the beaches and then the steep, alder-lined banks.

The immediate danger, explained USGS Glaciologist Larry Mayo, is that the lake, now rising about 1 ft. a day, will spill out of its southern end into the Situk River (see chart), a salmon-spawning stream that is the economic lifeblood of Yakutat. If the lake overflows, the clear Situk could become a destructive torrent of silty water about 20 times its present volume, unfit for salmon and fishermen. "In another 500 to 1,000 years," says Mayo, "Hubbard Glacier could fill Yakutat Bay, as it did in about 1130." Susie Abraham, 85, a silver-haired elder of Yakutat's native Tlingit Indian tribe, is fatalistic. "This place where we sit," she says, "belongs to the great glacier."

The animals trapped in Russell Lake are almost certainly doomed. Freshwater from the mountain streams sits atop the denser salt water, with little mixing. As a result, oxygen, which is replenished at the surface through diffusion, cannot be replaced once it is depleted from the salt water. Fish and crabs might last for a year, but the air-breathing sea mammals that eat them will not. "The seals are exhausted from diving through that extra 50 ft. of freshwater before they can reach salt water and maybe find something to eat," says Marine Biologist Tamra Faris of the National Marine Fisheries Service. On her last flight over the lake in mid-July, Faris counted seven harbor porpoises and three Dall's porpoises; last week the porpoises could be seen cruising back and forth along the glacial dam, searching in vain for a passage back to the sea.