                FOR PUBLICATION

  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT


ALASKA OIL AND GAS                   No. 14-35806
ASSOCIATION; AMERICAN
PETROLEUM INSTITUTE; STATE              D.C. No.
OF ALASKA; NORTH SLOPE             4:13-cv-00018-RRB
BOROUGH; INUPIAT COMMUNITY
OF THE ARCTIC SLOPE;
NORTHWEST ARCTIC BOROUGH;
ARCTIC SLOPE REGIONAL
CORPORATION; NANA
REGIONAL CORPORATION, INC.,
           Plaintiffs-Appellees,

               v.

PENNY PRITZKER, U.S. Secretary
of Commerce; NATIONAL
MARINE FISHERIES SERVICE;
NATIONAL OCEANIC AND
ATMOSPHERIC ADMINISTRATION;
KATHRYN D. SULLIVAN, in her
official capacity as the Acting
Under Secretary of Commerce
for Oceans and Atmosphere and
the Acting Administrator,
National Oceanic and
Atmospheric Administration;
SAMUEL D. RAUCH, III, in his
official capacity as the Acting
Assistant Administrator for
2        ALASKA OIL & GAS ASS’N V. PRITZKER

Fisheries, National Oceanic and
Atmospheric Administration,
           Defendants-Appellants.



ALASKA OIL AND GAS                    No. 14-35811
ASSOCIATION; AMERICAN
PETROLEUM INSTITUTE; STATE               D.C. No.
OF ALASKA; NORTH SLOPE              4:13-cv-00018-RRB
BOROUGH; INUPIAT COMMUNITY
OF THE ARCTIC SLOPE;
NORTHWEST ARCTIC BOROUGH;               OPINION
ARCTIC SLOPE REGIONAL
CORPORATION; NANA
REGIONAL CORPORATION, INC.,
           Plaintiffs-Appellees,

               v.

PENNY PRITZKER, U.S. Secretary
of Commerce; NATIONAL
MARINE FISHERIES SERVICE;
NATIONAL OCEANIC AND
ATMOSPHERIC ADMINISTRATION;
KATHRYN D. SULLIVAN, in her
official capacity as the Acting
Under Secretary of Commerce
for Oceans and Atmosphere and
the Acting Administrator,
National Oceanic and
Atmospheric Administration;
SAMUEL D. RAUCH, III, in his
official capacity as the Acting
        ALASKA OIL & GAS ASS’N V. PRITZKER            3

Assistant Administrator for
Fisheries, National Oceanic and
Atmospheric Administration,
                     Defendants,

              and

CENTER FOR BIOLOGICAL
DIVERSITY,
Intervenor-Defendant-Appellant.


      Appeal from the United States District Court
               for the District of Alaska
      Ralph R. Beistline, District Judge, Presiding

         Argued and Submitted August 4, 2016
                 Anchorage, Alaska

                Filed October 24, 2016

      Before: Raymond C. Fisher, Richard A. Paez
        and Andrew D. Hurwitz, Circuit Judges.

                Opinion by Judge Paez
4           ALASKA OIL & GAS ASS’N V. PRITZKER

                            SUMMARY*


                       Environmental Law

    The panel reversed the district court’s summary judgment
in favor of plaintiffs in their action challenging federal
officials’ listing decision under the Endangered Species Act,
concerning certain “sea ice seal” species; and held that the
National Marine Fisheries Service’s (“NMFS”) listing
decision was reasonable.

    The NMFS concluded that the Okhotsk and Beringia
distinct population segments of the Pacific bearded seal
subspecies were likely to become endangered within the
foreseeable future. NMFS used climate projections to
determine that the loss of sea ice over shallow waters in the
Arctic would leave the Pacific bearded seal subspecies
endangered by the year 2095. Plaintiffs filed lawsuits
challenging the listing decision under the ESA’s citizen suit
provision and the Administrative Procedure Act.

    The panel held that in light of the NMFS’s robust
rulemaking process, and pursuant to a highly deferential
standard of review, the NMFS’s final rule listing the Beringia
distinct population segment as threatened was not arbitrary or
capricious, and its listing was supported by substantial
evidence. Specifically, the panel held that the NMFS did not
act arbitrarily or capriciously in concluding that the effects of
global climate change on sea ice would endanger the Beringia
distinct population segment in the foreseeable future. The

    *
      This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
          ALASKA OIL & GAS ASS’N V. PRITZKER                5

panel further held that the administrative record demonstrated
that NMFS provided a reasonable and evidence-based
justification for its mid-century and end-of-century sea ice
projections.

    The panel held that NMFS clearly fulfilled its procedural
and substantive obligations under Section 4(i) of the
Endangered Species Act, 16 U.S.C. § 1533(i), to provide the
State of Alaska with a written justification.


                        COUNSEL

Robert Parke Stockman (argued), Meredith L. Flax, Mary E.
Hollingsworth, and Katherine W. Hazard, Attorneys; John C.
Cruzen, Assistant Attorney General; Environment & Natural
Resources Division, United States Department of Justice,
Washington, D.C.; Demian Schane, Office of the General
Counsel, United States Department of Commerce, Juneau,
Alaska; for Defendants-Appellants.

Kristen Monsell (argued), Emily Jeffers, and Miyoko
Sakashita, Oakland, California; Rebecca Noblin, Anchorage,
Alaska; as and for Intervenor-Defendant-Appellant.

Jeffrey W. Leppo (argued) and Ryan P. Steen, Stoel Rives
LLP, Seattle, Washington, for Plaintiffs-Appellees Alaska Oil
and Gas Association, and American Petroleum Institute.

Bradley E. Meyen, Senior Assistant Attorney General, Alaska
Department of Law, Anchorage, Alaska; Murray D. Feldman,
Holland & Hart LLP, Boise, Idaho; Christina F. Gomez,
Holland & Hart LLP, Denver, Colorado; for Plaintiff-
Appellee State of Alaska.
6         ALASKA OIL & GAS ASS’N V. PRITZKER

Tyson C. Kade (argued), Van Ness Feldman LLP,
Washington, D.C.; Matthew A. Love, Van Ness Feldman
LLP, Seattle, Washington; for Plaintiffs-Appellees North
Slope Borough, Inupiat Community of the Arctic Slope,
Northwest Arctic Borough, Arctic Slope Regional
Corporation, and NANA Regional Corporation, Inc.


