Wilderness Watch, Inc. v. U.S. Fish & Wildlife Service

FOR PUBLICATION
UNITED STATES COURT OF APPEALS
FOR THE NINTH CIRCUIT

WILDERNESS WATCH, INC.; ARIZONA 
WILDERNESS COALITION; SIERRA
CLUB; WESTERN WATERSHEDS
PROJECT; and GRAND CANYON
WILDLANDS COUNCIL, non-profit
corporations,
Plaintiffs-Appellants,
v.
U.S. FISH AND WILDLIFE SERVICE;
H. DALE HALL, in his official 
capacity as Director of the U.S.
Fish and Wildlife Service; PAUL
CORNES, in his official capacity as
the Kofa Wildlife Refuge
Manager; and CHRIS PEASE, in his
official capacity as Regional
Refuge Manager,
Defendants-Appellees,
and


20327
20328 WILDERNESS WATCH v. USFWS

U.S. SPORTSMEN’S ALLIANCE 
FOUNDATION; ARIZONA DESERT BIG
HORN SHEEP SOCIETY; ARIZONA
DEER ASSOCIATION; ARIZONA
ANTELOPE ASSOCIATION; No. 08-17406
FOUNDATION FOR NORTH AMERICAN D.C. No.
WILD SHEEP; YUMA VALLEY ROD &  2:07-cv-01185-
GUN CLUB, INC.; SAFARI CLUB MHM
INTERNATIONAL; SAFARI CLUB OPINION
INTERNATIONAL FOUNDATION;
NATIONAL RIFLE ASSOCIATION; and
STATE OF ARIZONA,
Defendant-Intervenors-Appellees.

Appeal from the United States District Court
for the District of Arizona
Mary H. Murguia, District Judge, Presiding

Argued and Submitted
December 10, 2009—San Francisco, California

Filed December 21, 2010

Before: A. Wallace Tashima, Susan P. Graber, and
Jay S. Bybee, Circuit Judges.

Opinion by Judge Graber;
Dissent by Judge Bybee
 WILDERNESS WATCH v. USFWS 20331

COUNSEL

Peter M.K. Frost, Western Environmental Law Center,
Eugene, Oregon, for the plaintiffs-appellants.

Justin R. Pidot, Environment & Natural Resources Division,
United States Department of Justice, Washington, D.C., for
the defendants-appellees.

James F. Odenkirk, Assistant Attorney General, Phoenix, Ari-
zona, and William P. Horn, Birch, Horton, Bittner and Cherot,
Washington, D.C., for the defendant-intervenors-appellees.

OPINION

GRABER, Circuit Judge:

The Kofa National Wildlife Refuge and Wilderness in
southwest Arizona contains a desert ecosystem that is home
to, among other species, bighorn sheep. After an unexpected
20332 WILDERNESS WATCH v. USFWS
decline in the population of the sheep, the United States Fish
and Wildlife Service (“Service”) built two water structures
(the Yaqui and McPherson tanks) within the wilderness area.
Plaintiffs Wilderness Watch, Inc., Arizona Wilderness Coali-
tion, Grand Canyon Wildlands Council, Western Watersheds
Project, and Grand Canyon Chapter of the Sierra Club
brought suit against the Service. Plaintiffs allege that the Ser-
vice’s actions violated the express prohibition on the develop-
ment of structures in the Wilderness Act, 16 U.S.C.
§§ 1131-1133. The district court granted summary judgment
to the Service, and Plaintiffs timely appeal. Reviewing de
novo, High Sierra Hikers Ass’n v. Blackwell, 390 F.3d 630,
638 (9th Cir. 2004), we reverse and remand.

FACTUAL AND PROCEDURAL HISTORY

Situated between two mountain ranges, the Kofa Refuge
and Wilderness consists of more than 600,000 acres of land
in the Sonoran Desert in southwest Arizona. The area contains
steep slopes, sparse vegetation, poor soil, and an extremely
dry ecosystem. Summer temperatures can reach 120 degrees.
The average rainfall measured at one weather station in the
Kofa Mountains is about seven inches a year. Most of the
rainfall occurs during one month, followed by many hot sum-
mer months with no measurable precipitation. The vegetation
is dominated by saguaro, creosote, ironwood, paloverde, and
mesquite. Kofa is home to 45 mammal species, including the
desert bighorn sheep and muledeer, and 47 species of reptiles.

President Franklin D. Roosevelt established the Kofa Game
Range by executive order in 1939. The President’s order
expressly designated the area for the “conservation and devel-
opment of natural wildlife resources,” Exec. Order No. 8039,
4 Fed. Reg. 438 (Jan. 25, 1939), and it was understood that
preservation of bighorn sheep was one of the principal rea-
sons for establishing the refuge. See David Brown, Early His-
tory, in THE DESERT BIGHORN SHEEP IN ARIZONA 5-7 (Raymond
M. Lee, ed., Ariz. Game & Fish Dep’t 1993). Following the
 WILDERNESS WATCH v. USFWS 20333
executive order, the Fish and Wildlife Service and the Bureau
of Land Management managed the land until 1976, when the
Service assumed sole jurisdiction and the reserve was
renamed the Kofa National Wildlife Refuge. See An Act to
amend the National Wildlife Refuge System Administration
Act of 1966, Pub. L. No. 94-223, 90 Stat. 199.

As a wildlife refuge, the area is subject to the provisions of
the Refuge Act. Among other things, the Refuge Act requires
the Secretary of the Interior to “provide for the conservation
of . . . wildlife,” “ensure that the biological integrity, diver-
sity, and environmental health of the System are maintained,”
and “assist in the maintenance of adequate water quantity and
water quality to fulfill the mission of the System and the pur-
poses of each refuge.” 16 U.S.C. § 668dd(a)(4)(A), (B), (F).
In 1990, Congress designated about 82% of the Kofa National
Wildlife Refuge as wilderness, and it became the Kofa
National Wildlife Refuge and Wilderness.1 Arizona Desert
Wilderness Act of 1990, Pub. L. No. 101-628, § 301(a)(3),
104 Stat. 4469. In doing so, Congress subjected the area to the
provisions of the Wilderness Act.

Under the Wilderness Act, the Service is “responsible for
preserving the wilderness character of the area,” but it also
must “administer such area for such other purposes for which
it may have been established as also to preserve its wilderness
character.” 16 U.S.C. § 1133(b). Congress specifically pro-
vided that “wilderness areas shall be devoted to the public
purposes of recreational, scenic, scientific, educational, con-
1
The record often fails to distinguish between the area designated as ref-
uge and the area designated as wilderness. We will refer to the area as the
Kofa Refuge or Kofa Wilderness as necessary in this opinion. When we
refer to the Kofa Wilderness, we are referring to the part of the Kofa Ref-
uge designated as wilderness, which is subject to provisions of the Wilder-
ness Act and the Refuge Act. We use Kofa Refuge to refer to the entire
area. We note that about 18% of the Kofa Refuge is subject only to the
provisions of the Refuge Act, an arguably less restrictive statute than the
Wilderness Act.
20334 WILDERNESS WATCH v. USFWS
servation, and historical use.” Id. “[E]xcept as necessary to
meet minimum requirements for the administration of the
area,” the Wilderness Act prohibits any “temporary road, . . .
use of motor vehicles, motorized equipment or motorboats,
. . . landing of aircraft, . . . mechanical transport, and . . .
structure or installation” within a wilderness area. Id.
§ 1133(c). The Act declares that the purposes of the Wilder-
ness Act are “within and supplemental to the purposes for
which . . . [the] national wildlife refuge systems are estab-
lished and administered.” Id. § 1133(a). Thus, in managing
the Kofa Wilderness, the Service must comply with both the
Wilderness Act and the Refuge Act.

Since the 1950s, the State of Arizona, non-profit organiza-
tions, and the federal government developed water sources
such as catchments, wells, and tanks to augment the availabil-
ity of water for the bighorn sheep that inhabit the area. There
are now more than 100 water sources in the area. During the
summer months, the distribution of bighorn sheep is restricted
by water availability, and most sheep can be found within a
two-mile radius of water sources. With the cooperation of the
Arizona Game and Fish Department and the Arizona Desert
Bighorn Sheep Society, refuge personnel build, maintain, and
monitor the water sources. During times of “extensive
drought,” refuge personnel transport water to the structures.
Wildlife managers believe that these water sources have been
instrumental in helping to restore the population of bighorn
sheep.

A. The Management Plan for the Refuge

After Congress designated most of the Kofa Refuge as a
wilderness area in 1990, and in an attempt to coordinate the
dual purposes of the Kofa Wilderness and Refuge, the Service
and the Bureau of Land Management (“BLM”) issued a man-
agement plan. Kofa National Wildlife Refuge and Wilderness
Interagency Management Plan (1997) (“Management Plan”).2
2
The plan also covered the New Water Mountains Wilderness.
 WILDERNESS WATCH v. USFWS 20335
The plan, which received public review and comment, was
intended to ensure that future management decisions and tech-
niques concerning the Kofa Wilderness were compatible with
the Wilderness and Refuge Acts. The plan recognized the pur-
pose of the Kofa Wilderness in preserving bighorn sheep:

Historically, Kofa . . . ha[s] played a central wild-
life and wildlands conservation role in western Ari-
zona. To counter dwindling populations of desert
bighorn sheep in the earlier part of the century, a
management theme relating to the recovery of the
species had become necessary beyond the establish-
ment of legal protection for the species under the
Arizona State Game code. Thus, a clear and domi-
nant strategy for the management of these histori-
cally “rocky, waterless sierras . . .” was designed
specifically for the recovery of bighorn sheep popu-
lations.

Management Plan at 2 (second ellipsis in original) (footnote
omitted). The plan stated that the Service and the BLM would
“continue important efforts on behalf of the bighorn sheep.”
Id. at 3. The plan acknowledged that, although the wilderness
designation of the land would “not chang[e] the purposes of
these areas or the importance of current activities,” the desig-
nation would “call for the consideration of these activities
within the larger ecological contexts and within national wil-
derness goals inherent in the Wilderness Act of 1964.” Id. The
plan stated that “[t]he needs of the species and the require-
ments of the Act are not necessarily in conflict. In fact, the
habitat management work done to benefit bighorn sheep,
including water development, could have a positive influence
on the natural cycles of predation and succession for a diver-
sity of life in the desert without detraction of wilderness attri-
butes and values.” Id. at 39-40.

After espousing a broad goal to reconcile the Wilderness
and Refuge Acts in the Kofa Wilderness, the plan discussed
20336 WILDERNESS WATCH v. USFWS
comprehensive planning objectives for the area. The plan
addressed many issues, including “protection of wilderness
values,” “wildlife and habitat management,” “law enforce-
ment and emergency services,” and “Native American reli-
gious access.” Id. at 5-7 (some capitalization omitted). With
respect to wildlife protection, the plan explained that “the Ser-
vice is responsible to carry out a dual, but nonetheless interre-
lated, role of managing for bighorn sheep within the context
of wilderness.” Id. at 37. According to the plan, the Service
would use “minimum tools” in order to “maintain[ ] an opti-
mal desert bighorn sheep population.” Id. at 53.

B. Decline in Population of Bighorn Sheep, and the
Service’s Response

As the Management Plan described, the Kofa Wilderness
historically has been home to the desert bighorn sheep. In
recent decades, the estimated population of the bighorn sheep
in the Kofa Wilderness and Refuge remained relatively stable,
with fluctuations between 600 and 800 sheep. Surveys done
in 1991 and 1997 (the period shortly after the refuge was first
designated as a wilderness area and while the Service was
preparing the Management Plan) revealed that the population
remained relatively stable at around 700 sheep, and the Ser-
vice determined that the carrying capacity of the area was
about 800 sheep. In 2000, the estimated population registered
on the high end of the range, at 813 sheep.

