At issue is the state's plan to kill wolves to preserve a caribou herd inside the Alaska Maritime National Wildlife Refuge on Unimak Island, beginning as early as Tuesday.
Last week, the Alaska Department of Fish and Game announced it would begin shooting some wolves on Unimak, the eastern-most island in the Aleutian chain, to protect caribou calving grounds as part of its aerial predator control program.
While the program is in place in at least six locations around Alaska, it would be the first time in recent history that aerial predator control would be used inside a national refuge in Alaska.
The department planned on using two biologists and four pilots to kill wolves.
The feds responded Monday, cautioning the state that killing the wolves without a special use permit would be considered "a trespass on the refuge" and immediately referred to the U.S. attorney.
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The state has interpreted that as federal officials blocking the program. The lawsuit, which names U.S. Fish and Wildlife Service Acting Director Rowan Gould, his agency and Interior Secretary Ken Salazar, seeks a court order allowing the state to kill seven wolves while the litigation continues.
The state announced the lawsuit after federal business hours. Bruce Woods, a spokesman for the federal agency in Alaska, was reached at his home Friday, but said he could not comment because he had not seen the lawsuit.
Caribou are an important subsistence food for approximately 62 people living on the island, but the animal numbers have been declining. In 2002, there were more than 1,200 caribou. Last year, fewer than 300 were counted. The state has an unofficial estimate of up to 30 wolves.
The state says the killing of wolves is imperative to protect this year's caribou calves.
However, the federal agency says it is required by law to follow a certain process. That, Woods told The Associated Press earlier this week, is a process the state is well aware of but apparently doesn't want to wait for.
"We definitely are saying that any significant action conducted on a wildlife refuge in Alaska requires a special use permit by the service," he said.