                   FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

KLAMATH SISKIYOU WILDLANDS               
CENTER; UMPQUA WATERSHEDS;
CASCADIA WILDLANDS PROJECT,
                Plaintiffs-Appellants,
                  v.
LYNDA BOODY, in her official
capacity as Glendale Field
Manager,
                           Defendant,
                 and                          No. 06-35214
BUREAU OF LAND MANAGEMENT, an
agency of the United States                    D.C. No.
                                             CV-03-03124-JPC
Department of the Interior;
KATRINA SYMONS, in her official                 OPINION
capacity as Glendale Field
Manager; WILLIAM HAIGH, in his
official capacity as South River
Field Office Manager on the
Roseburg District, BLM,
              Defendants-Appellees,
D.R. JOHNSON LUMBER COMPANY,
an Oregon corporation,
              Defendant-intervenor-
                            Appellee.
                                         
        Appeal from the United States District Court
                 for the District of Oregon
        John P. Cooney, Magistrate Judge, Presiding

                   Argued and Submitted
           October 16, 2006—Seattle, Washington

                             18221
18222      KLAMATH SISKIYOU WILDLANDS v. BLM
                Filed November 6, 2006

   Before: Dorothy W. Nelson, David R. Thompson, and
             Richard A. Paez, Circuit Judges.

             Opinion by Judge D.W. Nelson
            KLAMATH SISKIYOU WILDLANDS v. BLM          18225


                        COUNSEL

Stephanie M. Parent, Pacific Environmental Advocacy Cen-
ter, Portland, Oregon, and Erin Madden, Portland, Oregon,
briefed for the appellants. Ms. Parent argued for the appel-
lants.

Brian Perron, U.S. Department of the Interior, Portland, Ore-
gon, Sue Ellen Wooldridge, Lisa E. Jones, Brian C. Toth, and
Anna T. Katselas, U.S. Department of Justice, Washington,
D.C., briefed for the government appellees. David C. Shilton,
U.S. Department of Justice, Washington, D.C., argued for the
government appellees.

Scott W. Horngren and Shay S. Scott, Haglund, Kelley, Horn-
gren, Jones & Wilder LLP, Portland, Oregon, briefed for the
intervenor-appellee. Mr. Scott argued for the intervenor-
appellee.
18226         KLAMATH SISKIYOU WILDLANDS v. BLM
                         OPINION

D.W. NELSON, Senior Circuit Judge:

  Klamath Siskiyou Wildlands Center, Umpqua Watersheds,
and Cascadia Wildlands Project (collectively, “KS Wild”)
appeal the district court’s finding that the Bureau of Land
Management’s (“BLM’s”) 2001 and 2003 annual species
review decisions regarding the red tree vole were lawful. KS
Wild also appeals the district court’s finding that the Cow
Catcher and Cottonsnake timber sales were valid and should
be permitted to go forward. The district court determined that
BLM’s decisions did not violate the Federal Land Policy &
Management Act (“FLPMA”) or the National Environmental
Policy Act (“NEPA”). We reverse the judgment of the district
court and direct the entry of an injunction enjoining the Cow
Catcher and Cottonsnake timber sales from going forward.

        I.   FACTUAL & PROCEDURAL HISTORY

   In 1994, the federal government adopted a comprehensive
forest management plan known as the Northwest Forest Plan
(“NWFP”). The NWFP amended the resource management
plans for many BLM districts, including the Roseburg and
Medford districts at issue in this case, by allocating lands
amongst several administrative categories throughout 24.4
million acres in the Pacific Northwest.

   In addition to the land allocations, the NWFP also estab-
lished Survey and Manage requirements to provide additional
protections for species that might not be adequately protected
by the broad-scale land allocations. The NWFP’s Survey and
Manage requirements protected over 400 species of amphibi-
ans, mammals, bryophytes, mollusks, vascular plants, fungi,
lichens, and arthropods within the northern spotted owl range.
The red tree vole was one of the protected species.

  In 2001, BLM and the Forest Service amended the NWFP
by issuing the Record of Decision for Amendments to the
               KLAMATH SISKIYOU WILDLANDS v. BLM                  18227
Northwest Forest Plan (“2001 ROD”). The agencies prepared
a Final Supplemental Environmental Impact Statement (“2000
FSEIS”) providing evidentiary support and extensive scien-
tific analysis for the 2001 ROD.

   The 2001 ROD made two significant changes to the NWFP
pertinent to this case. First, it modified the Survey and Man-
age species protections by expanding from a four-category to
a six-category classification system. It assigned the red tree
vole to Category C, which requires (1) management of high-
priority sites, (2) pre-disturbance surveys, and (3) strategic
surveys prior to any agency action that would disturb the spe-
cies’ habitat. Second, the 2001 ROD created the Annual Spe-
cies Review (“ASR”) process, which requires BLM to
acquire, evaluate, and apply new information to implement
changes or refinements to the Survey and Manage classifica-
tions.

