FOR PUBLICATION

 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED COOK INLET DRIFT                No. 14-35928
ASSOCIATION; COOK INLET
FISHERMEN’S FUND,                         D.C. No.
          Plaintiffs-Appellants,    3:13-cv-00104-TMB

               v.
                                         OPINION
NATIONAL MARINE FISHERIES
SERVICE; PENNY PRITZKER, in
her official capacity as Acting
United States Secretary of
Commerce; KATHRYN
SULLIVAN, Acting Under
Secretary of Commerce and
Administrator for the National
Oceanic and Atmospheric
Administration; JAMES W.
BALSIGER, in his official
capacity as NMFS Alaska
Region Administrator,
           Defendants-Appellees,

STATE OF ALASKA,
         Intervenor-Defendant-
                     Appellee.



     Appeal from the United States District Court
              for the District of Alaska
     Timothy M. Burgess, Chief Judge, Presiding
2        UNITED COOK INLET DRIFT ASS’N V. NMFS

            Argued and Submitted August 2, 2016
                    Anchorage, Alaska

                    Filed September 21, 2016

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

                    Opinion by Judge Hurwitz


                           SUMMARY *


      Magnuson-Stevens Fishery Conservation and
                  Management Act

    The panel reversed the district court’s summary
judgment in favor of the government in an action under the
Magnuson-Stevens Fishery Conservation and Management
Act brought by two groups of commercial fishermen urging
the rejection of Amendment 12, which removed the historic
net-fishing area of Cook Inlet from the Salmon Fishery
Management Plan (“FMP”); and remanded with instructions
that judgment be entered in favor of plaintiffs.

   The panel held that the National Marine Fisheries
Service cannot exempt a fishery under its authority that
required conservation and management from an FMP
because the agency is content with State management. The
panel held that the Magnuson-Stevens Act unambiguously


  *
    This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
        UNITED COOK INLET DRIFT ASS’N V. NMFS             3

requires a Regional Fishery Management Council to create
an FMP for each fishery under its authority that requires
conservation and management. The panel further held that
the Magnuson-Stevens Act allowed delegation to a state
under the FMP, but did not excuse the obligation to adopt an
FMP when a Regional Fishery Management Council opted
for state management.         The panel concluded that
Amendment 12 was therefore contrary to law to the extent
that it removed Cook Inlet from the FMP.


                       COUNSEL

Jason T. Morgan (argued) and Beth S. Ginsberg, Stoel Rives
LLP, Seattle, Washington, for Plaintiffs-Appellants.

Ellen J. Durkee (argued) and Coby Howell, Attorneys,
Appellate Section; John C. Cruden, Assistant Attorney
General; Environment and Natural Resources Division,
United States Department of Justice, Washington, D.C.;
Caroline Park, NOAA Office of the General Counsel, Silver
Spring, Maryland; Lauren Smoker, NOAA Office of the
General Counsel, Department of Commerce, Juneau,
Alaska; for Defendants-Appellees.

Seth M. Beausang (argued), Assistant Attorney General,
Anchorage, Alaska, for Intervenor-Defendant-Appellee.
4       UNITED COOK INLET DRIFT ASS’N V. NMFS

                        OPINION

HURWITZ, Circuit Judge:

    The Magnuson-Stevens Fishery Conservation and
Management Act, 16 U.S.C. §§ 1801–91 (“Magnuson-
Stevens Act,” or “the Act”), creates a “national program for
the conservation and management of the fishery resources of
the United States.” Id. § 1801(a)(6). The Act establishes
eight Regional Fishery Management Councils, each of
which “shall” prepare a fishery management plan (“FMP”)
“for each fishery under its authority that requires
conservation and management.” Id. § 1852(a), (h)(1). The
Secretary of Commerce, acting through the National Marine
Fisheries Service (“NMFS”), then reviews each FMP or
amendment of a plan “to determine whether it is consistent
with the [Act’s] national standards, the other provisions of
this chapter, and any other applicable law,” 16 U.S.C.
§ 1854(a)(1). See Or. Trollers Ass’n v. Gutierrez, 452 F.3d
1104, 1108 (9th Cir. 2006).