Due to the population’s stability, the Service and other gov-
ernment agencies have permitted certain activities that gener-
ally are viewed as inconsistent with population conservation.
For example, since 1979, the area has served as a primary
source of sheep for translocation programs to re-establish
populations of bighorn sheep in Arizona, Colorado, New
Mexico, and Texas. For decades, the Service translocated
sheep from the refuge on a nearly annual basis.3 The area also
3
The first translocation occurred in 1957, and a total of 569 sheep have
been moved from the refuge.
 WILDERNESS WATCH v. USFWS 20337
has been a hunting ground for bighorn sheep, and the Service
has issued a limited number of hunting licenses (between 9
and 17) each year. The Service also permits hiking in known
lambing areas, despite the sheep’s strong aversion to human
disturbance. One factor historically benefitting the bighorn
sheep within the Kofa Refuge was the absence of predators
such as mountain lions. Studies conducted in the 1990s found
no evidence of mountain-lion presence within the Kofa Ref-
uge.

In 2003, the estimated population of bighorn sheep in the
refuge was 623. Although this marked a decline since 2000,
the estimated population nevertheless remained comfortably
within the acceptable range of 600 to 800 sheep. Uncon-
cerned, the Service continued issuing hunting permits,
allowed hiking, and, encouraged by abundant rainfall in 2005,
translocated 31 sheep that year.

In 2006, however, surveys indicated that the population of
bighorn sheep had suffered an unexpected decline—to 390
sheep, or approximately 30% to 50% fewer sheep than in
recent decades. In response, the Service and the Arizona
Game and Fish Department prepared a document in 2007
titled “Investigative Report and Recommendations for the
Kofa Bighorn Sheep Herd” (“Investigative Report”). The
report came to no concrete conclusions concerning the recent
decline in population. Instead, the comprehensive document
examined the wide range of mortality factors of bighorn sheep
and, for each factor, it presented prescriptive strategies
intended to aid successful recovery of their population. The
most prominent factors identified by the report are availability
of water, predation, translocation, hunting, and human distur-
bance.

1. Availability of Water

The report identified availability of water as a “critical hab-
itat variable.” Investigative Report at 8. The report concluded
20338 WILDERNESS WATCH v. USFWS
that, “[i]n addition to a need for better monitoring and mainte-
nance of existing waterholes, a better distribution of perma-
nent water supplies is needed to provide water in all areas of
suitable sheep habitat.” Id. at 9. The report identified strate-
gies such as identifying existing permanent water sources that
could be improved by hauling water during low-water sea-
sons, identifying existing water sources that could be rede-
veloped to improve capacity and efficiency, and identifying
locations for new water sources. Id. at 10.

With respect to new water sources, the report stated that
“[n]ew water developments can likely be constructed outside
of wilderness, although construction in wilderness should
remain an option if a wilderness location best meets wildlife
management needs.” Id. at 9. “Plans for . . . new water devel-
opments will require an environmental assessment and mini-
mum requirement analysis/minimum tool analysis.” Id. at 10.

2. Predation

The report examined predation, primarily by mountain
lions. Id. at 11-15. The report noted that, until 2003, no moun-
tain lions were known to exist within the Refuge. Id. at 11-12.
Beginning in 2003, however, there have been mountain-lion
sightings and confirmed mountain-lion kills of bighorn sheep.
Id. at 12. “The overall impact of mountain lion predation on
the sheep population is unknown. It is unlikely that lion pre-
dation alone accounts for the decline observed, but it may be
additive to other sources of mortality or sufficient to prevent
sheep population recovery. Predation by bobcats or coyotes
may also be a contributing factor . . . .” Id. at 13. “Limited
removal of individual lions identified as regularly preying on
sheep may help the bighorn population recover to historical
levels.” Id. “Determining the cause of bighorn sheep mortality
is another vital part of assessing the effect of predation on the
Kofa population.” Id. The report recommended the strategies
of determining the extent of predation and reducing predation
 WILDERNESS WATCH v. USFWS 20339
by the removal of “offending” lions until the sheep population
fully recovers. Id. at 14-15.

3. Translocations

The report discussed the high demand by other natural
areas for translocated bighorn sheep and the history of trans-
locations from the Refuge to distant natural areas. Id. at
18-19. The report discussed the translocation of 31 sheep in
2005 despite the relatively low population estimate in 2003.
Id. at 18. The report found that, “[w]hile not the ultimate
cause of the population decline, the 2005 transplant may have
contributed to the low numbers seen in [one region of the Ref-
uge] on the 2006 survey.” Id. The report concluded that no
additional translocations will occur until the population of
sheep returns to historical levels. Id. at 18-19.

4. Hunting

“Hunting for desert bighorn sheep in Arizona is a once-in-
a-lifetime opportunity and the demand for bighorn sheep
hunting exceeds the allowable harvest.” Id. at 19. The report
described the very restrictive limits on permitted hunting and
the financial benefit to certain conservation groups, which are
granted a small number of annual permits for auction at fundr-
aisers. Id. The government agencies have “issued anywhere
from 5 to 17 bighorn sheep permits for the Kofa [Refuge] . . .
since 1960.” Id. The report recommended, without explana-
tion, that the agencies “[c]ontinue to offer bighorn sheep hunt-
ing opportunities consistent with sheep conservation.” Id. at
20.

5. Human Disturbance

“Bighorn sheep tend to use the highest, most rugged areas
within their home ranges for lambing.” Id. at 16. “Signal Peak
and Castle Dome Peak are two of the most distinctive features
of the refuge and as such are popular destinations for hikers.”
20340 WILDERNESS WATCH v. USFWS
Id. “Most use of these areas occurs in the cool winter months
(November-March), which strongly overlaps the peak lamb-
ing season of January-March.” Id. The report cited documen-
tation of “strong reactions (immediate running, left area and
did not return) from Kofa sheep in response to 1 or 2 people.”
Id. at 17. “Frequent human disturbance of ewes may cause
them to abandon these areas for less optimal habitat, which
could in turn affect lamb survival.” Id. The report recom-
mended “[r]educ[ing] the negative impacts of human recre-
ational activities on bighorn sheep” by monitoring sheep
usage during lambing season and, if necessary, closing popu-
lar hiking trails during lambing season. Id.

6. Conclusions and Additional Documents

The report contained no overall summary and came to no
conclusions about the causes of the decline in the population
of bighorn sheep, nor did it make a reasoned comparison
among the different potential causes and recovery strategies.
The report’s discussion of water does not mention the devel-
opment of the two water structures at issue in this case—the
Yaqui and McPherson tanks. Those structures are listed only
in a cost comparison chart near the end of the report. Id. at 23.
The report lists projects “in priority order”—though the rea-
sons for the priorities are unstated. Id. at 23 (capitalization
omitted). In that list, the development of the Yaqui and
McPherson tanks is listed sixth out of 14, below four strate-
gies aimed at monitoring mountain lions and reducing
mountain-lion predation and one overall strategy for recovery
of bighorn sheep. Id.

The Service prepared two other documents before initiating
work on the new water structures within the Kofa Wilderness.
The first document, titled “Kofa National Wildlife Refuge
Minimum Requirements Analysis,” is a two-page document
that contains a series of yes/no questions and requires the pre-
parer to circle, with a pen or pencil, either YES or NO. The
questions on the second page provide a very small space for
 WILDERNESS WATCH v. USFWS 20341
an explanation of a yes/no answer, but the first page contains
no such area. The preparer—whose identity is unknown—
dutifully circled answers to the questions and, on the second
page, provided very short explanations for the selected yes/no
answers to those questions. The final question asks if there are
potential adverse effects on wilderness. The preparer circled
“YES—PROCEED TO MINIMUM TOOL ANALYSIS.”

The second document, titled “Kofa National Wildlife Ref-
uge Minimum Tool Analysis,” is a detailed explanation of the
proposed action, an explanation for why it is necessary, alter-
native action plans (including the “no action” alternative), an
analysis of the effects of the alternative action plans, and a
summary description of the chosen alternative. In a section
titled “Why Project Is Necessary,” the Minimum Tool Analy-
sis states, in full:

Kofa NWR was established, in part, for the con-
servation of desert bighorn sheep and other wildlife,
and the maintenance of this population of desert big-
horn sheep is very important regionally for the con-
servation of sheep and as a source for transplants to
other locations in order to establish and re-establish
other sheep herds. Wildlife is an important compo-
nent of Wilderness.

The three alternatives are (1) no action, (2) constructing the
two structures with mechanized means, and (3) constructing
the two structures without mechanized means. The Service
selected alternative number 2: constructing the two structures
with mechanized means. The Service rejected the no-action
alternative because it would not help the sheep. The Service
rejected the alternative that used non-mechanized means
because it would increase the time needed to complete the
project, resulting in increased disturbance to wildlife and
human visitors alike.

Over a three-day period in 2007, the Service built the new
Yaqui and McPherson water structures, consisting mostly of
20342 WILDERNESS WATCH v. USFWS
aerated PVC pipe buried underground. Designed to catch
rainwater and run that water into small concrete weirs or
troughs, each system is capable of holding approximately
13,000 gallons of water. The Service decided to enter the two
areas with motorized vehicles and equipment because it con-
cluded, in its Minimum Tool Analysis, that using motorized
equipment was safer for the workers and would reduce the
amount of time the workers would be in the wilderness. The
workers used existing roads and removed tracks left by the
vehicles. The workers also covered the troughs with local
sand and rocks to blend the structures into the natural environ-
ment, so that only the troughs and small vent pipes are visible
above ground. The Yaqui tank is located in the refuge, just
outside the wilderness, but two or three water diversion weirs
fall within the wilderness. The McPherson tank is located well
inside the wilderness, but within 0.1 mile of a designated road
in the area.

C. The Current Suit

Plaintiffs filed suit against the Service shortly after the
completion of the Yaqui tank,4 arguing that the structure vio-
lated the Wilderness Act because the Act prohibits any “struc-
ture or installation” within a wilderness area “except as
necessary to meet minimum requirements for the administra-
tion of the area for the purpose of this chapter.” 16 U.S.C.
§ 1133(c). The district court granted summary judgment to the
Service, holding that the Service had not violated the Wilder-
ness Act.5 Plaintiffs timely appeal.
4
Plaintiffs also sought a temporary restraining order against construction
of the McPherson tank. The parties settled that issue out of court, and the
Service built the structure.
5
At the district court and on appeal, Plaintiffs also argued that the Ser-
vice violated the National Environmental Policy Act of 1969 by failing to
prepare a public analysis of the environmental effects of the water struc-
tures. Because we hold that Plaintiffs prevail on their claim under the Wil-
derness Act, we need not and do not reach their claim under the National
Environmental Policy Act.
 WILDERNESS WATCH v. USFWS 20343
DISCUSSION

[1] The Wilderness Act prohibits the development of
“structure[s] or installation[s]” on the land “except as neces-
sary to meet minimum requirements for the administration of
the area for the purpose of this chapter.” 16 U.S.C. § 1133(c).
Both parties (and we) agree that the two water tanks qualify
as structures or installations in the Kofa Wilderness. At issue
here is whether the water structures fall within the quoted
exception in the Act. The Service argues that these structures
fit within the exception in the Wilderness Act because (1) the
conservation of bighorn sheep is a valid “purpose” of the Wil-
derness Act and (2) the Service adequately determined that
the structures are necessary to meet the minimum require-
ments for conserving bighorn sheep. Plaintiffs disagree on
both points.