   On June 14, 2002, after completing its first ASR regarding
the red tree vole, BLM issued a memorandum downgrading
the red tree vole’s Survey and Manage classification from
Category C to Category D (the “2001 ASR Decision”).1 In
contrast to the protections afforded species listed under Cate-
gory C, BLM is not required to conduct pre-disturbance sur-
veys for species listed under Category D. On December 19,
2003, BLM issued a second memorandum removing the
vole’s Survey and Manage designation entirely (the “2003
ASR Decision”).2

  On June 16, 2003, BLM issued an environmental assess-
ment (“EA”) for the Cow Catcher timber sale. In accordance
  1
     The memorandum was formally issued in June, 2002, yet the change
was the result of the 2001 ASR, and it is referred to as the “2001 ASR
Decision.”
   2
     Both the 2001 and 2003 ASR Decisions (collectively the “ASR Deci-
sions”) applied only to the vole’s mesic (central) zone of its range. The
timber sales at issue in this case are both within this zone.
18228        KLAMATH SISKIYOU WILDLANDS v. BLM
with its 2001 ASR Decision downgrading the vole to Cate-
gory D, BLM did not conduct pre-disturbance surveys for the
vole. On August 25, 2003, BLM issued a Finding of No Sig-
nificant Impact (“FONSI”) for the Cow Catcher sale, which
was ultimately awarded to D.R. Johnson Lumber Co. (“D.R.
Johnson”), the defendant-intervenor in this case.

   Also in June, 2003, BLM released an EA for the Cotton-
snake timber sale in which BLM acknowledged that if any
vole nests existed within the units to be harvested “they would
likely be destroyed.” On August 28, 2003, BLM issued a
FONSI for the Cottonsnake sale, which has not yet been
awarded.

   On December 30, 2003, KS Wild filed a complaint, seeking
to enjoin the Cow Catcher and Cottonsnake timber sales, and
to invalidate the ASR Decisions on the grounds that (1) they
violated FLPMA, (2) they were invalid under NEPA, and (3)
they were the product of arbitrary and capricious agency
action. The district court issued a preliminary injunction, and
both parties moved for summary judgment. On June 6, 2005,
Magistrate Judge Cooney issued his Findings and Recommen-
dations regarding the parties’ cross-motion for summary judg-
ment, and on February 21, 2006, the district court issued a
final order, adopting the Findings and Recommendations in
part, and denying relief on KS Wild’s FLPMA, NEPA, and
arbitrary and capricious claims. In light of these findings, the
court also found no basis upon which to enjoin BLM or D.R.
Johnson from going forward with the timber sales. KS Wild
timely appealed to this court.

  We conclude that the district court erred in granting sum-
mary judgment in favor of BLM. The 2001 and 2003 ASR
Decisions are invalid under both FLPMA and NEPA, and
because we set the decisions aside on these grounds, we need
not reach KS Wild’s arbitrary and capricious claim.
               KLAMATH SISKIYOU WILDLANDS v. BLM                  18229
                II.   STANDARD OF REVIEW

   We review the district court’s grant of summary judgment
de novo. Native Ecosystems Council v. U.S. Forest Serv., 428
F.3d 1233, 1238 (9th Cir. 2005). Agency decisions that alleg-
edly violate NEPA and FLPMA are reviewed under the
Administrative Procedure Act (“APA”), and may be set aside
if they are “arbitrary, capricious, an abuse of discretion, or
otherwise not in accordance with law.” Id. (quoting 5 U.S.C.
§ 706(2)(A) (2005)).

                         III.   ESTOPPEL

   We must first decide whether two of the appellants, Klam-
ath Siskiyou Wildlands Center and Umpqua Watersheds
(“KSWC/UW”), should be estopped from bringing this appeal.3
D.R. Johnson alleges—in an argument not joined by BLM—
that KSWC/UW should be estopped on grounds of judicial
estoppel and laches. We reject both arguments.

  1.   Judicial Estoppel

   [1] “Judicial estoppel is an equitable doctrine that precludes
a party from gaining an advantage by asserting one position,
and then later seeking an advantage by taking a clearly incon-
sistent position.” Hamilton v. State Farm Fire & Cas. Co.,
270 F.3d 778, 782 (9th Cir. 2001). Thus, “an inconsistent fac-
tual or legal position is a threshold requirement of the doc-
trine.” United States v. Lence, 455 F.3d 1047, 1051 (9th Cir.
2006).
  3
    The third appellant in this case, Cascadia Wildlands Project, was not
a party to the previous proceedings upon which D.R. Johnson bases its
estoppel arguments. Instead, D.R. Johnson argues Cascadia has no stand-
ing to challenge the Cow Catcher sale because it failed to exhaust its
administrative remedies. Because we hold that KSWC/UW are not estop-
ped from pursuing this appeal, and KSWC/UW’s standing is not in ques-
tion, we need not address D.R. Johnson’s standing argument regarding
Cascadia.
18230        KLAMATH SISKIYOU WILDLANDS v. BLM
   D.R. Johnson argues that in a previous action, Northwest
Ecosystem Alliance v. Rey, 2006 WL 44361 (W.D. Wash. Jan.
9, 2006), KSWC/UW successfully invalidated a 2004 Record
of Decision (“2004 ROD,” which temporarily replaced the
2001 ROD) on the basis that the 2001 ROD should remain in
effect. D.R. Johnson alleges KSWC/UW should be estopped
from arguing in the instant case that the 2001 and 2003 ASR
Decisions are unlawful. D.R. Johnson’s argument is without
merit.

