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No. 10746641
United States Court of Appeals for the Ninth Circuit
San Luis Obispo Coastkeeper v. County of San Luis Obispo
No. 10746641 · Decided December 3, 2025
No. 10746641·Ninth Circuit · 2025·
FlawFinder last updated this page Apr. 2, 2026
Case Details
Court
United States Court of Appeals for the Ninth Circuit
Decided
December 3, 2025
Citation
No. 10746641
Disposition
See opinion text.
Full Opinion
FOR PUBLICATION
UNITED STATES COURT OF APPEALS
FOR THE NINTH CIRCUIT
SAN LUIS OBISPO No. 24-7807
COASTKEEPER; LOS PADRES
D.C. No.
FORESTWATCH; CALIFORNIA
2:24-cv-06854-
COASTKEEPER ALLIANCE;
SPG-AS
ECOLOGICAL RIGHTS
FOUNDATION,
OPINION
Plaintiffs - Appellees,
v.
COUNTY OF SAN LUIS OBISPO,
Defendant - Appellant.
Appeal from the United States District Court
for the Central District of California
Sherilyn Peace Garnett, District Judge, Presiding
Argued and Submitted August 12, 2025
Pasadena, California
Filed December 3, 2025
Before: Jacqueline H. Nguyen, Danielle J. Forrest, and
Lawrence VanDyke, Circuit Judges.
2 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
Opinion by Judge Nguyen;
Concurrence by Judge VanDyke
SUMMARY *
Endangered Species Act
The panel vacated the district court’s mandatory
preliminary injunction requiring the County of San Luis
Obispo to take certain actions in its management of the
Lopez Dam and Reservoir, and remanded for further
proceedings, in a case in which environmental non-profit
organizations (“the NGOs”), who allege decades of
noncompliance with proper permitting processes, seek to
protect and improve the habitat of threatened South-Central
California Coast steelhead trout that reside downstream from
Lopez Dam.
The NGOs contend that the County’s operations are
causing an unlawful take of the steelhead in violation of
section 9 of the Endangered Species Act (“ESA”) and are
separately violating California Fish & Game Code
(“CFGC”) section 5937 by failing to release sufficient water
to maintain the fish in “good condition.”
Also populating the waterway is the California red-
legged frog and the tidewater goby—species equally entitled
to the ESA’s protections. The County contends that the
*
This summary constitutes no part of the opinion of the court. It has
been prepared by court staff for the convenience of the reader.
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 3
preliminary injunction, though beneficial to the steelhead,
will endanger the other species.
A mandatory preliminary injunction, unlike a
prohibitory one, does not serve to preserve the status quo
pending resolution of the merits but instead compels the
nonmoving party to take affirmative action.
Deriving from the Supreme Court’s ruling in Tenn.
Valley Auth. v. Hill, 437 U.S. 153, 184 (1978), as expanded
by the Ninth Circuit, courts have no discretion to balance
equities or the public interest when considering whether to
grant a preliminary or permanent injunction in any ESA
case. This is because Congress already did so in deciding
that endangered species would take precedence “whatever
the cost.”
This rationale, however, collapses where protecting one
listed species might jeopardize another—as here. The
tension is even sharper where the injunction was mandatory,
not prohibitory.
The panel held, accordingly, that when mandatory
injunctive relief under the ESA may benefit one protected
species at the expense of other protected species, a court
must consider competing equities and the public interest as
to those other species. This holding does not open the door
to all the usual equities—economic, developmental, or
otherwise—as Congress was clear that endangered species
come first, whatever the cost.
Here, the district court summarized the evidence
regarding the California red-legged frog and tidewater goby,
but it did not weigh the balance of equities or the public
interest, and it drew no conclusions about how the evidence
should factor into its decision. The district court’s analysis,
4 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
therefore, did not satisfy the standard for a mandatory
preliminary injunction under the ESA. The panel instructed
the district court, on remand, to weigh the evidence on all
affected species.
The panel agreed with the district court’s application of
the full test set forth in Winter v. Natural Resources Defense
Council, Inc., 555 U.S. 7 (2008), to the NGOs’ request for
injunctive relief pursuant to CFGC section 5937. But for the
reasons set forth in the ESA context, the district court’s
actual analysis of the equities and the public interest fell
short. The district court’s CFGC section 5937 analysis
likewise remains unfinished, so the panel vacated the
preliminary injunction on this claim as well.
