The “Harm Rule” Rescinding Protections Under The Endangered Species Act Creates Significant Uncertainty For Developers

The “Harm Rule” adopted by U.S. Fish and Wildlife Service (“FWS”) and National Marine Fisheries Service (“NMFS”) on July 14, 2026, and effective as of September 14, 2026, rescinds the longstanding regulatory definition of "harm" found in each agency’s Endangered Species Act (ESA) regulations.¹ The practical effect of this change is that habitat modification or degradation is no longer considered "take" under the federal ESA. Perhaps even more significantly, though, a guidance memorandum issued by FWS² reveals the sweeping scope of that agency’s interpretation of the Harm Rule, which extends well beyond mere recission of the prior regulatory definition of harm. Both the Harm Rule and the FWS’s interpretative guidance may usher in a new era in which FWS will only identify as “take” affirmative acts that are directed intentionally and immediately at listed species.