Court Opinion

ID: 9906583
Source: CourtListenerOpinion
Date Created: 2023-12-04 18:01:22.824543+00
Date Added: 2024-06-11T09:25:14.683833
License: Public Domain

FOR PUBLICATION

   UNITED STATES COURT OF APPEALS
        FOR THE NINTH CIRCUIT

CENTER FOR BIOLOGICAL                      No. 22-15809
DIVERSITY; MARICOPA
AUDUBON SOCIETY; SIERRA                   D.C. No. 4:20-cv-
CLUB, Grand Canyon Chapter,                 00106-RCC

               Plaintiffs-Appellants,
                                             OPINION
 v.

DEBRA HAALAND, in her official
capacity as Secretary of the Interior;
UNITED STATES FISH AND
WILDLIFE SERVICE; MARTHA
WILLIAMS, in her official capacity as
the Director of FWS; AMY
LUEDERS, in her official capacity as
Regional Director of the FWS
Southwest Region; LLOYD J.
AUSTIN III, in his official capacity as
Secretary of Defense; CHRISTINE E.
WORMUTH, in her official capacity
as Secretary of the Army; ANTHONY
R. HALE, in his official capacity as
the Senior Commander of Fort
Huachuca,

               Defendants-Appellees.
2          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

        Appeal from the United States District Court
                 for the District of Arizona
         Raner C. Collins, District Judge, Presiding

             Argued and Submitted May 16, 2023
                      Phoenix, Arizona

                    Filed December 4, 2023

    Before: Jacqueline H. Nguyen, Daniel P. Collins, and
              Kenneth K. Lee, Circuit Judges.

                     Opinion by Judge Lee;
             Partial Concurrence by Judge Collins

                          SUMMARY *

                   Endangered Species Act

    In an action brought by environmental organizations
challenging a U.S. Fish and Wildlife Service Biological
Opinion (BiOp) concerning the use of water from the San
Pedro River Basin in Arizona, the panel vacated the BiOp,
reversed the district court’s summary judgment for the
government on the Preserved Petrified Forest easement, and
remanded with instructions for the Service and the U.S.
Army to reevaluate its water-savings analysis in a new
biological opinion.

*
 This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND          3

    The U.S. Army pumps and uses water from the San
Pedro River Basin, which also houses several plant and
animal species protected under the Endangered Species
Act. To compensate for the water use, the federal
government proposed a conservation easement—a promise
not to use nearby land for water-intensive agricultural
purposes—that would hypothetically save water and not
jeopardize wildlife that depend on the basin.
    The panel agreed with plaintiffs’ contention that the
Service’s BiOp lacked evidence to support its water-savings
analysis. The panel held that the government must show that
the benefit from the conservation easement would be
“reasonably certain” under the relevant regulations. Here,
the government provided little evidence and relied mostly on
speculation to claim water savings. Consequently, the
government’s no-jeopardy determination about the protected
wildlife was arbitrary and capricious.
     The panel further held that the government’s conclusion
that the reduction in the baseflow of the Babocomari River
(a tributary of the San Pedro River) would not jeopardize the
northern Mexican gartersnake was not arbitrary and
capricious, and thus the issue need not be reconsidered on
remand.
    Judge Collins concurred in part and concurred in the
judgment. He concurred in the majority’s judgment to the
extent that it partially reversed and remanded to the district
court with instructions to remand for preparation of a new
BiOP that rested on a revised water-savings analysis, but
would reach that conclusion on narrower grounds than the
majority. He concurred in Part II of the court’s opinion,
which rejected plaintiffs’ further contentions that are
4         CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

specific to the government’s challenged determinations as to
the northern Mexican gartersnake.

                       COUNSEL

Stuart Gillespie (argued), Heidi McIntosh, and Thomas
Delehanty, Earthjustice, Denver, Colorado, for Plaintiffs-
Appellants.
John E. Bies (argued), Andrew C. Mergen, and Rachel
Heron, Attorneys; Todd Kim, Assistant Attorney General;
Environment and Natural Resources Division, United States
Department of Justice, Washington, D.C.; Benhamin Hillner
and Mark Holycross, Attorneys, United States Department
of the Army, Washington, D.C.; Kim Bannerman, Attorney,
Fish and Wildlife Service, United States Department of the
Interior, Albuquerque, New Mexico; for Defendants-
Appellees.
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND         5

                        OPINION

LEE, Circuit Judge:

