American Wildlands v. Kempthorne

United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued April 4, 2008 Decided July 8, 2008

No. 07-5179

AMERICAN WILDLANDS, ET AL.,
APPELLANTS

v.

DIRK KEMPTHORNE, SECRETARY, U.S. DEPARTMENT OF THE
INTERIOR AND DALE HALL, DIRECTOR, U.S. FISH AND
WILDLIFE SERVICE,
APPELLEES
______

Appeal from the United States District Court
for the District of Columbia
(No. 05cv01043)

Abigail M. Dillen argued the cause for appellants. With her
on the briefs was Timothy J. Preso. Douglas L. Honnold entered
an appearance.

Lane M. McFadden, Attorney, U.S. Department of Justice,
argued the cause for appellees. With him on the briefs were
Andrew C. Mergen and Jennifer L. Scheller, Attorneys.

Before: SENTELLE, Chief Judge, and GARLAND and
GRIFFITH, Circuit Judges.
 2

Opinion for the court filed by Circuit Judge GRIFFITH.

GRIFFITH, Circuit Judge: The westslope cutthroat trout has
historically inhabited rivers and streams across parts of
Montana, Wyoming, Idaho, Oregon, and Washington. Its
scientific name, Oncorhynchus clarki lewisi, pays homage to
Lewis and Clark, the storied explorers who encountered the fish
in 1805 at the Great Falls of the Missouri River. Plaintiffs
maintain that interbreeding with other members of the trout
family — a phenomenon called hybridization — has so
imperiled the continued existence of the fish that the
government should list it as threatened under the Endangered
Species Act.

On appeal, plaintiffs argue that the government’s decision
not to do so was arbitrary and capricious because the agency
included in its count of westslope cutthroat trout hybridized fish,
which embodied the menace at issue. Plaintiffs also appeal the
district court’s denial of their motion to supplement the record
with letters supporting their case. Although new data might
require a future listing of the fish as threatened, we conclude the
agency engaged in reasoned decisionmaking based on the best
available science, and the district court did not abuse its
discretion in refusing to supplement the record.

I.

A.

The Endangered Species Act (“ESA”), 16 U.S.C. §§ 1531
et seq., requires the Secretary of the Interior to determine
whether any species is “threatened” or “endangered,” id.
§ 1533(a)(1), a responsibility he has delegated to the
Department of the Interior’s Fish and Wildlife Service
 3
(“Service”), 50 C.F.R. § 402.01(b). In determining whether to
list a species as threatened or endangered, the Service must first
define the species so the agency can estimate its population. The
ESA treats subspecies of fish as distinct species for listing
purposes. 16 U.S.C. § 1532(16).

A species is endangered when it is “in danger of extinction
throughout all or a significant portion of its range,” id.
§ 1532(6), and threatened when it is “likely to become an
endangered species within the foreseeable future throughout all
or a significant portion of its range,” id. § 1532(20). The ESA
requires the Secretary to determine whether any species is
threatened or endangered as a result of one or more identified
factors, including the catch-all, “other natural or manmade
factors affecting [the species’] continued existence.” Id.
§ 1533(a). The Secretary must make this decision “solely on the
basis of the best scientific and commercial data available to
him.” Id. § 1533(b)(1)(A). Furthermore, the ESA recognizes the
right of “interested person[s]” to petition the agency to add or
remove a species from the list, id. § 1533(b)(3)(A), and sets
forth a procedure for the agency to act on the petition and
explain its decision, id. § 1533(b)(3)–(6).

B.

In 1997 a fisherman and several environmental groups
(collectively, “American Wildlands”) petitioned the Service to
list the westslope cutthroat trout (“WCT”) as a threatened
species. See Am. Wildlands v. Norton, 193 F. Supp. 2d 244, 249
(D.D.C. 2002) (recounting procedural history). According to
plaintiffs, the chief threat to the fish comes from hybridization:
interbreeding between WCT and other members of the trout
family, primarily the rainbow trout. Plaintiffs contend that
hybridization puts at risk the genetic heritage that defines WCT
as a subspecies and that equips it to survive harsh conditions.
 4

After various delays, the Service determined not to list the
species. 65 Fed. Reg. 20,120 (Apr. 14, 2000). American
Wildlands subsequently filed suit under the Administrative
Procedure Act (“APA”), 5 U.S.C. § 706(2)(A), claiming this
decision was arbitrary and capricious because the Service
included hybridized fish in the WCT population considered for
listing. This accounting, plaintiffs argue, not only inflated the
number of WCT, but did so with the hybridized fish that
represented the very threat the proposed listing was intended to
address.

