"We believe our decision is a good balance and will allow companies to explore this intriguing frontier area while still protecting the resources important to the coastal residents," Luthi said.
Global Warming
Miller and Brendan Cummings of the Center for Biological Diversity said the MMS ignored dangers to animals and birds if an oil spill were to occur.
"No one yet has figured out how to clean up a spill in broken ice, so they just stick their head in the sand and pretend it won't happen," Cummings said.
He also said the agency's environmental assessment ignored changes brought by global warming.
The Chukchi Sea, he said, is the nation's most important habitat for Pacific walrus. The lease sale assumes a stable walrus population, ignoring developments of 2007.
Unlike seals, walruses cannot swim indefinitely and must "haul out" on ice or land to rest. In late summer, thousands of animals hauled out on the northwest Alaska coast for several months because their usual platform for foraging, sea ice, receded far beyond the relatively shallow continental shelf to waters too deep for walrus to dive for food.
On the Russian side of the Chukchi Sea, biologists recorded herds gathering on shore instead of the pack ice, including one group of up to 40,000 animals at Point Shmidt, a spot that had not been used by walruses as a haul-out for a century.
Russian biologists estimate that 3,000 to 4,000 mostly young animals were crushed in stampedes when polar bears, hunters, or low-flying aircraft startled walruses and sent them rushing to the safety of the sea. (See story.)
"It doesn't address the reality that things are happening rapidly with walrus and we need to be very, very careful in what we do," Cummings said of the lease plan.
Polar Bears
The Chukchi Sea also is home to one of two U.S. polar bear populations. The U.S. Fish and Wildlife Service is days away from deciding whether polar bears should be declared threatened because of global warming and its effect on the animal's primary habitat, sea ice.
"The chances for the continued survival of this icon of the Arctic will be greatly diminished if its last remaining critical habitat is turned into a vast oil and gas field," said Margaret Williams, managing director of conservation group WWF's Kamchatka and Bering Sea Program.
Polar bears spend most of their lives on sea ice. They use sea ice to hunt their primary prey, ringed seals. In Alaska, females use sea ice to den or to reach denning areas on land.
Arctic sea ice last summer plummeted to the lowest levels since satellite measurements began in 1979, according to the National Snow and Ice Data Center at the University of Colorado. (See story.)
The sale area will not include near-shore waters, which are about 25 to 50 miles (40 to 80 kilometers) from the coast, Luthi said. That near-shore buffer is used by bowhead and beluga whales, other marine mammals, and marine birds migrating north in the spring, Luthi said, as well as subsistence hunters from coastal villages.
(Related story: Rare Bowhead Whales Can Live to Nearly 200, Eye Tissue Reveals [July 13, 2006])
Cummings said the agency used inadequate standards for assessing the effect of sound from seismic and drilling activity. It also failed to take into account recent sightings of endangered fin and humpback whales in the Chukchi Sea, he said.
"The buffer may put activities out of sight from land but it certainly doesn't shield the land from an oil spill," he said.
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