Under the Administrative Procedure Act, we may “set aside
agency action” only if we determine that the action was “arbi-
trary, capricious, an abuse of discretion, or otherwise not in
accordance with law.” 5 U.S.C. § 706(2)(a). We have held
that this standard requires us to

carefully review the record to ensure that agency
decisions are founded on a reasoned evaluation of
the relevant factors, and may not rubber-stamp
administrative decisions that [we] deem inconsistent
with a statutory mandate or that frustrate the con-
gressional policy underlying a statute. Nevertheless,
we may not substitute our judgment for that of the
agency . . . .

Friends of Yosemite Valley v. Norton, 348 F.3d 789, 793 (9th
Cir. 2003) (citation, internal quotation marks, and alterations
omitted).
20344 WILDERNESS WATCH v. USFWS
A. Conservation of Bighorn Sheep as a Purpose of the
Wilderness Act

As stated above, the Wilderness Act prohibits “structure[s]
or installation[s]” unless they are necessary to meet the mini-
mum requirements of a “purpose” of the Wilderness Act. 16
U.S.C. § 1133(c). We first must decide if the Service’s deter-
mination that a purpose of the Act includes conservation of
the bighorn sheep is unambiguously contrary to the language
of the Wilderness Act. If so, the structures violate the Act, and
we will “give effect to the unambiguously expressed intent of
Congress.” Chevron U.S.A. Inc. v. Natural Resources Def.
Council, Inc., 467 U.S. 837, 846 (1984). If not, we must then
determine what level of deference to grant to the Service’s
interpretation, a determination that depends upon whether the
Service’s interpretation has the force of law. Christensen v.
Harris County, 529 U.S. 576, 587 (2000).

[2] The Act begins with a broad statement of purpose:

In order to assure that an increasing population,
accompanied by expanding settlement and growing
mechanization, does not occupy and modify all areas
within the United States . . . , leaving no lands desig-
nated for preservation and protection in their natural
condition, it is hereby declared to be the policy of
the Congress to secure for the American people of
present and future generations the benefits of an
enduring resource of wilderness.

16 U.S.C. § 1131(a). The Act defines wilderness as “an area
where the earth and its community of life are untrammeled by
man, where man himself is a visitor who does not remain,”
and as “an area of undeveloped Federal land retaining its pri-
meval character and influence, . . . which is protected and
managed so as to preserve its natural conditions.” Id.
§ 1131(c). The Act also states that the “agency administering
any area designated as wilderness” must “administer such
 WILDERNESS WATCH v. USFWS 20345
area for such other purposes for which it may have been
established as also to preserve its wilderness character.” Id.
§ 1133(b). Had Congress stopped there, these strongly worded
phrases would have suggested that wilderness areas were to
remain untouched—not merely untouched by development
but, literally, untouched by humans. But Congress did not
mandate that the Service preserve the wilderness in a museum
diorama, one that we might observe only from a safe distance,
behind a brass railing and a thick glass window. Instead, Con-
gress stated that the wilderness was to be preserved as wilder-
ness and made accessible to people, “devoted to the public
purposes of recreational, scenic, scientific, educational, con-
servation, and historical use.” Id. Congress was specific about
what it understood might be necessary to preserve the wilder-
ness for such public purposes. Congress expressly authorized
structures, motorized vehicles, and temporary roads if such
things are necessary to meet the minimum requirements for
administering the area, id. § 1133(c); indeed, the Act permits,
under certain circumstances, aircraft and motorboat use and
even mining, id. § 1133(d). Those uses are incompatible with
a museum notion of wilderness.

[3] Read as a whole, the Act gives conflicting policy direc-
tives to the Service in administering the area. The Service is
“charged with maintaining the wilderness character of the
land, providing opportunities for wilderness recreation, man-
aging fire and insect risk, and even facilitating mineral extrac-
tion activities.” High Sierra, 390 F.3d at 647. It is charged
with simultaneously devoting the land to “conservation” and
protecting and preserving the wilderness in its natural condi-
tion. 16 U.S.C. §§ 1131(c), 1133(b). We cannot discern an
unambiguous instruction to the Service. Rather, those compet-
ing instructions call for the application of judgment and dis-
cretion. We may be able to identify violations at the margins
but, in this case, the Act is not so clear that we can identify
precisely what the Service must do and must not do. We con-
clude that the purpose of the Wilderness Act with regard to
conservation is ambiguous. See High Sierra, 390 F.3d at
20346 WILDERNESS WATCH v. USFWS
647-48 (“Although we believe that Congress intended to
enshrine the long-term preservation of wilderness areas as the
ultimate goal of the Act, the diverse, and sometimes conflict-
ing list of responsibilities imposed on administering agencies
renders Congress’s intent arguably ambiguous.”).

Our decision in Wilderness Society v. United States Fish &
Wildlife Service, 353 F.3d 1051 (9th Cir. 2003) (en banc), is
not to the contrary. In Wilderness Society, the Service initi-
ated a sockeye salmon enhancement project in a freshwater
lake, located in the Kenai Wildlife Refuge and Wilderness,
that flowed into the Gulf of Alaska. The Service planned to
allow a private corporation to capture 10,000 sockeye salmon
each year and transport about 10 million eggs to a hatchery
outside the Kenai Wilderness. During the spring, the organi-
zation planned to return about 6 million salmon to the wilder-
ness and to sell the rest. Id. at 1058. The plaintiffs argued that
the corporation’s activities fell within the Wilderness Act’s
ban on all “commercial enterprise[s]” within a wilderness area
(subject to certain exceptions inapplicable in that case). Id. at
1061 (citing 16 U.S.C. § 1133(c)). Looking to the common
meaning of the term and to the purpose and structure of the
Act, we held that the corporation’s activities unambiguously
fell within the Act’s prohibition on commercial enterprises.6
Id. at 1062.

Wilderness Society is easily distinguishable from the pres-
ent case. There, we gave effect to the unambiguously
expressed intent that, subject to certain inapplicable excep-
tions, commercial enterprises were prohibited. The Service
argued that its interpretation of the undefined term “commer-
cial enterprise” was entitled to some deference but we held
that, because the primary purpose and effect of the action was
6
In the alternative, we held that the corporation’s activities constituted
a commercial enterprise, “even if we were to assume that the Wilderness
Act’s prohibition on commercial enterprise within the wilderness is
ambiguous.” Wilderness Soc’y, 353 F.3d at 1067-69.
 WILDERNESS WATCH v. USFWS 20347
purely commercial, no deference was due. Here, by contrast,
we must analyze conflicting instructions in the Wilderness
Act: The Service must preserve the wilderness character of
the area while at the same time providing for “recreational,
scenic, scientific, educational, conservation, and historical
use.” 16 U.S.C. § 1133(b). Both the specific statutory man-
date that “conservation” is a valid purpose of the Act and the
historical focus of the area on the preservation of bighorn
sheep render this case vastly different from the situation we
analyzed in Wilderness Society.

Because we conclude that the term “conservation” is
ambiguous, we turn to the question of what level of deference
to grant the Service’s interpretation of “conservation” as
including wildlife conservation and, more specifically, con-
servation of bighorn sheep. United States v. Mead Corp., 533
U.S. 218, 229-30 (2001); Christensen, 529 U.S. at 587. We
apply Chevron deference “when it appears that Congress dele-
gated authority to the agency generally to make rules carrying
the force of law, and that the agency interpretation claiming
deference was promulgated in the exercise of that authority.”
Mead, 533 U.S. at 226-27. “It is fair to assume generally that
Congress contemplates administrative action with the effect
of law when it provides for a relatively formal administrative
procedure tending to foster the fairness and deliberation that
should underlie a pronouncement of such force.” Id. at 230.
By contrast, “[i]nterpretations such as those in opinion letters
—like interpretations contained in policy statements, agency
manuals, and enforcement guidelines, all of which lack the
force of law—do not warrant Chevron-style deference.”
Christensen, 529 U.S. at 587. “Such views, . . . even if not
authoritative for purposes of Chevron, are entitled to so-called
Skidmore deference insofar as they ‘constitute a body of expe-
rience and informed judgment to which courts and litigants
may properly resort for guidance.’ ” Vigil v. Leavitt, 381 F.3d
826, 835 (9th Cir. 2004) (quoting Skidmore v. Swift & Co.,
323 U.S. 134, 140 (1944)).
20348 WILDERNESS WATCH v. USFWS
[4] Here, the 1997 Management Plan was subject to public
review and comment and was intended to “provide long-term
management guidance.” But, other than stating that the plan
was subject to public review and comment, the record is
bereft of any other information describing the formality of the
administrative procedure that fostered the plan. We are not
convinced that the “management guidance” included in the
plan carries the force of law. On this record, we are unable to
distinguish with certainty the plan from “interpretations con-
tained in policy statements, agency manuals, and enforcement
guidelines, all of which lack the force of law.” Christensen,
529 U.S. at 587. We therefore apply Skidmore deference.
Under that standard, “the deference to be accorded . . .
depends upon ‘the thoroughness evident in its consideration,
the validity of its reasoning, its consistency with earlier and
later pronouncements, and all those factors which give it
power to persuade, if lacking power to control.’ ” Wilderness
Soc’y, 353 F.3d at 1060 (quoting Mead, 533 U.S. at 228).

[5] The plan demonstrated consistency in recounting the
history of Kofa and its “conservation role in western Arizo-
na.” Management Plan at 2. Preservation of the bighorn sheep
in the area was one of the principal motivations for President
Roosevelt’s establishing the Kofa Game Range in 1939. From
the beginning, federal agencies cooperated with the Arizona
Game and Fish Department to protect the bighorn sheep.7 The
plan reiterated that preserving desert bighorn sheep was an
important component of the management of the area and
noted that the “management theme” of the area is devoted
“[t]o counter dwindling populations of desert bighorn sheep”
and to “continue important efforts on behalf of the bighorn
sheep.” Id. at 2-3.

[6] The plan also demonstrated thoroughness in addressing
the new requirements that the wilderness designation would
impose on the goal of conserving bighorn sheep. It concluded:
7
Arizona granted legal protection to bighorn sheep in 1913.
 WILDERNESS WATCH v. USFWS 20349
There is no question that management of this spe-
cies remains as one of the princip[al] missions of the
Kofa [National Wildlife Refuge] . . . . However, the
new considerations relative to the Wilderness desig-
nations require the Service and the BLM to review
management techniques and their compatibility with
wilderness principles.

Id. at 36. The plan acknowledged that “the Service is respon-
sible to carry out a dual, but nonetheless interrelated, role of
managing for bighorn sheep within the context of wilder-
ness.” Id. at 37. The plan further recognized that the Service
had “to maintain the natural character of the landscape” con-
sistent with the Wilderness Act, a duty that required use of
“the minimum tool necessary to accomplish the work” and
“technologies . . . as unobtrusive as possible.” Id. at 37, 39.
The plan continued:

The needs of the species and the requirements of the
Act are not necessarily in conflict. In fact, the habitat
management work done to benefit bighorn sheep,
including water development, could have a positive
influence on the natural cycles of predation and suc-
cession for a diversity of life in the desert without
detraction of wilderness attributes and values.

Id. at 39-40.

[7] In light of the historical purpose of the area to preserve
bighorn sheep and the explicit purpose of “conservation” in
the Act, we find that the Service’s reasoning was thorough,
valid, consistent, and persuasive. We defer to the Service’s
interpretation in the Management Plan that conservation of
the bighorn sheep is consistent with the purposes of the Wil-
derness Act.
20350 WILDERNESS WATCH v. USFWS
B. The Wilderness Act’s Exception for Structures that are
“Necessary” to Meet the “Minimum Requirements” for
Conserving Bighorn Sheep

[8] The Wilderness Act prohibits the development of any
structure within a wilderness area, subject to only one excep-
tion: “except as necessary to meet minimum requirements for
the administration of the area for the purpose of this chapter.”
16 U.S.C. § 1133(c). Because the conservation of bighorn
sheep is a valid purpose of the Wilderness Act, the relevant
question is whether the Service made an adequately reasoned
determination of necessity. See High Sierra, 390 F.3d at
646-47 (holding that, in order to invoke an exception to pro-
hibited conduct in a wilderness area, the Wilderness Act
requires the relevant agency to make a reasoned finding of
necessity).