The district court granted summary judgment for the
plaintiffs, concluding:

[T]he agency wholly fails to reconcile its recognition of
hybridization as a threat to WCT’s viability with its
inclusion of hybrid stock in the population assessed for
listing. The administrative record clearly supports a
finding that hybridization is a threat to the WCT
population. . . . Therefore, when [the Service] included
hybrid stock in the population assessed for listing, it
needed to give some reasoned explanation. . . . Without
a scientifically based explanation of the decision, the
Court can not but find that the decision . . . was not
supported by the best available science, 16 U.S.C.
§ 1553(b)(1)(A) . . . .

Am. Wildlands, 193 F. Supp. 2d at 255–56. The court noted that
the Service “might have drawn a distinction between
hybridization that is a threat to a population, and hybridization
that is benign. However, [the Service] made no attempt to draw
such a distinction.” Id. at 256. The court remanded the listing
decision to the agency with instructions to reconsider and issue
a new decision within one year. Id. at 258.
 5

Following the court’s ruling, the Service announced its
intent to conduct a new status review and requested comments
from interested parties. Notice of Intent To Prepare a Status
Review for the Westslope Cutthroat Trout, 67 Fed. Reg. 56,257
(Sept. 3, 2002). The Service received numerous submissions,
including a comprehensive report on WCT populations prepared
by the fish and wildlife agencies of Idaho, Montana, Oregon,
Washington, and Wyoming, in conjunction with the U.S. Forest
Service. BRADLEY B. SHEPARD ET AL., STATUS OF WESTSLOPE
CUTTHROAT TROUT IN THE UNITED STATES: 2002 (2003)
(“Multistate Assessment”), App. 943–1042.

In August 2003 the Service again denied threatened status
to WCT. Reconsidered Finding for an Amended Petition to List
the Westslope Cutthroat Trout as Threatened Throughout Its
Range, 68 Fed. Reg. 46,989 (Aug. 7, 2003) (“Reconsidered
Finding”). The Reconsidered Finding included a general policy
statement, in which the Service provided the explanation
lacking in its earlier decision for why it included some
hybridized fish in its count of WCT, and the actual status
review, in which the Service explained its decision not to list
WCT. The policy statement began with the claim that the
scientific criteria for classifying species of fish “are based
almost entirely on morphological characters.” Id. at 46,992.
“Morphology” is “a branch of biology that deals with the form
and structure of animals and plants.” WEBSTER’S THIRD NEW
INTERNATIONAL DICTIONARY 1471 (1981). WCT have a number
of morphological characteristics that scientists use to identify
the fish, such as a distinctive spotting pattern, coloring, and a
typical number of vertebrae, scales, and bony projections called
“gill rakers.” See ROBERT J. BEHNKE, NATIVE TROUT OF
WESTERN NORTH AMERICA 77–79 (1992), App. 181–83. In
determining what fish should count as WCT, the Service relied
on morphology as the “principal criterion” and did not consider
 6
fish that conformed morphologically to WCT to pose a threat of
hybridization. 68 Fed. Reg. at 46,994.

The Service recognized, however, that genetic data allows
biologists to detect “introgression” — the “entry or introduction
of a gene from one gene complex into another,” WEBSTER’S
THIRD NEW INTERNATIONAL DICTIONARY 1187 (1981) — in fish
that otherwise conform morphologically to the subspecies. 68
Fed. Reg. at 46,992. As a result, when genetic data is available,
scientists can now detect hybridization in some instances when
they previously could not by relying on morphology alone.
When using genetic data to classify fish, the Service adopted a
rule: “[F]or populations for which molecular genetic data may
be the only data available, populations with less than 20 percent
introgression will be considered WCT under the [ESA], whereas
populations with more than 20 percent introgression will
generally be excluded from the WCT subspecies.” Id. at 46,995.
The Service settled on the 20% threshold after reviewing the
scientific evidence and concluding that “a natural population of
WCT with less than 20 percent of its genes derived from
[foreign subspecies] is, most likely, morphologically
indistinguishable from nonintrogressed populations of WCT
with no hybrid ancestry.” Id. at 46,994. The Service also
concluded that low levels of introgression can occur as a result
of the natural evolutionary process and that such fish may
“remain very valuable to the overall conservation and survival
of that species.” Id. at 46,992.

