Friends of Animals v. Martha Williams
CourtCourt of Appeals for the D.C. Circuit
Date FiledAugust 11, 2026
Docket24-5278
StatusPublished
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Full Opinion
United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued December 5, 2025 Decided August 11, 2026
No. 24-5278
FRIENDS OF ANIMALS,
APPELLEE
v.
MARTHA WILLIAMS, IN HER OFFICIAL CAPACITY AS PRINCIPAL
DEPUTY DIRECTOR AND UNITED STATES FISH AND WILDLIFE
SERVICE, AN AGENCY OF THE UNITED STATES,
APPELLANTS
Appeal from the United States District Court
for the District of Columbia
(No. 1:21-cv-02081)
Christopher Anderson, Attorney, U.S. Department of
Justice, argued the cause for appellants. With him on the briefs
were Adam R.F. Gustafson, Acting Assistant Attorney General,
Robert N. Stander, Deputy Assistant Attorney General, and
Emily Anne Polachek, Attorney.
Stephen R. Hernick argued the cause for appellee. With
him on the brief was Jennifer Best.
2
Before: HENDERSON, PILLARD and WILKINS, Circuit
Judges.
Opinion for the Court filed by Circuit Judge WILKINS.
WILKINS, Circuit Judge: Section 1533(e) of the
Endangered Species Act (“ESA”) allows the Fish and Wildlife
Service (“the Service”) to “treat any species as an endangered
or threatened species even though it is not listed pursuant to”
the ESA, provided that the Service fulfills certain criteria. 16
U.S.C. § 1533(e). One such criterion is that a species not itself
endangered or threatened may be treated as such if similar in
appearance to one that is. Id. But the Service has long
recognized that § 1533(e) does not empower it to conduct a
similarity of appearance analysis for any species that is already
listed as endangered or threatened. Friends of Animals
(“Friends”) contests this interpretation, particularly in the
context of the scarlet macaw, and argues that the statute does
authorize a similarity of appearance-based listing for even
those species that are already listed as endangered or
threatened. The District Court below found in favor of Friends’
interpretation of the provision, relying on the statutory text and
overall purpose of the ESA. We now reverse.
I.
Congress enacted the ESA in 1973 and authorized the
Service to designate species—divided separately into
Subspecies and distinct population segments (“DPS”)—as
endangered or threatened based on several criteria. 16 U.S.C.
§§ 1532(16), 1533(a). A species is generally designated as
“endangered” when it is “in danger of extinction throughout all
or a significant portion of its range,” id. § 1532(6), whereas a
species is designated as “threatened” when, within the
“foreseeable future,” it is “likely to become an endangered
3
species,” id. § 1532(20). The distinction is important because
while the ESA contains an express provision prohibiting
certain actions against endangered species, there are no similar
statutory protections for threatened species. Id. § 1538(a).
Instead, the Service must specifically issue “regulations as [it]
deems necessary and advisable to provide for the conservation”
of threatened species. Id. § 1533(d). Section 1533(d) also
permits the Service to “extend[] the 16 U.S.C. § 1538(a)(1)
prohibitions as to endangered species to all threatened species
as well,” Sweet Home Chapter of Cmtys. for a Greater Or. v.
Babbitt, 1 F.3d 1, 5 (D.C. Cir. 1993), and the Service has done
so, see 50 C.F.R. § 17.31(a). In that rule, the Service has
reserved the ability to “promulgate[] species-specific
provisions,” id., thereby enabling it to selectively withhold
from a specified population protection that would otherwise
extend to the threatened species by virtue of the blanket rule.
