January 25, 2021
Final Rules Amending ESA Critical Habitat Regulations
In December 2020, the Trump Administration published
FWS’s critical habitat designation for the dusky gopher frog
two final rules amending certain regulations that implement
included areas occupied and unoccupied by the species. In
the Endangered Species Act (ESA; 16 U.S.C. §§1531 et
the rule, FWS identified three features of the occupied areas
seq.) as it relates to critical habitat. The first rule defines
essential to the frog’s conservation: (1) ephemeral ponds for
habitat, and the second clarifies when the U.S. Fish and
breeding, (2) open-canopy forest with holes and burrows
Wildlife Service (FWS) may exclude certain areas from
for dwelling, and (3) open-canopy forest connecting
designation as critical habitat. The final rules are effective
breeding and dwelling areas. FWS determined, however,
as of specified dates in January 2021 and apply only to
that the occupied area was insufficient to conserve the
critical habitat designations proposed after the rules take
species, and it therefore considered designating unoccupied
effect. The Biden Administration has indicated it will be
areas as critical habitat. The unoccupied area at issue in the
reviewing these rules pursuant to Executive Order 13990.
case had only one of the essential features—ephemeral
ponds—because much of the site was a closed-canopy
The ESA is implemented by the Secretary of the Interior,
timber plantation. But FWS concluded that the high-quality
through the FWS, and the Secretary of Commerce, through
ephemeral ponds in the area were a unique resource, and
the National Marine Fisheries Service (NMFS) in the
that the other features necessary for occupation could be
National Oceanic and Atmospheric Administration. As
restored “with reasonable effort.” As such, FWS found the
defined in the ESA, the Secretary refers to either Secretary
area “essential” and designated it as critical habitat.
as appropriate. FWS and NMFS are jointly referred to as
the Services.
Private landowners challenged the designation, arguing that
the unoccupied area could not be the frog’s critical habitat
The ESA defines critical habitat to include areas that are
because it lacked two of the three “essential” features. They
occupied and unoccupied by the species at the time of
also argued that FWS inadequately weighed the benefits of
listing (16 U.S.C. §1532(5)). To be designated as critical
designating the area against the economic impact.
habitat, occupied areas must contain physical or biological
features that are essential to the species’ conservation and
The Supreme Court held that in order to be critical habitat,
may require special management. Unoccupied areas must
an area must first be habitat for the species. The Court
be “essential for the conservation of the species.” The act
reasoned that the ordinary understanding of adjectives as
does not define habitat. Section 4 of the ESA also allows
modifying nouns requires that critical habitat be a subset of
the Secretary to exclude areas from being designated as
habitat. It also examined the statutory context and observed
critical habitat if “the benefits of such exclusion outweigh
that Section 4 of the ESA (16 U.S.C. §1533) requires the
the benefits of specifying such area” unless such exclusion
Secretary to “designate any habitat of [a listed] species
will result in extinction of the species concerned.
which is then considered to be critical habitat.”
Accordingly, the Court reasoned, only areas first
Areas designated as critical habitat are subject to certain
determined to be habitat for a species could be designated
statutory restrictions. Federal agencies must ensure that
as critical habitat. Because neither the statute nor the
their actions will not adversely affect designated critical
Services’ regulations defined habitat, and FWS had not
habitat (16 U.S.C. §1536). Critical habitat designations
defined habitat for the dusky gopher frog for purposes of
affect private parties only when their actions require
the rule, the Court remanded the case to the Fifth Circuit to
funding or approval by a federal agency (e.g., federal
determine what “habitat” means in the ESA context.
permits).
The Supreme Court also addressed excluding areas from a
This In Focus summarizes the two final rules along with
critical habitat designation. The ESA provides that FWS
some of the Services ’ explanations for the changes. Both
may exclude an area from critical habitat based on
rules were issued, in part, in response to the Supreme
Court’s decision in
economic impacts (16 U.S.C. §1533(b)(2)). In designating
Weyerhaeuser Co. v. U.S. Fish &
critical habitat for the dusky gopher frog, FWS declined to
Wildlife Service (139 S. Ct. 361, 2018).
exclude the petitioners’ private property on that basis. The
Weyerhaeuser Co. v. U.S. FWS
Fifth Circuit determined that FWS’s decision not to exclude
an area from critical habitat was committed to the agency’s
In Weyerhaeuser, the Supreme Court reviewed a decision
discretion and not reviewable. The Supreme Court
by the U.S. Court of Appeals for the Fifth Circuit upholding
FWS’s critical habitat designation for the dusky gopher
disagreed, concluding that the ESA provided sufficient
guidance for a court to review such decisions for abuse of
frog, Rana sevosa. First, the Court held that an area must be
discretion. Accordingly, the Court also remanded the case
habitat in order to be critical habitat. Second, it concluded
for the Fifth Circuit to examine whether FWS abused its
that courts can review agency decisions not to exclude areas
discretion in declining to exclude the petitioners’ land.
from critical habitat on economic grounds.
https://crsreports.congress.gov