Concurring, Judge VanDyke joined the majority in
full. He wrote separately to emphasize the demanding
standard that must be met before a district court may issue a
mandatory preliminary injunction, a standard that has
become even harder to satisfy in cases like this one which
involve the complicated interplay between different species.
COUNSEL
Christopher Sproul (argued), Brian Orion, and Marla Fox,
San Francisco, California; Drevet J. Hunt, California
Coastkeeper Alliance, Sacramento, California; for Plaintiffs-
Appellees.
Paul S. Weiland (argued) and Benjamin Z. Rubin, Nossaman
LLP, Irvine, California; Brian Ferrasci-O'Malley, Nossaman
LLP, Seattle, Washington; for Defendant-Appellant.
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 5
Damien M. Schiff and Charles T. Yates, Pacific Legal
Foundation, Sacramento, California, for Amici Curiae
Pacific Legal Foundation and California Farm Bureau
Federation.
Barbara A. Brenner and Kerry A. Fuller, White Brenner
LLP, Sacramento, California, for Amicus Curiae City of
Arroyo Grande.
Jeremy N. Jungreis and Scott C. Cooper, Rutan & Tucker
LLP, Irvine, California, for Amicus Curiae Association of
California Water Agencies, California State Association of
Counties, and California Special Districts Association.
Peter M. K. Frost, Western Environmental Law Center,
University of Oregon School of Law, Eugene, Oregon, for
Amicus Curiae Law School Faculty.
Adam Keats, Law Office of Adam Keats PC, San Francisco,
California; M. Benjamin Eichenberg and Eric J. Buescher,
San Francisco Baykeeper, Oakland, California; for Amici
Curiae California Water Impact Network, Center for
Biological Diversity, San Francisco Baykeeper, Sierra Club,
Friends of the River, Bring Back the Kern, Kern Audubon
Society, Kern River Parkway Foundation, and
Environmental Defense Center.
Deborah A. Sivas, Matthew J. Sanders, and Amanda Zerbe,
Environmental Law Clinic, Mills Legal Clinic at Stanford
Law School, Stanford, California, for Amici Curiae
Fisheries Biologists Peter Moyle, Theodore Grantham, and
Karrigan Börk.
6 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
OPINION
NGUYEN, Circuit Judge:
Recognizing that the extinction of wildlife species
carries grave “esthetic, ecological, educational, historical,
recreational, and scientific” consequences, Congress enacted
the Endangered Species Act (“ESA”), 16 U.S.C. § 1531, et
seq., in 1973. See id. § 1531(a)(1)–(3). In so doing,
Congress created a statutory scheme intended “to halt and
reverse the trend toward species extinction, whatever the
cost.” Tenn. Valley Auth. v. Hill, 437 U.S. 153, 184 (1978)
(“TVA”). Since its passage, the ESA has served as a
powerful tool frequently invoked by non-governmental
organizations working to protect threatened or endangered
species. These organizations often seek preliminary
injunctions to halt activities that could harm such species.
The Supreme Court in TVA recognized that when evaluating
the equities and the public interest, “the balance has been
struck in favor of affording endangered species the highest
of priorities,” id. at 194, and “the value of endangered
species [is] ‘incalculable,’” id. at 187. This court, therefore,
does not consider the balance of equities and the public
interest when deciding whether to issue preliminary
injunctions under the ESA. See Nat’l Wildlife Fed’n v.
Burlington N. R.R., 23 F.3d 1508, 1511 (9th Cir. 1994)
(“[T]he ESA demonstrates Congress’ determination that the
balance of hardships and the public interest tips heavily in
favor of protected species.”); Cottonwood Env’t L. Ctr. v.
U.S. Forest Serv., 789 F.3d 1075, 1090 (9th Cir. 2015)
(Congress has “strip[ped] courts of at least some of their
equitable discretion in determining whether injunctive relief
is warranted.”).
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 7
This case, however, tests the logic of our approach. The
County of San Luis Obispo (“County”) appeals a mandatory
preliminary injunction requiring it to take certain actions in
its management of the Lopez Dam and Reservoir. A group
of environmental non-profit organizations—San Luis
Obispo Coastkeeper, Los Padres ForestWatch, California
Coastkeeper Alliance, and Ecological Rights Foundation
(collectively, “the NGOs”)—filed suit against the County,
alleging decades of noncompliance with proper permitting
processes. The NGOs sought an injunction to protect and
improve the habitat of threatened steelhead trout that reside
in Arroyo Grande Creek (“AG Creek”) downstream from the
Lopez Dam. But the steelhead is not the only ESA-listed
species living in AG Creek. Also populating the waterway
is the California red-legged frog and the tidewater goby—
species equally entitled to the ESA’s protections. The
County contends that the preliminary injunction, though
beneficial to the steelhead, will endanger the other species.