   In Rey, KSWC/UW sought to preserve the ASR process,
arguing that additional time was needed to give the process a
chance to work. However, in the instant case, KS Wild is
challenging the ASR Decisions regarding the red tree vole,
not the entire ASR process. KSWC/UW argued in Rey that
the 2004 ROD, which completely eliminated the Survey and
Manage strategy, was not supported by a thorough, reasoned
analysis regarding the likely impacts of the decision. See Rey,
2006 WL 44361, at *2. Asserting that the 2001 ROD is an
effective forest management strategy is quite different than
arguing that all agency actions ostensibly taken pursuant to
that strategy are lawful. Moreover, the only reasonable relief
that KSWC/UW could seek under the Administrative Proce-
dure Act in Rey was to have the district court reinstate the
2001 ROD. Paulsen v. Daniels, 413 F.3d 999, 1008 (9th Cir.
2005) (“The effect of invalidating an agency rule is to rein-
state the rule previously in force.”).

  [2] In Rey KSWC/UW supported the 2001 ROD and the
ASR process only insofar as they sought to invalidate the
2004 ROD. Therefore, the record indicates that KSWC/UW
have not taken a “clearly inconsistent position” in this action,
and judicial estoppel does not apply.

  2.    Laches

   [3] D.R. Johnson’s laches argument also fails. To demon-
strate laches, a party must establish “(1) lack of diligence by
             KLAMATH SISKIYOU WILDLANDS v. BLM            18231
the party against whom the defense is asserted, and (2) preju-
dice to the party asserting the defense.” Apache Survival
Coalition v. United States, 21 F.3d 895, 905 (9th Cir. 1994).
D.R. Johnson has established neither requirement.

   [4] D.R. Johnson alleges that KSWC/UW showed lack of
diligence by “abandoning” an earlier action, Oregon Natural
Resource Council Fund v. Veneman, Civ. No. 02-983-AA (D.
Or.), in which they challenged the 2001 ROD. However,
Veneman was dismissed without prejudice on December 15,
2003, id., and KS Wild filed its complaint in the instant case
on December 30, 2003. This does not show a lack of dili-
gence.

   [5] Moreover, D.R. Johnson alleges it has been prejudiced
by the “delay” because it has needed the timber from the Cow
Catcher sale throughout the pendency of this litigation. This
is not the type of irreversible harm that is properly considered
in a laches analysis. Neighbors of Cuddy Mountain v. U.S.
Forest Serv., 137 F.3d 1372, 1381 n.9 (9th Cir. 1998) (“We
know of no case in which a private company’s economic loss
was considered pertinent to the analysis of a laches
defense.”); Apache Survival Coalition, 21 F.3d at 912 (hold-
ing that prejudice must be “what Congress defines as preju-
dice. The primary concern is whether the harm that Congress
sought to prevent . . . is now irreversible.”) (internal quota-
tions omitted). Furthermore, laches is disfavored in environ-
mental cases because the public at-large, and not just the
plaintiffs, will be harmed by environmental damage. Id. at
905. Therefore, laches does not estop KSWC/US from bring-
ing this appeal.

                IV.   THE FLPMA CLAIM

   The Federal Land Policy & Management Act (“FLPMA”),
43 U.S.C. §§ 1701-1785 (2006), establishes requirements for
land use planning on public land, including the land covered
by the NWFP. FLPMA requires that BLM, under the Secre-
18232       KLAMATH SISKIYOU WILDLANDS v. BLM
tary of the Interior, “develop, maintain, and when appropriate,
revise land use plans” to ensure that land management be con-
ducted “on the basis of multiple use and sustained yield.” 43
U.S.C. §§ 1701(a)(7), 1712(a); see also Kern v. Bureau of
Land Mgmt., 284 F.3d 1062, 1067 (9th Cir. 2002) (holding
that FLPMA “requires the BLM to prepare [resource manage-
ment plans] for the various districts under its control.”). The
process for developing, maintaining, and revising resource
management plans is controlled by federal regulations at 43
C.F.R. §§ 1601.0-1610.8 (2006).