Congress also recognized that species visually similar to
endangered or threatened species, but not independently listed
as such, could pose an additional threat to those listed species
if they were not afforded the same protections. For instance, a
hunter or poacher could kill an endangered animal and claim
that they thought it was an unprotected animal that closely
resembles the protected species. Accordingly, the ESA also
authorizes the Service to “treat any species as an endangered or
threatened species even though it is not listed” pursuant to
§ 1533(a) of the ESA when: (A) “such species so closely
resembles in appearance . . . a species which has been listed
pursuant to such section that enforcement personnel would
have substantial difficulty in attempting to differentiate
between the listed and unlisted species;” (B) “the effect of this
substantial difficulty is an additional threat to an endangered or
threatened species;” and (C) “such treatment of an unlisted
species will substantially facilitate the enforcement and further
the policy” of the ESA. 16 U.S.C. § 1533(e)(A)–(C). By
4
regulation, the same protections applicable to listed endangered
or threatened species automatically apply to those species
treated as endangered or threatened based on similarity of
appearance, although the Service may depart from the default
extension of protections in species-specific rules. 50 C.F.R. §§
17.51–52. In other words, if a species is treated as endangered
because it looks visually similar to an endangered species, then
the protections afforded to that endangered species are
automatically extended to the visually similar species.
In 2019, the Service exercised its power under the ESA
and extended protections to certain subspecies of the scarlet
macaw, a parrot native to Central and South America. The
scarlet macaw is subdivided into two subspecies: the Northern
Subspecies and the Southern Subspecies. The Southern
Subspecies is further divided into the Northern DPS and the
Southern DPS. In the 2019 Final Rule, issued in February 2019
and made effective a month later, the Service listed the
Northern Subspecies as endangered and the Northern DPS of
the Southern Subspecies as threatened. Endangered and
Threatened Wildlife Plants; Listing the Scarlet Macaw, 84 Fed.
Reg. 6278, 6307–08 (Feb. 26, 2019). Exercising its § 1533(e)
authority, the Service also treated the Southern DPS of the
Southern Subspecies as threatened based on similarity of
appearance to the Northern DPS and the Northern Subspecies.
Id. at 6308–09. By regulation, this meant that the threatened
Southern DPS would obtain many of the same protections as
the statute affords to the endangered Northern Subspecies.
However, the Service expressly carved out one such protection
as inapplicable: Its rule allows import and export of Southern
DPS and Northern DPS macaws born in captivity without a
permit. Id. at 6309–10.
5
Scarlet
Macaw
Northern
Subspecies Southern
Endangered Subspecies
Northern Southern
DPS DPS
Threatened Threatened
Based on
Similarity of
Appearance
Friends brought suit in 2021, alleging that the Service had
acted arbitrarily and capriciously in violation of the
Administrative Procedure Act (“APA”) by failing to consider
whether the Northern DPS of the Southern Subspecies should
be treated as endangered—even though it was already listed as
threatened—based on the Northern DPS’s similarity of
appearance to the Northern Subspecies. If the Service had done
so, the Northern DPS would have received the same protection
as an endangered species, rather than the “lesser” protection
afforded to a threatened one. In the proceedings below, on
cross motions for summary judgment from both parties, the
6
District Court ruled that the Service violated the APA, finding
that its interpretation of § 1533 as precluding a similarity of
appearance analysis for an already listed species was “flawed.”
J.A. 064. This was for two reasons: First, the District Court
found that the Service’s interpretation would render the term
“any,” as utilized in § 1533(e), “superfluous”; second, the
District Court concluded that such an interpretation would
contravene the ESA’s core purpose to conserve, protect, and
defend species from extinction. J.A. 063–66. 1
In July 2024, the District Court issued an order denying in
part and granting in part both the Service’s and Friends’
summary judgment motions. Deciding that the APA issue
warranted “further explanation” from the agency, the District
Court subsequently remanded that issue, amongst others, to the
Service. J.A. 077 (stating that issues that “warrant further
explanation . . . will be remanded to the agency”). It then noted
that it “will . . . defer final decision on the precise parameters
and duration of that remand,” ordering the parties to “meet,
confer, and submit a joint proposal on the scope and duration
of the remand.” J.A. 077. The parties ultimately submitted two
separate proposals to the District Court and the District Court
granted the Service’s remand proposal in October 2024. In its
October Order, the District Court stated that it had “remanded
two issues to the Service for further explanation [in July] but
deferred final decision on the parameters and duration of [the]
remand” until October. J.A. 081. The Service subsequently
appealed the District Court’s denial of its summary judgment
motion in December 2024, less than 60 days after the October
Order. We have jurisdiction to review under 28 U.S.C § 1291.
