Endangered Species Law & Policy

On November 21, 2025, the U.S. Fish & Wildlife Service and National Marine Fisheries Service (collectively, the Services) published several proposed rules to revise their regulations implementing certain provisions of the Endangered Species Act (ESA). To a substantial extent, the Services are proposing to return to the regulations put in place by the first Trump administration in its prior rulemakings and thereby undo the changes put in place by the Biden administration in its prior rulemakings. This is the second in a series of blog posts that will briefly describe each proposed rule. The notice states the Services will accept comments on the proposed rules until December 22, 2025. A number of stakeholders have asked the Services to extend the comment deadline. As of this time, the Services have not done so.

In the second of the proposed rules, U.S. Fish & Wildlife Service (FWS) proposes to amend portions of its regulations implementing section 4(b)(2) of the ESA. Section 4(b)(2) requires consideration of the economic impact, the impact on national security, and any other relevant impact of designating any particular area as critical habitat; and authorizes the exclusion of areas from critical habitat if the benefits of excluding the area outweigh the benefits of designating it as critical habitat. An important distinction between the listing and critical habitat provisions in section 4 is that the former requires determinations to be made without consideration of economic impacts whereas the latter requires consideration of economic and other impacts.

The proposed rule “provides the framework for the role of the FWS's consideration of the economic impact, impact on national security, and any other relevant impacts under section 4(b)(2) of the Act in identifying any potential exclusions from designations of critical habitat.” In doing so, it sets forth a process by which FWS would weigh the impacts of excluding and including particular areas when designating critical habitat, which the agency refers to as an exclusion analysis. Like an “effects analysis” conducted under section 7(a)(2) of the ESA, an “exclusion analysis” involves a stepwise process that begins with the threshold issue whether to conduct the analysis and the factors to be considered when conducting the analysis including consideration of economic and other impacts and conservation plans, agreements, or partnerships.