We hold that when mandatory injunctive relief under the
ESA may benefit one protected species at the expense of
other protected species, a court must consider competing
equities and the public interest as to those other species.
Because the district court here did not do so, we vacate the
preliminary injunction and remand for further proceedings.
I. FACTUAL AND STATUTORY BACKGROUND
A.
The steelhead is an anadromous fish, meaning that it
hatches in freshwater streams, migrates to the ocean to
mature, and then returns as an adult—often multiple times
during its lifespan—to spawn. The various stages of its
lifecycle depend on high, pulsing flows of freshwater from
creeks and rivers, such as AG Creek. During the wet months
8 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
of January through March, the surge of freshwater entering
the ocean signals to adult steelhead that it is time to migrate
upstream and spawn. When they reach the mouth of the
creek, stronger streamflow helps form and sustain coastal
lagoons, which serve as important developmental habitats
before the juvenile steelhead head to sea. In drier periods,
however, sandbars often form between the lagoon and the
ocean—effectively cutting off access. The high flows
breach those sandbars, allowing adult steelhead to reenter
the stream to spawn and juveniles to exit to the ocean.
Flow levels also shape the quality of the streambed itself.
Steelhead need gravel streambeds with minimal sediment to
support egg nests, and high flows clear fine sediment from
the streambed, exposing the coarser gravel substrates.
Juvenile steelheads also require adequate streamflow to
facilitate natural variations in channel shape and create the
pools and riffles that are essential for feeding, resting, and
overall survival.
B.
The National Marine Fisheries Service (“NMFS”)
regulates marine and anadromous fish, including the
steelhead, under the ESA. Since 1997, the NMFS has listed
the steelhead of the South-Central California Coast (“SCCC
steelhead”), which includes the steelhead in AG Creek, as
threatened. See 62 Fed. Reg. 43,937, 43,953 (Aug. 18,
1997); 71 Fed. Reg. 834, 857 (Jan. 5, 2006). In 2006, the
NMFS further identified the SCCC steelhead as a Distinct
Population Segment (“DPS”) of the fish species. 71 Fed.
Reg. at 859. That designation reflects the agency’s
determination that the SCCC steelhead is genetically
important to the species as a whole and merits protection to
preserve its genetic diversity and adaptive potential. The
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 9
NMFS has also designated the steelhead in AG Creek as a
“Core-1” population, meaning that its survival is “vitally
important to the recovery and survival of the broader
Steelhead DPS as a whole.”
The AG Creek coastal watershed is over 150 square
miles located in the west-central portion of the County. As
a result of extensive habitat degradation elsewhere, it is one
of the few remaining coastal watersheds in central California
that can support steelhead runs. 70 Fed. Reg. 52,488, 52,507
(Sep. 2, 2005). In 2005, the NMFS designated AG Creek as
a critical habitat that remained “essential for conservation”
of the SCCC steelhead. Id. at 52,508. It has also continued
to reaffirm the creek’s ecological importance.
C.
Constructed in 1969, the Lopez Dam is located about
thirteen miles upstream from the mouth of AG Creek and is
operated by the County. Standing 160 feet tall and lacking
any fish passage infrastructure, the dam entirely blocks
steelhead from reaching the creek’s headwater tributaries.
Id. at 52,507–08. According to an NMFS report, these
upstream tributaries constitute approximately 64% of the
high-quality habitat that steelhead would otherwise use. The
NGOs’ expert ecologist, Tevin Schmitt, opines that the
migration cycle to and from the upper AG Creek habitat is
crucial for steelhead survival, but the dam prevents all
access.
Schmitt further contends that the County’s operation of
the dam has significantly degraded the remaining habitat
below the dam. Since 2007, the County has been operating
Lopez Dam according to its Interim Downstream Release
Schedule (“IDRS”). The IDRS does not provide a specific
numeric schedule for releases of water but plans releases
10 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
depending on hydrologic conditions and downstream
demands. The result, however, is a seasonal pattern in which
the County releases higher flows from July through
November—typically the driest months—and lower flows
from December through June, which coincides with the peak
steelhead migration and spawning season. On average, this
practice reduces downstream water flow by approximately
41%.