In High Sierra, we interpreted the similar provision 16
U.S.C. § 1133(d)(5), which permits commercial services “to
the extent necessary for activities which are proper for realiz-
ing the recreational or other wilderness purposes of the areas.”
We held that “[i]t is clear that the statutory scheme requires
. . . that the Forest Service make a finding of ‘necessity’
before authorizing commercial services in wilderness areas.”
High Sierra, 390 F.3d at 646. We held that the Wilderness
Act “does not specify any particular form or content for such
an assessment” and that we must defer to the form selected by
the agency. Id. at 646-47. Accordingly, we found that a
“Needs Assessment” document prepared by the Forest Ser-
vice sufficed as the required “necessity” finding. Id. at 647.

However, under the terms of the Wilderness Act,
a finding of necessity is a necessary, but not suffi-
cient, ground for permitting commercial activity in a
wilderness area. The finding of necessity required by
the Act is a specialized one. The Forest Service may
authorize commercial services only “to the extent
necessary.”
 WILDERNESS WATCH v. USFWS 20351
Id. (quoting 16 U.S.C. § 1133(d)(5)). Keying off the empha-
sized text, we held that “the Forest Service must show that the
number of [commercial activity] permits granted was no more
than was necessary to achieve the goals of the Act.” Id.

We held that the Needs Assessment document did not meet
that requirement because “[n]owhere in the [document] does
the Forest Service articulate why the extent of such [commer-
cial] services authorized by the permits is ‘necessary.’ ” Id.
The Needs Assessment document “examined independently
three topics related to the need for commercial services: the
types of activities for which commercial services are needed,
the extent to which current permits are being used, and the
amount of use the land can tolerate.” Id. “All of these are rele-
vant factors to consider . . . [but], at some point in the analy-
sis, the factors must be considered in relation to one another.”
Id. “If complying with the Wilderness Act on one factor will
impede progress toward goals on another factor, the adminis-
tering agency must determine the most important value and
make its decision to protect that value. That is what the Forest
Service failed to do in this case.” Id.

[9] Here, similarly, the relevant statutory provision prohib-
its the creation of structures within a wilderness area “except
as necessary to meet minimum requirements for the adminis-
tration of the area for the purpose of this chapter.” 16 U.S.C.
§ 1133(c). Like the similar provision in High Sierra, this pro-
vision requires the agency to make a finding of necessity. But
a generic finding of necessity does not suffice, High Sierra,
390 F.3d at 647; the Service must make a finding that the
structures are “necessary” to meet the “minimum requirements
for the administration of the area for the purpose of [conserv-
ing bighorn sheep],” 16 U.S.C. § 1133(c) (emphasis added).8
8
It is that specific necessity finding, mandated by the statute, that the
Service must make. We in no way hold that the Service must make a find-
ing of “absolute necessity.” Dissent at 20376.
20352 WILDERNESS WATCH v. USFWS
[10] The Service failed to make that required finding. The
Service undoubtedly found that, assuming that improvements
to water facilities were necessary, the development of the two
water structures was necessary. The record contains the requi-
site necessity finding as to that narrow question and a rea-
soned analysis justifying the finding. But the key question—
whether water structures were necessary at all—remains
entirely unanswered and unexplained by the record, even
though the Service’s own documentation strongly suggests
that many other strategies could have met the goal of conserv-
ing bighorn sheep without having to construct additional
structures within the wilderness area (for example, eliminat-
ing hunting, stopping translocations of sheep, and ending pre-
dation by mountain lions).

The Service points us to the three documents discussed in
some detail in the factual background section, above: the 2007
Investigative Report, the Minimum Requirements Analysis,
and the Minimum Tool Analysis. But they do not contain the
required analysis.

The Service’s 2007 Investigative Report provided a thor-
ough, neutral, and scientific assessment of the many factors
that contribute to sheep mortality, and the report made recom-
mendations pertaining to each mortality factor. But the Inves-
tigative Report did not—and did not purport to—assess the
factors relative to each other. Nor did the Investigative Report
reach legal conclusions or even cite the relevant legal stan-
dard that the Service must apply before developing structures
in a wilderness area. What the report did conclude, however,
is that many factors other than access to water, either alone or
in combination, might suffice to restore the population of big-
horn sheep.

Perhaps most importantly, the report concludes that moun-
tain lions recently began inhabiting the Kofa Refuge and kill-
ing bighorn sheep; in fact, the arrival of mountain lions
corresponds precisely to the time frame in which the popula-
 WILDERNESS WATCH v. USFWS 20353
tion of sheep declined from its previously stable, optimal
level. After decades of mountain-lion absence, the Service
first received reports of mountain lions (and mountain-lion
kills of bighorn sheep) in the Kofa Refuge during the crucial
time period of 2003 to 2006. The report even concludes that
mountain-lion predation may be “sufficient to prevent sheep
population recovery.” In its summary chart, the report lists
four different actions related to mountain-lion predation as
higher priorities than the development of water structures.

Similarly, the report acknowledges that, despite the rela-
tively low population of sheep in 2003, the Service carried out
a translocation of 31 sheep from the Refuge in 2005 which,
the report concluded, “may have contributed to the low num-
bers seen in [one region of the Refuge] on the 2006 survey.”
The report recommends that the temporary cessation of trans-
locations be continued.

Next, the report notes the obvious fact that hunting results
in a population decline. Yet the report recommends, without
explanation, that hunting be continued in the Refuge.

Finally, the report explains that human disturbance may
lead to a reduction in the survival rate of bighorn lambs, and
the report notes that peak hiking season in prime lambing ter-
ritory corresponds directly to peak lambing season. The report
concludes that temporary trail closures may be advisable.

[11] In short, the report identified many different actions
that were likely to lead to an increase in the population of big-
horn sheep: reduction in mountain-lion predation, cessation of
translocations, moratorium on hunting, and temporary trail
closures. Importantly, in contrast to the creation of new struc-
tures within the wilderness, the Wilderness Act does not pro-
hibit any of those actions. The Service could have taken any
or all of those actions without the need for a finding of neces-
sity. Yet nowhere in the record does the Service explain why
20354 WILDERNESS WATCH v. USFWS
those actions, alone or in combination, are insufficient to
restore the population of bighorn sheep.

The Investigative Report did, of course, identify the cre-
ation of the new structures as one possible strategy toward the
recovery of the bighorn sheep population. But the report never
stated that the two water structures are necessary, either in the
abstract or with respect to the statutory standard (which the
report nowhere cited). The report simply listed that action-
item alongside the many other action-items, including those
described above, all of which might contribute to the recovery
of the bighorn sheep. Indeed, the report concluded that “[n]ew
water developments can likely be constructed outside of wil-
derness,” which would not require a finding of necessity. To
the extent that the report contemplated the construction of
water structures within the wilderness, it stated that those
structures “will require . . . [a] minimum requirement analy-
sis/minimum tool analysis.”

Before building the two water structures, the Service did
complete a Minimum Requirements Analysis and a Minimum
Tool Analysis. Those documents amply describe the reasons
for the Service’s decision to construct these two particular
water structures, assuming that water structures are necessary
at all. But, again, nowhere does the Service address that
underlying assumption. The documents leap from the worthy
goal of conserving bighorn sheep to the need for additional
water structures. The basis for that analytical leap is nowhere
described.

In fact, with only one possible exception, the two docu-
ments provide no basis for the conclusion that the Service
even considered the possibility of actions other than the con-
struction of water structures. The documents as a whole dem-
onstrate that the Service began with the assumption that water
structures are necessary and reasoned from that starting point.

In only one place is it even arguable that the Service con-
sidered the possibility of other actions. On the first page of the
 WILDERNESS WATCH v. USFWS 20355
yes/no checklist, the Service circled “NO” in response to the
question: “Are there other less intrusive actions that can be
taken or that should be tried first inside or outside wilderness
that will resolve this issue? (i.e. signing, visitor education,
information, regulations, use limits, law enforcement, are [sic]
or trail closures, etc). Circle Yes or No.” Viewing the docu-
ments as a whole, the Service’s response to this question
likely carried forward its primary underlying assumption: that
water structures are necessary. In context, the Service likely
interpreted this question as asking whether “other less intru-
sive [water-based] actions” such as hauling of water or devel-
opment of structures outside of wilderness “should be tried
first.”

Even if one assumes that the Service understood this ques-
tion as querying whether other non-water-based actions
should be tried first, this lone, generic question cannot meet
the requirement under the Wilderness Act that the Service
explain its conclusion. As we wrote in High Sierra, 390 F.3d
at 647, the Service must, “at some point in the analysis,”
weigh the relevant factors “in relation to one another.”
(Emphasis added.) As in High Sierra, “[n]owhere in the
[record] does the . . . Service articulate why” the action taken
is “necessary” to meet the “minimum requirements” of the
Act. Id. (emphasis added). And, as in High Sierra, that failure
is fatal. Where, as here, the record demonstrates that many
alternative actions not prohibited by the Wilderness Act very
well could have attained the Service’s goal, a single yes/no
question cannot suffice to invoke the very limited exception
for structures that are necessary to meet the minimum require-
ments for the administration of the purposes of the Wilderness
Act. The Service’s decision “entirely fail[s] to consider an
important aspect of the problem,” namely, the failure to con-
sider whether new water structures are necessary at all. Lands
Council v. McNair, 537 F.3d 981, 987 (9th Cir. 2008) (en
banc) (internal quotation marks omitted), overruled in other
part as recognized by Am. Trucking Ass’ns v. City of Los
Angeles, 559 F.3d 1046, 1052 (9th Cir. 2009).
20356 WILDERNESS WATCH v. USFWS
[12] The Wilderness Act imposes a strong prohibition on
the creation of structures, subject only to an exception for
structures that are necessary to meet the Act’s minimum
requirements. Just because a particular variable affects the
sheep’s viability, the Service is not free to create structures
addressing that variable without regard to any other variables
at play. The Act certainly provides for some flexibility to
address a given situation, even with imperfect information
and time and budget constraints. But, unless the Act’s “mini-
mum requirements” provision is empty, the Service must, at
the very least, explain why addressing one variable is more
important than addressing the other variables and must
explain why addressing that one variable is even necessary at
all, given that addressing the others could fix the problem just
as well or better.

[13] There is little question that improvements to the water
supply likely will help the sheep recover. But, when the issue
is a new structure, that conclusion is not good enough under
this statute. The statute requires that a structure be “necessary
to meet minimum requirements” of the wilderness. 16 U.S.C.
§ 1133(c). It is beyond dispute that, if addressing other vari-
ables will lead to satisfactory sheep recovery, then a new
structure is not “necessary.” The Service’s complete failure to
address that key question is fatal to its conclusion.9

CONCLUSION

[14] The Wilderness Act requires a delicate balancing
between Congress’ desire to maintain lands untouched by
humans and Congress’ recognition that such an idealistic view
9
As we have explained, and notwithstanding the dissent’s assertions to
the contrary, the documents in the record simply do not contain an expla-
nation for that key question. The dissent cobbles together its own explana-
tion from disparate parts of the various documents at issue and from its
own analysis of sheep recovery, but it is the Service’s explanation, or lack
thereof, that we must review, and we cannot supply missing elements for
the agency.
 WILDERNESS WATCH v. USFWS 20357
is subject to some practical limitations. The prohibition on the
creation of permanent structures within a wilderness area is
one of the strictest prohibitions, subject only to an exception
for structures that are necessary to meet the minimum require-
ments for the administration of the purposes of the Act. It may
be that the two water structures at issue here are, in fact, nec-
essary to meet the minimum requirements for conserving big-
horn sheep, which is a permissible purpose. But, in light of
the many other potential avenues of achieving bighorn sheep
conservation identified by the Service itself, the Service must
provide enough evidence and explanation in the record to
assure this court that it fully considered those avenues and
nevertheless rationally concluded that new water structures
are, in fact, necessary. Because the record is wholly inade-
quate to meet that requirement, we reverse the district court’s
determination to the contrary and remand with instructions to
determine the appropriate remedy. On remand, the court may
accept briefing from the parties on whether to require the Ser-
vice to dismantle the structures, to remand the matter to the
Service for reconsideration regarding “necessity” under the
Wilderness Act, or to fashion such other relief as may be appro-
priate.10

REVERSED and REMANDED with instructions.

