Green groups worry how oil drilling may affect whales and seals; feds say any risk is negligible.

THE GIST

Federal officials released a report assessing the risks to marine mammals from drilling in seas north of Alaska.

Shell wants to drill beginning in July 2012. The company still needs federal approval.

Company spokesman Curtis Smith said Shell plans to hire native Alaskans to watch for marine mammals.

Federal officials say oil drilling in the Arctic Ocean will have "a negligible impact" on the region's endangered whales and seals, but conservationists say the report fails to account for the long-term effects of oil development on marine wildlife and ignores lessons from the Gulf of Mexico oil spill.

The National Marine Fisheries Service released a 54-page report assessing the risks to marine mammals from drilling planned for several sites in the Chukchi and Beaufort Seas north of Alaska. Shell wants to drill beginning in July 2012.

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"No injuries or mortalities are anticipated to occur as a result of Shell's proposed Camden Bay exploratory drilling program, and none are proposed to be authorized. Injury, serious injury or mortality could occur if there were a large or very large oil spill. However the likelihood of a spill is extremely remote," stated NMFS' response which was published on the Federal Register.

Agency officials say noise from the ships in the area might divert or disturb some animals, but not enough to qualify as legal definition of a "take" or harassment.

The drilling area is home to the bowhead, gray and beluga whales, as well as the endangered ringed seal, spotted seal, ribbon seal, bearded seal and harbor porpoise.

Conservation groups and some local Alaskan native groups are fighting the Shell plan. They worry drilling will affect tribal hunting of the bowhead whale, and that any spill would be nearly impossible to clean up because of extreme weather, even during the Arctic summer when the water is free of ice.

"Maybe one well isn't such a big problem, but we really lack is an understanding of what the overall development will look like," said Henry Huntington, science director of the Pew Environment Trust's Arctic program. "NMFS may be right in looking at a narrow case of one summer's exploration wells, but what comes next?"

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He noted that a report earlier this year by the U.S. Geological Survey found gaps in the science of how to measure the effects of the underwater noise from oil drilling on marine mammals that use acoustic signals to communicate with each other and find their prey.

Huntington also blasted the report's assessment of the risk of a spill.

"In Prince William Sound (site of the Exxon Valdez disaster), only one thing went wrong," Huntington said from his office in Eagle River, Alaska. "It was a small likelihood, but 20 years later we are still dealing with the aftermath and there is still oil on the beaches."

"I'm disappointed (NMFS officials) cavalierly dismissed the risks associated with a spill."

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Shell still needs federal approval of its emergency response plan and permits from the U.S. Fish and Wildlife Service that the drilling won't harm polar bears and walruses. Company spokesman Curtis Smith said Shell plans to hire native Alaskans to watch for marine mammals on the drilling ships and spotter planes. It also expects to put response ships ready to go at the drill sites.

Smith said Shell's previous seismic exploration of the Arctic Ocean region from 2006 to 2009 didn't have a measurable effect on the whales.

"We've put out acoustic sub-sea recorders than can detect movement of whales and where they vocalize," Smith said. "We are talking about terabytes of info, and we have a good idea of whale habits."

The fisheries agency is putting the document out for a 30-day public comment period and expects to have a final decision on the permit next spring. Shell must also resolve several lawsuits from conservation groups.

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