The NGOs argue that the IDRS eliminates the kind of
pulsing, high flows essential to triggering steelhead
migration and supporting the species’ life cycle. They
further claim that these altered flows raise water
temperatures in the lower creek, encouraging the presence of
warm-water predators that prey on juvenile steelhead.
Compounding the issue, according to the NGOs, is the
County’s failure to prevent predatory, non-native fish from
spilling over the dam into the creek below during reservoir
overflow events.
Finally, the NGOs contend that the County’s
construction and maintenance of road culverts and flood
control levees in AG Creek have further impeded the
steelhead’s migration. The levee system narrows what was
once a broad, dynamic floodplain, reducing the riparian
vegetation and habitat complexity steelhead rely on. The
culverts, meanwhile, often become clogged with debris,
creating additional barriers to upstream migration.
D.
Regulations enacted under to the ESA proscribe the
“take” of threatened steelhead DPS, including SCCC
steelhead. 16 U.S.C. § 1538(a)(1)(B); 50 C.F.R.
§ 223.203(a). The statute defines “take” broadly to include
conduct such as “to harass, harm, pursue, hunt, shoot,
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 11
wound, kill, trap, capture, or collect, or to attempt to engage
in any such conduct.” 16 U.S.C. § 1532(19).
The ESA provides some exceptions to its prohibition of
takes. Under section 10, an otherwise prohibited take by a
non-federal entity may be authorized by an incidental take
permit (“ITP”), “if such taking is incidental to, and not the
purpose of, the carrying out of an otherwise lawful activity.”
16 U.S.C. § 1539(a)(1)(B). Because the NMFS regulates
marine and anadromous fish, it handles any ITPs for take of
such species. To obtain such a permit, the applicant must
submit a habitat conservation plan (“HCP”), which must
specify “the impact which will likely result from such
taking;” “what steps the applicant will take to minimize and
mitigate such impacts, and the funding that will be available
to implement such steps;” “what alternative actions to such
taking the applicant considered and the reasons why such
alternatives are not being utilized;” and such other measures
that NMFS or the United States Fish and Wildlife Service
(“USFWS”) may require. 16 U.S.C. § 1539(a)(2)(A).
In 1999, prompted by the NMFS’s repeated warnings
that the County’s operation of Lopez Dam would require
ESA authorization, the County initiated environmental
impact studies. In 2004, it submitted to the NMFS its draft
HCP as a first step toward securing an ITP. In the HCP, the
County identified and estimated several ways in which the
dam’s operations harmed the steelhead. But the NMFS
found the HCP inadequate and that substantial revisions to
the proposed flow schedule were needed. Since then, despite
promptings from the NMFS, the County has yet to develop
another HCP and ITP application. The NGOs bring this suit
to force the County into compliance.
12 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
II. PROCEDURAL HISTORY
Shortly after filing, the NGOs moved for a mandatory
preliminary injunction. The NGOs contend that the
County’s operations are causing an unlawful take of the
SCCC steelhead in violation of ESA section 9 and are
separately violating California Fish & Game Code
(“CFGC”) section 5937 by failing to release sufficient water
to maintain the fish in “good condition.” The NGOs
requested that the district court order the County to take
certain actions, including, but not limited to, submitting and
implementing a proposed plan for releasing sufficient flows
from Lopez Dam into the lower AG Creek area. The NGOs
emphasized that preliminary relief was time-sensitive, as the
steelhead’s winter migration season—triggered by the first
substantial rains—could begin as early as November.
Both sides submitted extensive evidence, including
expert declarations addressing the dam’s effects on AG
Creek’s habitat and the steelhead. The County provided
additional evidence that the endangered tidewater goby and
threatened California red-legged frog are also known to
inhabit the AG Creek watershed. The tidewater goby
inhabits the lower creek area and the lagoon while the
California red-legged frog inhabits the AG Creek generally.