                         OPINION

PAEZ, Circuit Judge:

    The National Marine Fisheries Service (“NMFS”) used
climate projections to determine that the loss of sea ice over
shallow waters in the Arctic would leave the Pacific bearded
seal subspecies (Erignathus barbatus nauticus) endangered
by the year 2095. This case turns on one issue: When NMFS
determines that a species that is not presently endangered will
lose its habitat due to climate change by the end of the
century, may NMFS list that species as threatened under the
Endangered Species Act? The district court answered in the
negative, ruling that NMFS’s listing decision was arbitrary
and capricious. We hold that on the basis of the
administrative record, NMFS’s listing decision is reasonable.
Accordingly, we reverse the district court’s grant of summary
judgment in favor of Plaintiffs.

                              I.

    In 2008, the Center for Biological Diversity (“CBD”)
filed a petition requesting that the Secretary of Commerce list
three “sea ice seal” species as endangered or threatened under
the Endangered Species Act (“ESA” or “the Act”), 16 U.S.C.
§§ 1531–44. See 16 U.S.C. § 1533(b)(1)(3) (citing 5 U.S.C.
           ALASKA OIL & GAS ASS’N V. PRITZKER                      7

§ 553(e)) (relating to the process for consideration of a
petition for rulemaking); Final Listing Rule: Threatened
Status for the Beringia & Okhotsk Distinct Population
Segments of the Erignathus barbatus nauticus Subspecies of
the Bearded Seal, 77 Fed. Reg. 76,740 (Dec. 28, 2012)
(“Listing Rule”). After a lengthy administrative process that
included two rounds of peer review, several rounds of public
notice and comment, and public hearings, NMFS concluded
that the Okhotsk and Beringia distinct population segments
(“DPS”) of the Pacific bearded seal subspecies (Erignathus
barbatus nauticus) were “likely to become . . . endangered
species within the foreseeable future throughout . . . a
significant portion of [their] range.” 16 U.S.C. § 1532(20);
Listing Rule, 77 Fed. Reg. at 76,740.

    Plaintiffs Alaska Oil and Gas Association (“AOGA”), the
State of Alaska, and North Slope Borough (collectively,
“Plaintiffs”) filed separate lawsuits challenging the listing
decision under the ESA’s citizen suit provision, 16 U.S.C.
§ 1540(g), and the Administrative Procedure Act (“APA”),
5 U.S.C. § 706.1 Plaintiffs alleged, inter alia, that the listing
decision was not based on the “best scientific and commercial
data available” in violation of 16 U.S.C. § 1533(b)(1)(A); the
population of bearded seals was plentiful; a lack of reliable
population data made it impossible to determine an extinction
threshold; NMFS’s use of predictive climate projections
beyond 2050 were speculative; NMFS had unreasonably


    1
      The American Petroleum Institute was added as a plaintiff in
AOGA’s amended complaint; the Inupiat Community of the Arctic Slope,
Northwest Arctic Borough, Arctic Slope Regional Corporation, and
NANA Regional Corporation were added as plaintiffs in the North Slope
Borough’s amended complaint. The district court consolidated all the
cases and granted CBD leave to intervene as a defendant.
8         ALASKA OIL & GAS ASS’N V. PRITZKER

“changed tack” from its previous Arctic sea-ice listing
decisions; and NMFS had failed to demonstrate a causal
connection between the loss of sea ice and the impact of that
loss to the Okhotsk and Beringia DPS’s viability. In addition,
the State of Alaska alleged that NMFS failed to adequately
respond to its public comments and failed to comply with the
ESA’s state cooperation provisions. See id. § 1533(i);
50 C.F.R. § 424.18(c).

    The district court denied relief with respect to the
Okhotsk DPS for lack of Article III standing. Alaska Oil &
Gas Ass’n v. Pritzker, No. 4:13-cv-18-RRB, 2014 WL
3726121, at *3–4 (D. Alaska July 25, 2014) (“Pritzker”). The
district court, however, granted summary judgment to
Plaintiffs on their challenge to NMFS’s decision to list the
Beringia DPS as a threatened species. The court concluded
that NMFS’s decision was arbitrary and capricious because
NMFS’s long-term climate projections were volatile and the
agency lacked data on the bearded seal’s adaptability and
population trends, including “a specified time” at which the
seal would reach an extinction threshold. Id. The district
court also concluded that the ESA required NMFS to provide
Alaska with a separate written justification for rejecting the
State’s comments and granted summary judgment to Alaska
on that claim. Id. at *10 (citing Alaska Oil & Gas Ass’n v.
Salazar, 916 F. Supp. 2d 974, 1003 (D. Alaska 2013), rev’d
sub nom., Alaska Oil & Gas Ass’n v. Jewell, 815 F.3d 544
(9th Cir. 2016) (“Jewell”)). The district court vacated the
Listing Rule, explaining that NMFS’s attempt to predict the
bearded seal’s viability beyond 50 years was “too speculative
and remote to support a determination that the bearded seal is
in danger of becoming extinct.” Id. at *15.
            ALASKA OIL & GAS ASS’N V. PRITZKER                          9

    NMFS and CBD timely appealed. As we explain below,
NMFS’s decision to list the Beringia DPS as threatened was
not arbitrary, capricious, or otherwise in contravention of
applicable law. Accordingly, we reverse the district court’s
grant of summary judgment in favor of Plaintiffs.

                                   II.