    The issue for decision is whether NMFS can exempt a
fishery under its authority that requires conservation and
management from an FMP because the agency is content
with State management. The district court held that it could.
We disagree, and reverse.

                     BACKGROUND

I. Factual and Legislative Background

    Cook Inlet is one of the nation’s most productive salmon
fisheries. Its salmon are anadromous, beginning their lives
in Alaskan freshwater, migrating to the ocean, and returning
to freshwater to spawn.
        UNITED COOK INLET DRIFT ASS’N V. NMFS                 5

    In 1953, the United States entered into the International
Convention for the High Seas Fisheries of the North Pacific
Ocean. In response, Congress enacted the North Pacific
Fisheries Act of 1954 (the “1954 Act”), authorizing the
Secretary of the Interior to promulgate regulations governing
fisheries contiguous to Alaskan waters. See Pub. L. No. 83-
579, §§ 10 & 12, 68 Stat. 698, 699–700 (previously codified
at 16 U.S.C. §§ 1021–35). The Secretary then issued a
regulation prohibiting salmon net fishing in the western
waters of Alaska, but excepting Cook Inlet and two other
areas where net fishing had historically been permitted under
Alaska law; in those areas, federal regulation was to mirror
existing Alaskan regulation. 50 C.F.R. § 210.10 (repealed).

    Before 1976, the United States asserted authority only
over waters up to twelve nautical miles from the coastline,
and there was substantial concern that foreign fishers were
depleting American fisheries. See Mark H. Zilberberg, A
Legislative History of the Fishery Conservation
& Management Act of 1976 (“Legislative History”) 237–41,
352, 448–49, 455–56, 472–73, 476–81, 519 (1976). In 1976,
Congress enacted the Fishery Conservation and
Management Act (the “1976 Act”), Pub. L. No. 94-265, 90
Stat 331 (codified as amended at 16 U.S.C. §§ 1801–1891),
later renamed the Magnuson-Stevens Act. The 1976 Act
extended federal jurisdiction to 200 miles from the coastline,
id. § 101 (codified as amended at 16 U.S.C. § 1811), and
regulated foreign fishing in that area, id. §§ 201, 204
(codified as amended at 16 U.S.C. §§ 1821, 1824). States
retained jurisdiction over the first three miles from the coast,
id. § 306(a) (codified as amended at 16 U.S.C. § 1856), and
the federal government had jurisdiction over the next 197
miles, originally called the fishery conservation zone
(“FCZ”) and later named the exclusive economic zone
(“EEZ”), id. § 101 (codified as amended at 16 U.S.C.
6       UNITED COOK INLET DRIFT ASS’N V. NMFS

§ 1811). See also 16 U.S.C. § 1801(b)(1); Exclusive
Economic Zone of the United States of America, 48 Fed.
Reg. 10,605 (Mar. 10, 1983).

    The federal government manages its waters through
eight regional Councils. 16 U.S.C. § 1852. During the
debate on the 1976 Act, Senator Gravel of Alaska criticized
the concept of federal management on one side of the three-
mile line and state management on the other, because fish
freely travel across the three-mile boundary. Legislative
History 412–13, 460–67. Senator Gravel suggested that a
state should manage its federal waters under a plan approved
by the federal government. Id. at 467, 471. Senator Stevens
of Alaska, one of the bill’s managers, offered an even
broader proposal, which provided for exclusive state
management of “[t]hose fisheries capable of being managed
as a unit, which reside principally within the waters of a
single State.” Id. at 422. But, Congress instead approved a
more modest substitute offered by the bill’s other manager,
Senator Magnuson, directing Councils, if possible, to
incorporate state management measures in FMPs. Id.; 1976
Act § 305(c) (codified at 16 U.S.C. § 1855).