1
The District Court also decided a number of other issues raised by
the parties in the proceeding below that neither party presses on
appeal.
7
II.
We first address Friends’ myriad procedural arguments,
each of which is without merit.
Friends first argues the Service’s appeal is untimely as it
filed its appeal more than 60 days after the District Court’s July
Order. The Service responds that its appeal is timely because
it filed its appeal within 60 days of the District Court’s October
Order. The substance of their disagreement boils down to
whether the July Order or the October Order “conclusively
determine[d] the disputed question”—in other words, which of
the Orders contains the “final decisions” from which an appeal
may be taken. Occidental Petroleum Corp. v. SEC, 873 F.2d
325, 328–29 (D.C. Cir. 1989) (citation modified).
We hold that it is the October Order, and as such, the
Service’s appeal is timely. The District Court’s July Order did
not “conclusively determine” the disputed question, in part
because it left open the precise parameters and duration of the
ordered remand. Id. at 329. Further, the District Court made
clear in its July and October Orders that its July Order had been
non-final. It stated in the July Order that it was “defer[ring]
final decision on . . . that remand” and emphasized in the
October Order that it had previously “deferred final decision
on the parameters and duration of remand.” J.A. 077, 081. We
must take this express denial of the District Court’s finality at
its word. St. Marks Place Hous. Co. v. Dep’t of Hous. & Urban
Dev., 610 F.3d 75, 80 (D.C. Cir. 2010). Given that the District
Court made abundantly clear in its July Order that it was not
yet done determining the scope of the remand, the July Order
was not a final decision from which the time to appeal began
to run; therefore, the Service’s appeal is timely.
8
Friends’ untimeliness arguments ostensibly extend to
standing. The organization contends that the Service lacks
standing to appeal because appeals from remand orders are
interlocutory, the Service appealed from the October Order,
and “interlocutory appeals are ‘confined to the particular order
appealed from.’” Appellee Br. at 26 (quoting United States v.
Stanley, 483 U.S. 669, 677 (1987)). To state it more plainly,
Friends claims that the Service’s arguments related to the best
reading of § 1533(e) could only have been raised on an
interlocutory appeal from the July Order, which found that the
issue should be remanded to the agency, and not the October
Order, which related to the parameters and duration of that
remand.
We find this claim unavailing. Friends’ contention relies
upon cases involving statutes that authorize appeals from
specific orders certified by the district court, such as 28 U.S.C.
§ 1292(b). In contrast, this Court has jurisdiction to review
appeals under 28 U.S.C. § 1291, which confers jurisdiction to
review “final decisions” of the district courts. As explained
above, the October Order is the “final decision” of the District
Court. And that order implicitly adopted the July Order by
express reference. Friends’ second procedural argument thus
fails.
Friends’ third procedural argument—centered around the
Service’s Notification of Final Explanation, which was issued
after the District Court’s October Order—is equally
unpersuasive. The Service noted in the Notification of Final
Explanation that it was “explain[ing] why [it] did not conduct
an analysis under [16 U.S.C. § 1533(e)] pertaining to the
[Northern] DPS,” and that it was now conducting such
explanation “[i]n response to an order by the” District Court.
