Montana Attorney General Tim Fox on Nov. 29 joined 16 other states in a federal lawsuit challenging new endangered species regulations they say exceed federal wildlife agencies’ rule-making authority.

The two rules were finalized by the U.S. Fish and Wildlife Service and the National Marine Fisheries Service in February.

The Endangered Species Act, passed in 1973, allows the federal agencies to create special protections for species determined to be in danger of extinction. The act was later amended to require the designation of critical habitat, defined as areas containing features essential to the conservation of those species.

The designation limits the land-disturbing activities that can occur within those boundaries. In Northwest Montana, those areas deemed critical for the recovery of grizzly bears, bull trout and other federally listed species frequently require extra considerations and mitigation measures for proposed logging and construction projects.

The states’ lawsuit alleges that the new rule gives the federal government the ability “to exercise virtually unlimited power to declare land and water critical habitat for endangered and threatened species,” regardless of whether the species occupied those areas at the time they were listed.

In its Feb. 11 entry in the Federal Register, the Fish and Wildlife Service stated that the revisions “avoid introducing previously undefined terms without changing the meaning of the proposed definition.”

The other rule changed the definition of “destruction or adverse modification” of critical habitat under the Endangered Species Act. The lawsuit claims that the change in wording would extend the federal authority to activities “that might prevent currently non-habitable areas from developing into habitat.”

Fox and the other state attorneys general are asking the U.S. District Court in Southern Alabama to vacate the new rules and enjoin the government from enforcing them.

Reporter Sam Wilson can be reached at 758-4407 or by email at swilson@dailyinterlake.com.