    In 1979, NMFS promulgated an FMP for salmon
fisheries near Alaska. See Fishery Management Plan for the
High Seas Salmon, 44 Fed. Reg. 33,250 (June 8, 1979) (the
“Salmon FMP”). The Salmon FMP divided Alaskan federal
waters into East and West Areas; Cook Inlet is in the West
Area. Id. at 33,267. With respect to the West Area, the FMP
tracked the regulations promulgated under the 1954 Act
prohibiting commercial salmon fishing except in the three
historic net-fishing areas, including Cook Inlet, which the
State would continue to manage. Id. (“These fisheries are
technically in the FCZ, but are conducted and managed by
the State of Alaska as inside fisheries.”). The decision to
        UNITED COOK INLET DRIFT ASS’N V. NMFS               7

leave these fisheries in the hands of the State was not based
on a finding that they were in good health; to the contrary,
the Salmon FMP found that “[a]ll salmon species are at
historic low levels in the Cook Inlet management area, with
chinook stocks seriously depleted.” Id. at 33,309.

    In 1983, Congress amended the Act to specify that a
Council need only prepare an FMP with respect to a fishery
“that requires conservation and management.” Pub. L. No.
97-453, § 5(4), 96 Stat. 2481, 2486 (codified as amended at
16 U.S.C. § 1852(h)(1)). The conference report explained
this amendment was intended “to clarify that the function of
the Councils is not to prepare a fishery management plan
(FMP) for each and every fishery within their geographical
areas of authority. Rather, such plans are to be developed
for those fisheries which require conservation and
management.” H.R. Conf. Rep. No. 97-982, 97th Cong., 2d
Sess., at *18.

    Alaska had proposed to amend the Act “to direct the
Secretary of Commerce to delegate authority of a domestic
fishery in the FCZ to the adjacent state . . . if . . . 1) the
fishery does not cross interstate boundaries; and 2) the State
is capable and willing to provide conservation and
management consistent with the National Standards.”
Omnibus Authorization Bill for the National Oceanic and
Atmospheric Administration: Hearings Before the S. Comm.
on Commerce, Sci. & Transp., Serial No. 97-118, 97 Cong.
310 (1982) [hereinafter Hearings] (statement of Ronald O.
Skoog, Commissioner, Alaska Department of Fish and
Game). But, this proposal was not enacted. See Pub. L. No.
97-453, § 5(4), 96 Stat. 2481, 2486 (1982).

    The Salmon FMP was revised in 1990. The revised FMP
stated that, under the regulation implementing the 1954 Act,
50 C.F.R. § 210, salmon net fishing in the West Area was
8       UNITED COOK INLET DRIFT ASS’N V. NMFS

prohibited, with the exception of the three historic net-
fishing areas, which “technically extend into the EEZ, but
. . . are conducted and managed by the State of Alaska as
nearshore fisheries.”

    In 1992, a new international convention prohibited all
fishing for anadromous fish beyond the EEZ. Convention
for the Conservation of Anadromous Stocks in the North
Pacific Ocean, art. I, III. Congress promptly implemented
that convention and repealed the 1954 Act. North Pacific
Anadromous Stocks Act of 1992, Pub. L. No. 102-567,
§§ 801–14, 106 Stat. 4309 (codified at 16 U.S.C. §§ 5001–
5012). The Secretary of Commerce then concluded that
regulations promulgated under the 1954 Act, including
50 C.F.R. § 210, no longer had statutory support, and
repealed them. Removal of Regulations, 60 Fed. Reg.
39,271, 39,272 (Aug. 2, 1995). But, the Salmon FMP was
not revised, and Alaska continued to manage the three
historic net fisheries.

    In 1995, a fishing vessel, “Mister Big,” engaged in a
massive unregulated harvest of scallops in the federal waters
of Prince William Sound. See Trawler Diane Marie, Inc. v.
Brown, 918 F. Supp. 921 (E.D.N.C. 1995). That scallop
fishery was not covered by an FMP, but the Magnuson-
Stevens Act provided that a State could regulate fishing
vessels in federal waters that were registered in that state. Id.
at 924, 926; see Pub. L. No. 98-623, § 404(4), 98 Stat. 3394,
3408 (1984) (“[A] State may not directly or indirectly
regulate any fishing vessel outside its boundaries, unless the
vessel is registered under the law of that State.”). The Mister
Big set sail from Seattle, renounced its Alaska registration,
and began fishing for scallops in the Sound. Trawler Diane
Marie, 918 F. Supp. at 924. By January 26, 1995, the quota
that Alaska set for the area, 50,000 pounds of scallops, had
        UNITED COOK INLET DRIFT ASS’N V. NMFS                  9

