Interior Department Finalizes Rule Removing Regulatory Definition of Harm Under Endangered Species Act

The Interior Department issued a final rule on July 10 that removes the regulatory definition of "harm" under the Endangered Species Act. The definition had been in place since 1981 and included habitat modification that kills or injures listed species.

The rule follows the Supreme Court's 2024 decision in Loper Bright Enterprises v. Raimondo, which held that courts must exercise independent judgment in interpreting statutes rather than deferring to agency interpretations.

The change affects how the prohibition on "take" of endangered species is applied when habitat is modified. Activities such as farming, drilling, mining, and real estate development that alter habitat are no longer automatically treated as violations under the removed definition.

The original definition was adopted by regulation in 1981. The agency stated that the statutory text of the Endangered Species Act does not define "harm" and that the regulatory definition exceeded the plain meaning of the term.

No statements from the Department of the Interior or the U.S. Fish and Wildlife Service addressing the impact on specific listed species or geographic areas appear in the source materials. The agency did not release estimates of affected acreage or species counts with the final rule.