Similarity of Appearance Explanation for the Northern Distinct
9
Population Segment of the Southern Subspecies of Scarlet
Macaw, 90 Fed. Reg. 43395, 43395 (Sept. 9, 2025). Friends
asserts that the issuance of this explanation “completes the
[District Court’s] remand” and “renders [the Service’s] appeal
moot.” Letter Pursuant to FRAP 28j at 1–2, No. 24-5278
(dated Sept. 12, 2025). This argument is clearly incorrect
under our precedent. It is a long-held tenet that “[a]gency
compliance with [a court] mandate does not moot the issue of
the correctness of the court’s decision.” Norfolk and Western
Ry. Co. v. Am. Train Dispatchers Ass’n, 499 U.S. 117, 128 n.3
(1991); see also Maher v. Roe, 432 U.S. 464, 468 n.4 (1977),
Schweiker v. Gray Panthers, 453 U.S. 34, 42 n.12 (1981),
Cornelius v. NAACP Legal Def. & Educ. Fund, Inc., 473 U.S.
788, 791 n.1 (1985). So too here.
Friends then contends that the Service provided a post-hoc
rationale in its arguments on appeal because the Service had
not explained in the administrative record why it was not
conducting a similarity of appearance analysis for the Northern
DPS, nor why the ESA prohibited it from doing so. But the
reason why the Service did not provide any explanation is
obvious—it believed that the ESA and contemporaneous
regulation made clear that it could not conduct a similarity of
appearance analysis for an already listed species. Further,
Friends had not raised during the rulemaking process its claim
that the Service could conduct this analysis, meaning that the
Service was not on any sort of notice that it needed to address
the issue. See Cal. Cmtys. Against Toxics v. Env’t Prot.
Agency, 928 F.3d 1041, 1049 (D.C. Cir. 2019) (“Generally, a
party must initially present its comments to the agency during
the rulemaking in order for the court to consider the issue.”)
10
(citation modified). Accordingly, Friends’ fourth procedural
argument also fails. 2
III.
We now turn to the merits. The Service contends that the
District Court erred in ruling that it had acted arbitrarily and
capriciously in refusing to consider treating the Northern DPS
of the Southern Subspecies—which was already listed as
threatened—as an endangered species based on its similarity of
appearance to the Northern Subspecies. The dispute is
fundamentally one about statutory interpretation and whether
§ 1533(e) of the ESA confers upon the Service the authority to
treat a listed threatened species as endangered. A review of the
statutory text, contemporaneous regulation, and statutory
purpose confirms that the Service may not do so.
A.
We review the District Court’s statutory interpretation
under the APA de novo. Jazz Pharms., Inc. v. Kennedy, 141
F.4th 254, 261 (D.C. Cir. 2025). As with any statutory
interpretation issue, “we begin with the text.” Southwest
Airlines Co. v. Saxon, 596 U.S. 450, 457 (2022). In analyzing
the text, we do not only read the specific language at issue, but
2
Friends also presents an insubstantial argument based on the
distinction between the Rule’s publication date and its effective date,
arguing that although the Final Rule published on February 26, 2019
became effective without alteration one month later, a challenge to
designation decisions initiated on February 26 would be unripe while
a challenge lodged a month later would not be. Such an argument
clearly fails under our precedent. See Humane Soc’y of the United
States v. U.S. Dep’t of Agriculture, 41 F.4th 564, 571–72 (D.C. Cir.
2022) (holding that a Rule’s publication date is the date that it
becomes “law even if it sets a future effective date”).
11
must also consider the language in the context of the entire
statute. Noble v. Nat’l Ass’n of Letter Carriers, AFL-CIO, 103
F.4th 45, 50 (D.C. Cir. 2024). Here, § 1533(e) means what it
plainly says—that the Service can only conduct a similarity of
appearance analysis for a species that is not already listed as
endangered or threatened.
The text of the statute provides as follows:
The Secretary may, by regulation of commerce or taking,
and to the extent he deems advisable, treat any species as
an endangered species or threatened species even though
it is not listed pursuant to this section if he finds that—
A) such species so closely resembles in appearance,
at the point in question, a species which has been
listed pursuant to such section that enforcement
personnel would have substantial difficulty in
attempting to differentiate between the listed and
unlisted species;
B) the effect of this substantial difficulty is an
additional threat to an endangered or threatened
species; and
C) such treatment of an unlisted species will
substantially facilitate the enforcement and further
the policy of this chapter.