In the status review the Service analyzed the threat of
hybridization to WCT, relying on the 2002 Multistate
Assessment as the best available science. Id. at 46,999. The
Multistate Assessment identified populations of WCT within the
subspecies’ historic range and classified them according to their
actual or suspected genetic status, Multistate Assessment at 5
(introduction), 1 (main report), App. 953–54, and then
 7
according to the conservation strategy that state agencies
employed to manage the fish, id. at 3–4 (main report), 80 (App.
D), App. 956–57, 1033. The report had genetic data for
approximately 21% of habitat occupied by WCT within its
historic range. Id. at 13 (main report), App. 966.

Drawing on data from the Multistate Assessment, the
Service included in the WCT population count fish that fell into
three categories: (1) genetically tested populations with
introgression levels below 1%; (2) nongenetically tested
populations that morphologically conformed to WCT and that
scientists concluded likely had introgression levels below 1%
because no records indicated that hybridizing fish, such as
rainbow trout, were at one time stocked in the area or were
otherwise present; and (3) populations that the Multistate
Assessment classified as “conservation populations.” 68 Fed.
Reg. at 46,999. This last category included fish that
morphologically conformed to WCT and generally had less than
10% introgression. Multistate Assessment at 3–4 (main report),
80 (App. D), App. 956–57, 1033; see also UTAH DIVISION
WILDLIFE RESOURCES, GENETIC CONSIDERATIONS ASSOCIATED
WITH CUTTHROAT TROUT MANAGEMENT 4 (2000)
(“[Conservation] populations retain all the phenotypic attributes
associated with the subspecies, though they exist in a slightly
introgressed condition.”), App. 486. Conservation populations
included some fish with slightly higher levels of introgression
where the populations demonstrated a special attribute that
biologists sought to preserve, such as an evolutionary adaptation
to an extreme environmental condition. Multistate Assessment
at 3–4 (main report), App. 956–57.

Looking to the Multistate Assessment, and considering the
prospects for future genetic dilution, the Service acknowledged
that hybridization “remains the greatest threat to WCT,” 68 Fed.
Reg. at 47,006, but decided the severity of the threat did not yet
 8
require listing. Importantly, the agency identified significant
populations of nonintrogressed WCT. See id. at 47,004.

The information that we have summarized in this
document, particularly that obtained from the status
update report (Shepard et al. 2003), indicates even
greater abundance of WCT across the subspecies’ range
than we had estimated during the initial status review
(U.S. Fish and Wildlife Service 1999). Today, 563
extant WCT “conservation” populations collectively
occupy 39,349 km (24,450 mi) of stream in Idaho,
Montana, Oregon, Washington, and Wyoming. . . . In
our initial status review . . . we reported that WCT
occupied about 37,015 km (23,000 mi) of stream in the
United States. In addition, nonintrogressed WCT are
now known to inhabit 5,633 km (3,500 mi) of stream
and probably inhabit as many as 20,278 km (12,600 mi)
of stream in which no potentially hybridizing fishes
occur. In our initial status review . . . we reported that
nonintrogressed WCT were known to occupy 4,237 km
(2,633 mi) of stream.

Id. at 47,006.

The Service noted that some of these populations exist
within reach of potentially hybridizing fish, such as the rainbow
trout, yet have remained free from interbreeding. Id. The
Multistate Assessment predicted that hybridization would
continue to move upstream into areas presently occupied by
nonintrogressed WCT, although environmental factors such as
altitude, stream size, and water temperature may limit that
progression. Id. at 47,004–05. Moreover, in the case of 1525
stream miles containing pure WCT, artificial barriers would
prevent hybridization altogether. Id. at 47,005. The Service also
noted that to the degree hybridization persists, some “limited
 9
presence” of foreign genes does not preclude classification as
WCT — a point the agency made earlier in the policy section of
its Reconsidered Finding. Id. at 47,006.

Dissatisfied with the Reconsidered Finding, plaintiffs filed
another suit in district court under the APA, 5 U.S.C.
§ 706(2)(A), again claiming the agency’s decision was arbitrary
and capricious because it still counted hybridized fish in the
WCT population. This time the court granted summary
judgment for the agency because it found that record evidence
supported the agency’s decision. Am. Wildlands v. Kempthorne,
478 F. Supp. 2d 92, 99 (D.D.C. 2007).