   [6] Under FLPMA, if BLM wishes to change a resource
management plan, it can only do so by formally amending the
plan pursuant to 43 C.F.R. § 1610.5-5. Section 1610.5-5
states, in pertinent part:

    . . . An amendment shall be initiated by the need to
    consider monitoring and evaluation findings, new
    data, new or revised policy, a change in circum-
    stances or a proposed action that may result in a
    change in the scope of resource uses or a change in
    the terms, conditions and decisions of the approved
    plan. An amendment shall be made through an envi-
    ronmental assessment of the proposed change, or an
    environmental impact statement, if necessary, public
    involvement as prescribed in § 1610.2 of this title,
    interagency coordination and consistency determina-
    tion as prescribed in § 1610.3 of this title and any
    other data or analysis that may be appropriate. . . .

Id. Thus, BLM must amend a management plan when an
action is proposed that changes either “the scope of resource
uses” or the “terms, conditions and decisions” of the plan.

  [7] Not all changes to a plan, however, require formal
amendment. BLM may take steps to “maintain” plans under
43 C.F.R. § 1610.5-4, which permits maintenance
            KLAMATH SISKIYOU WILDLANDS v. BLM           18233
    as necessary to reflect minor changes in data. Such
    maintenance is limited to further refining or docu-
    menting a previously approved decision incorporated
    in the plan. Maintenance shall not result in expan-
    sion in the scope of resource uses or restrictions, or
    change the terms, conditions, and decisions of the
    approved plan. Maintenance is not considered a plan
    amendment and shall not require the formal public
    involvement and interagency coordination process
    described under §§ 1610.2 and 1610.3 of this title or
    the preparation of an environmental assessment or
    environmental impact statement. Maintenance shall
    be documented in plans and supporting records.

43 C.F.R. § 1610.5-4.

   BLM concedes it did not take formal steps to amend the
2001 ROD. Instead, BLM asserts the ASR Decisions maintain
the 2001 ROD in accordance with § 1610.5-4, and that the
requirements of § 1610.5-5 are inapposite. Accordingly, BLM
argues it was not required to formally amend the resource
management plans, nor was it required to comply with the
environmental assessment, environmental impact statement,
public disclosure, and interagency coordination requirements
in § 1610.5-5.

   [8] We disagree. It is clear the 2001 and 2003 ASR Deci-
sions amended the resource management plans. They resulted
from the need to consider new information regarding the red
tree vole and they changed the terms and conditions of the
plans without complying with § 1610.5-5. Therefore, the ASR
Decisions violated FLPMA.

   [9] As explained in Part II, supra, the 2001 ASR Decision
downgraded the red tree vole’s Survey and Manage designa-
tion from Category C to Category D, and the 2003 Decision
removed the red tree vole from Survey and Manage protection
entirely. The ASR Decisions cannot reasonably be defined as
18234       KLAMATH SISKIYOU WILDLANDS v. BLM
“plan maintenance” under FLPMA because the decisions—
even if made pursuant to the ASR process—do nothing short
of “amend” the resource management plans.

   First, §§ 1610.5-4 (defining plan maintenance actions) and
1610.5-5 (defining plan amendments) are not equal in scope:
the former is more narrow. Section 1610.5-4 limits plan main-
tenance to actions that “reflect minor changes in data” and are
“limited to further refining or documenting a previously
approved decision incorporated in the plan.” In contrast,
§ 1610.5-5 requires plan amendments whenever there is a
“need to consider monitoring and evaluation findings, new
data, new or revised policy, [or] a change in circumstances.”

   BLM states the ASR Decisions were based on data 80% of
which was new. It is plainly unreasonable to assert that this
qualifies as a minor change in data under § 1610.5-4. More-
over, by comparing § 1610.5-4 with § 1610.5-5, it is evident
the latter captures a wider spectrum of agency action. These
provisions were created as complements, and taken together
they ensure that whenever resource management plans are
changed in any meaningful way, the changes must be made
via amendment (i.e., supported by scientific environmental
analysis and public disclosure). This is consistent with
FLPMA’s requirement that BLM ensure the “views of the
general public” and “third-party participation” are adequately
incorporated into the land planning process. See 43 U.S.C.
§ 1701(a)(5); 43 C.F.R. § 1610.2. This interpretation is also
supported by provisions of FLPMA that require BLM to man-
age public lands in accordance with resource management
plans once they have been established. See 43 U.S.C.
§ 1732(a); 43 C.F.R. § 1610.5-3(a); see also Norton v. S. Utah
Wilderness Alliance, 542 U.S. 55, 69 (2004) (observing that
the statutory directive in 43 U.S.C. § 1732(a) “prevent[s]
BLM from taking actions inconsistent with the provisions of
a land use plan.”).