10
On appeal, Plaintiffs requested a specific remedy: removal of the
structures via non-motorized means. The Service did not object and,
indeed, did not address the issue of remedy at all. We express no opinion
on whether the Service may be precluded, by waiver or otherwise, from
objecting to that form of relief.
Because the Service did not brief the issue of remedy, we believe that
it is prudent to remand the issue to the district court to address with the
benefit of full advocacy. The dissent’s view of the appropriate remedy is,
as we state in text, one possible option. But we are perplexed by the dis-
sent’s insistence that we must reach an issue that one party failed to brief
—particularly because our decision to remand prejudices neither party.
20358 WILDERNESS WATCH v. USFWS
BYBEE, Circuit Judge, dissenting:

This should not have been a hard case. For more than sev-
enty years, “[t]he dominant wildlife and habitat management
theme for the Kofa . . . has been the preservation of the desert
bighorn sheep species.”1 For much of that period, the Fish and
Wildlife Service (“Service”), together with the BLM and the
Arizona Game and Fish Department (“AGFD”), has supplied
water to bighorn herds in the Kofa. So it is no surprise that
after observing a dramatic decline in the bighorn population
in this region, the Service proposed a variety of non-mutually
exclusive solutions, including redevelopment of the Yaqui
and McPherson tanks—two existing but unreliable water
sources considered to be critical to the survival of the bighorn
in the Eastern Kofa.

Although “[t]here is little question that improvements to the
water supply likely will help the sheep recover,” Maj. Op. at
20356, and although “[t]he Service undoubtedly found that
. . . the development of the two water structures was neces-
sary,” id. at 20352, and although the documents prepared by
the Service “amply describe the reasons for the Service’s
decision to construct these two particular water structures,” id.
at 20354, the majority nevertheless holds that the agency
acted arbitrarily and capriciously because it never explained
whether there was a “need for additional water structures,”
id., or even “whether water structures were necessary at all.”
Id. at 20352. In the process, the majority holds that the Ser-
vice should have engaged in a formalized, side-by-side com-
parative analysis of the various factors affecting the bighorn’s
decline, id. at 20354, even though we previously told the Ser-
vice that the Wilderness Act “does not specify any particular
form or content” for a finding that an action is “necessary.”
1
U.S. FISH & WILDLIFE SERVICE, KOFA NATIONAL WILDLIFE REFUGE AND
WILDERNESS AND NEW WATER MOUNTAINS WILDERNESS INTERAGENCY PLAN,
ENVIRONMENTAL ASSESSMENT, AND DECISION RECORD 35 (1996) [hereinafter
Kofa Management Plan].
 WILDERNESS WATCH v. USFWS 20359
High Sierra Hikers Ass’n. v. Blackwell, 390 F.3d 630, 647
(9th Cir. 2004). In so holding, as I explain in Part I, the major-
ity ignores our deferential standard of review under the APA
and engrafts new procedural requirements onto the Wilder-
ness Act.

Additionally, as I explain in Part II, the majority fundamen-
tally misconstrues the appropriate remedy for cases where an
agency provides insufficient reasons for its action. Rather
than remanding this case to the agency for a fuller explanation
of its reasoning—as both Supreme Court and circuit precedent
require—the majority remands to the district court for an
exercise in futility: determination of the appropriate remedy.
Then, under the guise of “express[ing] no opinion on whether
the Service may be precluded, by waiver or otherwise, from
objecting to th[e] form of relief” requested by the Plaintiffs,
the majority even suggests that dismantling the structures may
be the only appropriate remedy in this case. Maj. Op. at 20357
n.10.

I respectfully dissent.

I

There is nothing unusually difficult about this case. Like
any other routine administrative law appeal, it presents a find-
ing made by an agency—here, the Service’s finding that
building additional water sources was necessary to meet mini-
mum administrative requirements for the conservation of the
bighorn in the Kofa—and a subsequent decision based upon
this finding—here, the Service’s decision to redevelop the
Yaqui and McPherson tanks. Our task is, simply, to determine
whether the agency’s finding, and thus its subsequent deci-
sion, was “arbitrary” or “capricious,” 5 U.S.C. § 706(2)(A), in
light of the administrative record as a whole.

We know the standard of review: We may not overturn the
Service’s decision simply because we disagree with it, nor
20360 WILDERNESS WATCH v. USFWS
may we substitute our own judgment for that of the Service
because we feel the Service’s decision was imprudent or
unwise. See River Runners for Wilderness v. Martin, 593 F.3d
1064, 1070 (9th Cir. 2010). Rather, we must simply determine
whether “the [Service’s] decision is founded on a rational
connection between the facts found and the choices made . . .
and whether [the Service] has committed a clear error of judg-
ment.” Id. (citation and quotation marks omitted). “To do so,
we look to the evidence the . . . Service has provided to sup-
port its conclusions, along with other materials in the record,
to ensure that the Service has not, for instance, relied on fac-
tors which Congress has not intended it to consider, entirely
failed to consider an important aspect of the problem, offered
an explanation for its decision that runs counter to the evi-
dence before the agency, or an explanation that is so implausi-
ble that it could not be ascribed to a difference in view or the
product of agency expertise.” The Lands Council v. McNair,
537 F.3d 981, 993 (9th Cir. 2008) (en banc) (quotation marks
and alterations omitted). “Even when [the Service] explains
its decision with less than ideal clarity, [we] will not upset the
decision on that account if the [Service’s] path may reason-
ably be discerned.” Alaska Dept. of Envtl. Conservation v.
EPA, 540 U.S. 461, 497 (2004) (quotation marks and citation
omitted).

Here, the Service has produced three primary documents to
explain why redeveloping the Yaqui and McPherson water
structures was necessary to meet minimum requirements for
the conservation of the bighorn: (1) the Investigative Report
and Recommendations for the Kofa Bighorn Sheep Herd
(“Kofa Bighorn Investigative Report”), a 39-page report that
found a need to supply bighorn sheep with water; (2) the Kofa
National Wildlife Refuge Minimum Tool Analysis (“Kofa
Minimum Tool Analysis”), a six-page document that con-
cluded that without action, the bighorn population would con-
tinue to decline; and (3) the Kofa National Wildlife Refuge
Minimum Requirements Analysis (“Kofa Minimum Require-
ments Analysis”), a two-page decision document that found
 WILDERNESS WATCH v. USFWS 20361
there were no other less intrusive actions that could be taken
to reverse the decline of the bighorn.2 Together, these docu-
ments demonstrate that the Service considered all the impor-
tant aspects of the problem and offered a reasonable
explanation for the necessity of building additional water
sources for the sheep. Accordingly, with a few citations to
important sections of these various reports, the majority
should uphold the Service’s decision in a rather unremarkable
opinion. Instead, the majority holds the Service’s decision
arbitrary and capricious not because of what the Service said
in its reports, but because of what, allegedly, it did not say.
Specifically, the majority claims the Service never stated that
water structures were necessary and never explained why
addressing factors other than water would be insufficient to
reverse the bighorn’s decline. As I discuss below, the record
reveals the Service thoroughly addressed the majority’s con-
cerns.

A

First, the majority holds the Service acted arbitrarily and
capriciously because the Service “never stated that the two
water structures are necessary, either in the abstract or with
respect to the statutory standard.” Maj. Op. at 20354. How-
ever, the Service did explicitly state “there [are no] other less
intrusive actions,” other than redeveloping the two water
tanks, that would help the sheep recover. See Kofa Minimum
2
The Service has also discussed the bighorn in more comprehensive
studies, such as the 1996 Kofa Management Plan, a more than 100-page
management plan that considered, among other things, how the Service
could “carry out a dual, but nonetheless interrelated, role of managing for
bighorn sheep within the context of wilderness.” Kofa Management Plan
at 37. See 16 U.S.C. § 1133(a) (The Wilderness Act is “within and supple-
mental to the purposes for which . . . units of the . . . natural wildlife ref-
uge systems are established and administered.”) (emphasis added).
Additionally, the Service described its proposed redevelopment of the two
tanks in a five-page document, Categorical Exclusion, Yaqui and McPher-
son Tanks Redevelopment Projects (“Kofa Categorical Exclusion”).
20362 WILDERNESS WATCH v. USFWS
Requirements Analysis at 1. I give this statement its plain and
ordinary meaning: “the two water structures are necessary,
either in the abstract or with respect to the statutory standard.”
Maj. Op. at 20354. To explain the Service’s statement, the
majority conjures up a handy expedient: the Service’s state-
ment is meaningless because, you see, the Service had already
“assum[ed] that water structures are necessary and reasoned
from that starting point.” Id. at 20354. Thus, according to the
majority, the Service’s statement “likely carried forward [this]
primary underlying assumption.” Id. As I explain below, a
close reading of the Service’s reports reveals the Service
never assumed water structures were necessary; rather, the
Service arrived at this conclusion after carefully studying the
bighorn’s decline.

The Kofa Bighorn Investigative Report, conducted jointly
by the Service and the AGFD, reveals both that bighorn sheep
need reliable water sources to survive and that reliable water
sources must be supplied to the bighorn. Specifically, the
report found that “water distribution is a critical habitat vari-
able for desert bighorn” and that the sheep are “dependen[t]
on reliable water sources.” Kofa Bighorn Investigative Report
at 8. The report found that in areas where the AGFD had
maintained water for the sheep, the populations “remained
fairly stable in comparison to the Kofa population.” Id. at 9.
Yet despite the critical importance of reliable water sources,
“[f]ew of the [existing] bighorn waters could be considered
permanent, which means that they may go dry during the
height of summer when water is needed most, or during
drought years.” Id. Indeed, a water survey conducted during
a drought year revealed that “very few of the known
waterholes were not dry.” Id. This observation is significant
first, because it shows sheep must be supplied with water, and
second, because when “a water source dries up, bighorn may
not move to new areas to find water.” Id. Thus, it does not
matter much that the Kofa Wilderness “has a large number of
water sources” because “their utility for sheep and their reli-
 WILDERNESS WATCH v. USFWS 20363
ability varies greatly.” Id. In light of these observations, the
report determined that

[i]n addition to a need for better monitoring and
maintenance of existing waterholes, a better distribu-
tion of permanent water supplies is needed to pro-
vide water in all areas of suitable sheep habitat. . . .
Some existing ephemeral waters can be improved or
redeveloped to hold water longer, but in some areas
new waters might need to be built. . . . New water
developments can likely be constructed outside of
wilderness, although construction in wilderness
should remain an option if a wilderness location best
meets wildlife management needs.

Id. Accordingly, the report recommended that the agency
“[i]dentify existing waters that need to be redeveloped to
improve water holding capacity and efficiency” to “[e]nsure
year-round water availability for all bighorn sheep on the
Kofa [National Wildlife Refuge].” Id. at 10.