American Wildlands filed a timely notice of appeal on May
25, 2007. In addition to challenging the decision not to list,
plaintiffs also appeal the district court’s order denying their
motion for leave to supplement the administrative record. Am.
Wildlands v. Norton, No. 05-1043, 2006 WL 2780702 (D.D.C.
Sept. 21, 2006). The district court had jurisdiction under the
ESA’s citizen suit provision, 16 U.S.C. § 1540(g), and we have
jurisdiction to hear the appeal under 28 U.S.C. § 1291.

II.

The Service’s listing determination is subject to review
under the APA and must be set aside if “arbitrary, capricious, an
abuse of discretion, or otherwise not in accordance with law.” 5
U.S.C. § 706(2)(A); see City of Las Vegas v. Lujan, 891 F.2d
927, 932 (D.C. Cir. 1989). “This standard of review is a highly
deferential one. It presumes agency action to be valid.” Ethyl
Corp. v. EPA, 541 F.2d 1, 34 (D.C. Cir. 1976). The Supreme
Court has explained that an agency acts arbitrarily or
capriciously if it “has relied on factors which Congress has not
intended it to consider, entirely failed to consider an important
aspect of the problem, offered an explanation for its decision
 10
that runs counter to the evidence before the agency, or is so
implausible that it could not be ascribed to a difference in view
or the product of agency expertise.” Motor Vehicle Mfrs. Ass’n
v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43 (1983).
Because the district court ruled on summary judgment, our
review is de novo. See Castlewood Prods., L.L.C. v. Norton, 365
F.3d 1076, 1082 (D.C. Cir. 2004).

American Wildlands presents several arguments, each of
which concludes that the Service’s decision not to list WCT was
arbitrary and capricious. We disagree.

A.

American Wildlands’ primary challenge is to the Service’s
reliance on morphological data, which they argue was arbitrary
and capricious because the agency wrongly assumed that fish
morphologically conforming to WCT will be only slightly
hybridized. They contend that evidence in the record shows that
fish can have introgression levels up to 50% and still
morphologically conform to the subspecies. See, e.g., F.W.
Allendorf et al., Intercrosses and the U.S. Endangered Species
Act: Should Hybridized Populations be Included as Westslope
Cutthroat Trout? 7 (2003) (unpublished manuscript), App. 925.
“In practice, this means that every last surviving population of
[WCT] could be up to 50 percent hybridized before [the
Service] would recognize hybridization as a major concern in
the ESA listing context.” American Wildlands’ Opening Br. at
40. This argument, plaintiffs maintain, belies the government’s
assurance that “individual fish conforming morphologically to
the scientific taxonomic description of WCT” will carry foreign
genes at a “low frequency.” 68 Fed. Reg. at 46,994. Plaintiffs
argue that even if the Service reasonably included fish having
less than a 20% introgression level in the WCT population when
genetic data was available, the agency arbitrarily assumed that
 11
populations for which genetic data was not available would also
have introgression levels below 20% if they morphologically
conformed to WCT.

The Service concedes that its method may count some fish
in the WCT population that morphologically conform to WCT
but have introgression levels higher than 20%. See Service’s Br.
at 37 (“One of the primary authors of the Service’s Finding has
acknowledged this possibility, and the Service is well aware of
it.”); Oral Arg. Recording at 22:10–22:36. Nonetheless, the
agency argues that its method is reasonable. We agree and hold
that in the absence of genetic data the Service reasonably
included fish morphologically conforming to WCT in the
population considered for listing. Under the ESA, listing
determinations are to be made “solely on the basis of the best
scientific and commercial data available.” 16 U.S.C.
§ 1533(b)(1)(A). In Southwest Center for Biological Diversity v.
Babbitt, we held that “[t]he ‘best available data’ requirement
makes it clear that the Secretary has no obligation to conduct
independent studies.” 215 F.3d 58, 60 (D.C. Cir. 2000). Rather,
that provision “ ‘merely prohibits the Secretary from
disregarding available scientific evidence that is in some way
better than the evidence he relies on.’ ” Id. (quoting City of Las
Vegas, 891 F.2d at 933) (emphasis added).