  Second, § 1610.5-5 clearly requires a formal plan amend-
ment anytime a proposed action changes a “term, condition,
            KLAMATH SISKIYOU WILDLANDS v. BLM            18235
or decision” of a resource management plan. BLM argues that
the Survey and Manage designations created by the 2001
ROD were not intended as a rigid set of requirements that
would remain the same over the life of the resource manage-
ment plans, and that the ASR Decisions did not change the
terms of the 2001 ROD because shifting species between Sur-
vey and Manage designations was expected.

   BLM is partly correct: the 2001 ROD contemplated that
moving a species from one survey strategy to another or drop-
ping Survey and Manage protection for any species whose
status is determined to be more secure than originally pro-
jected could occur under the plan. However, merely because
the 2001 ROD contemplated this type of change, it does not
necessarily follow that all contemplated changes fall under the
narrow definition of plan maintenance in § 1610.5-4. If that
were the law, BLM could circumvent the mandates of
§ 1610.5-5 (i.e., requiring environmental assessments and
impact statements, public disclosure, etc.) by merely design-
ing a management plan that “contemplates” a wide swath of
future changes. Not only would such a strategy flip the regu-
latory scheme created by §§ 1610.5-4 and 1610.5-5 on its
head by defining plan maintenance broadly and plan amend-
ments narrowly, it would render nugatory the provisions of
FLPMA requiring BLM to act in accordance with established
resource management plans. 43 U.S.C. § 1732(a); 43 C.F.R.
§ 1610.5-3.

   It is readily apparent that the ASR Decisions altered the
terms and conditions of the Roseburg and Medford districts’
resource management plans. Prior to the decisions, BLM was
required to manage high-priority red tree vole sites, conduct
pre-disturbance surveys to discover additional sites, and
create a ten-acre buffer zone around each known site for every
proposed timber sale. In contrast, after the decisions, BLM is
not required to take steps to discover vole sites within a pro-
posed harvest area. When it announced the Cottonsnake tim-
ber sale, BLM even recognized that vole surveys were no
18236        KLAMATH SISKIYOU WILDLANDS v. BLM
longer required prior to logging, and if any undiscovered vole
nests occurred within the units to be logged, they would likely
be destroyed.

   If BLM can modify the protection afforded a species under
a resource management plan as dramatically as it has here—
without complying with § 1610.5-5—BLM could ultimately
remove all the Survey and Manage designations without ever
conducting another EA or EIS, and without providing public
disclosure. Such steps would undoubtedly run contrary to
both the goals and language of FLPMA.

   KS Wild urges us to also hold that the ASR Decisions vio-
late § 1610.5-5 because changing the vole’s Survey and Man-
age status resulted in a “change in the scope of resource uses.”
Because the ASR Decisions potentially increased the amount
of timber to be harvested (measured as the Probable Sale
Quantity (“PSQ”)), KS Wild argues that the ASR Decisions
should be deemed “amendments” on this basis alone.

   We disagree. The PSQ is only a “rough approximation” of
annual average timber sale volume. Although eliminating Sur-
vey and Manage protections for the vole will likely affect the
PSQ, the 2000 FSEIS noted that “Alternatives 1 and 2 of this
SEIS are estimated to achieve 94 and 96 percent of the
declared PSQ level, respectively, well within the ‘rough
approximation’ and ‘uncertainty’ parameters” set forth in the
NWFP. See FSEIS for Amendment to the Survey and Man-
age, Protection Buffer, and other Mitigation Measures Stan-
dards and Guidelines, Volume I - Chpts. 1-4 at 88 (“2000
FSEIS Standards and Guidelines”). The 2001 ROD ultimately
adopted Alternative 1, and Alternative 2, as explained infra,
closely resembles the 2001 and 2003 ASR Decisions. While
the ASR Decisions may change the PSQ, the “scope of the
resource uses” is still within the “rough approximation” set
forth in the resource management plans and contemplated in
the 2000 FSEIS Standards and Guidelines.
             KLAMATH SISKIYOU WILDLANDS v. BLM             18237
   [10] Therefore, while we conclude the ASR Decisions vio-
lated § 1610.5-5, we do not base that finding on the “change
in resource uses” provision. Changing the terms and condi-
tions of the resource management plans are alone sufficient to
require compliance with § 1610.5-5.

   Third, the crux of BLM’s argument is that the ASR pro-
cess, and all decisions made pursuant to it, satisfy the environ-
mental assessment, environmental impact statement, public
involvement, and interagency cooperation requirements of
FLPMA because the ASR process is supported by the 2000
FSEIS. However, even if adaptive management modifications
were contemplated by the 2000 FSEIS, there must be limits
to how dramatic “modifications” can be before they are
deemed “amendments.” Otherwise, as explained above,
resource management plans could be designed in such an
open-ended manner as to render § 1610.5-5 ineffectual.