County expert Mark Jennings opined that the schedule of
pulse-flow and base-flow releases from the dam proposed by
the NGOs to help the steelhead would dislodge the tidewater
goby or red-legged frog nests or egg masses, resulting in a
take. The NGOs countered with a competing expert analysis
suggesting that increased flows would, in fact, improve
habitat conditions for both species by reducing the presence
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 13
of non-native predators and providing them necessary
water. 1
On November 27, 2024, the district court granted the
NGOs’ motion for a mandatory preliminary injunction in
part. On December 9, 2024, the district court issued a
preliminary injunction order that adopted most of the NGOs’
requested relief. The order requires extensive action by the
County, including to develop, implement, and study a flow
release plan, and set a base flow release schedule depending
on the amount of water in Lopez Reservoir; regularly
monitor and clear debris from culverts; develop and
implement a plan for installation of a fish screen across the
Lopez Dam; develop a plan for studying volitional steelhead
passage past Lopez Dam and implementing a feasible
alternative that is identified; and develop and submit an HCP
and an ITP application to the USFWS and NMFS on an
expedited timeline.
The preliminary injunction also instructs the County to
request input and guidance from the NMFS and USFWS in
implementing these measures. Consistent with those
requirements, the County submitted a proposed plan for flow
release to the NMFS and USFWS for their review and
comment. But on January 7 and 10, 2025, the County
received responses from the USFWS and NMFS,
respectively, declining to comment on any of “the various
interim measures specified in the Preliminary Injunction
Order.” Instead, the agencies recommended that the County
coordinate with them through the ITP process to develop an
1
Unrelated to threatened species, the County also presented declarations
from public agency officials who receive drinking water from operation
of Lopez Dam and Reservoir, discussing, among other things, adverse
consequences that would result from reduced water supply.
14 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
HCP to avoid, minimize, and mitigate potential impacts to
California red-legged frog and tidewater goby from Lopez
Dam management activities to ensure compliance with the
ESA.
III. STANDARD OF REVIEW
We have jurisdiction under 28 U.S.C. § 1331 and § 1367.
Our review of a district court’s grant of a preliminary
injunction is both limited and deferential. Flathead-Lolo-
Bitterroot Citizen Task Force v. Montana, 98 F.4th 1180,
1188 (9th Cir. 2024) (citing Sw. Voter Registration Educ.
Project v. Shelley, 344 F.3d 914, 918 (9th Cir. 2003) (en
banc)). The scope of our review is confined to “determining
whether the district court abused its discretion or based its
decision on an erroneous legal standard or clearly erroneous
findings of fact.” Burlington, 23 F.3d at 1510. A finding of
fact is clearly erroneous “if it is implausible in light of the
record, viewed in its entirety, or if the record contains no
evidence to support it.” Nat’l Wildlife Fed’n v. Nat’l Marine
Fisheries Serv., 422 F.3d 782, 794 (9th Cir. 2005) (“NWF
I”) (citation omitted).
This deference, however, is lessened when the
preliminary injunction is mandatory. A mandatory
preliminary injunction, unlike a prohibitory one, does not
serve to preserve the status quo pending resolution of the
merits but instead compels the nonmoving party to take
affirmative action. See Chalk v. U.S. Dist. Court, 840 F.2d
701, 704 (9th Cir. 1988); Garcia v. Google, Inc., 786 F.3d
733, 740 (9th Cir. 2015) (en banc). Such injunctions are
disfavored. Garcia, 786 F.3d at 740. Consequently, where
the injunction is mandatory, as is the case here, the relief “is
subject to heightened scrutiny and should not be issued
unless the facts and law clearly favor the moving party.”
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 15
Dahl v. HEM Pharms. Corp., 7 F.3d 1399, 1403 (9th Cir.
1993) (citing Anderson v. United States, 612 F.2d 1112,
1114 (9th Cir. 1980)); Garcia, 786 F.3d at 740.
IV. DISCUSSION
We grapple with two questions. First, how should the
district court weigh the interests of the California red-legged
frog and tidewater goby—both ESA-listed species. Second,
did the district court properly do so.
The County takes the view that, notwithstanding TVA,
the district court had to balance the equities and the public
interest because the injunction might affect the goby and the
frog. Not doing so, it argues, was a legal error warranting
reversal. And if such a balance must be struck, the County
adds, then it must consider all equities and all interests—not
just those of the protected species. The NGOs, on the other
hand, read TVA and its progeny as taking equitable balancing
off the table altogether in ESA cases, regardless of whether
other listed species might be implicated. But they also insist
that, regardless, the district court did consider the effect of
its order on the goby and frog and still thought an injunction
was warranted.
