On Nov. 21, 2025, the U.S. Fish and Wildlife Service (FWS) released four proposed rules to revise its Endangered Species Act (ESA) implementing regulations, all of which would apply only prospectively. 90 Fed. Reg. 52587, 52592, 52600, 52607. FWS crafted two of the proposed rules jointly with the National Marine Fisheries Service (NMFS), the agency with jurisdiction over endangered and threatened marine species. The proposed changes largely revert back to regulations enacted, or policies put in place, during the first Trump Administration. The ESA states that listing decisions should be based “solely on the basis of the best scientific and commercial data available . . . after conducting a review of the status of the species” and taking into account certain listed factors. 16 U.S.C. § 1533(b)(1)(A). A common theme of the proposed regulations is the extent to which economic effects can be considered. All four proposed rules draw upon, among other executive orders, E.O. Number 14154, “Unleashing American Energy,” which required agencies to identify actions that “impose an undue burden on . . . domestic energy resources” and consider cancelling actions “that conflict with this national objective.” The proposed rule changes also rely upon the Supreme Court’s holding in Loper Bright Enterprises v. Raimondo that statutes have a “best” interpretation that must be honored. 603 U.S. 369, 400 (2024). Loper Bright came out several months after the 2024 versions of the rules promulgated during the Biden administration took effect. 

FWS Proposed Rule to Remove ‘Blanket Rule’ Protections for Newly Listed Threatened Species

FWS would remove the so-called “blanket” rule approach to protecting newly listed, threatened species under section 4(d) of the Act and instead require the Service to adopt species-specific rules that purposely consider both the rule’s conservation and economic impacts for each species that is listed.  90 Fed. Reg. 52587.

• Section 4(d) provides that “[w]henever any species is listed as a threatened species pursuant to subsection (c) of this section, the Secretary shall issue such regulations as he deems necessary and advisable to provide for the conservation of such species.” 16 U.S.C. § 1533(d).
• Section 9 of the ESA prohibits a suite of actions with respect to endangered species, including activities that result in a “take” of individual members of the species. Section 9’s prohibitions do not automatically apply to species that are listed as threatened rather than endangered; in the past, the Service issued blanket rules that automatically extended most of Section 9’s prohibitions to each threatened species immediately after a listing decision, at least as a provisional measure.
• In 2019, during the first Trump administration, FWS removed the blanket rule protections, but in 2024 (during the Biden administration), they were restored. Both versions were challenged in court; the challenge to the 2019 rule was remanded and the cases challenging the 2024 rule remain pending.
• The proposed rule justifies its approach both as the best legal interpretation of the ESA, because “[t]he statutory text, structure, and context make clear that Congress intended for the Service to determine what protections are needed for threatened species on a species-by-species basis” and as “a superior choice from a policy perspective” because “the tailored approach reduces burdens on the Service and regulated entities alike and allows for the Service to better protect threatened species.”
• Under the proposed rule, blanket rules in effect now would continue to apply until species-specific rules are promulgated. In addition, the rule states that the proposed change “also brings the Service in line with the Department of Commerce’s longstanding practice of developing species-specific 4(d) rules.”

FWS Proposed Rule to Change Critical Habitat Designation Considerations

FWS would also amend rules implementing Section 4(b)(2) of the ESA, which governs FWS’ ability to exclude areas from a critical habitat designation to more clearly identify economic and national security factors that the agency must weigh when deciding which areas to exclude from a designation. 90 Fed. Reg. 52592.

• Under Section 4(b)(2) of the ESA, when FWS decides what to designate as critical habitat for a species, the agency must consider economic impacts, impacts on national security, and any other relevant impacts of specifying a particular area as critical habitat. An area may be excluded from critical habitat if the benefits of excluding it outweigh the benefits of including it, provided that the Secretary determines that the exclusion would not result in the extinction of the species.
• The proposed rule states that, in addition to the agency’s discretion to consider a particular area for exclusion unilaterally, another trigger for the exclusion analysis is “when a proponent of excluding the area has presented credible evidence in support of the request.”
• Importantly, the rule not only reverses a policy of presumptively not excluding areas on federal lands from critical habitat designations, but also requires consideration of “the avoidance of the administrative or transactional costs associated with the [Section 7] consultation process as a benefit of exclusion of a particular area of federal land”(emphasis added)— which would seem to always tip the scales in favor of excluding them.
• The proposed rule specifies categories of economic impacts to be considered, including “opportunity costs” in addition to productivity, jobs, and the like.
• The proposed rule also expressly requires the Secretary to consider the impacts of including or excluding an area from a critical habitat designation on any conservation plan, agreement, or partnership that covers the same area.