   More importantly, although BLM emphasizes the 2000
FSEIS expected Survey and Manage designations to be
adjusted over the short-term for some species under the ASR
process, there is no indication the red tree vole was one of
those species. In fact, the opposite is true. The 2000 FSEIS
clearly stated that red tree voles require extensive additional
research and protection before any conclusions regarding the
impact of logging could be reached. Before ultimately decid-
ing to designate the vole as a Category C species, the 2000
FSEIS conducted an extensive taxonomical analysis of voles.
The experts considered four possible strategies, one of which,
“Alternative 2,” would have initially placed voles in Category
D then phased them out of Survey and Manage protection
after five years. The 2000 FSEIS resoundedly rejected this
strategy, stating that:

    Alternative 2 results in substantial effects and uncer-
    tainty on the future status of the red tree vole. . . .
    The requirement to only manage known sites . . . and
    to not conduct pre-disturbance surveys for future
18238       KLAMATH SISKIYOU WILDLANDS v. BLM
    habitat-disturbing activities would increase the risk
    of losing sites needed to maintain connectivity
    throughout all three red tree vole distribution zones.
    This, in turn, would increase the risk of isolation of
    red tree vole populations and likely reduce gene
    flow. . . . [Thus,] Alternative 2 would provide inade-
    quate habitat to maintain stable populations of the
    species in all three red tree vole distribution zones
    due to the lack of connectivity . . . .

2000 FSEIS Standards and Guidelines at 392.

   Notably, BLM’s 2001 and 2003 ASR Decisions change the
vole’s Survey and Manage designation in the same way it
would have changed under Alternative 2, which was flatly
rejected in the 2000 FSEIS. It is unreasonable for BLM to
argue that the 2000 FSEIS supports the ASR Decisions, and
that the decisions do not amount to changes in the “terms” or
“decisions” of the resource management plans, given the
unequivocal rejection of Alternative 2.

   Finally, BLM emphasizes that adaptive management is at
the heart of the NWFP, and flexibility is a necessary element
of this strategy. BLM contends that pursuant to this adaptive
management approach, new information, which was discov-
ered after the 2000 FSEIS, prompted the ASR Decisions. Not
only does this weaken BLM’s argument that the 2000 FSEIS
supports the ASR Decisions, but the 2000 FSEIS clearly
stated that even if changes to the vole’s Survey and Manage
designation are made, the data necessary to make such
changes would not be available for several years:

    Alternative 2 creates uncertainty in how the species
    would be managed following the five-year interval.
    Given our limited knowledge of red tree vole popu-
    lation dynamics and ecology, the five-year time-
    frame is not likely to be sufficient for completion of
    the studies necessary to make an informed recom-
            KLAMATH SISKIYOU WILDLANDS v. BLM           18239
    mendation to the species[’] future disposition. . . .
    Information on the genetic variation between these
    small isolated populations, combined with studies of
    red tree vole population trend[s], longevity, demo-
    graphics, and population densities require collection
    of data over several generations of red tree voles
    (more than five years).

2000 FSEIS Standards and Guidelines at 392-93.

   Given the 2000 FSEIS’ unequivocal rejection of Alterna-
tive 2, BLM cannot sustain the argument that the FSEIS sup-
ported the ASR Decisions, especially when the 2001 ASR
Decision came within a matter of months of the 2001 ROD,
and both ASR Decisions occurred well before data sufficient
to warrant an amendment in the vole’s status was available.

   [11] BLM’s ASR Decisions, even if ostensibly plan main-
tenance actions made pursuant to the ASR process, violate
FLPMA because the dramatic change in policy regarding the
vole’s Survey and Manage designation cannot be reasonably
defined as anything other than a change in a “term or condi-
tion” in the resource management plans.

                 V.   THE NEPA CLAIM

   [12] The National Environmental Policy Act (“NEPA”)
requires agencies considering “major Federal actions signifi-
cantly affecting the quality of the human environment” to per-
form an “environmental impact statement.” 42 U.S.C.
§ 4332(2)(C) (2006); Nw. Environ. Advocates v. Nat’l Marine
Fisheries Serv., 460 F.3d 1125, 1132 (9th Cir. 2006). An
environmental impact statement (“EIS”) “shall provide full
and fair discussion of significant environmental impacts and
shall inform decisionmakers and the public of the reasonable
alternatives which would avoid or minimize adverse impacts
or enhance the quality of the human environment.” 40 C.F.R.
§ 1502.1; Nw. Environ. Advocates, 460 F.3d at 1134. By
18240         KLAMATH SISKIYOU WILDLANDS v. BLM
focusing agency and public attention on the environmental
effects of proposed agency action, “NEPA ensures that the
agency will not act on incomplete information, only to regret
its decision after it is too late to correct.” Marsh v. Or. Natu-
ral Res. Council, 490 U.S. 360, 371 (1989) (quoting 42
U.S.C. § 4321 and 40 C.F.R. § 1502.9(c)).