    We review de novo the district court’s grant of summary
judgment to determine whether NMFS’s ESA listing decision
was “arbitrary, capricious, an abuse of discretion, or
otherwise not in accordance with law.” 5 U.S.C. § 706(2);
Jewell, 815 F.3d at 554. Our review is “deferential and
narrow,” requiring a “high threshold for setting aside agency
action” following public notice and comment. Id. (internal
quotation marks omitted). We presume an agency’s action is
valid, and we will affirm that action “so long as the agency
‘considered the relevant factors and articulated a rational
connection between the facts found and the choices made.’”
Id. (quoting Nw. Ecosys. All. v. U.S. Fish & Wildlife Serv.,
475 F.3d 1136, 1140 (9th Cir. 2007)).

                                  III.

    In October 2009, NMFS established a Biological Review
Team of eight marine mammal biologists, a fishery biologist,
a marine chemist, and a climate scientist to review the status
of the “best scientific and commercial data available”
regarding bearded seals.2 Listing Rule, 77 Fed. Reg. at
76,740.    NMFS solicited four scientists to conduct


    2
      The district court upheld the agency’s rule listing the Okhotsk DPS,
a ruling not contested on appeal. Pritzker, 2014 WL 3726121, at *3–4.
Accordingly, we limit our review to the Beringia DPS listing.
10          ALASKA OIL & GAS ASS’N V. PRITZKER

independent peer reviews of the Review Team’s report. Id.
at 76,740 & 76,750. Based on the Review Team’s
assessment and the peer reviewers’ comments, NMFS
published a proposed rule listing the Beringia and Okhotsk
bearded seal DPSs as threatened under the ESA. Id.; see also
Proposed Rule, 75 Fed. Reg. 77,496 (Dec. 10, 2010).

    The status and peer review reports found that the bearded
seal (Erignathus barbatus) lives throughout the Arctic and
Northern Atlantic Oceans, including in the Chukchi,
Beaufort, and Bering Seas; Sea of Okhotsk; Sea of Japan; and
waters of Arctic Canada (Hudson and Baffin Bays), Svalbard
(Norway), and Russia.          Because bearded seals are
widespread, have low population densities, and spend
significant time under water, it is difficult to obtain a reliable
estimate of their current population. Listing Rule, 77 Fed.
Reg. at 76,742. The bearded seal is commonly divided into
two subspecies3—E. b. barbatus, which primarily inhabits the
Atlantic, and E. b. nauticus, which inhabits the Pacific.
Noting that there were “regions of intergrading” between the
Atlantic and Pacific subspecies, NMFS identified two distinct
Pacific population segments. Proposed Rule, 75 Fed. Reg. at
77,499–501. One group lived exclusively in the Sea of
Okhotsk (the Okhotsk DPS), and the remaining seals were
found throughout the Bering and Chukchi Seas (the Beringia



     3
      The ESA defines a species as “any subspecies of . . . wildlife . . . ,
and any distinct population segment of any species of . . . wildlife which
interbreeds when mature.” 16 U.S.C. § 1532(16). The Act does not
define “distinct population segment.” NMFS’s policy, however, provides
guidance on the factors the agency must consider before determining if a
population is a distinct segment. See Nw. Ecosys. All., 475 F.3d at 1138,
1141–44 (discussing the distinct population segment policy and the level
of deference afforded to it).
          ALASKA OIL & GAS ASS’N V. PRITZKER                 11

DPS), with very little mixing between the two groups. Id. at
77,500.

    The review concluded that bearded seals generally prefer
to hunt organisms found on the ocean floor. As a result, the
seals prefer to congregate where non-contiguous sea ice floes
appear over shallow water between 50 to 200 meters deep,
and the seals avoid “unbroken, heavy, drifting ice or large
areas of multi-year ice” located over deeper waters. Id. at
77,498. The seals use ice floes to give birth (whelp) and to
nurse their pups; to allow mothers close access to food
sources while nursing; to enable their pups to gain experience
with diving, swimming, and hunting away from their
predators; to provide a location for males to attempt to attract
females; and to provide a platform where male seals can rest
while molting. Listing Rule, 77 Fed. Reg. at 76,742–44.
Year-round, bearded seals require access to shallow waters,
where the seals have access to “more productive” sea floors
with a higher availability of food.

    Using observational and predictive data from the
Intergovernmental Panel on Climate Change’s (“IPCC”)
Fourth Assessment Report, NMFS used six climate models to
determine when the Beringia DPS’s sea ice habitat would
degrade to such an extent that it would render the Beringia
DPS endangered, and it made available for public review its
methodology and data. Proposed Rule, 75 Fed. Reg. at
77,497. All independent peer reviewers agreed that the
Beringia DPS’s continued viability depended on the
availability of sea ice in the Bering and Barents Seas during
crucial life stages.

    After considering thousands of comments to the proposed
rule, NMFS extended the review period and sought additional
12         ALASKA OIL & GAS ASS’N V. PRITZKER

independent peer reviews of the sections of the status review
report that generated the greatest disagreement among peer
reviewers—the timing and magnitude of climate change
effects on the availability of sea ice in the Bering Sea.
Listing Rule, 77 Fed. Reg. at 76,741, 76,750–51. NMFS
additionally updated its climate predictions to include studies
published after the Proposed Listing Rule. Id. at 76,741 &
76,751. NMFS also held public hearings in Anchorage,
Barrow, and Nome to solicit comments. Id. at 76,750.

    NMFS determined that lack of access to non-continuous
sea ice in shallow waters would require bearded seals to make
significant adaptations to survive. Id. at 76,744. It reasoned
that lack of access to sea ice over shallow waters likely would
encourage seals in the Beringia DPS to whelp and nurse on
shore, increasing their risk of exposure to their primary
predators—polar bears and walruses. Id. at 76,742. Because
lack of sea ice in shallow water would require seals to forage
in deeper waters that lacked the ocean floor “productivity” of
shallow waters, NMFS concluded that as seals moved to
deeper waters, they faced a greater risk of being unable to
meet their subsistence needs. Id. And although bearded seals
did not require year-round access to sea ice floes in shallow
waters, most observational studies and peer reviewers opined
that lack of access to sea ice during periods of significant life
functions (birthing, nursing, hunting/foraging, molting) would
likely have a negative effect on the Beringia DPS. Id.

