Wolves back in hunters' sights after US government removes their protection

Permits for wolf hunts are selling briskly in the US state of Idaho, after most wolves in the Northern Rockies were officially struck from the endangered species list in an unprecedented removal of protection by Congress.

Now the roughly 1,200 wolves in Idaho and Montana will be managed by state wildlife agencies. The hunting "tags" cost $11.95 (£7.25) and will cover an expected 220 of the state's 700 wolves. Montana is likely to set a similar quota for its 550 wolves. The federal government has also delisted wolves in Oregon, Washington and Utah. Congress ordered the delisting – and banned intervention by courts – in a provision tucked into a federal budget bill approved after much political bartering on 14 April.

It was the first time in the decades-long history of the Endangered Species Act that an animal was delisted by legislation rather than by scientific review.

That followed a federal court ruling in August that upheld conservationists' legal challenges to the government's 2009 delisting of wolves in Idaho and Montana and returned those populations to the endangered species list.

On Thursday, conservation groups filed lawsuits in the US District Court in Montana, trying to restore federal safeguards to wolves. The groups say Congress overstepped its bounds and violated the constitutional separation of powers by intervening in the ongoing legal case and by exempting the delisting provision from judicial review.

Noah Greenwald, endangered species director for the Centre for Biological Diversity, called the congressional provision a "terrible precedent", adding: "It opens the door for any political [body] who doesn't like an endangered species asking Congress to delist it."

Wolves in the West have been blamed for preying on livestock and big game animals, provoking outcries from the region's powerful ranching and sporting constituencies. Environmentalists say they fear wholesale killing in the absence of federal protections.