FWS and NMFS Proposed Rule to Change Listing and Delisting Procedures

Both the NMFS and FWS propose to revise the regulations governing criteria and procedures for listing, reclassifying, and delisting threatened and endangered species and designating critical habitat. 90 Fed. Reg. 52607. The proposed changes:

• Remove the phrase “without reference to possible economic or other impacts of such determination,’’ when making classification determinations, which the rule states would better align with the statutory text.
• Specify that unoccupied areas may only be deemed critical habitat when (1) “a critical habitat designation limited to geographical areas occupied would be inadequate to ensure” the species’ conservation, and (2) the Secretary specifically determines “there is reasonable certainty both that the area will contribute to the conservation of the species and that the area contains one or more of those physical or biological features essential to conservation of the species.”
• Replace the current definition of “foreseeable future” (used to determine the time frame in which a species is likely to become “in danger of extinction,” 16 U.S.C. § 1533(b)(1)(B)(ii)), with the more restrictive 2019 version to make the definition more clearly “bounded by what is foreseeable based on the best scientific and commercial data available.”
• Clarify that the standard for delisting is the same as the standard for listing (i.e., that the species does not meet the definition of an endangered or threatened species).

FWS and NMFS Proposed Rule to Modify Interagency Section 7 Consultation Procedures

Both agencies further propose amending certain provisions that relate to the agencies’ Section 7 consultation (aka interagency cooperation) requirements, and removing the “offset” provisions of the 2024 rule, which authorized imposing “measures implemented inside or outside of the action area that avoid, reduce, or offset the impact of incidental take” as a condition of granting at take permit. 50 C.F.R. § 402.14 (i)(2). The agencies also propose changes to the definitions of “environmental baseline” and “reasonably certain to occur” to exclude impacts the agency has no ability to prevent or are speculative. The proposed changes would be consistent with regulatory provisions promulgated in 2019 during the first Trump administration, and include language that would:

• Change the definition of “environmental baseline,” the comparator for determining the effects of the proposed action that triggered the Section 7 consultation, to clarify that only the effects of discretionary agency actions need to be considered.
• Change the definition of “effects of the action” to list non-exclusive factors that agencies should consider to determine when effects are or are not reasonably certain to occur.  In addition to the factors listed in 2019, the regulations include whether “the consequences would occur regardless of whether the proposed action goes forward” and, incorporating “trans-substantive” proximate cause principles announced in the Supreme Court’s 2025 National Environmental Policy Act decision, Seven County Infrastructure Coal. v. Eagle County, Colorado, 605 U.S. 168 (2025), on whether “the agency has no ability to prevent the consequence due to its limited statutory authority.”
• Require the use of “clear and substantial information” to support a finding that a given effect is “reasonably certain to occur.” This requirement would prevent the agencies from using the so-called “precautionary principle, in which an agency gives the “benefit of the doubt” to a species in the face of uncertainty. See generally Maine Lobstermen’s Ass’n v. Nat’l Marine Fisheries Serv., 70 F.4th 582, 599–600 (D.C. Cir. 2023).
• Rescind parts of the 2024 rule that referred to offsetting measures in reasonable and prudent measures adopted as part of an incidental take statement, finding that “offset” and “mitigation” are not sufficiently rooted in Section 7’s language. 16 U.S.C. § 1536(b)(4).

Next Steps

The proposed rules will be open for public comment until Dec. 22, 2025. If finalized, the rules would have important consequences for stakeholders engaged in activities that trigger Section 7 consultation among federal agencies, may result in “take” under ESA Section 9, or are covered by a permit conditioned on offsetting reasonable and prudent measures. Members of potentially regulated industries should carefully evaluate how the proposed changes might affect them and consider submitting comments to inform decision-makers and preserve their rights.