    Water is a vital resource for humans and wildlife alike.
At Fort Huachuca in Arizona, the U.S. Army pumps and uses
water from the San Pedro River Basin. But that basin also
houses several plant and animal species protected under the
Endangered Species Act (ESA), 16 U.S.C. §§ 1531–44. To
compensate for this water use, the federal government
proposed (among other things) a “conservation easement”—
a promise not to use nearby land for water-intensive
agricultural purposes—that would hypothetically save water
and thus not jeopardize wildlife that depend on the basin.
    The Center for Biological Diversity (CBD) brings this
challenge under the Administrative Procedure Act (APA), 5
U.S.C. §§ 551–59, contending that the U.S. Fish and
Wildlife Service’s biological opinion (BiOp) lacks evidence
to support its water-savings analysis.
    We agree with CBD. We hold that the government must
show that the benefit from the conservation easement would
be “reasonably certain” under the relevant regulations.
While the ESA does not impose a high bar to claim
conservation benefits, the government here provided little
evidence and relied mostly on speculation to claim water
savings. And because the government cannot claim these
water savings, its no-jeopardy determination about the
protected wildlife is arbitrary and capricious. We thus
reverse the district court’s partial summary judgment for the
government and remand for the government to reassess in a
new BiOp.
6         CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

    CBD also challenges the government’s conclusion that
the reduction in the baseflow of the Babocomari River (a
tributary of the San Pedro River) will not jeopardize the
northern Mexican gartersnake. The district court did not
address this issue, but we conclude that the agency’s
decision was not arbitrary and capricious. It thus need not
be reconsidered on remand.
                     BACKGROUND
I. Statutory and Regulatory Background
     The ESA directs the U.S. Fish and Wildlife Service (the
Service) to develop a list of threatened or endangered species
as well as a list of critical habitats for those species. 16
U.S.C. § 1533(a). It then requires each federal agency to
“insure,” in consultation with the Service, that “any action
authorized, funded, or carried out by such agency . . . is not
likely to jeopardize the continued existence of” any listed
species or destroy or adversely modify their designated
critical habitat. Id. § 1536(a)(2).
    To comply with the ESA, an agency must start by
preparing a biological assessment of a proposed action’s
impact on any listed species and their critical habitats. 50
C.F.R. § 402.12 (2009). If the biological assessment
concludes that the proposed action is likely to harm the
species or habitats, the agency will consult the Service,
which will then issue a BiOp. 50 C.F.R. § 402.14; 16 U.S.C.
§ 1536(a)(2). In the BiOp, the Service provides the final
determination of whether the proposed action is likely to
“jeopardize the continued existence of” any listed species or
            CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND                 7

destroy or adversely modify critical habitats. 50 C.F.R.
§ 402.14(h)(1)(iv). 1
II. Factual Background
    A. Fort Huachuca pumps water from the San Pedro
       River Valley.
    Fort Huachuca is a major Army garrison in the Upper
San Pedro River Basin of southeastern Arizona. The river
basin is also home to four listed species or species proposed
for listing: the Huachuca water umbel, the northern Mexican
gartersnake, the western yellow-billed cuckoo, and the
southwestern willow flycatcher.
    The Fort pumps groundwater from this river basin. But
to limit the impact on the river basin and ultimately the
protected species, the Fort has pursued various mitigation
measures.     These include the development of water
conservation programs and methods to capture and return
water to the basin. The Fort has also obtained water
conservation easements, which limit water use by restricting
agricultural and residential development.
    B. The Service in its BiOp credits water savings and
       finds no jeopardy for wildlife and their habitat.
   Because the Fort’s pumping could threaten the protected
species and their habitat, the Army engaged in the
consultation and assessment requirements of the ESA. The
Army has faced multiple rounds of litigation over the impact

1
 Technically, a BiOp examines the effects of an agency action on listed
species, while the effects on proposed species are examined in a
conference opinion. See 50 C.F.R. § 402.10. The Service included its
BiOp and conference opinion in the same document, so we treat the
opinions as one.
8          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