been harvested, so Alaska closed the scallop season and
Alaska-registered boats returned home. Id. But, the Mister
Big continued to dredge, eventually harvesting 52,000
pounds of scallops before the Secretary of Commerce
approved an emergency closure of the fishery. Id. at 925,
927. The North Pacific Council had drafted an FMP which
addressed the possibility that an unregulated vessel might
fish for scallops in the federal waters off Alaska, but had not
adopted it “because of the belief that all vessels fishing in the
EEZ would be registered in Alaska and thus bound by the
state’s regulations.” Id. at 926.

    The following year, Congress revised the provision
regarding state authority to regulate fishing vessels in federal
waters. See Sustainable Fisheries Act, Pub. L. No. 104-297,
§ 112, 110 Stat. 3559, 3595–97 (1996). After that
amendment, the Magnuson-Stevens Act now provides, in
relevant part:

        A State may regulate a fishing vessel outside
        the boundaries of the State in the following
        circumstances:

        (A) The fishing vessel is registered under the
        law of that State, and (i) there is no fishery
        management plan or other applicable Federal
        fishing regulations for the fishery in which
        the vessel is operating; or (ii) the State’s laws
        and regulations are consistent with the
        fishery management plan and applicable
        Federal fishing regulations for the fishery in
        which the vessel is operating.

        (B) The fishery management plan for the
        fishery in which the fishing vessel is
        operating delegates management of the
10      UNITED COOK INLET DRIFT ASS’N V. NMFS

       fishery to a State and the State’s laws and
       regulations are consistent with such fishery
       management plan.

16 U.S.C. § 1856(a)(3). The version of the bill reported out
of the House Committee on Resources would have
authorized Alaska to enforce its regulations in federal waters
even absent an FMP. H.R. Rep. No. 104-171, at *11–12
(1995). But, that version was not enacted. Pub. L. No. 104-
297, § 112.

II. Amendment 12

    The North Pacific Council has jurisdiction over the
federal waters of Cook Inlet. Six of its 11 voting members
are from Alaska and the remainder are from Washington and
Oregon. 16 U.S.C. § 1852(a)(1)(G), (b)(1), (b)(2)(C).

    In 2010, the North Pacific Council began a
comprehensive review of the Salmon FMP. As a result,
NMFS “realized” that Cook Inlet was “not exempt from the
FMP as previously assumed.” Council staff prepared a
discussion paper, which summarized the situation as
follows:

       The FMP is vague on the function of the FMP
       in these areas. Though the FMP broadly
       includes these three areas and the salmon and
       fisheries that occur there within the fishery
       management unit and states that management
       of these areas is left to the State under other
       Federal law, the FMP does not explicitly
       defer management of these salmon fisheries
       to the State. The FMP does not contain any
       management goals or objectives for these
       three areas or any provisions with which to
        UNITED COOK INLET DRIFT ASS’N V. NMFS            11

       manage salmon fishing. The FMP only
       refrains from extending the general fishing
       prohibition to those areas, where, as the FMP
       notes, fishing was authorized by other
       Federal law, [which has since been repealed].
       Therefore, the FMP’s reference to “other
       Federal laws” may no longer be fully
       effective.

    The North Pacific Council circulated a draft
Environmental Assessment, held five public meetings, and
took testimony. In 2011, the North Pacific Council
unanimously voted to remove the three historic net fishing
areas from the Salmon FMP. In April 2012, NMFS solicited
comments on this change, “Amendment 12,” and proposed
implementing regulations. 77 Fed. Reg. 19,605 (Apr. 2,
2012); 77 Fed. Reg. 21,716 (Apr. 11, 2012).

