not yet effective
Effective 2026-08-20 per the Federal Register.
This is a final rule from the U.S. Fish and Wildlife Service (FWS) that revises its regulations under Section 4(b)(2) of the Endangered Species Act, which govern “critical habitat” — the areas identified as essential to a listed species’ survival. It sets out when and how the agency decides to leave a particular area out of a critical habitat designation, a step the document calls an “exclusion analysis.” The rule states its purpose is to make that exclusion process more transparent and predictable.
The rule takes effect August 20, 2026, and reinstates FWS-specific regulations at 50 CFR 17.90, replacing the agency’s 2016 policy and the shared 50 CFR 424.19 standards as they apply to FWS. It lays out a two-step method: FWS first checks whether designating an area causes any meaningful economic, national-security, or “other relevant” impact; only if such an impact exists does it move to weighing the benefits of excluding the area against the benefits of including it. It adds a “credible information” standard that a party requesting an exclusion must meet before FWS will run that weighing analysis, and it clarifies that these procedures apply only to Section 4(b)(2) exclusions, not to the separate Section 4(a)(3) “not prudent” determination. The rule applies only going forward — to critical habitat rules finalized after the effective date — and does not require any past designations to be reopened. Two minor wording edits were made from the proposed version (“FWS’s” changed to “Service’s,” and “assign” changed to “give”).
The rule applies only to the Fish and Wildlife Service and does not change the process used by the National Marine Fisheries Service, which handles most marine species. It directly affects landowners, industry, states, Tribes, local governments, and others who may request that specific areas be excluded from future critical habitat designations, since it defines what information they must provide and how their requests will be weighed. It also affects listed species and their habitat, because it governs how areas essential to conservation may be included in or left out of future designations. FWS reported receiving 12,532 comment submissions representing about 306,628 individuals during the 30-day comment period.