The “best available data” requirement in § 1533(b)(1)(A)
requires not only that data be attainable, but that researchers in
fact have conducted the tests. Genetic testing is a relatively new
technique for classifying fish and though it can provide
precision in determining introgression levels not possible on the
basis of morphology alone, genetic data is not available for the
large majority of WCT populations. Lacking genetic data, the
Service did not unreasonably rely on morphological data to
classify fish — even though, by the agency’s admission, some
fish counted as WCT may have introgression levels greater than
 12
20%. Aside from morphological assessments and absent genetic
data, the Service had nothing else upon which to rely.

At oral argument, American Wildlands asserted that the
Service should “look at the genetically pure populations, . . .
look at the threat facing those [populations], and . . . decide
whether those populations . . . would be able to sustain the
species in the future.” Oral Arg. Recording at 13:20–13:30. To
agree with the plaintiffs would be to require the Service to make
its decision only on the basis of genetic data. This rule would
demand the absurd result that the Service must deem threatened
any species for which it lacks genetic data. Absent a statutory
mandate requiring the Service to collect genetic data, however,
the Service’s method was reasonable. If plaintiffs believe the
Service’s decision not to list WCT depended on counting fish
which, if genetically tested, would have introgression levels
greater than 20%, the path for plaintiffs to press their argument
is clear: provide sufficient genetic data to substantiate this
claim.

American Wildlands also argues that even if the Service
reasonably relied on morphological data in some instances, the
agency violated the law by relying on such data when genetic
information was in fact available. That the plaintiffs make this
argument in their opening brief is understandable. In its
Reconsidered Finding, the Service stated that morphology
would serve as the “principal criterion” for classifying fish as
WCT and then stated, “[F]or populations for which molecular
genetic data may be the only data available, populations with
less than 20% introgression will be considered WCT under the
Act.” 68 Fed. Reg. at 46,995 (emphasis added). The plaintiffs
were not unreasonable in interpreting this statement to mean the
Service would only use genetic data when morphological data
was not available.
 13
In its brief, however, the Service made clear that in
conducting its status review it always used genetic data when
available and never included fish in the WCT population count
that carried introgression levels greater than 20%. See Service’s
Br. at 39 (“[M]olecular genetic data was used whenever
available, and populations of fish with higher than 20% genetic
introgression were rejected for classification as westslope
cutthroat trout.”); id. at 39 n.10 (explaining that in conducting
the status review the Service never encountered a population for
which it had both morphological data and genetic data showing
fish with introgression levels greater than 20%). At oral
argument, the government was even more firm:

[COURT]: “So we’ve settled that if you have genetic
data as well as morphology, you will not ignore the
genetic data.”

[SERVICE]: “Correct.”

Oral Arg. Recording at 21:52–22:01. Although our decision
might be different if the Service had refused to rely on available
genetic data, that did not happen here.

B.

Plaintiffs also challenge the agency’s decision to include
fish in the WCT population count having introgression levels as
high as 20%. When pressed at oral argument, American
Wildlands would not identify a threshold introgression level.
See Oral Arg. Recording at 16:13–17:17, 38:50–42:50. And in
their briefs, plaintiffs argue that the best available science does
not deem any level of introgression benign.

To support this claim, plaintiffs point to a scientific paper in
the record suggesting that introgression always risks the loss of
 14
genetic diversity, which in turn can reduce resistance to disease
and diminish an organism’s ability to adapt to changing
environmental conditions. See F.W. Allendorf & R.F. Leary,
Conservation and Distribution of Genetic Variation in a
Polytypic Species, the Cutthroat Trout, CONSERVATION
BIOLOGY 170, 180 (1988), App. 89. In addition, plaintiffs point
to a paper which they argue establishes that fish bearing low
levels of introgression and morphologically conforming to WCT
may nonetheless display behavioral differences. See N. Hitt,
Hybridization Between Westslope Cutthroat Trout and Rainbow
Trout: Distribution and Limiting Factors (2002) (unpublished
master’s thesis), App. 626–713. In particular, they contend, Hitt
shows that “slightly hybridized fish are dispersing and
colonizing new territory at rates that are atypical of [WCT] in
Montana’s Flathead River System. Notably, these are fish that
are hybridized at low levels that [the Service] deemed to be
benign.” American Wildlands’ Opening Br. at 43 (citation
omitted). This tendency is referred to as “straying.”

Because we have held that the Service was reasonable to
count as WCT fish that morphologically conformed to the
subspecies when the agency lacked genetic data, we consider
this challenge only in those instances where the Service had
genetic data. We conclude the agency did not act arbitrarily or
capriciously by including fish with introgression levels below
20%.