    Having concluded that the availability of sea ice in
shallow water was crucial to the Beringia DPS’s viability,
NMFS evaluated several climate models to determine the
magnitude and timing of climate change’s impact on the
availability of sea ice in areas inhabited by the Beringia DPS.
Id. at 76,744. Those projections indicated that by 2095, sea
          ALASKA OIL & GAS ASS’N V. PRITZKER                 13

ice in several regions where the Beringia DPS whelps will
have disappeared entirely during the mating, nursing, and
birthing season (April through June). Id. NMFS also
concluded that any periodic “gains” in sea ice as a result of
climate change were not really gains for the Beringia DPS.
Instead, independent peer reviewers cautioned that “gains” in
sea ice were illusory—seals would simply be able to access
areas they already used in earlier months, but not during the
times when critical life activities occurred. Id. The majority
of peer reviewers commented that increased sea ice formation
over deep waters would not offset sea ice losses in shallow
waters in the Bering, Chukchi, and Beaufort Seas. NMFS and
its peer reviewers also noted that although climate change had
caused sea ice patterns to shift during the year, there would be
a net decrease in the total number of days in which sea ice
would be available to the seals. Id. at 76,743–44.

    NMFS published its final rule designating the bearded
seal Beringia DPS as threatened in December 2012. Id. at
76,740. After providing 60 days’ pre-filing notice under ESA
Section 11, 16 U.S.C. § 1540(g)(2)(A)(i), AOGA filed suit
challenging NMFS’s listing decision.

                              IV.

   The Endangered Species Act seeks to recover endangered
and threatened species and to “reverse the trend towards
species extinction, whatever the cost.” Jewell, 815 F.3d at
550–51 (quoting Tenn. Valley Auth. v. Hill, 437 U.S. 153, 184
(1978)); 16 U.S.C. § 1531(b). To achieve that purpose, the
ESA requires the Secretary of Commerce, or her designee, to
14          ALASKA OIL & GAS ASS’N V. PRITZKER

identify and list endangered4 or threatened5 species. See
16 U.S.C. § 1533(a)(1) & (2); see also Nw. Ecosys. All.,
475 F.3d at 1137. When determining whether to list a
species, the reviewing agency must make its decision “solely
on the basis of the best scientific and commercial data
available.” 16 U.S.C. § 1533(b)(1)(A).

                                    A.

                                    1.

     Because CBD’s petition cited global warming as the
primary threat to bearded seals, NMFS focused its status
review on the impact of warmer temperatures on the Beringia
DPS. Proposed Rule, 75 Fed. Reg. at 77,503. To determine
the magnitude of climate change’s effect on sea ice, NMFS
utilized the IPCC’s predictive models, and it attempted to
apply those models to observational data that the Department
of the Interior collected annually regarding sea ice in the
Bering and Chukchi Seas. Id. at 77,503–05; Listing Rule
77 Fed. Reg. at 76,743. The IPCC’s climate predictions
through 2050 were based on already-collected data about
present-day emissions.6 Its climate projections for 2050 to


     4
       The Act defines an “endangered species” as “any [non-insect]
species which is in danger of extinction throughout all or a significant
portion of its range.” 16 U.S.C. § 1532(6).
     5
      A “threatened species” is “any species which is likely to become an
endangered species within the foreseeable future throughout all or a
significant portion of its range.” 16 U.S.C. § 1532(20).
     6
      The Fish and Wildlife Service (“FWS”) previously used the IPCC’s
2050 climate projections to justify its decision to list the polar bear as a
threatened species. See Safari Club Int’l v. Salazar (In re Polar Bear ESA
            ALASKA OIL & GAS ASS’N V. PRITZKER                          15

2100, however, used contemporary data to predict potential
climate trends under multiple scenarios. Proposed Rule,
75 Fed. Reg. at 77,503. Those models showed greater
volatility, and thus less reliable predictive value, in the
Arctic. Id. Because modeling for the second half of the
century involved unknown variables (technological
improvement, changes in climate policy), the IPCC used
twenty-four models with slightly differing assumptions to
obtain simulations of the upper- and lower-bounds for the
increase in global temperatures from 2050 to 2100. Id.

    To account for uncertainty in the IPCC’s 2050 to 2100
predictions, NMFS used two models considered to be
particularly reliable with respect to Arctic sea ice, and it used
“medium” and “high” emissions scenarios to project monthly
sea ice concentrations between March and July for each
decade, beginning in 2025 and ending in 2095. Id. at
77,503–04. NMFS then compared the results of those
projections to its observational data regarding sea ice to
determine if the IPCC models performed reliably when
applied to the Arctic. Id. at 77,504. Six models performed
reliably in the Chukchi and east Siberian Seas, four
performed reliably in the Beaufort and east Bering Seas, and
one model performed reliably in the western Bering Sea. Id.
NMFS disclosed its methodology, as well as the limits of the
IPCC models, in the Proposed Listing Rule and in a Notice of
Availability of Special Independent Peer Review Reports.

    After confirming the models’ accuracy, NMFS applied
each to the areas occupied by the Beringia DPS to determine
the range of temperatures per month from 2050 to 2100, and


Listing & Section 4(d) Rule Litig.), 709 F.3d 1, 15–16 (D.C. Cir.2013) (“In
re Polar Bear Litig.”)
16        ALASKA OIL & GAS ASS’N V. PRITZKER

used those temperature projections to determine the impact of
local warming on sea ice melt. Id. NMFS’s projections
demonstrated that by May and June 2050, there would be no
sea ice in the Bering Strait, the East Siberian Shelf, or the
Barents or Bering Seas. Id. By July 2050, sea ice would
recede to less than 20% of the mean or disappear entirely
from the Beaufort, Chukchi, and East Siberian seas. Id. Most
dramatically, by the time NMFS sought a second round of
public comment on its climate projections, sea ice scientists
published research indicating that the IPCC climate models
understated the speed at which temperatures were rising at the
poles. Id. at 77,503. Using observational data, those studies
predicted that temperatures at the Arctic were 30 years ahead
of schedule and that there would be “[a] nearly sea ice free
summer Arctic by mid-century.” Id. at 77,504.