    Two groups of commercial fishermen, the United Cook
Inlet Drift Association and the Cook Inlet Fishermen’s Fund
(collectively, “United Cook”), submitted comments urging
the rejection of Amendment 12. The comments cited a 51%
decline since 1981 in the commercial catch of sockeye
salmon. United Cook attributed this decline to two
management failures by Alaska. First, United Cook argued
that the State had failed to address the introduction of
carnivorous northern pike into nearby lakes and streams.
Second, United Cook argued that Alaska was not properly
managing the escapement of salmon in Cook Inlet. The
Magnuson-Stevens Act requires limits on the number of fish
caught. 16 U.S.C. § 1853(a)(15). In contrast, Alaska
manages commercial salmon fishing through escapement
goals, i.e., the number of salmon allowed to “escape” past a
fishery to spawn. According to United Cook, “the State
misses the high end of its escapement goal targets as much
12      UNITED COOK INLET DRIFT ASS’N V. NMFS

as 35% of the time,” leading to a massive unharvested supply
of fish, and “has no escapement goals at all for many runs in
Cook Inlet.”

    In June 2012, NMFS issued a final Environmental
Assessment, finding that “the State is the appropriate
authority for managing Alaska salmon fisheries given the
State’s existing infrastructure and expertise,” and that “the
State’s escapement based management system is a more
effective management system for preventing overfishing
than a system [like the federal one] that places rigid numeric
limits on the number of fish that may be caught.” NMFS
also issued a finding that Amendment 12 would have no
significant impact on the environment because it would not
change the management of the fisheries. NMFS approved
Amendment 12, and, in December 2012, promulgated
implementing regulations. See Fisheries of the Exclusive
Economic Zone Off Alaska; Pacific Salmon, 77 Fed. Reg.
75,570 (Dec. 21, 2012); 50 C.F.R. § 679.2 (definition of
West Area).

III.   Procedural Background

    United Cook filed this action in 2013, challenging
Amendment 12 and its implementing regulations as contrary
to the Magnuson-Stevens Act’s requirement that a Council
prepare an FMP “for each fishery under its authority that
requires conservation and management,” 16 U.S.C.
§ 1852(h)(1). United Cook also alleged that Amendment 12
was arbitrary and capricious and contrary to the National
Environmental Policy Act, 42 U.S.C. § 4332(2)(C). The
district court granted Alaska’s motion to intervene as a
defendant, and entered summary judgment for the
government. United Cook timely appealed.
        UNITED COOK INLET DRIFT ASS’N V. NMFS                13

                       DISCUSSION

    The Magnuson-Stevens Act requires that “[e]ach
Council shall, in accordance with the provisions of this
chapter—(1) for each fishery under its authority that requires
conservation and management, prepare and submit to the
Secretary (A) a fishery management plan . . . .” 16 U.S.C.
§ 1852(h)(1). Thus, the usual initial question is whether the
fishery at issue even needs conservation and management.
See Anglers Conservation Network v. Pritzker, 139 F. Supp.
3d 102, 114–15 (D.D.C. 2015).             We review that
administrative decision under the traditional arbitrary and
capricious standard. Id. But we need not tarry over that
issue here; the government concedes that the Cook Inlet
fishery requires conservation and management.

    But, the government argues that the Act only requires an
FMP for fisheries that need federal conservation and
management, and that Cook Inlet is in good hands with
Alaska. The district court found the Act ambiguous, gave
Chevron deference to the government’s interpretation, and
found not arbitrary and capricious the agency’s decision that
federal involvement was not necessary.

    We determine whether to afford Chevron deference to an
agency interpretation of a statute under a two-step analysis.
First, we consider “whether Congress has directly spoken to
the precise question at issue.” Chevron, U.S.A., Inc. v. Nat.
Res. Def. Council, Inc., 467 U.S. 837, 842 (1984). “If the
intent of Congress is clear, that is the end of the matter.” Id.
Only “if the statute is silent or ambiguous with respect to the
specific issue,” do we go to step two, which considers
“whether the agency’s answer is based on a permissible
construction of the statute.” Id. at 843.
14      UNITED COOK INLET DRIFT ASS’N V. NMFS

    “We start, as always, with the language of the statute.”
Williams v. Taylor, 529 U.S. 420, 431 (2000). Section
1852(h)(1) of the Act provides that a Council “shall” prepare
an FMP for a fishery (1) “under its authority” that
(2) requires “conservation and management.”              The
government concedes that Cook Inlet is a fishery under its
authority that requires conservation and management. But it
argues that an FMP is only mandated by the Act when
“federal” conservation and management is required. Thus,
the government asks us to insert the word “federal” into
§ 1852(h)(1) before the phrase “conservation and
management.”