16 U.S.C. § 1533(e).
The first part of § 1533(e) appears to grant broad authority
to the Service to “treat any species” as endangered or
threatened “even though it is not listed pursuant” to the rest of
the ESA. 16 U.S.C. § 1533(e). The plain meaning of the term
12
“any” is expansive and, read in isolation, suggests that the
Service may treat “any” species as endangered or threatened,
regardless of its inclusion on either of those lists. See Bostock
v. Clayton Cnty., 590 U.S. 644, 654 (2020) (providing that a
statute should be interpreted “in accord with the ordinary
public meaning of its terms at the time of its enactment.”)
But statutory construction is a “holistic endeavor.” United
Sav. Ass’n of Tex. v. Timbers of Inwood Forest Assocs., Ltd.,
484 U.S. 365, 371 (1988). Therefore, we must interpret “any
species” in conjunction with the ensuing textual qualifier “even
though it is not listed.” 16 U.S.C. § 1533(e). The plain
meaning—and the best reading—of this sentence is thus that
the Service can treat as endangered or threatened “any species”
that is “not listed.” An examination of the three conditions that
must be satisfied before the Service can invoke its authority
under § 1533(e) underscores our conclusion. Prior to treating
“any species” as endangered or threatened, the Service must
first determine that: (A) “such species so closely resembles in
appearance . . . a species which has been listed pursuant to such
section that enforcement personnel would have substantial
difficulty in attempting to differentiate between the listed and
unlisted species;” (B) “the effect of this substantial difficulty”
poses a threat to the “endangered or threatened species;” and
(C) “such treatment of an unlisted species will substantially
facilitate the enforcement and further the policy of” the statute.
16 U.S.C. § 1533(e)(A)–(C) (emphases added). The conditions
enumerated in (A) and (C), which expressly refer to “unlisted
species,” demonstrate that Congress intended to confer
authority on the Service to treat an unlisted species as if it were
a listed species. 3 And even though subsection (B) uses no such
3
The District Court found that interpreting “any” species as being
limited by “even though” would render the word “any”
“superfluous.” J.A. 065. Not so. Reading § 1533(e)’s qualifying
13
analogous language, the fact that it highlights the “effect of this
substantial difficulty” posing an “additional threat to an
endangered or threatened species” further demonstrates that
Congress was concerned about the effect an unlisted species
would have on a listed species. Id. § 1533(e)(B).
Friends posits that the word “unlisted” carries a different
meaning. It argues that the term is an “easy shorthand
differentiator[] from the species justifying the similarity of
appearance treatment.” Appellee Br. at 40. But that
convoluted reading is inconsistent with the plain meaning of
“unlisted,” namely, “not appearing upon a list.” Webster’s New
Int’l Dictionary of the English Language 2503 (3d ed. 1966).
Further, in the context of the ESA, which throughout uses the
word “listed” as a term of art to refer to those species that are
on the “list” of endangered species or on the “list” of threatened
species, “not listed” plainly refers to those species that are
neither on the endangered species list, nor the threatened
species list. See, e.g., 16 U.S.C. § 1532(5)(A)–(B) (defining
the term “critical habitat” in relation to those species that are
“listed in accordance with the provisions of section 1533” or
“now listed as threatened or endangered”); id. § 1533(c)(1)
(“The Secretary of the Interior shall publish in the Federal
Register a list of all species determined . . . to be endangered
species and a list of all species determined . . . to be threatened
species.”); id. § 1538(a)(1) (“[W]ith respect to any endangered
species of fish or wildlife listed pursuant to section 1533.”).
Reading the word “unlisted” as Friends suggests would be an
phrase—“even though it is not listed”—to cabin the term “species”
to unlisted species does not deprive “any” of meaning. It simply
defines the category to which “any” applies as unlisted species rather
than all species. The term “any” ensures that all members of that
defined category are covered. Accordingly, our interpretation
provides all terms their ordinary meaning, with none read out of the
statute.
14
awkward subversion of that term, especially when considering
how “listed” has been used throughout the ESA. See Azar v.
