The federal government is not doing enough to protect Canada lynx, a threatened species that lives in the forests of northern Maine and at least two other states, a dozen environmental groups allege in a lawsuit filed last week in U.S. District Court in Washington, D.C.

The groups, including the Conservation Action Project and Defenders of Wildlife, contend that the U.S. Fish and Wildlife Service has ignored threats to lynx in many places, including logging and ski areas, and has not done enough to protect habitat for the small wild cats. Many of the same groups had threatened to sue before the cats were classified in March as “threatened” under the federal Endangered Species Act.

The cats, which have large feet to propel them across deep snow, were only confirmed to be living in Maine last year when a pair of kittens was found west of the Allagash Wilderness Waterway.

Canada lynx, which weigh between 20 and 25 pounds, are known to live in three states – Maine, Montana and Washington. The cats are plentiful in Canada, where it is still legal to hunt them.

At the time of the “threatened” listing in March, which is effective throughout the country, federal and industry officials said the animals and logging were compatible. Lynx dens have been found in the slash left behind after logging operations.

Still, environmentalists don’t think the animals are being protected adequately, especially in the Northeast.

“The listing that is in place is not protecting the lynx,” said David Carle, executive director of the Conservation Action Project in New Hampshire.

He said the practice of thinning small trees lowers the forest’s rodent population, which can negatively affect lynx.

“We’re not opposed to logging, but we need to do logging with concern for the native creatures,” Carle said Monday.

Paul Nickerson, the endangered species coordinator for the Northeast region of the U.S. Fish and Wildlife Service, said the lawsuit raises “silly allegations.”

“The lynx are doing fine,” he said. “We have no evidence that logging affects the lynx in Maine.”

His agency and the Maine Department of Inland Fisheries and Wildlife are in the midst of a study of lynx in the state. They hope to learn their numbers and habits so a protection plan can be better tailored to meet the animals’ needs, said Mark Latti, an IF&W spokesman.

The agency has banned coyote snaring and trapping in areas where lynx are known to live. The cats have been listed as a protected species by the state since 1967 so it has been illegal to hunt or trap them.

“We feel we’re doing all we can,” Latti said.

This summer a lynx was hit by two vehicles and killed in Portage.

Gov. Angus King, in his opposition to the recent listing of Atlantic salmon, argued that an endangered species listing opens the door to such lawsuits. “It confirms my worst fears,” he said Monday.

“This is why you resist an endangered species listing,” King said.

Earlier this month, the state filed a lawsuit in federal court challenging the decision of two federal fisheries agencies to list Atlantic salmon in eight Maine rivers as endangered.