Comments on the proposed rule regarding rescission of the definition of “Harm” under the Endangered Species Act

SUMMARY

The Animal Law Committee submitted a public comment strongly opposing a proposed rule by the U.S. Fish and Wildlife Service and National Marine Fisheries Service to narrow the definition of “harm” under the Endangered Species Act (ESA). The proposed change would exclude habitat destruction from the definition, limiting the law’s ability to protect endangered species from indirect threats.

Opponents argue this rollback contradicts decades of legal precedent, undermines Congressional intent, and weakens essential environmental safeguards. The comment cites key court decisions and scientific consensus showing that habitat loss is the leading cause of species decline. It warns that the new rule would fast-track development projects without proper environmental oversight, threatening ecosystems and wildlife survival. The comment urges the agencies to uphold the current, broader definition of “harm,” which has been instrumental in protecting vulnerable species and their habitats for nearly 50 years.

RULE INFORMATION

FWS-HQ-ES-2025-0034 – U.S. Fish and Wildlife Service and the National Marine Fisheries Service

OUTCOME

Adopted  91 Fed. Reg. 43300 – July 14, 2026

REPORT

Public Comments Processing

Attn: FWS-HQ-ES-2025-0034

U.S. Fish and Wildlife Service
MS: PRB/3W
5275 Leesburg Pike
Falls Church, VA 22041-3803 

Re: COMMENTS ON THE PROPOSED RULE REGARDING RESCISSION OF THE DEFINITION OF “HARM” UNDER THE ENDANGERED SPECIES ACT

Docket number: FWS-HQ-ES-2025-0034

Submitted via Federal eRulemaking Portal: http://www.regulations.gov

INTRODUCTION

On April 17, 2025, the U.S. Fish and Wildlife Service (“FWS”) and the National Marine Fisheries Service (“NMFS”) issued a proposed rule that would rescind the current regulatory definition of “harm” under the Endangered Species Act (“ESA” or the “Act”)[1] and replace it with a much narrower interpretation of that term. See 90 Fed. Reg. 16102 (Apr. 17, 2025).

The ESA, enacted in 1973, contains a variety of protections designed to save from extinction species that the Secretary of the Interior (the “Secretary”) designates as endangered or threatened. Section 9(a)(1) of the Act (16 U.S.C. § 1538(a)(1)) makes it unlawful for any person to “take” any endangered or threatened species within the United States or the territorial sea of the United States.  The ESA defines the statutory term “take” to mean “to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct.16 USC 1532(19). The ESA does not further define the terms it uses in the definition of “take.”

The current regulation (50 CFR § 17.3[2] and hereinafter the “Regulation”), which has been in place since 1975, defines the term “harm” to mean:

“an act which actually kills or injures wildlife.  Such act may include significant habitat modification or degradation where it actually kills or injures wildlife by impairing essential behavioral patterns, including breeding, feeding, or sheltering.”

The FWS and the NMFS assert that, despite almost 50 years of case law, this definition does not reflect the best reading of the statutory text and argue that the definition of “take” should be limited to affirmative, direct acts against individual animals, rather than indirect actions like habitat destruction.

Notably, the current regulatory definition was challenged by plaintiffs in Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, 515 U.S. 687 (1995); however, the Supreme Court found the regulation’s definition was a proper interpretation of the ESA.   The Court in Sweet Home defers to the experts at the Department of the Interior. It also recognizes (but does not strictly rely upon) the ruling of the Supreme Court in Chevron USA Inc v. Natural Resources Defense Council, Inc. 467 US 837 (1984), which holds that if there is an ambiguity in a statute, and a regulation is promulgated to remove such ambiguity, courts will defer to a reasonable interpretation of such statute by the applicable regulatory experts.  Chevron was recently overruled in Loper Bright Enterprises v. Raimondo, 603 U.S. 369 (2024), and thus theoretically any regulation is now subject to challenge.[3]

Rather than wait for a plaintiff to challenge the current regulatory definition of harm under Loper Bright,[4] the FWS and the NMFS propose to undo the last 50 years of ESA protections by pre-emptively rescinding the definition.  As a result, the scope of activities that will require pre-construction or pre-activity permitting or licensing will be far narrower.  Drilling, logging, mining, construction and development operations that formerly would have had to go through the review process under the Regulation, to demonstrate that their project would not harm endangered species before commencing their project, will now be able to proceed rapidly and without independent oversight.[5]

This proposed rescission would undercut decades of settled statutory interpretation, threaten wildlife conservation, and disregard both judicial precedent and Congressional intent.

We submit this comment in strong opposition to the proposed rule.

I. The ESA is clearly designed to avoid destruction of habitat

A limitation on the “take” prohibition of the ESA was added by a 1982 amendment that authorizes the Secretary to grant a permit for any taking otherwise prohibited by § 9 of the Act “if such taking is incidental to, and not the purpose of, the carrying out of an otherwise lawful activity.” 16 USC 1539(a)(1)(B). Other provisions are designed to mitigate the harm that might result from permitted activities. One authorizes the Secretary, in cooperation with the States, to acquire land to preserve species. Significantly, another provision requires federal agencies to ensure that none of their activities, including the granting of permits and licenses, “will jeopardize the continued existence of endangered species” or “result in the destruction or adverse modification of habitat of such species which is determined by the Secretary… to be critical. 16 USC § 1536(a)(2).” Sweet Home, 515 US at 691.

Rescinding the Regulation on the basis that it is too expansive and not the best interpretation of the ESA ignores the clear intent of Congress and the purpose of the ESA to preclude destruction or modification of critical habitat precisely because a species cannot survive unless its habitat also survives.