The County challenges the injunction under the NGOs’
CFGC section 5937 claim as well, arguing that the NGOs
failed to show a likelihood of success and irreparable harm.
And, like the ESA claim, the parties reprise their argument
over whether the court must balance the equities and public
interest under CFCG section 5937. 2
2
The County and the NGOs also disagree as to whether the preliminary
injunction was sufficiently narrowly tailored. Because we conclude that
16 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
A.
In Winter v. Natural Resources Defense Council, Inc.,
555 U.S. 7 (2008), the Supreme Court set out the familiar
four-factor test. A party is entitled to a preliminary
injunction if it demonstrates “(1) that it is likely to succeed
on the merits, (2) that it is likely to suffer irreparable harm
in the absence of preliminary relief, (3) that the balance of
equities tips in its favor, and (4) that an injunction is in the
public interest.” Flathead, 98 F.4th at 1190 (cleaned up).
But in ESA cases, there is an exception to the last two
factors, originating from the Supreme Court’s ruling in TVA.
In TVA, the Tennessee Valley Authority had nearly finished
building the Tellico Dam when biologists discovered that the
reservoir it would create would wipe out the only known
habitat of the snail darter, at the time thought to be a tiny
species of perch fish. 437 U.S. at 156–61. Soon after that
discovery, Congress enacted the ESA, and the Secretary of
the Interior listed the snail darter as endangered. Completion
of the dam, the Secretary concluded, would destroy the
species’ habitat. Id. at 160–62; 40 Fed. Reg. 47,505–06
(Oct. 9, 1975).
Environmental groups filed a lawsuit seeking to enjoin
completion of the dam and impoundment of the reservoir on
the ground that those actions would violate the ESA. TVA,
437 U.S. at 164–65. The district court agreed that the dam
would “result in the adverse modification, if not complete
destruction, of the snail darter’s critical habitat,’ making it
‘highly probable’ that ‘the continued existence of the snail
the district court erred in its assessment of the balance of equities and the
public interest for both the ESA and CFGC section 5937 claims, we do
not address the remaining arguments.
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 17
darter’ would be ‘jeopardize[d].’” Id. at 165–66 (alteration
in original) (footnote omitted). But it nonetheless denied the
request for a permanent injunction, explaining that the
project was nearly completed and “‘there [were] no
alternatives to impoundment of the reservoir, short of
scrapping the entire project.’” Id. at 166 (alteration in
original). The district court found that if the relief sought
were granted “[s]ome $53 million would be lost in
nonrecoverable obligations,” which Congress could not have
intended when it passed the ESA. Id. at 166–67 (alteration
in original).
The Supreme Court disagreed. Beginning with an
“examination of the language, history, and structure of the”
ESA, the Court found “beyond doubt that Congress intended
endangered species to be afforded the highest of priorities.”
Id. at 174. Tracing the evolution of legislative activity
leading up to the ESA and the various congressional debates
on the issues, the Supreme Court observed as to section 7
that the “pointed omission of the type of qualifying language
previously included in endangered species legislation
reveals a conscious decision by Congress to give endangered
species priority.” Id. at 185; see also id. at 188 (noting that
Congress did include some exceptions to the ESA’s sweep
in section 10, “meaning that under the maxim expressio
unius est exclusio alterius, we must presume that these were
the only ‘hardship cases’ Congress intended to exempt”). It
held that “[t]he plain intent of Congress in enacting this
statute was to halt and reverse the trend toward species
extinction, whatever the cost.” Id. at 184.
Concluding “that there [was] an irreconcilable conflict
between operation of the Tellico Dam and the explicit
provisions of” section 7, the Court turned to the question of
“what remedy, if any, is appropriate.” Id. at 193. The Court
18 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
held that because “Congress has spoken in the plainest of
words, making it abundantly clear that the balance has been
struck in favor of affording endangered species the highest
of priorities,” id. at 194, the district court’s denial of a
permanent injunction was reversible error, see id. at 168,
195.
Congress amended the ESA shortly after TVA was
decided. Those amendments “lightened the load” imposed
by the 1973 Act by moderating the ESA’s absolute
requirements. See Me. Lobstermen’s Ass’n v. Nat’l Marine
Fisheries Serv., 70 F.4th 582, 596 (D.C. Cir. 2023). The
amendments also created a new administrative
mechanism—the Endangered Species Committee,
sometimes called the “God Squad”—to grant exemptions in
exceptional cases. See Act of Nov. 10, 1978, Pub. L. No.