    “[W]e ordinarily resist reading words or elements into a
statute that do not appear on its face,” Bates v. United States,
522 U.S. 23, 29 (1997), and the government never
persuasively explains why we should deviate from that rule
here. See Pac. Coast Fed’n of Fishermen’s Ass’ns v. Blank,
693 F.3d 1084, 1095 (9th Cir. 2012) (rejecting a reading of
the Magnuson-Stevens Act which “requires inserting the
word ‘only’ or ‘solely’ into subsection [1853a](c)(5)”); see
also Stanton Rd. Assocs. v. Lohrey Enters., 984 F.2d 1015,
1020 (9th Cir. 1993) (stating that courts “lack . . . power” to
“read into the statute words not explicitly inserted by
Congress”). In arguing that we should insert the word
“federal” into § 1852(h)(1), the government relies heavily on
what it calls the “deferral” provision of the Act,
§ 1856(a)(3)(A)(i), which allows a state to regulate state-
licensed vessels in federal waters when no FMP exists. The
government argues that this provision assumes that NMFS
can cede regulatory authority to a state over federal waters
that require conservation and management simply by
declining to issue an FMP. But, § 1856(a)(3)(A)(i) does not
create an exception to the general obligation to issue an FMP
when a fishery requires conservation and management;
        UNITED COOK INLET DRIFT ASS’N V. NMFS                15

rather, the provision only restates the longstanding principle
that a State can regulate vessels registered under its laws in
federal waters absent federal law to the contrary. This
principle dates at least to 1976. See 1976 Act § 306(a) (“No
State may directly or indirectly regulate any fishing which is
engaged in by any fishing vessel outside its boundaries,
unless such vessel is registered under the laws of such
State.”).

    The 1996 amendment to the Magnuson-Stevens Act did
not expand that traditional state authority, but rather limited
state jurisdiction over state-registered vessels to when (i)
there is no FMP, or (ii) state law is consistent with the FMP.
See Sustainable Fisheries Act, § 112 (codified at 16 U.S.C.
§ 1856(a)(3)(A)). This “deferral provision” would be a
strange form of delegation of federal regulatory authority, as
it does not allow states to regulate vessels registered in other
states. In contrast, the next paragraph of the 1996
amendments, the so-called “delegation” provision, expressly
authorizes NMFS to “delegate[ ] management of the fishery
to a State” through an FMP, at which point the state can
regulate any fishing vessel in the federal waters at issue,
regardless of registration. Id. (codified at 16 U.S.C.
§ 1856(a)(3)(B)).

    The Act is clear: to delegate authority over a federal
fishery to a state, NMFS must do so expressly in an FMP.
16 U.S.C. § 1856(a)(3)(B). If NMFS concludes that state
regulations embody sound principles of conservation and
management and are consistent with federal law, it can
incorporate them into the FMP. Id. § 1853(b)(5). Indeed,
Amendment 12 expressly delegates management of the East
Area – certain federal waters off Alaska not including Cook
Inlet – to Alaska. Fisheries of the Exclusive Economic Zone
Off Alaska; Pacific Salmon, 77 Fed. Reg. at 75,570–71;
16       UNITED COOK INLET DRIFT ASS’N V. NMFS