    Plaintiffs contend that NMFS used climate models that
cannot reliably predict the degree of global warming beyond
2050 or the effect of that warming on a subregion, such as the
Arctic. Although Plaintiffs frame their arguments as
challenging long-term climate projections, they seek to
undermine NMFS’s use of climate change projections as the
basis for ESA listings. Plaintiffs’ contention is unavailing; in
Alaska Oil and Gas Association v. Jewell, we adopted the
D.C. Circuit’s holding that the IPCC climate models
constituted the “best available science” and reasonably
supported the determination that a species reliant on sea ice
likely would become endangered in the foreseeable future.
815 F.3d at 558–59; In re Polar Bear Litig., 709 F.3d at 4–6,
9–11.

    We have stressed that we “must defer to the agency’s
interpretation of complex scientific data” so long as the
agency provides a reasonable explanation for adopting its
           ALASKA OIL & GAS ASS’N V. PRITZKER                  17

approach and discloses the limitations of that approach. Nw.
Ecosys. All., 475 F.3d at 1150; see also San Luis & Delta-
Mendota Water Auth. v. Jewell, 747 F.3d 581, 602 (9th Cir.
2014) (“The determination of what constitutes the best
scientific data available belongs to the agency’s special
expertise . . . . [and w]hen examining this kind of scientific
determination . . . a reviewing court must generally be at its
most deferential.” (internal quotation marks omitted)).
NMFS provided ample evidence of significant sea ice loss
from 2007 to 2050, a period in which specific data supports
the IPCC climate projections. Proposed Rule, 75 Fed. Reg.
at 77,503–05. Those projections indicate that during months
in which bearded seals used that ice for “critical life events”
such as mating, birthing, and nursing, most Beringia DPS
habitats will have lost most, if not all, of their sea ice. Id. at
77,504. By September 2010, observational data confirmed
that the amount of summer sea ice in the areas populated by
the Beringia DPS was 40% below the long-term average. Id.
at 77,503. NMFS has provided a reasonable explanation,
based on the best available scientific and commercial data,
for relying on those projections in its listing decision.

    NMFS’s projections for the second-half of the century are
also reasonable, scientifically sound, and supported by
evidence. There is no debate that temperatures will continue
to increase over the remainder of the century and that the
effects will be particularly acute in the Arctic. The current
scientific consensus is that Arctic sea ice will continue to
recede through 2100, and NMFS considered the best
available research to reach that conclusion. One independent
peer reviewer noted that nothing in “existing data would
change the general picture that sea ice habitats important to
bearded seals are disappearing and will continue to disappear,
especially in the Bering and Chukchi seas.” Excerpts of R. at
18        ALASKA OIL & GAS ASS’N V. PRITZKER

115, ECF No. 10. A second peer reviewer opined that it was
“more likely than not that the uncertainty attaching to 80-year
predictions of how changing climate will affect bearded seals
and their habitat has been, is being, and will be greatly
underestimated.” Excerpts of R. at 118, ECF No. 10. All
parties agree that there will be sea ice melt; the only
uncertainty is the magnitude of warming, the speed with
which warming will take place, and the severity of its effect.

     The fact that climate projections for 2050 through 2100
may be volatile does not deprive those projections of value in
the rulemaking process. The ESA does not require NMFS to
make listing decisions only if underlying research is ironclad
and absolute. See San Luis & Delta-Mendota Water Auth.,
747 F.3d at 602 (“[W]here the information is not readily
available, we cannot insist on perfection: [T]he best scientific
. . . data available, does not mean the best scientific data
possible.” (internal quotation marks omitted) (emphasis
added)). The ESA directs NMFS to make its determinations
“solely on the basis of the best scientific and commercial data
available . . . after conducting a review of the status of the
species.” 16 U.S.C. § 1533(b)(1)(A). After conducting that
assessment, if NMFS finds it likely that a species will
“become an endangered species within the foreseeable future
throughout all or a significant portion of its range,” it must
list that species as threatened. 16 U.S.C. §§ 1532(20),
1533(b)(1)(B)(ii). NMFS provided a reasonable and
scientifically supported methodology for addressing volatility
in its long-term climate projections, and it represented fairly
the shortcomings of those projections—that is all the ESA
requires. See Jewell, 815 F.3d at 558 (“To the extent that
Plaintiffs demand greater scientific specificity than available
data could provide, [they] echo the district court’s error in
demanding too high a standard of scientific proof.”).
            ALASKA OIL & GAS ASS’N V. PRITZKER                       19

    The majority of independent peer reviewers agreed that
NMFS’s long-term climate projections were based on the
“best scientific and commercial data available,” that there
was scientific consensus regarding the “direction and effect”
of climate change, that there would be significant sea ice loss
in the Beringia DPS’s habitat, and that such a significant loss
of habitat would almost certainly have a negative effect on
the bearded seal’s survival. Moreover, under NMFS’s 2007
to 2050 climate projections, even if global warming plateaued
in the second-half of the century, devastating sea ice losses
would still result during months that are currently critical to
the bearded seal’s propagation.7 Proposed Rule, 75 Fed. Reg.
at 77,501–06.

    Further, climate studies released and noticed for public
comment after the publication of the Proposed Listing Rule
indicated that the Arctic was warming at a much faster rate
than anticipated by the IPCC mid-century projections. Those
studies, which are included in the administrative record,
advised that observational data regarding current temperature
increases indicated that Arctic sea ice may disappear as early
as 2040—approximately 50 years earlier than NMFS
predicted when it suggested the Beringia DPS would lose its
sea ice habitat by 2095. See Jewell, 815 F.3d at 558–60
(“FWS also noted [in In re Polar Bear Litigation] that the
observational record of current sea ice losses indicates that
losses seem to be about 30 years ahead of the modeled values,


    7
       In the proposed and final rules, NMFS provided information
regarding the negative impact of mid-century sea ice melt on the bearded
seal’s survival. Proposed Rule, 75 Fed. Reg. at 77,503–04 & 77,506;
Listing Rule, 77 Fed. Reg. at 76,742–44. The district court did not
address those projections, but instead focused on the longer-term
projections, which predict a total loss of sea ice.
20         ALASKA OIL & GAS ASS’N V. PRITZKER

which suggests a seasonally ice-free Arctic may come a lot
sooner than expected.”).          The administrative record
demonstrates that NMFS provided a reasonable and evidence-
based justification for its mid-century and end-of-century sea
ice projections.