95-632, 92 Stat. 3751; Nat’l Ass’n of Home Builders v. Defs.
of Wildlife, 551 U.S. 644, 687 (2007) (Stevens, J.,
dissenting).
Despite Congress’s statutory change and the fact that
TVA specifically addressed the application of section 7, the
Ninth Circuit has expanded the rule of TVA—that courts
have no discretion to balance equities or the public interest
when considering whether a permanent injunction is
warranted under section 7—to the consideration of any
injunction, preliminary or permanent, sought in any ESA
case. For instance, in Flathead, we affirmed the district
court’s order granting a preliminary injunction to limit
Montana’s authorization of wolf trapping and snaring that
resulted in the unlawful taking of the threatened grizzly bear.
98 F.4th at 1184–85. We reiterated that when analyzing a
request for preliminary injunctive relief under the ESA,
“only the first two factors” of the Winter test “are at issue.”
Id. at 1190; see also Burlington, 23 F.3d at 1509, 1511
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 19
(describing that “[t]he ‘language, history, and structure’ of
the ESA demonstrates Congress’ determination that the
balance of hardships and the public interest tips heavily in
favor of protected species” when assessing an injunction
enjoining a railroad from striking the threatened grizzly
bears in Montana); NWF I, 422 F.3d at 793–94 (citing TVA
when assessing a preliminary injunction regarding the
management of dams in the Columbia River Basin and the
protection of the threatened steelhead); Cottonwood, 789
F.3d at 1090 (because Congress has “strip[ped] courts of at
least some of their equitable discretion in determining
whether injunctive relief is warranted,” “courts do not have
discretion to balance the parties’ competing interests in ESA
cases” (citing TVA, 437 U.S. at 185)).
B.
While our precedent holds that ESA cases depart from
the usual Winter framework, that does not settle the present
case. TVA and its progeny dealt with injunctions halting
disruptions to natural habitats—a quintessential conflict
caused by the “economic growth and development
untempered by adequate concern and conservation” that
Congress was specifically concerned about. 16 U.S.C.
§ 1531(a)(1). In this context, courts do not consider the
balance of the equities and the public interest, because
Congress already did so in deciding that endangered species
would take precedence “whatever the cost.” TVA, 437 U.S.
at 184.
This rationale, however, collapses where protecting one
listed species might jeopardize another—as here. This
conflict is not merely between unchecked development and
conservation. It is additionally between the interests of
multiple protected species. The injunction at issue seeks to
20 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
protect the SCCC steelhead. But evidence presented to the
district court also shows that the injunction could harm the
California red-legged frog and the tidewater goby, both of
which are also entitled to ESA protection. The question that
TVA answered—whether a court can displace Congress’s
intent that “endangered species [are] to be afforded the
highest of priorities,” id. at 174—is therefore not dispositive.
Rigidly applying TVA in this context risks turning the
ESA on its head. The first two Winter factors—the only ones
left under TVA—look solely to the plaintiff’s likelihood of
success of showing an unlawful take and the irreparable
harm to the species the plaintiff has sued to protect. Nothing
in that inquiry leaves room to account for the frog or goby.
The ESA’s command to prioritize endangered species
becomes a one-way ratchet, favoring one listed species
without any room to weigh the cost to another.
And the tension is even sharper here because the
injunction was mandatory, not prohibitory. Ordering a party
to stop harmful conduct is one thing; compelling it to act
affirmatively in a way that could harm other species is
another. Without equitable discretion, a court could end up
ordering relief that saves one species at the expense of
another.
Accordingly, we hold that district courts retain their
equitable discretion when considering a mandatory
preliminary injunction under the ESA that could endanger
other listed species. The exception to the traditional test,
created in TVA, does not apply. The court must balance the
equities and consider the public interest as to the other listed
species.
That does not mean, however, that the door is open to
every and all interests and equities. We reject the County’s
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 21
position that this holding resurrects all the usual equities—
economic, developmental, or otherwise. Congress was clear
that endangered species come first, “whatever the cost.” Id.
at 184. So the only equities that matter here are those related
to the interest of other ESA-listed species.
To be clear, our holding does not require a district court
to deny relief whenever another species might be affected.
Habitats are complex. Species are interconnected.
