Eighteen states have filed a lawsuit against the federal government over Final Rules that expand the definition of “critical habitat” to include areas that are currently unoccupied by any threatened or endangered species. The Final Rules, Listing Endangered and Threatened Species and Designating Critical Habitat, which were published in the Federal Register on February 11 and went into effect March 14, expand the definition of “critical habitat” to include areas in which “species presence or habitats are ephemeral in nature, [or] species presence is difficult to establish through surveys (e.g. when a plant’s ‘presence’ is sometimes limited to a seed...