Allina Health Servs., 587 U.S. 566, 576 (2019) (holding that
when Congress “uses a term in multiple places within a single
statute, the term bears a consistent meaning throughout”).
In sum, the text of §1533(e) unambiguously illustrates that
the Service is allowed to treat an unlisted species as endangered
or threatened, but it does not empower the Service to conduct
a similarity of appearance analysis on an already listed
species. 4
B.
The above conclusion is bolstered by the Service’s
regulations. Two years after the passage of the ESA, the
Service issued regulations interpreting the statute, including 50
C.F.R. § 17.50, which implemented § 1533(e). The Service’s
longstanding interpretation of the statute, codified in regulation
and issued contemporaneously with the ESA itself “can inform
4
The ESA was passed in 1973, and the legislative history’s
references to “unlisted” species further support our interpretation.
For instance, the Senate Report underscored that “[i]f one species is
listed under [§ 1533(e)], but the other is not,” then the Service “may
treat the unlisted species as an endangered or threatened species.” S.
REP. NO. 93-307 at 9, Endangered Species Act of 1973 (July 1, 1973)
(emphases added). The House Report likewise highlighted that “[i]f
the enforcement agencies are confronted by a situation in which they
cannot adequately distinguish between listed and nonlisted species
of animals, they are authorized to ban the importation of ‘look-
alikes.’” H.R. REP. NO. 93-412, at 12, Endangered Species Act of
1973 (July 1, 1973) (emphases added). These reports demonstrate
that upon passage of the ESA, Congress was only contemplating the
authority of the Service to treat as endangered or threatened a species
that was not already on a list.
15
a court’s determination of what the law is.” Loper Bright
Enters. v. Raimondo, 603 U.S. 369, 386 (2024) (citation
modified). Here, the Service’s contemporaneous regulation
states that “[w]henever a species which is not Endangered or
Threatened closely resembles an Endangered or Threatened
species, such species may be treated as either Endangered or
Threatened[.]” 50 C.F.R. § 17.50(a). While Friends posits that
this language is ambiguous, arguing that it “can . . . easily be
read as clarifying that even unlisted species may be treated as
threatened or endangered pursuant to” § 1533(e), such a
reading is not in accordance with the plain meaning of the text.
Appellee Br. at 46. Indeed, no such “clarification” is needed
because the terms “Endangered” and “Threatened” are defined
in 50 C.F.R. § 17.3 as species that are “listed.” This
contemporaneously promulgated regulation thus underscores
what the text of the statute already states—that the Service is
authorized to conduct a similarity of appearance analysis for an
unlisted species. Nothing in the text of the statute or the
contemporaneous regulation authorizes the Service to conduct
a similarity of appearance analysis for a “listed” species.
Finally, we turn to the purpose of the statute. The District
Court below found that it would be a “strange” result if the
Service was “prohibited . . . from enacting stronger
protections for an endangered species if it found a visually
identical species was at slightly less risk of imminent
extinction.” J.A. 065. Maybe so—it is somewhat confounding
why Congress would intend the Service to have the power to
take any species not listed and treat that species as endangered
or threatened, but not the power to merely uplist a species
already listed. However, it ultimately changes nothing. As the
Supreme Court has held, statutory purpose cannot trump
statutory text. Southwest Airlines, 596 U.S. at 463.
Furthermore, Congress granted the Secretary the authority,
when “necessary and advisable to provide for the conservation
16
of” a threatened species, to promulgate regulations granting
additional protections to that threatened species that are akin to
the protections conferred upon endangered species. See 16
U.S.C. § 1533(d). Thus, the statutory purpose to protect and
conserve all threatened species is still fulfilled by our
construction of the ESA.
IV.
For the foregoing reasons, we reverse the District Court’s
grant of summary judgment in favor of Friends based on its
finding that the Service acted arbitrarily and capriciously in
refusing to conduct a similarity of appearance analysis for an
already listed species under § 1533(e) of the ESA.
So ordered.