The Kofa Bighorn Investigative Report was consistent with
the Service’s comprehensive management plan, which like-
wise stressed that bighorn sheep must be supplied with water
to survive. Specifically, the management plan explained that

[i]n the extremely dry Sonoran Desert ecosystem,
water is the primary habitat component and variable.
Over the years, wildlife managers have learned to
manipulate the conservation of water in the desert
for wildlife management purposes. . . . Kofa NWR
has a long history of water hole development proj-
ects aimed at improving wildlife numbers and distri-
bution throughout the refuge.

Kofa Management Plan at 31.3 The Kofa Management Plan
3
Water developments in the Refuge have been a longstanding conserva-
tion tool of the bighorn sheep in the Kofa area. As early as 1937, refuge
20364 WILDERNESS WATCH v. USFWS
further explained that “[e]ven with . . . improvements some
[water] tanks occasionally go dry.” Id. “To prevent large scale
wildlife movement away from these areas, or even worse,
wildlife die offs, water is hauled to these drought susceptible
tanks when needed.” Id. Moreover, the Service addressed the
need for “artificial water catchments” to help preserve big-
horn sheep in the Kofa. Id. at 36; see also id. at 38 (“The
development of water sources for the bighorn sheep has been
an important factor in species recovery since the 1950s.”); id.
at 39 (“Strategic water development programs” for bighorn
are a “key management tool[ ] in the restoration of moribund
[bighorn] populations to historic carrying capacities.”) (inter-
nal quotation marks omitted). Thus, as obvious as the need for
water is in the desert Southwest, the Service never “assum[ed]
that water structures [were] necessary,” as the majority
asserts. Maj. Op. at 20354. Rather, the Service arrived at this
conclusion after carefully documenting the impact of water
availability on the survival of the bighorn.

After explaining why—as a general proposition—water
structures are necessary for the survival of the bighorn, the
Service explained why the two particular water structures at
issue here—the Yaqui and McPherson tanks—were neces-
sary. Specifically, the Service noted that the Yaqui and
McPherson tanks were “considered to be critical to bighorn
sheep, based on their locations in sheep habitat and documen-
tation of sheep use.” Kofa Bighorn Investigative Report at 9.
The Service further explained that “permanent water sources

managers were discussing water developments and predator control as
methods to conserve the population. David Brown, Early History, in THE
DESERT BIGHORN SHEEP IN ARIZONA 7 (Raymond M. Lee, ed., 1993). Since
the 1950s, the AGFD helped develop over 100 water sources for bighorn
sheep, and in 1968 non-profit organizations began coordinating volunteers
who offered to improve and maintain sheep water sources in cooperation
with Arizona and the federal government. Kofa Management Plan at 38;
see also William Werner, Water Development, in THE DESERT BIGHORN
SHEEP IN ARIZONA at 163.
 WILDERNESS WATCH v. USFWS 20365
for desert bighorn sheep are relatively clustered, leaving large
areas of desert bighorn sheep habitat without permanent
water” and that the planned Yaqui and McPherson tanks were
“relatively distant” from other existing, permanent water
sources.4 Kofa Minimum Tool Analysis at 1. Thus, the Yaqui
and McPherson tanks “would fill gaps in the eastern portion
of the Kofa Mountains and in the McPherson Pass area.” Id.
Aside from highlighting the remote locations of the Yaqui and
McPherson tanks, the Service also explained that redevelop-
ing these two tanks “would provide reliable, year-round water
for desert bighorn sheep at two locations . . . where the exist-
ing Yaqui and McPherson Tanks have not always been reli-
able and have been very difficult, logistically, to maintain.”
Id. The Service further stressed the unreliability of the exist-
ing water tanks when explaining why the project was a rede-
velopment: the project involved the installation of “a modern
design requiring little water augmentation . . . in the vicinity
of an existing, non-functional or unreliable source.” Id.
(emphasis added).

The Service then considered alternatives: (1) not to rede-
velop the Yaqui or McPherson tanks, (2) to redevelop the
tanks using mechanized means, or (3) to redevelop the tanks
through non-mechanized means. See Kofa Minimum Tool
Analysis at 2-5. It rejected the first alternative—doing nothing
—because “[w]ithout improvements to the current distribution
of permanent water, the desert bighorn sheep population
could be expected to continue to decline,” while providing
water would “assist[ ] lactating ewes in milk production”
thereby “improv[ing] lamb survival, which is critical to popu-
lation recovery.” Id. at 3. The Service characterized the option
of doing nothing as “failing to meet its responsibilities for
4
The location of these tanks was critical because the “optimum water
distribution” for the bighorn is two miles. William Werner, Water Devel-
opment, in THE DESERT BIGHORN SHEEP IN ARIZONA at 164. “[G]ood distri-
bution of water” helps disperse the sheep, reducing stress and disease
transmission. Id.
20366 WILDERNESS WATCH v. USFWS
wildlife and habitat management . . . [and] its legal or policy
requirements.” Id. at 4. Of the two remaining alternatives, the
Service recommended the second—mechanized redevelop-
ment of the Yaqui and McPherson tanks—because using vehi-
cles and mechanized tools would minimize the time its
employees spent in the wilderness (three days versus two to
three weeks for non-mechanized redevelopment).

Based on the documents discussed above, the Service ulti-
mately determined that there were no other “less intrusive
actions that can be taken or that should be tried first inside or
outside wilderness” to reverse the decline of the bighorn and
that the “activity [could not] be accomplished outside of [the]
wilderness.” Kofa Minimum Requirements Analysis at 1. The
Service then evaluated the potential adverse effects on the
wilderness character and concluded that the project should
proceed because “[w]ildlife is a wilderness resource” and
“[t]he proposed action is intended to restore and maintain
wildlife and wildlife habitat.” Id. at 2. Significantly, the Ser-
vice even explained how redeveloping the Yaqui and McPher-
son tanks would actually increase the wilderness character of
the land: “Overall, the impact of maintenance activities in the
Kofa Wilderness would decrease since very little water haul-
ing after construction is expected to take place.” Kofa Cate-
gorical Exclusion at 5.5
5
Once the Service concluded that additional water structures were nec-
essary for the recovery of the bighorn, the Service took great care to pre-
serve the wilderness character of the land. The Service’s respect for
wilderness can be seen both from the locations chosen for the two water
structures and from the manner in which the Service redeveloped the
Yaqui and McPherson tanks. First, most of the redeveloped Yaqui tank is
located just outside wilderness—indeed, only two or three “substantially
unnoticeable” water diversion weirs are located on wilderness land—while
the redeveloped McPherson tank is located inside wilderness, but within
0.1 miles of a designated road. Kofa Categorical Exclusion at 5. These
strategic locations show that the Service sought to minimize intrusions on
wilderness land. Second, the Service completed the work in three days,
removed tracks left by workers and vehicles, covered visible portions of
the water structures to blend them into the natural habitat, and replanted
nearby plants. These efforts show the Service restored, as much as possi-
ble, the wilderness character of the land.
 WILDERNESS WATCH v. USFWS 20367
The majority nevertheless argues that “nowhere in the
record does the . . . Service articulate why the action taken is
necessary to meet the minimum requirements of the Act,”
Maj. Op. at 20354-55 (alterations omitted), and that the Ser-
vice did not address “the key question—whether water struc-
tures were necessary at all,” leaving that question “entirely
unanswered and unexplained.” Id. at 20352. The record belies
the majority’s claim. Looking at these documents as a whole,
the Service articulates repeatedly that the bighorn sheep need
water to survive and that the existing water sources are not
adequate for sheep in the Kofa Mountains and the McPherson
pass area. See, e.g., Kofa Bighorn Investigative Report at 8-9
(stating that “water distribution is a critical habitat variable
for desert bighorn, . . . [sheep are] dependen[t] on reliable
water sources, . . . a better distribution of permanent water
supplies is needed to provide water in all areas of suitable
sheep habitat, . . . new waters might need to be built, [and] . . .
construction in wilderness should remain an option if a wil-
derness location best meets wildlife management needs”);
Kofa Minimum Tools Analysis at 3 (stating that “[w]ithout
improvements to the current distribution of permanent water,
the desert bighorn sheep population could be expected to con-
tinue to decline”); Kofa Minimum Requirements Analysis at 1
(stating that “there [are no] other less intrusive actions,” other
than redeveloping the two water tanks, that would help the
sheep recover); Kofa Categorical Exclusion at 4 (stating that
“[w]ithout improving the distribution and reliability of avail-
able water, it is likely that the desert bighorn sheep will con-
tinue to decline”).

Admittedly, the Service could have been more didactic in
its explanation, locating it in one document rather than sev-
eral. But because the Wilderness Act “does not specify any
particular form or content” for the Service’s finding of neces-
sity, High Sierra Hikers, 390 F.3d at 647, the Service does not
fail to make a finding of necessity simply because it does not
explain its reasoning in a single document. The majority,
however, accuses me of “cobbl[ing] up [my] own explanation
20368 WILDERNESS WATCH v. USFWS
[of why water structures were necessary] from disparate parts
of the various reports . . . [when] it is the Service’s explana-
tion, or lack thereof, that we must review.” Maj. Op. at 20351
n.8. With respect, the majority misses the point. The majority
wants the Service to hold us by the hand and to slowly and
exhaustively explain to us its actions at every junction along
the way. But the Service’s reasoning and conclusions are
readily discernable from the record, and so we are required to
uphold the Service’s decision to redevelop the two water
tanks. See Alaska Dept. of Envtl. Conservation v. EPA, 540
U.S. 461, 497 (2004) (“Even when an agency explains its
decision with less than ideal clarity, a reviewing court will not
upset the decision on that account if the agency’s path may
reasonably be discerned.”) (internal quotation marks omitted);
see also River Runners, 593 F.3d at 1078 (holding that
absence of a specific discussion of the amount of motorized
traffic found necessary and appropriate does not require over-
turning the agency’s action if the agency’s consideration of
the motorized traffic necessary “can reasonably be discerned”
from the documents provided by the agency). We have no
right to impose additional burdens on the agency because we
think we can improve its handling of the matter. See Vermont
Yankee Nuclear Power Corp. v. Natural Res. Def. Council,
435 U.S. 519, 546 (1978) (“[I]f courts continually review
agency proceedings to determine whether the agency
employed procedures which were, in the court’s opinion, per-
fectly tailored to reach what the court perceives to be the
‘best’ or ‘correct’ result, judicial review would be totally
unpredictable.”).

B

In addition to holding that the Service acted arbitrarily and
capriciously because it never stated that water structures were
necessary, the majority also holds the Service acted arbitrarily
and capriciously because “nowhere in the record does the Ser-
vice explain why [addressing other possible causes for the
bighorn’s decline], alone or in combination, are insufficient to
 WILDERNESS WATCH v. USFWS 20369
restore the population of the bighorn sheep.” Maj. Op. at
20353-54. But the Service did not consider the need for the
Yaqui and McPherson tanks in isolation, as the majority sug-
gests. Rather, these tanks—which service a remote area of the
Kofa—are part of a comprehensive plan for promoting the
survival of the bighorn. The Service also analyzed other pos-
sible causes of the bighorn’s decline and incorporated recom-
mendations regarding these causes into its overall proposal.
This comprehensive analysis discharges the Service’s obliga-
tion to consider other possible causes.

1

Nevertheless, the majority argues that redeveloping the
water tanks was not “necessary” because “many factors other
than access to water, either alone or in combination, might
suffice to restore the population of bighorn sheep.” Maj. Op.
at 20352. The majority points to four factors: translocation,
human disturbance, mountain lion predation, and hunting. Id.
at 31-32. But the majority is wrong. The Service did consider
these factors in the 2007 Kofa Bighorn Investigative Report.
Specifically, the Service found that each factor contributed in
some way to the decline in the bighorn sheep population from
813 to 390 between 2000 and 2006, but concluded that
drought was the principal explanation for the decline.