of the Fort’s pumping, but this appeal concerns the
environmental assessment that began with the Army’s
Programmatic Biological Assessment (PBA) from May
2013 and concluded with the Service’s BiOp from March
2014.
    The PBA set out to determine how the Fort’s pumping
affected the river basin’s groundwater and in turn the
protected species and their habitat. First, it conducted a
“groundwater demand accounting,” which balances the
amount of water used by the Fort against the amount that the
Fort returns to the groundwater through recharge measures
and water savings. In 2012, the PBA observed that the Fort
had a net groundwater demand of -1,180 acre-feet (AF). 2
But the PBA estimated that, beginning in 2014, the Fort
would have a net groundwater surplus of at least 1,419 AF.
    The estimated water savings from the Preserve Petrified
Forest (PPF) easement contributed substantially to this
expected surplus. Even though the land at issue in the PPF
easement has remained largely dormant since 2005, the PBA
assumed that, but for the easement, someone would have
resumed agricultural irrigation on 480 acres of the land
beginning on January 1, 2014. Thus, the PBA credited the
PPF easement with 2,588 AF/year of water savings, turning
the Fort’s groundwater deficit into a surplus from 2014
onward.
    Second, the PBA employed a “groundwater flow model”
to study the effects of the Fort’s pumping. The groundwater
flow model takes the estimates for groundwater withdrawal
and recharge from the groundwater demand accounting and

2
 An acre-foot is the volume of water that would cover one acre to the
depth of one foot, or about 325,851 gallons.
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND         9

uses them as inputs to predict how the Fort’s pumping will
affect the baseflow of surrounding rivers. The model,
however, does not incorporate the groundwater demand
accounting’s predictions about the water savings from the
PPF and other water conservation easements. Even without
including the effects of water conservation easements, the
model predicted that Fort-attributable activities would boost
baseflow for some parts along the San Pedro River. But it
also predicted that the Fort would have a slight negative
impact (-.1 cubic feet-per-second) on the baseflow of the
Babocomari River.
    After completing the PBA, the Army decided to seek
formal consultation with the Service. In its BiOp, the
Service first estimated the Fort’s effect on baseflow,
incorporating the groundwater demand accounting and its
baseflow predictions from the groundwater model. The
Service then conducted its jeopardy and adverse-
modification determinations for the protected species.
Despite decreased baseflows in the Babocomari River, the
BiOp concluded that the Fort would have a minimal effect
on the protected species and therefore would not jeopardize
them or adversely modify their habitats.
   C. CBD sues the government and challenges the
      water-savings analysis.
    CBD challenged the BiOp under the APA, asserting that
the Service violated the ESA. CBD moved for summary
judgment on all its claims, and the government cross-moved.
For the most part, the district court granted summary
judgment for the government. Relevant here, the district
court rejected CBD’s claim that the Service lacked sufficient
support for its conclusion that the PPF easement would yield
water savings. Instead, the court found that it was
10         CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

reasonably likely that the land would have been used for
agricultural use but for the easement and that the Service did
not err in determining that the easement saved water.
    The district court, however, granted summary judgment
for one of CBD’s claims. The district court held that the
Service overestimated the PPF easement’s water savings
because the groundwater demand accounting glossed over
the reabsorption of water used in irrigation. Thus, the court
held that the Service’s jeopardy and adverse-modification
determinations were arbitrary and capricious. The district
court remanded for the Army and the Service to engage in
formal consultation to formulate a superseding BiOp that
addresses this issue.
   CBD timely filed this appeal, asking us to expand the
scope of issues the Service must address on remand.
                STANDARD OF REVIEW
    We review de novo a district court’s denial of summary
judgment. Karuk Tribe of Cal. v. U.S. Forest Serv., 681 F.3d
1006, 1017 (9th Cir. 2012) (en banc) (citing Russell Country
Sportsmen v. U.S. Forest Serv., 668 F.3d 1037, 1041 (9th
Cir. 2011)).
    The APA governs our review of agency decisions under
the ESA. Ctr. for Biological Diversity v. U.S. Bureau of
Land Mgmt., 698 F.3d 1101, 1109 (9th Cir. 2012) (citing
Karuk Tribe, 681 F.3d at 1017). Under the APA, an agency
action is valid unless it is “arbitrary, capricious, an abuse of
discretion, or otherwise not in accordance with law.” Id.
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND        11

(quoting 5 U.S.C. § 706(2)(A)). An agency action is
arbitrary and capricious if the agency 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 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.