50 C.F.R. §§ 679.1(i)(2) (“State of Alaska laws and
regulations that are consistent with the Salmon FMP and
with the regulations in this part apply to vessels of the United
States that are commercial and sport fishing for salmon in
the East Area of the Salmon Management Area.”), 679.3(f).
Amendment 12 could have expressly delegated management
of Cook Inlet to Alaska as well, but it did not. The
government argues removing Cook Inlet from the FMP
amounts to delegation. But, the federal government cannot
delegate management of the fishery to a State without a plan,
because a Council is required to develop FMPs for fisheries
within its jurisdiction requiring management and then to
manage those fisheries “through” those plans. 16 U.S.C.
§§ 1801(b)(4)–(5), 1852(h)(1). The “deferral” provision
covers those waters where for some reason a plan is not in
effect; it is not an invitation to a Council to shirk the statutory
command that it “shall” issue an FMP for each fishery within
its jurisdiction requiring conservation and management.

    Although we find the statutory language clear, we also
note that the legislative history of the Act belies the
government’s argument. 1 The Act makes plain that federal
fisheries are to be governed by federal rules in the national
interest, not managed by a state based on parochial concerns.
Compare 16 U.S.C. §§ 1801(a)(6) (“A national program for
the conservation and management of the fishery resources of
the United States is necessary to prevent overfishing . . . and
to realize the full potential of the Nation’s fishery

 1
     “[W]e ‘cautiously adhere’ to the practice of consulting legislative
history” at step one of a Chevron analysis, Irvine Med. Ctr. v. Thompson,
275 F.3d 823, 829 n.3 (9th Cir. 2002) (quoting Am. Rivers v. Fed. Energy
Reg. Comm’n, 201 F.3d 1186, 1196 n.16 (9th Cir. 2000)), recognizing
that “courts have no authority to enforce a principle gleaned solely from
legislative history that has no statutory reference point,” Shannon v.
United States, 512 U.S. 573, 584 (1994) (alterations omitted).
        UNITED COOK INLET DRIFT ASS’N V. NMFS               17

resources.”) and 1802(33)(A) (“The term ‘optimum’, with
respect to the yield from a fishery, means the amount of fish
which—(A) will provide the greatest overall benefit to the
Nation.”) and 1811(a) (“[T]he United States claims, and will
exercise in the manner provided for in this chapter, sovereign
rights and exclusive fishery management authority over all
fish, and all Continental Shelf fishery resources, within the
exclusive economic zone.”) with Alaska Br. 13 (“The Alaska
Constitution requires the State to manage natural resources
for the maximum benefit and use for all Alaskans.” (citing
Alaska Const. art. VIII, §§ 1–2)). Congress therefore
repeatedly rejected proposals to provide for state
management of federal fisheries without an FMP. Compare
Legislative History 422, 467, 471, with 1976 Act § 305(c);
compare Hearings, supra, at 310, with Pub. L. No. 97-453,
§ 5(4) (1982); compare H. Rep. No. 104-171 at *11–12, with
Pub. L. No. 104-297, § 112 (1996). We decline the
government’s invitation to vest in Alaska the very authority
that Congress abjured.

    Alaska argues that NMFS has discretion not to adopt an
FMP for federal waters requiring management and
conservation, because “shall” sometimes means “may.” See
Sierra Club v. Whitman, 268 F.3d 898, 904 (9th Cir. 2001).
But, that is not the general rule; we recognized in Sierra Club
that “‘shall’ in a statute generally denotes a mandatory duty.”
Id.; see also United States v. Monsanto, 491 U.S. 600, 607
(1989) (stating that by using “shall,” “Congress could not
have chosen stronger words to express its intent that
forfeiture be mandatory”); Brower v. Evans, 257 F.3d 1058,
1067 n.10 (9th Cir. 2001) (“‘Shall’ means shall.” (quoting
Ctr. for Biological Diversity v. Norton, 254 F.3d 833, 837–
38 (9th Cir. 2001))). Our holding in Sierra Club that the
Environmental Protection Agency did not have a mandatory
duty to bring enforcement actions under the Clean Water Act
18       UNITED COOK INLET DRIFT ASS’N V. NMFS

was driven by “the traditional presumption that an agency’s
refusal to investigate or enforce is within the agency’s
discretion,” and based on an “[a]nalysis of the structure and
the legislative history of the Clean Water Act.” 268 F.3d at
902, 904. No similar factors here support reading “shall” as
“may.” 2