    The ESA does not require NMFS to base its decision on
ironclad evidence when it determines that a species is likely
to become endangered in the foreseeable future; it simply
requires the agency to consider the best and most reliable
scientific and commercial data and to identify the limits of
that data when making a listing determination. In light of the
data available to it during the rulemaking process, NMFS
reasonably concluded that there would be continued sea ice
loss over shallow waters, resulting in habitat loss that would
almost certainly threaten the Beringia DPS’s survival. NMFS
has provided a rational and reasonable basis for evaluating
the bearded seal’s viability over 50 and 100 years, and it has
candidly disclosed the limitations of the available data and its
analysis. The ESA does not require more, and NMFS did not
act arbitrarily or capriciously in concluding that the effects of
global climate change on sea ice would endanger the Beringia
DPS in the foreseeable future.

                               2.

    Plaintiffs advance three principal arguments to challenge
NMFS’s listing decision. First, Plaintiffs contend that
NMFS’s use of longer-term climate projections diverges from
its previous practice of setting the year 2050 as the outer
boundary of its “foreseeable future” analysis. NMFS has
argued, and several federal courts have agreed, that the
agency may determine the timeframe for its “foreseeable
future” analysis based upon the best data available for a
             ALASKA OIL & GAS ASS’N V. PRITZKER              21

particular species and its habitat. In re Polar Bear Litig.,
709 F.3d at 10–11, 15–16 (allowing NMFS to determine the
timeline for “foreseeable future” threats of extinction based
on the specific species, habitat, and best available science at
the time of listing); see also W. Watersheds Project v. Ashe,
948 F. Supp. 2d 1166, 1180 (D. Idaho 2013) (“The [agency’s]
assessment of the ‘foreseeable future’ is typically based on
the timeframes over which the best available scientific data
allow [the agency] to reliably assess threats and the species’
response to those threats . . . .” (internal quotation marks
omitted)); Ctr. for Biological Diversity v. Lubchenco, 758 F.
Supp. 2d 945, 967 (N.D. Cal. 2010) (observing that “the
length of time that constitutes the ‘foreseeable future’ for
listing purposes may vary depending on the species and the
threats it faces”).

    We apply the same standard of review whether an agency
issues a new policy or changes a previous policy position. Cf.
FCC v. Fox Television Stations, Inc., 556 U.S. 502, 513–14
(2009). An internal guidance document that reflects an
agency’s “body of experience and informed judgment,” but
that is not promulgated through rulemaking, is typically
afforded Skidmore8 deference. Fed. Express Corp. v.
Holowecki, 552 U.S. 389, 399 (2008); Alaska Dep’t of Envtl.
Conservation v. EPA, 540 U.S. 461, 488 (2004); United
States v. Mead Corp., 533 U.S. 218, 230–32 (2001). An
agency must provide a reasoned explanation for adoption of
its new policy—including an acknowledgment that it is
changing its position and if appropriate, any new factual
findings that may inform that change—but it need not
demonstrate that the new policy is better than its prior policy.
Fox Television Stations, 556 U.S. at 515; see also Price v.

   8
       Skidmore v. Swift & Co., 323 U.S. 134, 140 (1944).
22        ALASKA OIL & GAS ASS’N V. PRITZKER

Stevedoring Servs. of Am., Inc., 697 F.3d 820, 829–30 (9th
Cir. 2012); Nat’l Ass’n of Home Builders v. EPA, 682 F.3d
1032, 1037–38 (D.C. Cir. 2012).

    In 2009, the Department of the Interior issued an internal
memorandum notifying the FWS that its interpretation of the
“foreseeable future” must be supported by reliable data
regarding “threats to the species, how the species is affected
by those threats, and how the relevant threats operate over
time.” Office of the Solicitor of the U.S. Dep’t of the
Interior, Memorandum on the Meaning of “Foreseeable
Future” in Section 3(20) of the Endangered Species Act, No.
M-37021 (Jan. 16, 2009); see also Listing Rule, 77 Fed. Reg.
at 76,753 (citing Notice of Reinitiation of Status Review for
Ribbon Seal, 76 Fed. Reg. 77,467, 77,468 (Dec. 13, 2011)
(reevaluating the ribbon seal petition in light of new
information regarding sea ice decline)). The Solicitor noted
that a threat-specific evaluation of the best data available
would result in different “foreseeable future” time frames for
different species and for different threats. Mem. No. M-
37021 at 8.

    NMFS acknowledged in its final Listing Rule that,
consistent with the Solicitor’s opinion and beginning with the
bearded seal petition, it changed its interpretation of
“foreseeable future” to a more dynamic, species-specific and
evidence-based definition. Proposed Rule, 75 Fed. Reg. at
77,497; Listing Rule, 77 Fed. Reg. at 76,753. In prior
petitions, NMFS had evaluated whether climate change
would endanger a species by the year 2050, regardless of any
research advancements regarding climate or a specific
species. Listing Rule, 77 Fed. Reg. at 76,753 (explaining the
use of climate projections through 2050 for the ribbon seal
and polar bear). The Solicitor’s advisory letter acknowledges
          ALASKA OIL & GAS ASS’N V. PRITZKER                 23

that its interpretation represents a change in agency policy,
and it provides a thorough and reasoned explanation for its
recommendation that the Service adopt a data-driven threat
analysis for future harm. Mem. No. M-37021 at 4, 8–9. The
letter also states explicitly that the policy change seeks to
conform to federal appellate decisions requiring ESA
analyses to adhere to the statute’s “best data available”
standard. Id. at 8–9 (citing Bennett v. Spear, 520 U.S. 154,
176 (1997); Bldg. Indus. Ass’n of Superior Cal. v. Norton,
247 F.3d 1241, 1246–47 (D.C. Cir. 2001)).