Pac. Coast Fed’n of Fishermen’s Ass’ns, Inc. v. Nat’l
Marine Fisheries Serv., 265 F.3d 1028, 1034 (9th Cir. 2001)
(quoting Motor Vehicle Mfrs. Ass’n v. State Farm Mut. Auto.
Ins. Co., 463 U.S. 29, 43 (1983)).
                      DISCUSSION
I. The BiOp’s Jeopardy and Adverse-Modification
   Determinations Were Arbitrary and Capricious
   Because the Analysis of the Easement Was
   Speculative.
   A. If the groundwater demand accounting is flawed,
      we must remand.
    To start, we address the lurking interplay between and
among the groundwater demand accounting (which credited
the PPF easement’s water savings), the groundwater flow
model (which did not consider it), and the BiOp (which
included the jeopardy and adverse-modification
determinations for the protected species). Put another way,
we need to figure out if flaws in the PPF easement’s expected
water savings would cast doubt on the BiOp’s jeopardy and
adverse-modification determinations.          See Ctr. for
12         CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

Biological Diversity v. Bernhardt, 982 F.3d 723, 747 (9th
Cir. 2020) (“Our conclusion that the mitigation measures in
the BiOp are insufficiently specific to enforce has no legal
consequence unless we separately conclude that [the
Service] relied on those measures.”); see also Nat’l Ass’n of
Home Builders v. Defs. of Wildlife, 551 U.S. 644, 659 (2007)
(holding that administrative law has a harmless-error rule).
    At oral argument, the government conceded that the
BiOp relied on the groundwater demand accounting—and
thus the PPF easement’s water savings—to make its
jeopardy and adverse-modification determinations for all the
protected species at issue. We can thus jump straight to
addressing whether there are any flaws with the estimates of
the PPF easement’s water savings. If there are, that would
undermine the groundwater demand accounting and render
the jeopardy and adverse-modification determinations
arbitrary and capricious.
     B. The groundwater demand accounting was flawed
        because the PPF easement’s claimed water
        savings were not reasonably certain.
    We hold that to receive credit for the PPF easement’s
claimed water savings, the government must show that the
benefits were “reasonably certain” to occur. This standard
comes from 50 C.F.R. §§ 402.14 and 402.02, which
implement the statutory requirement for the government to
ensure that listed species are not “likely” to face jeopardy or
to have their habitat adversely modified. 16 U.S.C.
§ 1536(a)–(d). The regulation requires the Service to assess
the “effects of the action on listed species or critical habitat.”
50 C.F.R. §§ 402.14(g)(3), (h)(1)(iii). At the time the BiOp
            CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND                 13

was issued, the regulation defined the “effects of the action”
as:

        the direct and indirect effects of an action on
        the species or critical habitat, together with
        the effects of other activities that are
        interrelated or interdependent with that
        action, that will be added to the
        environmental baseline. . . . Indirect effects
        are those that are caused by the proposed
        action and are later in time, but still are
        reasonably certain to occur. Interrelated
        actions are those that are part of a larger
        action and depend on the larger action for
        their justification. Interdependent actions are
        those that have no independent utility apart
        from the action under consideration.

Id. § 402.02 (emphasis added). The parties categorize the
effects of the PPF easement as indirect effects, which
explicitly incorporate the reasonably certain standard. 3
    The government contends, however, that the actual
effects of the mitigation measures need not be reasonably
certain. So long as the mitigation measures are reasonably
certain to occur, the Service’s assessment of the effects of
those measures need only a rational basis in record evidence.
Under the government’s proposed standard, the Service
must be reasonably certain that it will acquire the PPF

3
  We take no position as to whether the “reasonably certain” standard in
50 C.F.R. §§ 402.14 and 402.02 differs from or exceeds the statutory
“likely” standard of 16 U.S.C. § 1536(a)(2). Neither party briefed this
issue, and in any event the outcome in this case will be the same,
regardless of the standard.
14          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

easement and that it will have the ability, on paper, to limit
agricultural irrigation. Cf. Bernhardt, 982 F.3d at 747
(“Mitigation measures relied upon in a [BiOp] must
constitute ‘a clear, definite commitment of resources,’ and
be ‘under agency control or otherwise reasonably certain to
occur.’” (quoting Nat’l Wildlife Fed. v. Nat’l Marine
Fisheries Serv., 524 F.3d 917, 936 & n.17 (9th Cir. 2008))).
Thus, according to the government, the Service’s assessment
of the easement’s estimated water savings must only be
rational.
    The government’s proffered standard conflicts with the
language of the regulation. Under the government’s
interpretation, the regulation says only that the Service must
be reasonably certain that the agency will engage in
proposed mitigation measures. But the regulation requires
that the “effects” of the “proposed action” be reasonably
certain—not the action itself. 50 C.F.R. § 402.02. 4 True,

4
  Since the BiOp was issued here, 50 C.F.R. § 402.02 and its definition
for “effects of the action” have been revised. This new language was not
meant to change how the regulation operates but clarifies and simplifies
the regulation. See Endangered and Threatened Wildlife and Plants;
Regulations for Interagency Cooperation, 84 Fed. Reg. 44,976, 44,976–
77 (Aug. 27, 2019) (codified at 50 C.F.R. § 402). To that end, the
regulation now defines “effects of an action” as:

         all consequences to listed species or critical habitat
         that are caused by the proposed action, including the
         consequences of other activities that are caused by the
         proposed action. A consequence is caused by the
         proposed action if it would not occur but for the
         proposed action and it is reasonably certain to occur.