As an initial matter, record evidence supports the
conclusion that fish having less than 20% foreign genes are
morphologically indistinguishable from nonintrogressed
populations. See, e.g., 68 Fed. Reg. at 46,993–94 (citing
sources). Moreover, scientific papers in the record suggest that
low levels of introgression may, in fact, make a positive
contribution to the long-term survival of a subspecies. For
example, a peer review of another article by Allendorf, which
 15
article made the same claim about the harmful effects of any
hybridization, warned that some of the paper’s statements on
this issue amounted to “speculation” and suggested that low
levels of genetic introgression could allow WCT to better adapt
to extreme environmental conditions, such as fires, floods, or
droughts. D. Campton, Peer Review of Draft Report by F.W.
Allendorf and L.L. Lundquist, Hybridization, Fitness, and
Conservation of Westslope Cutthroat Trout (2002), App. 861.
Likewise, the Hitt paper did not draw a conclusion based on
evidence, but only suggested further research. Hitt,
Hybridization Between Westslope Cutthroat Trout and Rainbow
Trout 53 (“[T]he effects of [rainbow trout] introgression on
straying rates should be assessed. . . . [Rainbow trout]
introgression could introduce a genetic predisposition to
stray. . . . To test this hypothesis, one would first have to
determine . . . . ”) (emphasis added), App. 686.

Under these circumstances, we defer to the agency’s
decisionmaking. “The rationale for deference is particularly
strong when the [agency] is evaluating scientific data within its
technical expertise: ‘[I]n an area characterized by scientific and
technological uncertainty[,] . . . this court must proceed with
particular caution, avoiding all temptation to direct the agency
in a choice between rational alternatives.’ ” Int’l Fabricare Inst.
v. EPA, 972 F.2d 384, 389 (D.C. Cir. 1992) (quoting Envtl. Def.
Fund v. Costle, 578 F.2d 337, 339 (D.C. Cir. 1978)); see also
Balt. Gas & Elec. Co. v. Natural Res. Def. Council, 462 U.S. 87,
103 (1983) (noting that a reviewing court must be “at its most
deferential” when examining conclusions made “at the frontiers
of science”). And again we note that in the absence of available
evidence, Congress does not require the agency to conduct its
own studies. See 16 U.S.C. § 1533(b)(1)(A); Sw. Ctr. for
Biological Diversity v. Babbitt, 215 F.3d 58, 60 (D.C. Cir.
2000). Where the agency used genetic data, we defer to the
 16
Service’s decision to include fish in the listing population
having introgression levels below 20%.

C.

American Wildlands further argues that the Service’s policy
of including some introgressed fish in the WCT count is an
arbitrary departure from past practice. In at least one previous
listing determination, plaintiffs aver, the Service only counted
fish as members of the subspecies considered for listing when
they had introgression levels below 1%. American Wildlands’
Reply Br. at 22 (citing Candidate Status Review for Rio Grande
Cutthroat Trout, 67 Fed. Reg. 39,936 (June 11, 2002)).

We need not consider this argument because plaintiffs have
forfeited it on appeal, having raised it for the first time in their
reply brief. See Rollins Envtl. Servs. v. EPA, 937 F.2d 649, 652
n.2 (D.C. Cir. 1991) (“Issues may not be raised for the first time
in a reply brief.”). In the statement of facts section of its opening
brief, American Wildlands did explain that in a past assessment
the Service only counted fish as Rio Grande Cutthroat Trout
having less than 1% introgression. American Wildlands’
Opening Br. at 23–25. But explaining the factual basis in the
opening brief for an argument not made until the reply brief is
insufficient to raise the claim. See Karst Envtl. Educ. & Prot.,
Inc. v. EPA, 475 F.3d 1291, 1299 (D.C. Cir. 2007); PDK Labs.,
Inc. v. U.S. Drug Enforcement Admin., 438 F.3d 1184, 1196
(D.C. Cir. 2006).

The only place where plaintiffs mention the argument in
their opening brief is at the very end of the section addressing
the agency’s decision in the Reconsidered Finding, where they
state:
 17
[T]he [ESA] does not permit [the Service] to continue
using inaccurate data simply because it is more
convenient to do so — particularly when the agency has
at its disposal the principled genetic criteria developed
for the Rio Grande cutthroat trout listing. See id.; see
also, e.g., Friends of the Wild Swan, 12 F. Supp. 2d at
1135 (finding the [Service] violated the [ESA] in
ignoring the most reliable data and further stressing that
“[a]n agency acts arbitrarily when it departs from its
precedent without giving good reason”) (citing
Northern California Power Agency v. F.E.R.C., 37 F.3d
1517, 1522 (9th Cir. 1994)).

