Wildlife advocates have asked a federal court to force the government to come up with a recovery plan for Canada lynx 13 years after the snow-loving wild cats were declared a threatened species.

A lawsuit filed Thursday alleges the long delay by the U.S. Fish and Wildlife Service violates federal law.

Four environmental groups want the U.S. District Court in Montana to set a date for the agency to adopt a "road map" that would detail what's needed for lynx to recover.

A Fish and Wildlife spokesman declined comment on the lawsuit.

It's unknown how many lynx survive in the U.S. They are rarely seen across a 14-state range that includes portions of the Northeast, the Rocky Mountains, the western Great Lakes and the Cascade Range of Washington and Oregon.