Final Rules Amending ESA Critical Habitat Regulations
On remand, FWS ultimately agreed in a settlement to
outweigh the benefits of specifying the area, unless failing
remove the area from the critical habitat designation. The
to designate such area will result in the species’ extinction.
two final rules respond, in part, to Weyerhauser by defining
The previously existing regulations, which are to continue
habitat and clarifying FWS’s process for analyzing whether
to apply to NMFS, required the Services to publish a draft
to exclude areas from critical habitat designations.
economic analysis of the designation for public comment
and to consider economic, national security, and other
Regulations for Listing Endangered and
relevant impacts of the designation, at a scale the Services
Threatened Species and Designating
consider appropriate, before finalizing the designation. In
Critical Habitat
deciding whether to exclude any area from a critical habitat
The Services published a final rule, Regulations for Listing
designation, the regulations allowed the Services to assign
Endangered and Threatened Species and Designating
the weight given to any benefits of excluding or including
Critical Habitat (85 Federal Register [FR] 81411), on
the area. NMFS is to continue to use the previously existing
December 16, 2020, effective on January 15, 2021. The rule
regulations at 50 C.F.R. §424.19.
added a definition of habitat to the ESA’s implementing
regulations at 50 C.F.R. Part 424.
The new final rule applies to critical habitat designations
proposed by FWS. Those new regulations, codified at 50
The definition of habitat added to 50 C.F.R. §424.02 is
C.F.R. §17.90, generally carry over the provisions of 50
C.F.R. §424.19 but provide examples of factors FWS is to
Habitat. For the purposes of designating critical
consider relevant for “economic impacts” and “other
habitat only, habitat is the abiotic and biotic setting
relevant impacts” and specify when FWS is to conduct an
that currently or periodically contains the resources
exclusion analysis. The final rule notes that under the ESA,
and conditions necessary to support one or more life
FWS generally has discretion whether to conduct an
processes of a species.
exclusion analysis of an area. But the final rule limits that
discretion by requiring FWS to conduct an exclusion
In the rule, the Services identify the Supreme Court’s
analysis when a proponent for excluding a particular area
holding in Weyerhaeuser as an impetus to define habitat.
provides credible and meaningful information about the
Specifically, they cite the Court’s holding that critical
economic or other impacts of designating the area.
habitat must logically be a subset of habitat and that the
ESA therefore “does not authorize the Secretary to
FWS’s new regulations also outline principles for the
designate the area as critical habitat unless it is
Secretary to consider when weighing the benefits of
also habitat for the species” (Weyerhaeuser, at 368). The
including or excluding particular areas as critical habitat.
Services stated in the proposed rule that defining habitat
For example, for areas outside of FWS’s expertise, such as
would “help ensure that unoccupied areas that [they]
nonbiological or national security impacts, the regulations
designate as critical habitat are ‘habitat’ for the species and
direct the Secretary to give weight to information from
are defensible as such.” The Services also clarified that this
experts and firsthand sources. The regulations also establish
definition of “habitat” applies only “for the purposes of
conditions for considering the exclusion of areas that have
designating critical habitat”; that setting is “to have its
conservation plans, agreements, or partnerships authorized
common meaning, such as the time, place, and
under Section 10 of the ESA (16 U.S.C. §1539) for the
circumstances in which something occurs or develops”; and
species in question. Information provided by outside
that life processes has its “common biological meaning, that
proponents is to be evaluated on a “case-by-case basis,” and
is, to include a series of functions … that are essential to
in order for information to be credible, it must be “factual
sustain a living being.”
information” documenting “a meaningful impact” that
supports excluding an area from critical habitat designation.
Regulations for Designating
Critical Habitat
The new regulations require FWS to exclude an area from
critical habitat designation when it concludes that the
FWS published a second final rule, Regulations for
benefits of exclusion outweigh the benefits of designating
Designating Critical Habitat (85 FR 82376), on December
the area as critical habitat, unless failure to designate that
18, 2020, effective on January 19, 2021. The rule modifies
area will result in the species’ extinction. Some commenters
FWS’s process for determining when to exclude areas from
noted that requiring the Secretary to exclude areas from
critical habitat. According to FWS, the intention of these
critical habitat upon a favorable exclusion analysis
regulations is “to provide greater transparency and certainty
contradicts the purpose of the act. FWS responded by
for the public and stakeholders.”
stating that “the regulation constitutes the Secretary’s
Prior to the final rule’s effective date, 50 C.F.R. §424.19
decision on how to exercise his discretion.” The existing
provided the process for determining exclusions from
regulations, which still apply to NMFS, allowed the
critical habitat for both Services. Section 4 of the ESA
Services “discretion to exclude any particular area from the
directs the Secretary to designate critical habitat for listed
critical habitat upon” such a determination.
species based on the best scientific data available and after
taking into consideration economic, national security, and
R. Eliot Crafton, Analyst in Natural Resources Policy
other relevant impacts of such a designation. As noted, the
Pervaze A. Sheikh, Specialist in Natural Resources Policy
Services may exclude areas from critical habitat
Erin H. Ward, Legislative Attorney
designations if, based on an exclusion analysis, the
Secretary determines that the benefits of excluding the area
IF11740
https://crsreports.congress.gov

Final Rules Amending ESA Critical Habitat Regulations


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