   Under NEPA, agencies must not only perform EISs prior
to taking federal action, but agencies must perform supple-
mental EISs whenever

       (i) The agency makes substantial changes in the
       proposed action that are relevant to environmental
       concerns; or

       (ii) There are significant new circumstances or
       information relevant to environmental concerns and
       bearing on the proposed action or its impacts.

40 C.F.R. § 1502.9(c)(1).

  1.    “Substantial Changes”           in    the     Resource
        Management Plans

   BLM concedes it did not conduct a “NEPA analysis”
(requiring it to, inter alia, perform an EA, issue an EIS or a
Finding of No Significant Impact, and seek public input) prior
to implementing its 2001 and 2003 ASR Decisions regarding
the red tree vole. BLM argues that changes in agency policy
do not always require NEPA analysis. This is correct. The
Supreme Court opined in Marsh that “an agency need not
supplement an EIS every time new information comes to light
after the EIS is finalized.” 490 U.S. at 373. However, NEPA
requires an agency to take a “hard look” at potential environ-
mental consequences before taking action, Baltimore Gas &
Elec. Co. v. Natural Res. Def. Council, Inc., 462 U.S. 87, 97
(1983), and if the proposed action might significantly affect
the quality of the environment, a supplemental EIS is
            KLAMATH SISKIYOU WILDLANDS v. BLM           18241
required. Marsh, 490 U.S. at 374; Price Road Neighborhood
Ass’n v. U.S. Dep’t of Transp., 113 F.3d 1505, 1509 (9th Cir.
1997).

   [13] BLM contends the ASR Decisions were not agency
“actions” but merely implementations of an already
established—and EIS-supported—agency policy (i.e., the
ASR process). This argument sounds suspiciously similar to
BLM’s attempt to define the decisions as plan maintenance
actions rather than plan amendments under FLPMA, and it
fails for the same reasons: (1) BLM’s actions amend, not
merely maintain, the resource management plans, and (2) the
ASR Decisions were rejected in the 2000 FSEIS. Indeed, for
reasons explained in Part IV, supra, the ASR decisions
changed the resource management plans substantially, and
BLM was required to conduct NEPA analyses prior to imple-
menting those changes.

   BLM contends the Supreme Court’s decision in S. Utah
Wilderness Alliance, 542 U.S. 55 (2004) (“SUWA”), requires
us to treat the 2001 ROD, and not the ASR Decisions, as the
final “agency action.” If true, this would change our analysis
considerably because the NEPA requirements only apply to
“major Federal actions.” SUWA, 542 U.S. at 72 (quoting 42
U.S.C. § 4332(2)); see also Marsh, 490 U.S. at 374 (EIS sup-
plementation is necessary only “if there remains major Fed-
eral action to occur”). However, SUWA does not support
BLM’s position; indeed, it weakens it.

   In SUWA, environmental groups sought to compel BLM to
perform a supplemental NEPA analysis in an area where a
recent increase in off-road vehicle use had affected the envi-
ronment. The Supreme Court disagreed with the environmen-
tal groups, opining:

    although the “[a]pproval of a [land use plan]” is a
    “major Federal action” requiring an EIS, 43 CFR
    § 1601.0-6 (2003), that action is completed when the
18242          KLAMATH SISKIYOU WILDLANDS v. BLM
       plan is approved. The land use plan is the proposed
       action contemplated by the regulation. There is no
       ongoing major Federal action that could require sup-
       plementation (though BLM is required to perform
       additional NEPA analyses if a plan is amended or
       revised, see §§ 1610.5-5, 5-6).

542 U.S. at 73.

   [14] Emphasizing that an agency action is completed when
a land use plan is approved, BLM urges us to hold that
approval of the Roseburg and Medford resource management
plans in 1995, and the 2001 ROD amending them, are the rel-
evant federal actions for purposes of NEPA compliance. For
reasons discussed heretofore, however, BLM cannot sustain
the argument that the ASR Decisions were made pursuant to
a pre-approved and EIS-supported plan. On the contrary, the
decisions amended the management plans by adopting poli-
cies unequivocally rejected in previous agency actions and
scientific analyses. The Court’s holding in the last line of the
above-quoted passage is clear: when amending a resource
management plan—as defined in 43 C.F.R. § 1610.5-5—an
agency must perform supplemental NEPA analysis. Because
the ASR Decisions trigger the § 1610.5-5 requirements under
FLPMA, they also trigger the NEPA requirements under 40
C.F.R. § 1502.9(c)(1)(i).

  2.     “Significant New Circumstances or Information.”

   [15] The second prong of 40 C.F.R. § 1502.9(c)(1) requires
a NEPA analysis if there are “significant new circumstances
or information relevant to environmental concerns and bear-
ing on the proposed action or its impacts.” Id.; see also
SUWA, 542 U.S. at 72 (treating 40 C.F.R. § 1502.9(c)(1)(ii)
as an independent threshold that, if met, requires an agency to
conduct a NEPA analysis).