50 C.F.R. § 402.02 (2019) (emphasis added). This clarification makes it
even clearer that “reasonably certain” language applies to the benefits of
an action and not the action itself. 50 C.F.R. § 402.02 (2019).
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND         15

whether the mitigation measures are “reasonably certain to
occur” is relevant in determining whether the effects of those
measures are reasonably certain to occur. See Bernhardt,
982 F.3d at 743, 747; Nat’l Wildlife Fed’n v. Nat’l Marine
Fisheries Serv. (NWF), 524 F.3d 917, 935–36 (9th Cir.
2008). But that is true for the simple reason that if a
mitigation measure is not reasonably certain to occur, it is
not reasonably certain to lead to tangible benefits. The
converse, however, does not follow—just because a
mitigation measure is reasonably certain to occur does not
mean that it is reasonably certain to yield tangible benefits.
So neither text nor logic supports the government’s
contention that only the mitigation measures must be
reasonably certain. In short, we must assess whether the
effects of the mitigation measures—here, water savings—
were reasonably certain to occur.
    We, however, still must determine what it means for an
effect to be “reasonably certain.” We hold that an effect is
reasonably certain to occur if its occurrence is based on
“clear and substantial information,” 50 C.F.R. § 402.17(b)
(2019), not “speculation or conjecture,” 84 Fed. Reg. at
44,977. Although the effect need not be “guaranteed to
occur,” there must be a “degree of certitude” it will happen.
84 Fed. Reg. at 44,977. This is not a particularly stringent
standard to meet, but the government must do more than rely
on speculation sprinkled with dabs of evidence. So, unlike
what CBD implies, this does not mean that the Service could
credit the PPF easement for water savings only if the
easement were to interrupt a specific, identified deal to use
the land for agricultural purposes. Rather, there must be
“solid information” that agricultural use would have
occurred in the counterfactual world in which the easement
did not exist. Id.
16        CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

     That reasonable certainty is missing here. To start, the
BiOp struggles to provide evidence that the land covered by
the easement would have ever been used for agriculture. The
government wants us to believe that the land at issue would
have been used for agriculture because of its historical use.
By the time the BiOp was assessing the water savings of the
easement, however, that history was stale—the land had not
been used for agricultural purposes for almost a decade, and
some (though not all) of the irrigation infrastructure had
been removed from the land. And even though it was legally
feasible for irrigation to resume, the extended dormant
period renders speculative the BiOp’s conclusion that the
land would resume agricultural use. The reasonably certain
standard is not met when speculation and not “solid
information” undergirds the agency action’s claimed effects.
See id. at 44,993. Thus, the groundwater demand accounting
is flawed as it relies on water savings from the PPF easement
that were not reasonably certain to occur.
    The BiOp also assumed that water savings would begin
immediately in 2014. But the Service failed to show that it
was reasonably certain that agricultural pumping would have
otherwise occurred as soon as the calendar flipped over into
2014. Indeed, the BiOp acknowledged that the Service was
unsure “when agricultural pumping would recommence
without the conservation easement.” This uncertainty kept
the Service from including the effects of the PPF easement
in the groundwater model. Yet, without citing any more
evidence, the Service depended on the PPF easement in the
groundwater demand accounting to establish a groundwater
surplus beginning in 2014. Cf. State Farm, 463 U.S. at 43
(“Normally, an agency rule would be arbitrary and
capricious if the agency . . . offered an explanation for its
decision that runs counter to the evidence before the
            CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND                 17

