Feds Propose Rescinding Rule Defining “Harm” in Endangered Species Act

On April 17, 2025, the U.S. Fish and Wildlife Service (“FWS”) and the National Marine Fisheries Service (“NMFS”) published a notice of proposed rulemaking to rescind the agencies’ respective regulatory definitions of “harm” as that term appears in the statutory definition of “take” in the Endangered Species Act (“ESA”), 16 U.S.C. § 1531 et seq.  Comments on the proposed rescission are due by May 19, 2025.  See 90 Fed. Reg. 16102 (Apr. 17, 2025).

The ESA is the principal U.S. law protecting plants and animals that have been designated as likely to face extinction.  The statute therefore broadly prohibits the “taking” of an endangered species.  The statute itself defines “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 U.S.C. § 1532(19).  By regulation, FWS further defined the word “harm” to mean “an act which actually kills or injures wildlife.  Such an act may include significant habitat modification or degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding or sheltering.”  50 C.F.R. § 17.3.  NMFS issued a materially identical definition of “harm.”  50 C.F.R. § 222.102.

The Supreme Court in Babbitt v. Sweet Home Chapter, 515 U.S. 687 (1995), upheld the regulatory definition of “harm,” giving it Chevron deference.  Since Loper Bright Enterprises v. Raimondo, 603 U.S. 369 (2024), overruled Chevron, the agencies now contend that the current definitions do not constitute the “best reading” of the statutory term “harm.”  Instead, the agencies point to the dissenting opinion in Sweet Home, which interpreted “harm” in light of the traditional understanding of “take,” which is to kill or capture a wild animal.  Under this view, “take” requires an affirmative act against the species, not actions that affect the species indirectly.

The agencies recognize that Loper Bright itself stated that prior cases that relied on Chevron are still subject to statutory stare decisis.  However

under the then prevailing Chevron framework, Sweet Home held only that the existing regulation is a permissible reading of the ESA, not the only possible such reading.  Our rescission of the regulation definition on the ground that it does not reflect the best reading of the statutory text thus would not only effectuate the Executive Branch’s obligation to “take Care that the Laws be faithfully executed,” but would also be fully consistent with Sweet Home.

90 Fed. Reg. at 16103

The rescission of the regulatory definition of “harm” seems geared to address scenarios in which, for example, a construction project does not directly kill or injure a species but modifies the species’ habitat and thereby forces it to vacate the area. 

The rulemaking presents several issues worth considering.

First, on the substance, while the agencies propose to rescind the definition of “harm,” they do not propose rescinding the regulatory definition of “harass.”  “Harass” is defined in part to mean “annoying [the species] to such an extent as to significantly disrupt normal behavioral patterns which include, but are not limited to, breeding, feeding, or sheltering.”  50 C. F. R. § 17.3. (NMFS has no parallel definition of “harass.”)  It would seem that most actions that amount to “harm” on the basis of habitat degradation would also constitute “harassment.”

Second, the rulemaking probably has no impact on endangered species maintained in a captive environment.  Even if the “harm” definition is rescinded, the “harass” definition remains and, as it applies to captive wildlife, “harass” has been consistently defined by FWS to exclude “animal husbandry practices that meet or exceed the minimum standards for facilities and care under the Animal Welfare Act.”  50 C.F.R. § 17.3.  That is, while a captive endangered species cannot be lawfully “harassed” under the ESA, there is no such harassment if the endangered species is held under conditions that comply with the Animal Welfare Act (“AWA”). However, since “harm” was not defined with a link to the AWA, the deletion of the “harm” definition would eliminate the potential ambiguity that a captive species can be “harmed” even if the actions at issue are AWA-compliant.

Third, the rulemaking will likely test the contours of the Loper Bright pronouncement on statutory stare decisisSweet Home was a Chevron-based case, but the agencies seem to be taking the position that statutory stare decisis will not control the outcome because their actions are required by the Executive Branch’s constitutional duty to take care that the laws be faithfully executed.  90 Fed. Reg. at 16103 (citing U.S. Const. art. II, § 3).

Ecuadorian Animal Rights Decision is Mixed Bag

Animal rights activists have pointed to a recent decision by the highest court in Ecuador — the Constitutional Court (Corte Constitucional Del Ecuador) — as a breakthrough for animal rights.  As the NonHuman Rights Project (NHRP)  described it, the decision “constitutes one of the most important advances in the field of animal rights and environmental law in recent years. . . .  The Court’s groundbreaking ruling advances the constitutional protection of animals — ranging from the level of species to the individual animal — with their own inherent value and needs.”

Upon closer examination, the Court’s Final Judgment is not as far-reaching as has been claimed.  Continue reading “Ecuadorian Animal Rights Decision is Mixed Bag”

Federal Court Enjoins California Ban on Sale of Alligator and Crocodile Parts

by John M. Simpson.

