What the Rescission of the ESA “Harm” Definition Means for Natural Resources
Environmental regulations can have a significant influence on how development, infrastructure, energy, and other projects are planned and permitted. One recent federal regulatory change that may affect natural resources considerations is the rescission of the regulatory definition of “harm” under the Endangered Species Act (ESA).
Effective September 14, 2026, the U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) have removed the regulatory definition of “harm” from the Code of Federal Regulations. The final rule was published July 14, 2026, and applies to the ESA regulations administered by the two agencies.
What Is “Harm” Under the ESA?
The ESA prohibits the “take” of federally protected endangered wildlife. The statute defines “take” to include actions such as harassing, harming, pursuing, hunting, shooting, wounding, killing, trapping, capturing, or collecting protected wildlife, or attempting to engage in such conduct.
For decades, the federal regulations included a specific definition of “harm.” That definition extended beyond direct injury or mortality to certain actions that could result in injury or death through habitat modification or degradation.
Under the previous regulatory definition, habitat modification or degradation could constitute “harm” when it actually killed or injured wildlife by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering.
The new rule removes that regulatory definition.
What Changed on September 14?
As of today, the specific regulatory definition of “harm” is no longer included in 50 CFR Parts 17 and 222. The USFWS and NMFS stated that the change is intended to align implementation of the ESA with what the agencies consider to be the best meaning of the statutory term “take.”
Importantly, this does not eliminate the ESA or its protections for federally listed species.
The ESA itself remains in place, including its statutory definition of “take.” The federal agencies have also stated that actions that directly injure or kill listed wildlife remain prohibited and that existing permits and incidental take statements remain valid.
Why Does This Matter for Project Planning?
The change may be particularly relevant to projects where development or construction activities occur near federally listed species or their habitat.
Natural resources evaluations often consider whether a proposed project could affect protected species, their habitat, wetlands, waterways, or other environmentally sensitive resources. Depending on the project and the species involved, these considerations can influence site planning, construction methods, timing, avoidance measures, permitting, and federal consultation requirements.
With the previous regulatory definition of “harm” now rescinded, the way potential impacts associated with habitat modification are evaluated may change.
However, the practical implications will depend on the specific project, species, federal nexus, applicable regulations, and agency interpretation.
What Has Not Changed?
The rescission of the regulatory definition does not mean that environmental considerations related to protected species and habitat are no longer important.
Federally listed species continue to receive protection under the ESA, and the statute continues to prohibit the unauthorized “take” of protected wildlife. The ESA also continues to address the conservation of endangered and threatened species and the protection of their habitat.
For project teams, this means that natural resources due diligence remains an important part of responsible project planning.
Early identification of potential species and habitat concerns can help project proponents understand environmental constraints before construction begins and determine whether additional surveys, agency coordination, avoidance measures, or other environmental considerations may be appropriate.
What Should Project Proponents Consider?
For landowners, developers, municipalities, infrastructure providers, and other project proponents, the regulatory change is an important reason to stay current on federal natural resources requirements.
Project teams should continue to consider:
- Whether federally listed species or their habitat may occur within or near a project area
- Whether the project has a federal nexus that could trigger additional ESA requirements
- Whether proposed activities could directly or indirectly affect protected species
- Whether species surveys or habitat assessments may be appropriate
- Whether project design or construction practices can avoid or minimize potential impacts
- Whether federal, state, or local environmental requirements apply independently of the ESA
The appropriate level of evaluation will vary based on the location, project type, environmental setting, and resources present.
What Does This Mean for the Future?
The rescission of the regulatory definition of “harm” represents a significant change in the federal approach to implementing the ESA, but its full practical impact will develop over time as agencies, courts, consultants, and project proponents apply the revised regulatory framework.
The rule itself is also part of a broader set of recent federal changes to ESA regulations. USFWS and NMFS have issued additional revisions addressing threatened-species protections and critical habitat, making it increasingly important for project teams to monitor regulatory developments rather than rely solely on historical permitting practices.
For projects involving potential impacts to protected species or environmentally sensitive areas, understanding the current regulatory landscape early can help identify potential constraints and inform project planning.
Staying Ahead of Natural Resources Requirements
Environmental regulations continue to evolve, and changes to federal requirements can have implications for projects at the planning, design, permitting, and construction stages.
At ESE Partners, our Natural Resources team helps clients evaluate environmental considerations associated with their projects, identify potential constraints, and navigate applicable regulatory requirements. By considering natural resources early in the project lifecycle, clients can make informed decisions and address potential environmental issues before they become project obstacles.
As the implementation of the revised ESA framework develops, continued monitoring of federal requirements and agency guidance will be important for projects where federally protected species or habitat may be present.
