Endangered humpback and fin whales swam hundreds of miles north of their usual habitat this summer in what environmentalists say is another sign of the effects of global warming and the shifting Arctic ecosystem. Humpbacks were spotted over the summer in the Beaufort Sea east of Barrow, the northernmost community in the United States, and last year in the Chukchi Sea, west of the Beaufort and north of the Bering Strait, said Robin Cacy, a spokeswoman for the federal Minerals Management Service.The agency oversees lease sales for offshore petroleum drilling in federal waters, including sales scheduled for 2008 in the Chukchi Sea and 2009 in the Beaufort Sea.Some of the whales were spotted by observers involved with the oil industry, others by observers involved with barge traffic.Cacy also said fin whales were detected this summer by acoustic monitoring in the Chukchi Sea, more than 300 miles north of their normal range. Both humpback and fin whales normally stay south of the Bering Strait in Alaska waters.Environmental groups are calling for more study of the endangered animals' habits before industrial activity is allowed to expand off Alaska's northern shores.No one was expecting humpbacks near the activity connected to Outer Continental Shelf lease sales, said Brad Smith, a protective resources biologist for the National Marine Fisheries Service."We didn't anticipate that they'd been encountered in any of the OCS exploration activity that we're doing this year," Smith said.Minerals service spokesman Gary Strasburg said a sighting of an endangered species in a new area would not mean an immediate change in how the agency regulates petroleum exploration. It will take more time to determine whether the presence of humpbacks is a trend, and if so, for the agency determine the appropriate response, he said.Brendan Cummings, ocean programs director for the environmental group Center for Biological Diversity, said the humpback sightings may indicate a recovering population expanding its range — or desperate animals in search of food.Deborah Williams, a former Department of Interior special assistant for Alaska and now an advocate for finding solutions to climate change, said the presence of humpback and fin whales so far north has significant implications."We now have even more compelling reasons to protect the Arctic Ocean and the species dramatically affected by climate change," she said.Other species that use the Chukchi Sea are behaving differently because of climate change, Cummings said. He cited gray whales seeking new feeding areas, and walrus congregating on Alaska's northwest shore this summer instead of on pack ice that had receded far beyond the continental shelf."It looks like the populations are suffering from it," he said. "All signs point to global warming. That would be the first suspect of why the whales are there."Interior Secretary Dirk Kempthorne in December proposed listing polar bears as threatened under the Endangered Species Act. Environmental groups had filed a petition stating that polar bears could become extinct by the end of the century because their sea ice habitat is melting away due to global warming. A final listing decision is due in January.Sheela McLean, spokeswoman for the National Oceanic and Atmospheric Administration's fisheries service in Juneau, said humpbacks range widely and have been previously spotted on the Russian part of the Chukchi Sea. However, humpbacks are not usually associated with pack ice, so sightings farther north might be shifts in distribution caused by climate change, she said.This year was a record low year for pack ice. The National Snow and Ice Data Center at the University of Colorado at Boulder in September recorded 1.65 million square miles of sea ice. That's 39 percent below the long-term average from 1979 to 2000.Permits issued in 2007 for exposure of marine mammals to noise from seismic activities in the Beaufort and Chukchi seas covered neither humpback nor fin whales, said Smith, the fisheries service biologist. He added, however, that whales including grays and bowheads are covered, and that adding the other species might not increase the conditions placed on exploration. The sensitivity of bowhead whales, which remain close to sea ice and are hunted in limited numbers by Eskimo whalers, is considered equal to or greater than the sensitivity of humpbacks, Smith said. Cummings does not agree with that assessment of humpbacks — or with the government's protective measures in general. "These are animals that are entirely dependent on sound," he said of humpbacks. Permits issued don't take into account the federal government's own research indicating how easily whales can be deflected from their intended paths, Cummings said. The noise could have consequences for whales' feeding behavior, especially mothers migrating with their young. "We don't believe that permits issued to date in the Beaufort Sea comply with the spirit or the letter of the Marine Mammal Protection Act or the Endangered Species Act," Cummings said. Full-grown humpback whales average more than 40 feet long and weigh 25 to 35 tons. Fin whales are longer and more slender, growing to nearly 88 feet — second only to blue whales.
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