On Tuesday, a federal district court in California enjoined the enforcement of Cal. Penal Code § 653o which criminalizes the sale and possession for sale of alligator and crocodile parts in California.  April in Paris v. Becerra, No. 2:19-cv-02471-KJM-CKD, consolidated with Louisiana Wildlife Fisheries Comm’n v. Becerra, No. 2:19-cv-02488-KJM-CKD (E.D. Cal. Oct. 13, 2020).  Plaintiffs, business interests importing alligator and crocodile parts into California, brought the action against the California Attorney General and the Director of the state Department of Fish and Wildlife.  The law had been slated to take effect on January 1, 2020, but had been suspended pursuant to a stipulated retraining order pending the court’s decision on the preliminary injunction motion. Continue reading “Federal Court Enjoins California Ban on Sale of Alligator and Crocodile Parts”

Ninth Circuit Rejects Activist Appeal in Endangered Dugong Case

by John M. Simpson.

On May 6, 2020, the U.S. Court of Appeals for the Ninth Circuit affirmed the district court’s grant of summary judgment to the government in a case brought by the Center for Biological Diversity and other plaintiffs to challenge a decision by the Department of Defense (DOD) approving a plan to construct a replacement aircraft base in Okinawa, Japan, for the U.S. Marine Corps.  Center for Biological Diversity v. Esper, __ F.3d __, No. 18-16836 (9th Cir. May 6, 2020).  In this case, which had originated in 2003, the issue was whether DOD had complied with section 402 of the National Historic Preservation Act (NHPA), 54 U.S.C. § 307101(e). Continue reading “Ninth Circuit Rejects Activist Appeal in Endangered Dugong Case”

Animals and Politics: Traveling Exotic Animal Ban Reintroduced

by Michelle C. Pardo

On May 21, 2019 Representatives Raul M. Grijalva (D-AZ) and David Schweikert (R-AZ) introduced the Traveling Exotic Animal and Public Safety Protection Act (TEAPSPA), a bill that would amend the federal Animal Welfare Act to prohibit the use of exotic and wild animals, including lions, tigers and elephants, in traveling performances.  The bill had previously been introduced in 2017. Continue reading “Animals and Politics: Traveling Exotic Animal Ban Reintroduced”

Endangered Species Act Case Founders on Lack of 60-Day Notice

By John M. Simpson

A federal district court in New Hampshire recently dismissed a citizen suit making novel claims under the Endangered Species Act (ESA) because the plaintiff could not prove that he had provided the required 60-day notice to the defendants prior to suit.  Strahan v. Nielsen, 2018 WL 3966318 (D.N.H. Aug. 17, 2018).  Continue reading “Endangered Species Act Case Founders on Lack of 60-Day Notice”

Fourth Circuit Vacates Incidental Take Statement for Gas Pipeline

by John M. Simpson

On August 6, 2018, the U.S. Court of Appeals for the Fourth Circuit granted a petition setting aside an Incidental Take Statement (ITS) of the U.S. Fish and Wildlife Service (FWS) which had been issued under the Endangered Species Act (ESA)  in connection with the approval of the Atlantic Coast Pipeline, a 600-mile natural gas pipeline proposed to run through parts of West Virginia, Virginia and North Carolina.  Sierra Club, et al., v. U.S. Dep’t of the Interior, Nos. 18-1082 & 18-1083 (4th Cir. Aug. 6, 2018).   Continue reading “Fourth Circuit Vacates Incidental Take Statement for Gas Pipeline”

Court Grants Summary Judgment Against HSUS in Endangered Species Act Case

by John M. Simpson

The U.S. District Court for the District of New Mexico recently entered summary judgment against the Humane Society of the United States (HSUS) and other plaintiffs in a case brought under the Endangered Species Act (ESA) alleging that regulations issued by the New Mexico State Game Commission authorizing the  recreational trapping of cougars (Cougar Rule) will cause a “take” of Mexican gray wolves in violation of the ESA.  Humane Soc’y of the U.S. v. Kienzle, 2018 WL 3429924 (D.N. M. July 16, 2018).  Continue reading “Court Grants Summary Judgment Against HSUS in Endangered Species Act Case”

Fisheries Service Designates Critical Habitat for False Killer Whale Population

On July 24, 2018, the National Marine Fisheries Service (NMFS)  published a final rule in the Federal Register designating critical habitat for the Main Hawaiian Islands insular false killer whale distinct population segment.   The rule becomes effective on August 23, 2018. Continue reading “Fisheries Service Designates Critical Habitat for False Killer Whale Population”

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The opinions expressed on this blog are those of the author and are not to be construed as legal advice.

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