agency.”). The Service’s reliance on the uncertain timing of
the PPF easement’s water savings further undermines the
groundwater demand accounting.
    In sum, the Service was not reasonably certain about
whether and when the PPF easement would produce water
savings. 5 The groundwater demand accounting was thus
flawed, rendering the jeopardy and adverse-modifications
determinations for the protected species arbitrary and
capricious. See Bernhardt, 982 F.3d at 748.
II. CBD’s Challenge to the BiOp’s                          Jeopardy
    Determination    for the Northern                       Mexican
    Gartersnake Fails.
    Beyond its challenge of the PPF easement, CBD argues
that the BiOp’s jeopardy determination for the northern
Mexican gartersnake was arbitrary and capricious because:
(1) the BiOp irrationally concluded that the gartersnake
would migrate when faced with decreased baseflows in the
Babocomari River, (2) the BiOp overlooked the Service’s
past statements about the species-wide consequences for
losing low-density gartersnake populations, and (3) the
BiOp impermissibly minimized the Fort’s expected effects
on the gartersnake by comparing any losses against the
baseline of an already-depleted population.        These
arguments fail.

5
  CBD also argues that the BiOp miscalculated how much water the PPF
easement would have saved, assuming that the land would have been
used for agriculture but for the easement. We need not decide whether
the BiOp’s calculation was erroneous because we hold that, on the record
below, it was not reasonably certain whether and when the PPF easement
would provide water savings.
18        CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

     A. The BiOp did not err in relying on the
        gartersnake’s ability to migrate.
    The BiOp concluded that the depleted baseflow in the
Babocomari River will minimally affect the gartersnake
population partly because the gartersnakes can move up- or
downstream into more suitable habitats. CBD maintains that
this conclusion lacks scientific support and contradicts the
Service’s previous findings on the gartersnake’s migration
habits. Neither of CBD’s contentions is correct.
    The BiOp concluded that gartersnakes would migrate
when confronted with depleted baseflow in the Babocomari
River because they are considered “opportunistic foragers,
meaning they will move on the landscape to areas that
present the best foraging potential.” According to the
proposed rule, migration is an important part of the
gartersnake’s habitat distribution. 78 Fed. Reg. at 41,508.
This provides a sufficient scientific explanation for the
Service’s conclusion. See State Farm, 463 U.S. at 43 (“We
will, however, ‘uphold a decision of less than ideal clarity if
the agency’s path may reasonably be discerned.’” (quoting
Bowman Transp., Inc. v. Ark.-Best Freight Sys., Inc., 419
U.S. 281, 286 (1974))).
    But this is not enough for CBD. Instead, it argues that
the BiOp’s analysis incorporated scientific evidence that
contradicts its conclusion that the snakes could migrate if
faced with depleted baseflows. CBD points out that the
proposed rule cited one study finding gartersnakes
“‘wandering’ only ‘hundreds of meters’ from water” and
another finding them 600 feet from water. App. Br. at 59
(quoting Endangered and Threatened Wildlife and Plants;
Designation of Critical Habitat for the Northern Mexican
Gartersnake and Narrow-Headed Gartersnake, 78 Fed. Reg.
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND        19

41,550, 41,554, 41,557 (July 7, 2013) (codified at 50 C.F.R.
§ 17)). CBD points out that these distances are far shorter
than the ten kilometers that the snakes might have to migrate
if the Babocomari River’s baseflow is depleted. The BiOp,
however, acknowledged this evidence, explaining that the
cited distances represented the lateral distance from
permanent water that the gartersnake will travel, not the
maximum distance along a body of water that a gartersnake
could move. See id. at 41,557.
    Not to be discouraged, CBD maintains that the lateral
distance is the better measurement when considering the
garternsnake’s ability to migrate if faced with the
Babocomari River’s depleted baseflow. But the decision of
what is the best measurement to support a conclusion is
typically left up to the Service. See San Luis & Delta-
Mendota Water Auth. v. Locke, 776 F.3d 971, 997 (9th Cir.
2014) (citing San Luis & Delta-Mendota Water Auth. v.
Jewell, 747 F.3d 581, 610 (9th Cir. 2014)). Thus, the record
supports that the Service considered the relevant factors and
articulated a rational connection. For our purposes, that is
enough to maintain its jeopardy determination. State Farm,
463 U.S. at 43.
   B. The BiOp did not err in concluding that the
      effects on the gartersnakes near the Babocomari
      River would have minimal species-wide effects.
    CBD also argues that the Service failed to address its
own findings when it concluded that the negative effects on
the low-population habitat near the Babocomari River would
not jeopardize the species as a whole. The Service must
assess whether the agency action “reasonably would be
expected, directly or indirectly, to reduce appreciably the
likelihood of both the survival and recovery” of the species.
20        CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