    The government argues that § 1852(h)(1) does not
expressly require an FMP to cover an entire fishery, noting
that “the provision says nothing about the geographic scope
of plans at all.” But, the statute requires an FMP for a
fishery, a defined term. See 16 U.S.C. § 1802(13). No one
disputes that the exempted area of Cook Inlet is a salmon
fishery. But, under the government’s interpretation, it could
fulfill its statutory obligation by issuing an FMP applying to
only a single ounce of water in that fishery. We disagree.
When Congress directed each Council to create an FMP “for
each fishery under its authority that requires conservation
and management,” id. § 1852(h)(1), it did not suggest that a
Council could wriggle out of this requirement by creating

 2
     Alaska also argues that, if we fail to add the word “federal” before
“conservation and management” in § 1852(h)(1), NMFS will be forced
to issue an FMP for every fishery, because all fisheries require some
conservation and management. However, the legislative history of the
Act directly refutes this argument. A previous version of the statute
required an FMP for every fishery under a Council’s authority. In 1983,
Congress amended the statute to specify that an FMP is necessary only
where a fishery “requires conservation and management.” Pub. L. No.
97-453 § 5(4), 96 Stat. 2481, 2486 (codified as amended at 16 U.S.C.
§ 1852(h)(1)). If every fishery required some type of conservation and
management, this amendment would amount to a nullity. But, “[w]hen
Congress acts to amend a statute, we presume it intends its amendment
to have real and substantial effect.” Stone v. I.N.S., 514 U.S. 386, 397–
98 (1995)). The amendment thus indicates Congress understood that
some fisheries might not require conservation or management.
         UNITED COOK INLET DRIFT ASS’N V. NMFS                       19

FMPs only for selected parts of those fisheries, excluding
other areas that required conservation and management. See
id. § 1853(a) (setting out the required contents of FMPs). 3

    Finally, the government argues that its interpretation is
supported by National Standards 3 and 7 in the Magnuson-
Stevens Act, 16 U.S.C. § 1851(a)(3), (7), and the
implementing guidelines for those standards, 50 C.F.R.
§§ 600.305–355. But, the National Standards only govern
the contents of an FMP, not the decision whether to issue
one. See 16 U.S.C. § 1851(a) (requiring that FMPs “be
consistent with the following national standards for fishery
conservation and management”).           The government’s
advisory guidelines fare no better, as they do not have the
force of law. Id. § 1851(b).

                          CONCLUSION

    The Magnuson-Stevens Act unambiguously requires a
Council to create an FMP for each fishery under its authority
that requires conservation and management. The Act allows
delegation to a state under an FMP, but does not excuse the

  3
     The government also appears to argue that it fully discharged its
statutory obligation when the Salmon FMP was adopted in 1990, because
the FMP included Cook Inlet (albeit by placing it under Alaska’s
authority), and that it was thereafter free under the Act to remove any
parts of the West Area from the FMP. But, removing a fishery from an
FMP is no different than excluding that fishery from the start. An
amendment to an FMP, like the FMP itself, must conform to the statutory
scheme. See 16 U.S.C. §§ 1852(h)(1) (“Each Council shall . . . prepare
and submit to the Secretary . . . (B) amendments to each such plan that
are necessary.”); 1854(a)(1) (requiring the Secretary to review an FMP
amendment “to determine whether it is consistent with the national
standards, the other provisions of this chapter, and any other applicable
law”).
20       UNITED COOK INLET DRIFT ASS’N V. NMFS

obligation to adopt an FMP when a Council opts for state
management. Amendment 12 is therefore contrary to law to
the extent it removes Cook Inlet from the FMP. 4 We reverse
the judgment of the district court and remand with
instructions that judgment be entered in favor of United
Cook.

     REVERSED and REMANDED.




 4
     Because Congress has spoken clearly, we need not reach Chevron
step two. And, because we conclude that Amendment 12 is contrary to
law with respect to its removal of Cook Inlet from the FMP, we need not
address United Cook’s other challenges to the Amendment.