A northern Idaho county and a snowmobile group sued the U.S. Department of Interior in federal court, the latest step in their bid to have Endangered Species Act protections lifted from rare woodland caribou that roam the U.S-Canadian border region.

Bonner County and the Idaho State Snowmobile Association filed their complaint Thursday in U.S. District Court.

They're being represented by the Pacific Legal Foundation, a conservative legal group.

Their complaint contends U.S. Interior Secretary Ken Salazar has failed to act on their petition lodged earlier this year contending the caribou were improperly given ESA protections starting in 1983.

They want Salazar to make a decision on the petition - and to pay for their lawsuit.

Four caribou were counted south of the Canadian border during an aerial census last winter.