For example, with regard to translocation, the Service
observed that “[t]ransplants of sheep from the Kofa were con-
ducted nearly every year from 1979 through 1998 with no
apparent decline in population.” Kofa Bighorn Investigative
Report at 18. No sheep were transplanted from the Kofa in
2000, 2003, or 2004 “because of drought conditions.” Id. In
2005, thirty-one sheep were translocated, and the report
acknowledged that “[w]hile not the ultimate cause of the pop-
ulation decline, the 2005 transplant may have contributed to
the low numbers” in 2006. Id. In 2006, because the levels of
sheep were “historically low,” the Service discontinued the
20370 WILDERNESS WATCH v. USFWS
transplant program until the bighorn sheep population
increased to an average of 800. Id. at 18-19.

With respect to human disturbance, the investigative report
acknowledged that a “study conducted from 1977 to 1984
documented strong reactions . . . from Kofa sheep in response
to 1 or 2 people” and that “[f]requent human disturbance of
ewes may cause them to abandon the[ir] areas for less optimal
habitat.” Id. at 17. To address these concerns, the report rec-
ommended conducting surveys to identify critical lambing
areas and instituting seasonal closures if substantial recre-
ational use is observed in these areas. Id. These measures
would certainly have some positive effect on the bighorn’s
recovery. But given that hikers have been present in the Kofa
for decades and that their presence has not historically corre-
lated with a decline in the bighorn’s population, the Service
could reasonably conclude that addressing human disturbance
alone would not solve the bighorn’s decline.

With respect to predators, particularly mountain lions, the
investigative report found that “[i]t is unlikely that lion preda-
tion alone accounts for the decline observed.” Id. at 13. The
report noted that “[t]here are no verified records of mountain
lions on the refuge between 1944 and 2001” but “a female
lion and 2 kittens were spotted” in 2003 and “at least 5 lions
[were documented] on the refuge in 2006.” Id. at 12. The
report acknowledged that researchers did not know much
about the threat mountain lions posed to the bighorn sheep
population because “[l]ittle is known about the . . . specific
diet of mountain lions on Kofa NWR.” Id. The report found
“evidence that some mountain lions in bighorn sheep habitat
may kill multiple sheep within a year, some may kill only one
sheep within a year, and some may kill no sheep at all. The
key factor is that lion-sheep interactions must be studied . . . .”
Id. at 13. The report also stated that “predation is generally
believed to rarely threaten population survival.” Id. at 11. The
report proposed further study and recommended collaring
 WILDERNESS WATCH v. USFWS 20371
lions and sheep to “[d]etermine [the] cause and extent of pre-
dation.” Id. at 14.

Notwithstanding the Service’s explanation of the need for
further study, the majority speculates that addressing preda-
tion alone could be sufficient to restore the bighorn sheep
population. See Maj. Op. at 20352-53. The majority places far
too much stock in the explanatory power of the mountain
lions. The report makes clear that the relatively recent appear-
ance of mountain lions in the Kofa may contribute to, but can-
not explain, the bighorn’s decline. The bighorn herds in the
Kofa declined by more than 400 sheep—a more than fifty per-
cent decline—between 2000 and 2006. No mountain lions
were even spotted until 2003, and only five were observed in
2006 in the 600,000 acre refuge. Id. at 20338-39. Most
importantly—and this is one of the reasons the report recom-
mended further study and made radio collars for lions and
sheep a priority—the report stated that mountain lions were
believed to have killed only one bighorn sheep in 2005 and
2006. Id. The presence of mountain lions in the Kofa cannot
account for a 400-sheep decline that began three years before
any lions were even observed. I thus respectfully disagree
with the majority’s claim that “[ending predation by mountain
lions] could have met the goal of conserving bighorn sheep
without having to construct additional structures within the
wilderness area.” Maj. Op. at 20352. There is no support for
such conclusion in the record.

Lastly, the investigative report addressed hunting. It
observed that Arizona issues hunting permits in an auction to
support bighorn sheep management and conservation and that
anywhere from five to seventeen bighorn sheep permits are
issued each year. Kofa Bighorn Investigative Report at 19.
The majority comments that “the report recommends, without
explanation, that hunting be continued in the Refuge.” Maj.
Op. at 20353. The Service did explain this. The permits
authorize hunting of mature rams only. The Service cited
studies showing that “a healthy vigorous herd can be main-
20372 WILDERNESS WATCH v. USFWS
tained by conservative harvest of mature rams . . . .” Kofa
Bighorn Investigative Report at 19 (emphasis added). The
hunting of mature rams has little effect on the survival of the
sheep.

After reviewing the Service’s various reports, it becomes
apparent that the Service took a comprehensive look at the
problem of declining bighorn populations and the various fac-
tors that may have contributed to that decline. Then, based on
its scientific and technical expertise and drawing on decades
of its own and Arizona’s experience in conserving the bighorn
in the Kofa, the Service reasonably concluded that supplying
water to the bighorn was necessary to ensure the survival of
a critical herd. That other factors—predation, translocation,
hunting, and human disturbance—might come into play does
not discredit the Service’s determination that drought was the
critical factor leading to the bighorn’s decline.6 The majority
errs by failing to afford the Service’s scientific determination
the special deference it is due. See, e.g., Arizona Cattle Grow-
ers’ Ass’n v. Salazar, 606 F.3d 1160, 1167 (9th Cir. 2010)
(“[W]hen an agency is acting within its expertise to make a
scientific determination a reviewing court must generally be
at its most deferential.”) (internal quotation marks omitted);
Ctr. For Biological Diversity v. Kempthorne, 588 F.3d 701,
707 (9th Cir. 2009) (“[High] deference is especially warranted
6
For example, the Service found that “[s]evere drought conditions in
1996 and 2002 were likely causes for the bighorn population dips
observed on the 1997 and 2003 aerial population surveys.” Kofa Bighorn
Investigative Report at 7. This finding was unsurprising because “extreme
ambient temperatures, reduced moisture content of forage, and mating
activities necessitate additional water intake, and thus [create] a depen-
dence on reliable water sources.” Id. at 8. The Service explained that, in
addition to being “a critical habitat variable for desert bighorn, especially
during summer months when temperatures can reach 120 [degrees],”
water distribution affects other mortality factors for the bighorn sheep:
“[d]isease in bighorn sheep is most prevalent when animals are stressed
and during severe drought.” Id. at 8, 15. The report concluded that,
because of water’s critical role in preventing mortality, “a better distribu-
tion of permanent water supplies [was] needed.” Id. at 9.
 WILDERNESS WATCH v. USFWS 20373
when reviewing the agency’s technical analysis and judg-
ments, based on an evaluation of complex scientific data
within the agency’s technical expertise.”) (internal quotation
marks and citation omitted).

2

The majority recognizes that the 2007 report was “a thor-
ough, neutral, and scientific assessment of the many factors
that contribute to sheep mortality,” but faults it for not “as-
sess[ing] the factors relative to each other.” Maj. Op. at
20352. Specifically, the majority argues that High Sierra Hik-
ers requires the Service to conduct a side-by-side, compara-
tive analysis of the factors contributing to the bighorn’s
decline. Maj. Op. at 20354-55. But nothing in High Sierra
Hikers, 16 U.S.C. § 1133(c), or the APA requires a compari-
son of this kind.

In High Sierra Hikers, we interpreted 16 U.S.C.
§ 1133(d)(5) in the context of the Forest Service’s decision to
authorize commercial packers to take groups through a wil-
derness area.7 390 F.3d at 646. We held that the Forest Ser-
vice’s determination that “packstock was needed to provide
access to those people who would otherwise not be able to
gain access for themselves or their gear” supported a finding
of necessity, but that the Forest Service failed to meet the
Act’s requirement of a “specialized” finding of necessity
because the Service could authorize commercial services only
“to the extent necessary.” Id. at 647 (emphasis in original).
Because the Act required that commercial services could be
authorized “to the extent necessary” to realize the recreational
purposes of the area, the court found that the “Forest Service
7
The Wilderness Act generally prohibits commercial enterprises in the
wilderness area, but authorizes commercial services within wilderness
areas “to the extent necessary for activities which are proper for realizing
the recreational or other wilderness purposes of the areas.” 16 U.S.C.
§ 1133(c), (d)(5).
20374 WILDERNESS WATCH v. USFWS
must show that the number of permits granted was no more
than was necessary to achieve the goals of the Act” and that
the Service must “articulate why the extent of such packstock
services authorized by the permits is ‘necessary.’ ” Id.
(emphasis in original). The court emphasized that the lan-
guage “to the extent necessary” required a more specialized
determination, one that balanced the purposes of the Wilder-
ness Area with the antithetical purposes of commercial activ-
ity. Because it failed to conduct a specialized finding of
necessity—that the licenses were issued “to the extent
necessary”—the Service “[a]t best . . . failed to balance the
impact that the level of commercial activity was having on the
wilderness character of the land [and a]t worst . . . elevated
recreational activity over the long-term preservation of the
wilderness character of the land.” Id.

Unlike § 1133(d)(5), § 1133(c) does not require a special-
ized determination of necessity. Section 1133(c) prohibits
structures “except as necessary to meet minimum require-
ments for the administration of the area for the purpose of this
chapter.” Without a qualifier on the word “necessary,” I
would not interpret the statute as requiring a specialized find-
ing of absolute necessity, as the majority does. See Maj. Op.
at 20356 (“Just because [the need for water] affects the
sheep’s viability, the Service is not free to create structures
addressing [the need for water] without regard to any other
variables at play. . . . [T]he Service must, at the very least,
explain why addressing [the need for water] is more important
than addressing the other variables and must explain why
addressing [the need for water] is even necessary at all. . . .”).8

