United States: New ESA Regulations Expand Impact Of "Critical Habitat" Designations

Elizabeth "Betsy" Lake and Bradley B. Brownlow are Partners and Genna Yarkin is an Associate in our San Francisco office.


  • The U.S. Fish and Wildlife Service and the National Marine Fisheries Service have significantly revised their critical habitat regulatory program under the Endangered Species Act (ESA).
  • The changes, two new rules and one new policy, increase agency discretion to designate habitat currently unoccupied or infrequently used by the listed species, increase the likelihood that activities will result in an adverse destruction finding and generally will expand the impact of the ESA on private lands.

Two new rules and one new policy from the U.S. Fish and Wildlife Service and the National Marine Fisheries Service (the Services) relating to the process of designating and protecting "critical habitat" under the Endangered Species Act (ESA) became effective on March 14, 2016. The new rules revise the criteria for designating critical habitat (see 81 Fed. Reg. 7414, Feb. 11, 2016) and amend the definition of "destruction or adverse modification" of critical habitat (see 81 Fed. Reg. 7214, Feb. 11, 2016). The new policy explains the Services' decision-making criteria in determining whether to exclude areas from critical habitat (see 81 Fed. Reg. 7226, Feb. 11, 2016). Together, the new rules and policy expand the ability of the Services to designate critical habitat, expand the definition of activities that result in "adverse modification" to habitat, and will likely expand the reach of the ESA on private lands across the United States.

Expanded Ability to Designate Unoccupied and Marginally Occupied Areas

In terms of designating critical habitat, the Services' new rules amend 50 CFR 424, which governs what habitat characteristics should be considered when designating lands as critical habitat (see 81 Fed. Reg. 7414). Generally, the new rule emphasizes the importance of designating critical habitat at or near the time species are listed for ESA protection, and broadens the regulatory interpretation of the ESA term "critical habitat." In explaining its revised regulations, the Services repudiated as "an unnecessary and redundant limitation" the prior regulatory approach, which stated that unoccupied habitat can be considered for designation only if a determination is made that the relevant species cannot recover within the area presently occupied by that species. Under the new rule, the Services explicitly revised the approach to consider the designation of unoccupied areas as critical habitat at the outset.

The most significant changes in the rule are as follows:

  • Removing the Services' discretion whether to adopt critical habitat for each species "only where appropriate." The new rule makes it clear that the Services are required to designate critical habitat in a timely manner, providing that critical habitat "shall be proposed and finalized to the maximum extent prudent and determinable at the time a species is proposed for listing." 50 CFR 424.12(a); 81 Fed. Reg. 7432.
  • Defining the previously undefined term "geographical area occupied by the species" to include areas used throughout all or a part of the species' life cycle, "even if not used on a regular basis" and to exclude the statutory modifier "at the time it is listed." 50 CFR 424.02; 81 Fed. Reg. 7429. In response to comments, the Services emphasized the agencies would need to distinguish between areas evidencing periodic use during a species life cycle versus use by a vagrant individual. Additionally, notwithstanding the new emphasis on designating critical habitat at the time of listing, the Services explained that including the requirement to look at occupied habitat at the time listed was too limiting.
  • Defining the term "physical and biological features" to remove the concept of "primary constituent elements" from the prior regulation and instead clarify that such features are those "supporting the life-history needs" of the species and "may include habitat characteristics that support ephemeral or dynamic habitat conditions." 50 CFR 424.02; 81 Fed. Reg. 7430. Thus, under this definition, when considering occupied lands for designation as critical habitat, the Services explained that they are authorized to designate as critical habitat land that does not now contain, but may have once contained, essential features if they believe there is a "reasonable expectation of that habitat occurring again."

Under this new rule, to determine when or what lands to designate as critical habitat, the Services clarify that their discretion is not unbounded – the agencies must rely on the "best available scientific data" (81 Fed. Reg. 7420, 7421, 7426, 7427, 7435). However, given the scarcity of the affected species, the quality of scientific data is not always clear, and there is concern that such "science" may consist solely of circumstantial evidence, and may be vague and merely informed by "any generalized conservation strategy" for a species (50 CFR 424.12(b)(2); 81 Fed. Reg. 7434).

Expanded Definition of "Adverse Modification"

In terms of protecting critical habitat, the new rule amends 50 CFR 502, which governs Section 7 consultation under the ESA, to revise the definition of "destruction or adverse modification" of critical habitat (see 81 Fed. Reg. 7216). This revision was made in response to the Fifth and Ninth Circuits' invalidation of the prior 1986 regulatory definition because it failed to properly require consideration of the impact of adverse modification on recovery of the species in favor of focusing on mere survival. Sierra Club v. U.S. Fish and Wildlife Service, 245 F.3d 434 (5th Cir. 2001); Gifford Pinchot Task Force v. U.S. Fish and Wildlife Service, 378 F.3d 1059 (9th Cir. 2004).

Under this new rule, the ESA term "destruction or adverse modification" at 50 CFR 402.02 is now defined as follows:

[A] direct or indirect alteration that appreciably diminishes the value of critical habitat for the conservation of a listed species. Such alterations may include, but are not limited to, those that alter the physical or biological features essential to the conservation of a species or that preclude or significantly delay development of such features.

Although the Services in response to comment indicate that this definition is merely a reflection of current practice, the definition itself is more expansive – arguably all development would "alter" the land, so the question becomes whether the land altered is essential to conservation. Like the new rule above, the Services rely heavily on the need to use "best available science" as the only restriction on their discretion. As a result, this new rule undoubtedly expands the scope of land disturbance activity that qualifies as destruction or adverse modification in ways not previously anticipated by private landowners.

Consideration of Exclusions to Critical Habitat Designations

While the new rules clarifies what habitat lands to include in critical habitat and how to determine whether activities would result in adverse destruction of that habitat, the nonbinding policy informs the Services' determination of which areas should be excluded from critical habitat designations under section 4(b)(2) of the ESA (81 Fed. Reg. 7226). Specifically, the Services clarify that while there is a mandatory requirement to consider economic and national security issues, there is only a discretionary process to consider conservation plans/partnerships and Tribal lands or military lands. The discretionary analysis involves weighing the benefits of excluding a particular area against the benefits of including that area in the critical habitat designation. Only if the benefits of exclusion outweigh the benefits of inclusion will the Services exclude the particular area from a critical habitat designation. In no circumstances will an area be excluded if its exclusion will result in species extinction.

In undertaking the balancing test, the Services clarified that they will give "great weight" to Tribal or military concerns and will continue to exclude areas covered by a permitted candidate conservation agreement with assurances, a safe harbor agreement or habitat conservation plan if the agreement or plan meets all of the following conditions:

  • the permittee is properly implementing the agreement or plan and is expected to continue doing so
  • the species for which critical habitat is being designated is covered under the plan or agreement, or is similar in its conservation needs to one of the covered species
  • the plan or agreement specifically addresses habitat and meets the conservation needs of the species in the planning area

The Bottom Line

The final rules give the Services broad ability to designate critical habitat and protect it through its Section 7 consultation process. Together, the two new rules and policy appear to significantly 1) expand the ability to designate more lands as critical habitat and 2) once designated, find that more activities result in adverse destruction of that habitat. This revised regulatory regime provides an immense amount of discretion and flexibility for the Services, while creating a great deal of uncertainty for landowners.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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