    NMFS’s decision to adopt a foreseeability analysis that is
responsive to new, reliable research while accounting for
species-, threat-, and habitat-specific factors is well-reasoned
and consistent with the ESA’s mandate. On the record before
us, NMFS’s changed approach was neither arbitrary nor
capricious.

                              3.

    Next, Plaintiffs contend that NMFS failed to provide an
evidence-based explanation for the relationship between
habitat loss and the bearded seal’s survival. They argue that
NMFS has not provided sufficient evidence to demonstrate a
nexus between the loss of sea ice and the bearded seal’s risk
of future extinction. They note that at the time NMFS issued
its final listing rule, the bearded seal had not suffered
population losses, and they argue NMFS should have adopted
a “wait and see” approach before determining whether to list
the bearded seal.

    Similarly, the district court took issue with NMFS’s
disclosure that it could only provide a range for the Beringia
DPS baseline population, which would make it difficult to
24        ALASKA OIL & GAS ASS’N V. PRITZKER

measure the relationship between population declines and
loss of access to sea ice. Pritzker, 2014 WL 3726121, at *15.
The district court concluded that NMFS was unable to
provide a predicted “population reduction,” “extinction
threshold,” or “probability of reaching that threshold,” and
that without that information, there was no reasonable basis
for listing the Beringia DPS as threatened. Id. & n.69. The
district court expressed doubt that NMFS was able to conduct
a reasonable risk assessment supported by evidence when the
agency could not provide population information on the
current state of the species. Id.

    The district court’s effort to impose requirements for
which data is unavailable or does not exist is at odds with the
ESA. NMFS demonstrated that, based on the best data
available at the time of listing, a decrease in sea ice
availability would likely have a significant adverse effect on
the bearded seal population. In rejecting the Beringia DPS
final listing rule, the district court imposed ad hoc
requirements that exceed the ESA’s provisions. The district
court’s request for unobtainable, highly specified data would
require NMFS to wait until it had quantitative data reflecting
a species’ decline, its population tipping point, and the exact
year in which that tipping point would occur before it could
adopt conservation policies to prevent that species’ decline.
Uncertainty regarding the speed and magnitude of that
adverse impact, however, does not invalidate data presented
in the administrative record that reasonably supports the
conclusion that loss of habitat at key life stages will likely
jeopardize the Beringia DPS’s survival over the next 85
years.

    We recently reversed a district court’s decision to vacate
an ESA critical habitat rule because the court required highly
          ALASKA OIL & GAS ASS’N V. PRITZKER               25

specific information for which data simply did not exist. In
Alaska Oil and Gas Association v. Jewell, the district court
suggested that an agency could only designate areas
containing polar bear dens as critical habitats, as opposed to
conserving a greater amount of land to allow the bears to
roam. 815 F.3d at 555. We rejected the district court’s
imposition of additional requirements because the district
court’s “narrow construction of critical habitat runs directly
counter to the Act’s conservation purposes.” Id. We noted
that the ESA was “concerned with protecting the future of the
species, not merely the preservation of existing bears.” Id.

     The Service need not wait until a species’ habitat is
destroyed to determine that habitat loss may facilitate
extinction. In Defenders of Wildlife v. Norton, we held that
evidence of habitat loss, without a reasoned explanation
providing a causal link between loss of habitat and a species’
survival, was inadequate to support listing a species as
threatened. 258 F.3d 1136, 1143 (9th Cir. 2001). But NMFS
did not rely on habitat loss, alone, to justify its listing
decision. Instead, the agency drew upon existing research to
explain how habitat loss would likely endanger the bearded
seal. See In re Polar Bear Litig., 709 F.3d at 9–10
(distinguishing Defenders of Wildlife by noting that the
agency’s reasoned explanation regarding the impact of habitat
loss on a specific species provided an adequate basis for its
listing decision). NMFS has demonstrated that it “considered
the relevant factors and articulated a rational connection
between the facts found and the choices made.” Nw. Ecosys.
All., 475 F.3d at 1140 (quoting Nat’l Ass’n of Home Builders
v. Norton, 340 F.3d 835, 841 (9th Cir. 2003)). That is all the
ESA requires.
26        ALASKA OIL & GAS ASS’N V. PRITZKER

                              4.

    In addition to contesting the causal relationship between
loss of sea ice and the Beringia DPS’s long-term survival,
Plaintiffs contend that NMFS was required to demonstrate
that the impact of climate change on the Beringia DPS “will
be of a magnitude that places the species ‘in danger of
extinction’ by the year 2100.”           Plaintiffs’ argument
misinterprets the ESA’s requirement that an agency
demonstrate that a species will “likely become an endangered
species within the foreseeable future” before listing that
species as threatened under the Act. 16 U.S.C. § 1532(20).

    NMFS correctly contends that the ESA directs the agency
to determine the likelihood of a species’ endangerment based
on one or more statutory factors: (1) the present or threatened
destruction of a species’ habitat or range; (2) overutilization
of the species for commercial, recreational, scientific, or
educational purposes; (3) disease or predation; (4) the
inadequacy of existing regulatory mechanisms; or (5) other
natural or manmade factors affecting its continued existence.
16 U.S.C. § 1533(a)(1). Significantly, the ESA does not
require an agency to quantify population losses, the
magnitude of risk, or a projected “extinction date” or
“extinction threshold” to determine whether a species is
“more likely than not” to become endangered in the
foreseeable future. NMFS also contends that the district court
erred when it held that NMFS must demonstrate a “predicted
population reduction,” define an “extinction threshold,” and
provide information on the “probability of reaching that
threshold within a specified time.”