American Wildlands’ Opening Br. at 48 (emphasis added; all
brackets added except final set). A fleeting statement in the
parenthetical of a citation is no more sufficient to raise a claim
than a cursory remark in a footnote, which we have consistently
rejected. See, e.g., Hutchins v. District of Columbia, 188 F.3d
531, 539 n.3 (D.C. Cir. 1999) (“We need not consider cursory
arguments made only in a footnote . . . . ”); see also Wash. Legal
Clinic for the Homeless v. Barry, 107 F.3d 32, 39 (D.C. Cir.
1997) (“Because the District raises this issue in such a cursory
fashion, we decline to resolve it.”) (internal quotation marks
omitted); Ry. Labor Executives’ Ass’n v. U.S. R.R. Ret. Bd., 749
F.2d 856, 859 n.6 (D.C. Cir. 1984) (declining to resolve an issue
that “consisted of only three sentences in the [appellant’s] brief
and no discussion of the . . . relevant case law”).

III.

Lastly, American Wildlands appeals the district court’s
denial of its motion to supplement the record with two letters
from scientists whose work the Service considered in deciding
not to list WCT. We review the district court’s refusal to
supplement the administrative record for abuse of discretion.
 18
Novartis Pharm. Corp. v. Leavitt, 435 F.3d 344, 348 (D.C. Cir.
2006).

When reviewing agency action under the APA, we review
“the whole record or those parts of it cited by a party.” 5 U.S.C.
§ 706. The record consists of the order involved, any findings or
reports on which that order is based, and “the pleadings,
evidence, and other parts of the proceedings before the agency.”
FED. R. APP. P. 16(a). Ordinarily, “review is to be based on the
full administrative record that was before the Secretary at the
time he made his decision.” Citizens to Preserve Overton Park,
Inc. v. Volpe, 401 U.S. 402, 420 (1971); see also Walter O.
Boswell Mem’l Hosp. v. Heckler, 749 F.2d 788, 792 (D.C. Cir.
1984). We do not allow parties to supplement the record “unless
they can demonstrate unusual circumstances justifying a
departure from this general rule.” Tex. Rural Legal Aid, Inc. v.
Legal Servs. Corp., 940 F.2d 685, 698 (D.C. Cir. 1991). We
have recognized such circumstances in at least three instances,
see James Madison Ltd. by Hecht v. Ludwig, 82 F.3d 1085,
1095 (D.C. Cir. 1996) (collecting cases): (1) “[T]he agency
deliberately or negligently excluded documents that may have
been adverse to its decision,” id.; (2) “the district court needed
to supplement the record with ‘background information’ in
order to determine whether the agency considered all of the
relevant factors,” id.; or (3) “the agency failed to explain
administrative action so as to frustrate judicial review,” id.
(internal quotation marks and brackets omitted).

We hold the district court did not abuse its discretion in
denying the motion to supplement the record. Both letters were
written after the Service issued its Reconsidered Finding, and
are therefore not part of the administrative record. Moreover,
they do not satisfy any of the “unusual circumstances”
previously listed. Rather, as the district court correctly
concluded, Am. Wildlands v. Norton, No. 05-1043, 2006 WL
 19
2780702, at *2–4 (D.D.C. Sept. 21, 2006), they merely disagree
with the Service’s conclusions, see, e.g., Letter from N.P. Hitt,
Professor, Dept. of Fisheries & Wildlife Scis., Va. Polytechnic
Inst. & State Univ., to L.R. Keading, Chief, Branch of Native
Fishes Mgmt. (July 10, 2004), reprinted at App. 1120 (“[W]e
disagree with the [Service’s] interpretation of our data on
several counts and believe that the current introgression policy
does not represent the best available scientific information.”).

IV.

Because American Wildlands has not shown that the
Service’s decision to deny listing the westslope cutthroat trout
as a threatened species was arbitrary or capricious, and because
plaintiffs have not shown that the district court abused its
discretion in denying the motion to supplement the record, we
affirm the district court in all respects.

So ordered.