I see no reason to require the Service to show that improv-
8
The practical effect of the majority’s decision—requiring the Service
to show that nothing but these additional water structures will help the
sheep recover—subverts the majority’s disclaimer that it “in no way
hold[s] that the Service must make a finding of absolute necessity.” Maj.
Op. at 20351 n.8.
 WILDERNESS WATCH v. USFWS 20375
ing the bighorn’s access to water at the Yaqui and McPherson
tanks is the only way to stop the decline of the bighorn sheep
population. Indeed, courts have long rejected interpreting
“necessary” to mean “absolutely necessary” or “indispens-
able;”9 as the D.C. Circuit has explained: “[C]ourts have fre-
9
Most obviously, the Supreme Court in McCulloch v. Maryland, 17
U.S. 316 (1819), rejected interpreting the word “necessary” in the Neces-
sary and Proper Clause to mean “always import[ing] an absolute physical
necessity, so strong, that one thing to which another may be termed neces-
sary, cannot exist without that other” and instead found that the word “im-
port[ed] no more than that one thing is convenient, or useful, or essential
to another. To employ the means necessary to an end, is generally under-
stood as employing any means calculated to produce the end, and not as
being confined to those single means, without which the end would be
entirely unattainable.” Id. at 413-14; see also Stenberg v. Carhart, 530
U.S. 914, 937 (2000) (explaining that the word “necessary” in Planned
Parenthood of Southeastern Pennsylvania v. Casey’s “phrase ‘necessary,
in appropriate medical judgment, for the preservation of the life or health
of the mother . . . cannot refer to an absolute necessity or to absolute
proof”).
Other courts have followed suit. In Cellular Telecomm. & Internet
Ass’n v. F.C.C. 330 F.3d 502, 510 (D.C. Cir. 2003), the court deferred to
the FCC Commissioner’s interpretation of “necessary” in 47 U.S.C.
§ 160(a), a statute allowing the FCC to forbear enforcing a regulation or
a statutory provision if certain conditions are met. The court defined nec-
essary as “that which is required to achieve a desired goal” and found that
the term “does not foreclose a particular means to an end merely because
other means are hypothetically available to achieve the desired end.” Id.
Similarly, in Inbesa America, Inc. v. M/V Anglia, 134 F.3d 1035, 1036
(11th Cir. 1998), the court stated that in order for a federal court to have
admiralty jurisdiction over a contract, the elements of the contract must
“pertain directly to and be necessary for commerce or navigation upon
navigable waters. . . . The test we apply in deciding whether the subject
matter of a contract is necessary to the operation, navigation, or manage-
ment of a ship is a test of reasonableness, not of absolute necessity.” Id.
(omission in original). In In re Mile Hi Metal Sys., Inc., 899 F.2d 887,
892-93 (10th Cir. 1990), the court held that the term “necessary modifica-
tions” in the context of a collective bargaining agreement under 11 U.S.C.
§ 1113(b)(1)(A), “does not mean absolutely necessary” to the debtor’s
reorganization but must be “more than potentially helpful.” And in South-
land Royalty Co. v. United States, 582 F.2d 604, 605 (Cl. Ct. 1978), the
court interpreted “necessary” under 26 U.S.C. § 162(a), which allows a
20376 WILDERNESS WATCH v. USFWS
quently interpreted the word ‘necessary’ to mean less than
absolutely essential, and have explicitly found that a measure
may be ‘necessary’ even though acceptable alternatives have
not been exhausted.” Natural Res. Def. Council, Inc. v.
Thomas, 838 F.2d 1224, 1226 (D.C. Cir. 1988) (citations
omitted); see also Sierra Club v. Lyng, 663 F. Supp. 556, 560
(D.D.C. 1987) (interpreting § 1133(d)(1)—which permits the
agency to take such measures in the wilderness “as may be
necessary in the control of . . . insects”—to allow the agency
“to use measures that fall short of full effectiveness so long
as they are reasonably designed to restrain or limit the threat-
ened [insect] infestation”). A determination of absolute neces-
sity would be nearly impossible for scientists and researchers
to make and would render meaningless § 1133(c)’s exception
to the structure prohibition.

Here, the Service took a tried-and-true approach: it looked
at the potential impacts on the bighorn population and pro-
posed a comprehensive solution. Rather than trying to isolate
a one-size-fits-all solution, the Service moved forward on all
fronts. It addressed predators, hunting, translocation, human
disturbance, and water structures. The Service recognized that
some of its proposals called for immediate action, while oth-
ers required further study. Thus, for example, the Service did
not recommend killing mountain lions, but studying them; it
recommended seeking funding for GPS collars, but noted that
such collars only “last 1-2 years, which would require fre-
quent recollaring for long term monitoring efforts.” Kofa Big-
horn Investigative Report at 14. By contrast, as any denizen
of the Southwest knows, obtaining water requires short-term
planning, because finding adequate water in the desert is both

deduction for “all the ordinary and necessary expenses paid or incurred
during the taxable year in carrying on any trade or business.” The court
held, “[a]n expense satisfies the requirement of being ‘necessary’ within
the statute if it is ‘appropriate and helpful’ ‘to the development of the tax-
payer’s business.’ ” Id.
 WILDERNESS WATCH v. USFWS 20377
an immediate and a constant concern. It is thus far from clear
that the Service would have had a good basis for comparing
the efficacy of mountain lion control with rebuilding the
Yaqui and McPherson tanks, and nothing in the Wilderness
Act suggests the Service must ignore immediate needs to
compare them with long-term proposals. See Lyng, 663 F.
Supp. at 560 (“The degree of efficacy of various . . . methods
[of controlling insect infestation] is not to be debated between
various scientists and resolved before this Court. The [agen-
cy’s] judgment that the control measures authorized are rea-
sonably efficacious is entitled to respect under [the APA].”).

Although the Service did not do a side-by-side comparative
analysis of the various causes of the bighorn’s decline, noth-
ing in the Wilderness Act, the Service’s interpretation of the
Act, the APA, or our decisions obligates the Service to con-
duct its review in that way. In fact, we have eschewed impos-
ing such form on the Service. See High Sierra Hikers, 390
F.3d at 646-47 (“The Wilderness Act is framed in general
terms and does not specify any particular form or content for
[the Service’s finding of necessity.]”). I would thus decline to
hold the Service to a particular form or content to determine
necessity. As long as the explanations the Service offered to
support its finding of necessity are not implausible, do not
omit an important aspect of the problem, and do not run
counter to the evidence presented, I would uphold the Ser-
vice’s finding under the APA. See The Lands Council, 537
F.3d at 993.

The majority may not think that the Yaqui and McPherson
tanks are necessary, but whether these two water structures
are necessary or not is at best debatable. The Plaintiffs may
consider bighorn management contrary to the natural order
and an affront to the idea of wilderness, but the Service has
declared—and the majority today affirms—that preserving
bighorn in the Kofa is consistent with the Service’s charge
from Congress. See Maj. Op. at 20349. Where Congress has
placed such decision-making power in the Service, the major-
20378 WILDERNESS WATCH v. USFWS
ity errs by failing to “defer to the informed discretion of the
responsible federal agenc[y].” Marsh v. Or. Natural Res.
Council, 490 U.S. 360, 377 (1989) (quotation marks omitted).

II

Ultimately, the majority concludes “the Service must pro-
vide enough evidence and explanation in the record to assure
this court that it fully considered [alternative factors for the
bighorn’s decline] and nevertheless rationally concluded that
new water structures are, in fact, necessary.” Maj. Op. at
20357. I think the Service did just that. But even if I were to
agree that the record in this case is “wholly inadequate,” I
would not remand this case to the district court “with instruc-
tions to determine the appropriate remedy.” Id. When both
Supreme Court and circuit precedent mandate a remand to the
agency for a more adequate explanation of the agency’s rea-
soning, an open-ended remand to the district court is but an
exercise in futility. The only remedy the district court should
consider is remand to the Service for further explanation. See
Florida Power & Light Co. v. Lorion, 470 U.S. 729, 744
(1985) (“[I]f the reviewing court simply cannot evaluate the
challenged agency action on the basis of the record before it,
the proper course, except in rare circumstances, is to remand
to the agency for additional investigation or explanation.”);
Humane Soc’y of the U.S. v. Locke, ___ F.3d ___, 2010 WL
4723195, at *5 (9th Cir. Nov. 23, 2010) (holding that when
the agency’s “explanation is incomplete and inadequate to
permit meaningful judicial review,” the proper remedy is a
remand “to afford the agency the opportunity to . . . articulate
a reasoned explanation for its action”); see also Seavey v.
Barnhart, 276 F.3d 1, 12 (1st Cir. 2001) (“When an agency
has not considered all relevant factors in taking action, or has
provided insufficient explanation for its action, the reviewing
court ordinarily should remand the case to the agency.”); Pub-
lic Power Council v. Johnson, 674 F.2d 791, 794 (9th Cir.
1982) (“When there is a need to supplement the record to
explain agency action, the preferred procedure is to remand to
 WILDERNESS WATCH v. USFWS 20379
the agency for its amplification.”) (citation omitted); 3
CHARLES H. KOCH, JR., ADMINISTRATIVE LAW AND PRACTICE
§ 8:32 (3d ed. 2010) (“Remand is particularly appropriate
where the agency justification is inadequate . . . [because] the
agency should be given every opportunity to justify its deci-
sion.”).

For the reasons discussed above, the majority engrafts a
new procedural requirement onto the Wilderness Act and the
APA. Before building a permanent structure within wilder-
ness, the Service must now make a thoroughly documented,
formalized finding of necessity accompanied by the compara-
tive, multi-factor, side-by-side analysis the majority dictates.
But even more consequential is the majority’s holding that the
Service’s failure to offer an explanation that satisfies the
majority’s new criteria is fatal to its case: without creating this
judicially-mandated record, the agency’s action is per se arbi-
trary and capricious. But

[t]here is a fine line between agency reasoning that
is “so crippled as to be unlawful” and action that is
potentially lawful but insufficiently or inappropri-
ately explained. In the former circumstance, the
court’s practice is to vacate the agency’s order, while
in the later the court frequently remands for further
explanation (including discussion of relevant factors
and precedents) while withholding judgment on the
lawfulness of the agency’s proposed action.

Radio-Television News Directors Ass’n v. F.C.C., 184 F.3d
872, 888 (D.C. Cir. 1999); see also Checkosky v. SEC, 23
F.3d 452, 463 (D.C. Cir. 1994) (Silberman, J., concurring)
(citing some of the “many instances where [the court has]
remanded to an agency for a better explanation before finally
deciding that the agency’s action was arbitrary and capri-
cious”) (emphasis added).

Nevertheless, the majority concludes the Service’s action
was arbitrary and capricious because the Service failed to
20380 WILDERNESS WATCH v. USFWS
consider an important aspect of the problem—“namely, the
failure to consider whether new water structures are necessary
at all.” Maj. Op. at 20355. The majority’s holding rests on the
following syllogism: (1) arbitrary and capricious agency
actions must be set aside; (2) all inadequately explained
agency actions are arbitrary and capricious; (3) therefore,
inadequately explained agency actions must be set aside. I
disagree with the second proposition of this syllogism; not all
inadequately explained agency actions are arbitrary and capri-
cious. The majority’s approach sets aside agency actions

even when the reviewing court is unsure of the agen-
cy’s reasoning. This assertion, if accepted, would
fundamentally alter the role of the judiciary vis-a-vis
administrative agencies by forcing courts to decide
that the agency’s action is either unlawful or lawful
on the first pass, even when the judges are unsure as
to the answer because they are not confident that
they have discerned the agency’s full rationale. This
assertion finds support in neither logic nor precedent.

Checkosky, 23 F.3d at 463 (Silberman J., concurring).

The majority deflects analysis of the appropriate remedy in
this case by giving the district court a choice: on remand, the
district court may either require the Service to dismantle the
water structures or may remand the matter to the Service for
a fuller explanation of the Service’s decision. The problem, of
course, is that the majority errs by giving the district court this
very choice. See 1 RICHARD J. PIERCE JR., ADMINISTRATIVE LAW
TREATISE § 8.5 (5th ed. 2010) (“If a court concludes that the
explanation provided by the agency . . . is too terse to allow
the court to apply the arbitrary and capricious test, the only
remedy authorized by [the Supreme Court] is a remand to the
agency for further explanation.”) (emphasis added). Addition-
ally, the majority even hints the Service may have waived its
right to object to any remedy other than the dismantling of the
structures. See Maj. Op. at 20357 n.10. I offer just one com-
 WILDERNESS WATCH v. USFWS 20381
ment in reply: I find it mind-boggling to think the Service can
waive what courts must do.

*****

An inescapable theme runs through the Service’s various
reports: water is, and historically has been, critical to conserv-
ing bighorn populations in the Kofa, and any proposal that
does not take account of the herds’ need for additional water
sources is unlikely to succeed. In my view, the record in this
case clearly indicates the agency conducted a comprehensive
analysis of the possible causes for the bighorn’s decline and
reasonably decided to address the most pressing cause. Scat-
tered over three reports, the Service’s finding of necessity is
not as graceful or as elegant as it could have been. But, unlike
judges at a pageant competition, our proper role is not to
grade the Service on poise and style. Rather, as the Supreme
Court has consistently held, even if the Service does not
explain its decision with “ideal clarity,” we must uphold the
decision “if the agency’s path may reasonably be discerned.”
Bowman Transp., Inc. v. Arkansas-Best Freight Sys., Inc., 419
U.S. 281, 286 (1974). Here, the Service’s reasoning for rede-
veloping two critical but previously unreliable water sources
can readily be discerned. Because the majority requires the
Service to do more than it must do, I dissent.