II. The Inclusion of “Harm” Was Intended to Encompass Indirect Injury

Opponents of the current definition—such as Justice Scalia in his dissent in Sweet Home—argue that “harm” must be narrowly interpreted under the canon of noscitur a sociis, which holds that a word is known by the company it keeps.  The theory holds that since “harm” appears in a list of direct actions (“harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect”), it must also refer to a direct action.

However, this argument fails to account for the canon against surplusage. If all other verbs in the statutory definition of “take” describe direct and intentional conduct such as killing or trapping, then interpreting “harm” as merely another form of direct action renders it redundant.  Courts have consistently held under the canon against surplusage that statutory interpretation should avoid rendering any word or clause meaningless or superfluous.[6]

The most coherent reading, which honors both statutory canons and Congressional intent, is that “harm” was included purposely to broaden the scope of the ESA to include indirect threats such as habitat destruction that result in actual injury or death to protected wildlife.

III. Historical Arguments Against the Current Definition Are Misplaced

Justice Scalia’s dissent in Sweet Home criticized the broad interpretation of “harm,” lamenting that it “contradicts a thousand years of history by converting an ancient prohibition of direct harm to animals into a prohibition of injury to their habitat.”[7] However, the ESA was enacted to address modern and evolving threats to wildlife such as the industrial-scale degradation of habitat—addressing the future, not history. A backward-looking interpretive approach that relies on centuries-old concepts of property and hunting law is incompatible with the statute’s forward-looking conservation goals.

Furthermore, case law has consistently upheld the inclusion of habitat modification as a form of “harm” constituting a “take”:

• Tennessee Valley Authority v. Hill, 437 U.S. 153 (1978) (halting dam construction that would eradicate an endangered species);
• Palila v. Hawaii Department of Land and Natural Resources, 852 F.2d 1106 (9th Cir. 1988) (grazing of sheep that destroyed bird habitat deemed a taking);
• Seattle Audubon Society v. Evans, 952 F.2d 297 (9th Cir. 1991) (significant habitat modification deemed a form of “harm” under the ESA);
• Sierra Club v. Babbitt, 15 F. Supp. 2d 1274 (S.D. Ala. 1998) (prohibiting dune development harming the Alabama beach mouse);
• Friends of Gualala River v. Gualala Redwood Timber, LLC, No. 22-15626 (9th Cir. 2024) (reaffirming the application of habitat-based harm under the ESA).

IV. Legislative Intent Supports Habitat Protection as Core to the ESA

The legislative history of the ESA is unambiguous in its recognition that habitat destruction is a primary driver of extinction. Congress enacted the ESA in response to “economic growth and development untempered by adequate concern and conservation,”[8] and emphasized the importance of protecting ecosystems upon which endangered and threatened species depend.

Today, approximately 1,700 domestic and 700 foreign species are listed under the ESA.[9] For the vast majority of these, habitat loss, not direct exploitation, remains the primary threat. This is consistent with findings by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), which identified habitat degradation as the leading global cause of biodiversity loss, threatening over one million species.[10]

Several species protected through the current regulatory definition of “harm” exemplify the need for this broader interpretation:

• Northern Spotted Owl: Forest habitat preservation upheld under ESA in Seattle Audubon Society;
• Alabama Beach Mouse: Dune development enjoined under the ESA in Sierra Club v. Babbitt;
• California Red-Legged Frog: Habitat protections applied to pesticide review in Ctr. for Biological Diversity v. EPA, No. 02-1580 (N.D. Cal. 2006).

These examples show that the ESA’s effectiveness hinges not on punishing poachers but on preventing habitat degradation that leads to population declines.

V. The Proposed Rule is Inconsistent with Longstanding International Commitments

Finally, independent of the compelling legislative history and decisional law described above, the United States has made international commitments to the conservation of biodiversity and habitats, and related ecological goals. The goals are not served by the proposed rule. Since 1986, the United States has participated as a member-partner of the International Union for Conservation of Nature (IUCN) through IUCN-US, a 501(c)(3) organization that supports IUCN and its global conservation initiatives. The IUCN continues to rely on the United States to honor these longstanding commitments, including domestically.

CONCLUSION

The ESA has been successful in preserving so many species throughout the years specifically because it protects against these indirect threats by the inclusion of the term “harm”.  The definition of “harm” under the ESA is not new, but grounded in legislative intent, judicial precedent, and biological reality. Its inclusion is not a novel regulatory overreach but a critical tool for addressing the leading cause of species extinction in the modern era: habitat destruction.

The rescission of the current definition of “harm” would constitute a devastating step backward in wildlife species conservation and protection. If this new rule is permitted to take effect, one of the most critical guardrails of the ESA –which has as its sole purpose the protection of endangered and threatened species from extinction–will be rendered ineffectual. Indeed, with this new rule, habitat loss and destruction, and the correlative death and extinction of certain species, will not be mere “incidental” outcomes or byproducts —these will be enabled and facilitated to an extent not seen since the enactment of the ESA.

The attempt to rescind this definition does not reflect a better reading of the law; it simply reflects the current administration’s oft-stated goal of promoting business interests in general, and energy extraction in particular,[11] and removing barriers to this goal, even at the expense of the environment and wild animal habitats The FWS and the NMFS have a mandate to enforce and uphold the ESA.  These agencies cannot claim to uphold the ESA while simultaneously gutting the very protections that give it strength. Rolling back the ESA’s abilities to prevent habitat destruction would be a drastic step backward legally and scientifically, and another step towards extinction of an as-yet unknown number of species.  The damage that will be done cannot be undone, and cannot be remedied with eventual litigation success or monetary penalties.

We respectfully urge the FWS and the NMFS to withdraw the proposed rule and retain the current definition of “harm” to preserve the integrity and effectiveness of the ESA.

Animal Law Committee
Martha Golar and Sherry Ramsey, Co-Chairs