ANCHORAGE, Alaska (Reuters) - A planned study of possible new wilderness protections for the Arctic National Wildlife Refuge has sparked a furor in Alaska, where energy companies have long dreamed of tapping oil reserves beneath its vast coastal plain home to herds of migrating animals.
The U.S. Fish and Wildlife Service effort announced this week is part of a sweeping review of a land-management plan for what is the second-largest national wildlife refuge in the United States.
The agency stresses that its work is just starting and that a formal draft is not expected until next year.
But the oil industry and its political allies regard it as a prelude to an attempt to keep the refuge off-limits to energy production for good by formally declaring its remote coastal tundra as wilderness.
"Alaska will not allow the federal government to lock up more land without a fight," Governor Sean Parnell said this week.
The Alaska Wilderness League, for its part, accuses oil companies of trying to destroy a refuge that represents the only place on Alaska's North Slope that is legislatively closed to development.
"The Arctic Refuge is one of the last true wilderness areas left in the United States -- some places are just too special to sacrifice to oil and gas development," said Cindy Shogan, the league's executive director.
Established 50 years ago in the northeast corner of Alaska, ANWR occupies 19.3 million acres (7.8 million hectares), stretching from saltwater marshes of the Beaufort Sea on its northern edge to the spruce, birch and aspen forests in the Brooks Range's southern foothills.
Its wilderness plan was last revised in 1988, eight years after Congress expanded the refuge to its current size and effectively closed all of it to energy development.
The sweeping review is only in its preliminary stages, with a draft plan expected next year, said Bruce Woods, spokesman for the U.S. Fish and Wildlife Service in Alaska.
"We haven't proposed anything for wilderness. We're not nearly ready for that," Woods said on Thursday.
Ultimately, an act of Congress is required to open the coastal plain to oil drilling or designate it as wilderness -- the most protective classification that can be applied on federally owned lands.
But Alaska Senator Lisa Murkowski says the study is "a blatant political move by the administration and clearly violates the promise of no more administrative wilderness designations in Alaska."
"This is a waste of time and taxpayer money -- and it's a proposed waste of the oil and natural gas resources that belong to all Americans," she said in a statement.
Conservation groups have their own supporters on Capitol Hill. A group of U.S. senators is proposing to establish formal wilderness designation for the coastal plain, a move that would make oil drilling in the refuge all the more remote.
For both sides, the crux of the matter is the 1.5 million-acre (607,000-hectare) coastal plain.
Drilling supporters say it could hold 11 billion barrels of oil or more. Opponents say that narrow coastal section is the biological heart of the refuge because it is the calving grounds for the region's vulnerable caribou herd.
Right now, nearly half of the overall refuge is protected as formal wilderness. No such protections exist for the coastal plain. But Congress has not authorized oil drilling there, either.
Review of the Arctic refuge comes amid similar management rewrites for all of Alaska's 16 national wildlife refuges.
But the initial phase of the management review for the Arctic refuge, launched in the spring, has drawn more than 90,000 public comments, he said. In contrast, reviews for other refuges have elicited dozens or a few hundred public comments.
The last time Congress voted to lift prohibitions on oil development in the Arctic refuge was during Republican control of the U.S. House of Representatives and the Senate in 1996. The measure was vetoed by President Bill Clinton.
Editing by Xavier Briand