  [16] The ASR Decisions are clearly “relevant” to the envi-
ronment and have a “bearing” on BLM’s resource manage-
             KLAMATH SISKIYOU WILDLANDS v. BLM             18243
ment plans. The only inquiry is whether the ASR Decisions
are the product of “significant new circumstances or informa-
tion.” Given BLM’s decision to dramatically change the
vole’s Survey and Manage designation (especially in light of
the 2000 FSEIS’s unequivocal rejection of Alternative 2),
coupled with its argument that the ASR Decisions were based
on a pool of data 80% of which was not available when the
2000 FSEIS was created, the ASR Decisions and their impact
can be nothing short of “significant.”

   Moreover, our holding in Idaho Sporting Congress v.
Thomas, 137 F.3d 1146, 1150 (9th Cir. 1998) counsels in
favor of requiring NEPA analysis under circumstances such
as these. In Idaho Sporting, we recognized that under 42
U.S.C. § 4332(2) an EIS “must be prepared if substantial
questions are raised as to whether a project may cause signifi-
cant degradation of some human environmental factor.” 137
F.3d at 1149. We explained that “[t]he plaintiff need not show
that significant effects will in fact occur, but if the plaintiff
raises substantial questions whether a project may have a sig-
nificant effect, an EIS must be prepared.” Id. at 1150 (empha-
sis in original). This is a low standard. Given how
unequivocally the 2000 FSEIS rejected Alternative 2, adopt-
ing a policy within a matter of months of the 2000 FSEIS that
closely resembles the rejected alternative at least raises “sub-
stantial questions” regarding its impact.

   Furthermore, not only did BLM fail to conduct an EIS prior
to implementing either of the ASR Decisions, it did not even
conduct an EA. NEPA’s implementing regulations state that
EAs should be conducted “to provide sufficient evidence and
analysis for determining whether to prepare an environmental
impact statement or a finding of no significant impact.” 40
C.F.R. § 1508.9(a)(1). Indeed, as we explained in Metcalf v.
Daley, 214 F.3d 1135, 1143 (9th Cir. 2000), “[b]ecause the
very important decision whether to prepare an EIS is based
solely on the EA, the EA is fundamental to the decision-
making process.” In this vein, we have held that “[i]f the pro-
18244       KLAMATH SISKIYOU WILDLANDS v. BLM
posed action does not categorically require the preparation of
an EIS, the agency must prepare an EA to determine whether
the action will have a significant effect on the environment.”
Kern v. Bureau of Land Mgmt., 284 F.3d 1062, 1066 (9th Cir.
2002).

   [17] In sum, BLM is unable to explain (1) why the ASR
Decisions are not the product of “significant new circum-
stances or information,” (2) why there were not “substantial
questions regarding whether the ASR Decisions would have
a significant effect,” and (3) why it did not at least conduct
a environmental assessments to answer these questions. For
each of these reasons, BLM’s 2001 and 2003 ASR Decisions
regarding the red tree vole are invalid for failing to satisfy
NEPA.

  VI.   THE COW CATCHER AND COTTONSNAKE
                TIMBER SALES

   [18] Finally, because BLM’s 2001 and 2003 ASR Deci-
sions violated FLPMA and NEPA, we hold that the Cow
Catcher and Cottonsnake timber sales are invalid and must be
enjoined because they do not “conform to the approved
[resource management] plan[s].” 43 C.F.R. § 1610.5-3.

   The reasoning is straightforward. BLM did not conduct
pre-disturbance surveys for red tree voles in preparing either
the Cow Catcher or Cottonsnake timber sale. Under the Sur-
vey and Manage designations, Category C clearly requires
pre-disturbance surveys to be conducted at the habitat level
prior to habitat-disturbing activities. Because the 2001 and
2003 ASR Decisions are invalid and must be set aside, 5
U.S.C. § 706(2)(A), the Survey and Manage designations
under the 2001 ROD are reinstated. See Paulsen v. Daniels,
413 F.3d 999, 1008 (9th Cir. 2005) (“The effect of invalidat-
ing an agency rule is to reinstate the rule previously in
force.”). BLM did not comply with the resource management
plans and the 2001 ROD for either sale because it failed to
            KLAMATH SISKIYOU WILDLANDS v. BLM         18245
satisfy the Survey and Manage requirements pertaining to a
Category C species. Therefore, the sales may not go forward.

                      CONCLUSION

  For the foregoing reasons, we hold that the 2001 and 2003
ASR Decisions regarding the red tree vole are invalid under
both FLPMA and NEPA. We also conclude that the Cow
Catcher and Cottonsnake timber sales violate federal law
because they rely on the 2001 and 2003 ASR Decisions,
which we find to be unlawful.

  REVERSED.