50 C.F.R. § 402.02.        When making this jeopardy
determination, the Service is generally concerned with the
proposed action’s impact on the whole species. See Wild
Fish Conservancy v. Salazar, 628 F.3d 513, 529 (9th Cir.
2010). But where the agency has identified that protecting
individual populations is important to protecting the entire
species, the agency should elaborate on why the loss of an
individual population would not tip the species into
jeopardy. See id. Here, the Service noted that any loss of
this population of gartersnakes was concerning because it
would reduce the species’ genetic resiliency. 78 Fed. Reg.
at 41,536. According to CBD, by disregarding this
connection between losing a few gartersnakes and species-
wide jeopardy, the BiOp’s determination overlooked an
important fact.
    But the BiOp’s conclusion was not arbitrary and
capricious. To begin, the BiOp explicitly incorporated the
proposed rule on which CBD relies, establishing that the
Service considered the species-wide effect that would be
caused by any loss of gartersnakes. Cf. Wild Fish, 628 F.3d
at 529–30. There is also a rational connection between the
facts and the jeopardy determination. The Service stressed
that it expected the Fort to have minimal effect on the
gartersnakes near the Babocomari River—indeed, it
expected it to help some—and the estimate of lost
gartersnakes was small compared to the total population.
Given the BiOp’s findings about the minimal effect on
gartersnakes, it was rational for the Service to conclude that
the Fort would not “reduce appreciably the likelihood of
both the survival and recovery” of the gartersnake, even
assuming each lost gartersnake creates an external threat on
the total population. 50 C.F.R. § 402.02 (emphasis added);
see also Turtle Island Restoration Network v. U.S. Dep’t of
           CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND          21

Com., 878 F.3d 725, 750–51 (9th Cir. 2017) (Callahan, J.,
dissenting in part).
   C. The BiOp did not err in concluding that the Fort
      would only minimally impact the gartersnake
      population because the population near the
      Babocomari River was already depleted.
    Finally, CBD maintains that the BiOp rested on a legal
error. Under 50 C.F.R. § 402.14(g)(4), the Service must
“[a]dd the effects of the action . . . to the environmental
baseline and in light of the status of the species.” This court
has interpreted this language to mean that the jeopardy
determination must assess whether, given the ongoing threat
to the species, the proposed action will tip the species into
deeper jeopardy. NWF, 524 F.3d at 930 (“[E]ven where
baseline conditions already jeopardize a species, an agency
may not take action that deepens the jeopardy by causing
additional harm.”). The jeopardy determination cannot,
however, rest on the conclusion that the agency action only
minimally contributes to the species’ ongoing jeopardy. Id.
That is, an agency action can still cause jeopardy even if it is
only one small part of the overall threat to the species. But
the Service may conclude that the agency will not contribute
to the species’ jeopardy based on its minimal impact on an
already-depleted subpopulation. Cf. id. (“Agency action can
only ‘jeopardize’ a species’ existence if that agency action
causes some deterioration in the species’ pre-action
condition.”). Stated simply, if there are no longer any snakes
there, then the Service can reasonably conclude that the
proposed action will not affect any snakes.
    The BiOp did just that. The BiOp did not say that the
Fort’s effect is small when compared to other ongoing
threats to the gartersnake population. Instead, it recognized
22        CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

that, at the baseline, there are few (if any) gartersnakes near
the Babocomari River.           Because the population of
gartersnakes in that area is already low, any decreased
baseflows would not affect enough gartersnakes to tip the
species into jeopardy. See id. That is a rational and
appropriate conclusion that does not warrant a remand.
                      CONCLUSION
    We VACATE the 2014 BiOp, REVERSE the district
court’s decision to grant the government’s motion for
summary judgment on the PPF easement, and REMAND
with instructions for the Army and the Service to reevaluate
its water-savings analysis in a new biological opinion
consistent with this opinion.

COLLINS, Circuit Judge, concurring in part and
concurring in the judgment:

    I concur in the majority’s judgment to the extent that it
partially reverses and remands this case to the district court
with instructions to remand the matter back to the relevant
agencies for the preparation of a new “Biological Opinion”
that rests on a revised water-savings analysis. However, I
reach that conclusion on somewhat narrower grounds than
the majority.
    The Endangered Species Act (“ESA”) requires each
federal agency, in consultation with the appropriate
Secretary or his or her delegee, to “insure that any action
authorized, funded, or carried out by such agency . . . is not
likely to jeopardize the continued existence of any
endangered species or threatened species or result in the
destruction or adverse modification of habitat of such
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND         23

species” that has been determined to be “critical.” 16 U.S.C.
§ 1536(a)(2) (emphasis added). As the majority notes, the
relevant regulations implementing this directive and related
ESA provisions require the identification and assessment of
both direct and indirect effects of agency action. See, e.g.,
50 C.F.R. §§ 402.02, 402.14(g)(3), (h)(1)(iii). At the time
that the Biological Opinion in this case was issued, those
regulations defined “indirect effects” as “those that are
caused by the proposed action and are later in time, but still
are reasonably certain to occur.” 50 C.F.R. § 402.02 (2013).
In their briefs in this court, Plaintiffs and the Government
vigorously contest whether this “reasonably certain to
occur” standard for identifying future effects is more
demanding than the statutory “likely” standard for assessing
effects. I agree with the majority that we need not resolve
this issue. See Opin. at 13 n.3. Even assuming that the
Government only had to show that the groundwater demand
accounting’s projected water savings from the Preserve
Petrified Forest (“PPF”) easement were “likely,” the
Biological Opinion fails to adequately make that showing.
    In explaining why the benefits from the PPF easement
were excluded from the groundwater flow model, the
Biological Opinion states that there was “uncertainty in
when agricultural pumping would recommence without the
conservation easement.”      Despite acknowledging that
uncertainty, the Biological Opinion’s groundwater demand
accounting     nonetheless    simply     assumes—without
appropriate explanation—that actual agricultural use was
prevented by the easement nearly from the moment the
easement took effect. Moreover, the record reflects that the
prior agricultural use of the relevant property stopped in
2005, and the Biological Opinion does not explain why it
thought that such use would likely recommence absent the
24        CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND

easement. Indeed, the groundwater modeling report merely
states that, “[w]ithout the Fort’s purchase of the easement,
the pumping could recommence.” The Government now has
an explanation for why it is reasonable to conclude that
agricultural use would likely have resumed after so many
years—namely, that after 2005, the property was caught up
in the alleged land speculation scheme at issue in United
States v. Renzi, 769 F.3d 731 (9th Cir. 2014)—and Plaintiffs
have counterarguments on that score. However, it does not
appear that this explanation was ever actually considered by
the agency. Rather, the agency appears to have assumed,
without adequate explanation, that there would be immediate
water savings to a degree that the Biological Opinion itself
elsewhere recognized to be uncertain. “The Biological
Opinion was therefore arbitrary and capricious in failing to
examine the relevant data and articulate a satisfactory
explanation for its action including a rational connection
between the facts found and the choice made.” Center for
Bio. Diversity v. U.S. Bureau of Land Mgmt., 698 F.3d 1101,
1124 (9th Cir. 2012) (citations and internal quotation marks
omitted).     And because, as the majority notes, the
Government conceded at oral argument that the groundwater
demand accounting was an integral component of the
Biological Opinion’s relevant challenged determinations
under the ESA, see Opin. at 12, I agree with the majority’s
conclusion that the matter must be remanded to the pertinent
agencies so that a new Biological Opinion can be prepared
that relies on an appropriate re-evaluation of any expected
water savings from the PPF easement.
    In reaching the same ultimate conclusion, however, the
majority unnecessarily relies on the contention that the
“reasonably certain” standard requires a quantum and
quality of proof that apparently exceeds what is normally
          CTR. FOR BIOLOGICAL DIVERSITY V. HAALAND          25

required under traditional standards of administrative
review. Thus, it is not enough that the agency’s findings
have a “rational basis in record evidence,” the majority
concludes; rather, the agency must adduce “solid” and “clear
and substantial information” that demonstrates a “degree of
certitude” about the predicted savings. See Opin. at 13, 15.
These requirements are partly drawn from a regulation
adopted several years after the Biological Opinion in this
case was issued, see 50 C.F.R. § 402.17(b) (2019), and to the
extent that they merely reflect the statutory requirement that
“each agency shall use the best scientific and commercial
data available” in evaluating the likely effects of an agency
action on relevant species, see 16 U.S.C. § 1536(a)(2), they
are unobjectionable. But to the extent that the majority’s
standards purport to supplant traditional administrative law
standards or to adopt an underlying substantive standard that
differs from the statutory “likely” standard, I would refrain
from any such unnecessary and doubtful holding in this case.
    I concur, however, in Part II of the court’s opinion,
which rejects Plaintiffs’ further contentions that are specific
to the Government’s challenged determinations as to the
northern Mexican gartersnake.
    For the foregoing reasons, I concur in part and concur in
the judgment in part.