   NMFS is correct; neither the ESA nor our case law
requires the agency to calculate or otherwise demonstrate the
          ALASKA OIL & GAS ASS’N V. PRITZKER                 27

“magnitude” of a threat to a species’ future survival before it
may list a species as threatened. Although the phrase “likely
to become endangered” is not defined by the ESA or a
regulation, NMFS has interpreted the term “likely” to have its
common meaning (i.e., more likely than not). Indeed, most
dictionaries define “likely” to mean that an event, fact, or
outcome is probable. Likely, THE MERRIAM-WEBSTER
DICTIONARY (new ed. 2016); Likely, OXFORD ENGLISH
DICTIONARY ONLINE (3d ed. 2016); Likely, BLACK’S LAW
DICTIONARY (10th ed. 2014); see also Taniguchi v. Kan Pac.
Saipan, Ltd., 132 S. Ct. 1997, 2002–04 (2012) (discussing the
use of dictionaries to determine the ordinary or common
meaning of a word). We agree with the D.C. Circuit that
NMFS is not required to define “likely” in terms that require
specific quantitative targets. In re Polar Bear Litig., 709 F.3d
at 14–15; cf. Defs. of Wildlife, 258 F.3d at 1141–43 (declining
to adopt a quantitative definition when interpreting the phrase
“substantial portion of its range”).

    We conclude that NMFS did not misinterpret or misapply
the word “likely” when it concluded that the bearded seal was
“likely to become an endangered species within the
foreseeable future.”

                          *    *   *

   Although data regarding the bearded seal is limited,
NMFS conducted a thorough assessment based on the best
available scientific and commercial data, and it seriously
considered the comments it received prior to listing the
Beringia DPS as a threatened species. In arriving at that
conclusion, NMFS complied with the letter and spirit of the
ESA, and it afforded the public ample notice and opportunity
to participate in its rulemaking process. In light of the
28        ALASKA OIL & GAS ASS’N V. PRITZKER

robustness of NMFS’s rulemaking process, as well as our
highly deferential standard of review, we hold that NMFS’s
final rule listing the Beringia DPS as threatened was not
arbitrary or capricious, and its listing decision was supported
by substantial evidence.

                              B.

    We turn to Alaska’s argument that NMFS failed to
comply with its obligations under the ESA to provide the
State with a written justification explaining why it “fail[ed]
to adopt regulations consistent with the [state] agency’s
comments.” 16 U.S.C. § 1533(i) (“ESA Section 4(i)” or
“Section 4(i)”); see also 50 C.F.R. § 424.18. Alaska state
agencies, including the Department of Fish and Game,
Department of Environmental Conservation, Department of
Natural Resources, and Department of Law, jointly submitted
comments recommending that NMFS decline to list any sea
ice seals as threatened and to revisit the issue in 20 to 50
years.

    NMFS sent a letter to the Commissioner of the Alaska
Department of Fish and Game, the lead agency for the State,
notifying Alaska of its listing decision and identifying
sections of the final listing rule where NMFS addressed the
State’s substantive comments. Alaska argued, and the district
court agreed, that NMFS’s letter to Alaska was insufficient to
discharge its notification duties under ESA Section 4(i).
Pritzker, 2014 WL 3726121, at *10.

    The district court, however, did not have the benefit of
our opinion in Alaska Oil and Gas Association v. Jewell,
which held that Section 4(i) did not impose a separate
notification duty upon federal agencies. 815 F.3d at 562–64.
            ALASKA OIL & GAS ASS’N V. PRITZKER                       29

Relying on T-Mobile South, LLC v. City of Roswell, 135 S.
Ct. 808, 811 (2015), we held that nothing in Section 4(i)
required separate state notification—the provision only
required that the justification for rejecting a state agency’s
comments be addressed in writing. Jewell, 815 F.3d at 563.
We further held that Section 4(i) “does not foreclose cross-
referencing other publicly available documents,” and we
noted that when several state agencies submit a consolidated
comment letter, a federal agency may respond with a single
letter to the State. Id.

    The State’s arguments are foreclosed in light of our
holding in Alaska Oil and Gas Association v. Jewell.
NMFS’s final listing rule provides thorough responses to
Alaska’s substantive comments, and any issues unaddressed
in the rule are discussed in the agency’s letter to
Commissioner Campbell. Although Alaska argues that
NMFS failed to address several of its substantive comments,
the record indicates otherwise. For example, NMFS
addressed Alaska’s argument that some bearded seals did not
rely on multi-year ice in Comments 10, 24, and 32. NMFS
addressed Alaska’s argument that temperature oscillations
could result in habitat gains in Comment 8. NMFS did not
discuss in detail Alaska’s hypothesis that bearded seals could
survive in deep water because the majority of the record
evidence found that seals preferred to feed in shallower
waters, and there was no reliable data indicating that bearded
seals lived year-round in deep waters or could adapt to such
circumstances.9 Finally, NMFS adopted the position of the


    9
      Alaska argues that NMFS’s letter failed to address its resiliency
argument, which appears in Comment 9 of the Listing Rule. Although
NMFS failed to highlight Comment 9 in its letter, the state agencies’
substantive concerns were adequately addressed in the final Listing Rule.
30         ALASKA OIL & GAS ASS’N V. PRITZKER

overwhelming majority of the world’s climate scientists and
rejected Alaska’s argument that climate projections are
“hypotheses” that are not linked to observable data and that
cannot provide reasonable estimates of future climate-
change-related phenomena.

    Thus, consistent with Alaska Oil and Gas Association v.
Jewell, NMFS satisfied its Section 4(i) obligation to provide
written responses that cite to record evidence. Although
Alaska may disagree with NMFS’s resolution of conflicting
opinions and its final listing determination, the State received
the notice, opportunity, and process required by 16 U.S.C.
§§ 1533(b)(5)(A)(ii) and 1533(i). See Jewell, 815 F.3d at
563–64 (noting that a federal agency’s rejection of a state
comment does not constitute a failure to provide a substantive
response). On this record, NMFS clearly fulfilled its
procedural and substantive obligations under Section 4(i).

                              V.

     The judgment of the district court is REVERSED.