Sometimes, what looks harmful to one species in the short
term may benefit it, or others, in the long run. And if there
is no way to reconcile the risks to multiple listed species, the
equities and public interest in species conservation, to which
the ESA gave precedence, do not counsel a single outcome
and judgments may need to be made about the relative
strength of these considerations in relation to the protected
species at issue. If courts had to reject an injunction every
time a defendant could point to another at-risk species, the
ESA’s protections would become hollow in these
circumstances. We leave it to the district courts to assess
whether a mandatory preliminary injunction for the
protection of one species is appropriate despite the risks to
others. See Weinberger v. Romero-Barcelo, 456 U.S. 305,
312 (1982) (“[T]he essence of equity jurisdiction has been
the power of the Chancellor to do equity and to mould each
decree to the necessities of the particular case. Flexibility
rather than rigidity has distinguished it.” (internal quotation
marks omitted) (quoting Hecht Co. v. Bowles, 321 U.S. 321,
329 (1944))). But our decision requires that district courts
weigh the risks and benefits to all ESA-listed species in play
and then decide whether an injunction is warranted.
22 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
C.
Despite the district court’s best efforts, the frog and goby
received no meaningful consideration. Implicitly
recognizing the illogical result of applying TVA to the facts
of this case, the district court attempted to bridge the gap by
directing the parties to consult with federal agencies to
ensure the goby and frog would not be harmed. But
attempting to involve the appropriate federal agencies is not
an adequate substitute for the exercise of informed
discretion, as the record here highlights. The NMFS and
USFWS declined to weigh in, instead directing the County
to pursue the formal HCP and ITP processes. But those
processes can take months or years, and the critical wet
season is fast approaching.
As the NGOs point out, the district court dedicated a
portion of its order to describing the evidence concerning the
creatures. It did not, however, proceed to weigh the balance
of equities or the public interest before granting injunctive
relief. The district court summarized the evidence presented
by both sides regarding the California red-legged frog and
the tidewater goby, but it drew no conclusions about how
that evidence should factor into its decision.
For instance, the district court observed that the County’s
proffered expert,
Dr. Jennings[,] claims that [the NGOs’]
proposed flow schedule would harm the
tidewater goby, because “any large
rainstorms” during the tidewater goby’s
breeding season along with the increased
downstream flows would sweep out the
juvenile and adult gobies. In response, [the
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 23
NGOs’] expert, Tevin Schmitt, disagrees
with Dr. Jennings’ conclusion and suggests
that the proposed flow release schedule
“includes an adequate adaptive management
process” that could adjust the flows and avoid
any harm to the other species.
But rather than weigh the evidence, the court instead directed
the parties to work with the agencies to implement the
injunction in a way that protected all species. The district
court’s analysis, therefore, does not satisfy the mandatory
preliminary injunction standard.
On remand, the district court must weigh the evidence on
all affected species. The district court may decide that some
or all of the prior measures should be reinstated. For
example, the County pointed only to the flow-related
provisions as potentially harmful to the frog and goby. It is
possible that other aspects of the injunction may also be
reinstated. But that decision must be made by the district
court in the first instance. See Singleton v. Wulff, 428 U.S.
106, 120 (1976).
D.
We turn now to the NGOs’ request for injunctive relief
pursuant to CFGC section 5937. The district court found
that the text of the statute does not answer the question of
whether CFGC section 5937 prioritizes the preservation of
fish above other competing water uses. It therefore weighed
all the factors under Winter and held that they favored the
NGOs. We agree with the district court’s application of the
full Winter test to the NGOs’ state law claim. But, for
reasons we’ve already explained in the ESA context, the
24 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
court’s actual analysis of the equities and the public interest
fell short.
We start with why the ESA exception does not apply to
the NGOs’ claim under CFGC section 5937. That exception
derives from TVA, which rested on Congress’s unmistakable
command that endangered species be given “the highest of
priorities.” 437 U.S. at 174. That congressional judgment
obviously does not extend to a California statute. And the
caselaw the NGOs rely on does not fill the gap. In California
Trout, Inc. v. Superior Court, 218 Cal. App. 3d 187 (1990)
(“Cal. Trout II”), the state court explained that “the
Legislature has already balanced the competing claims for
water . . . and determined to give priority to the preservation
of their fisheries.” See 218 Cal. App. 3d at 201. But that
statement was about CFGC section 5946, not section 5937.
And CFGC section 5946 incorporates section 5937—not the
other way around. The state court’s interpretation of CFGC
section 5946 cannot be mapped onto section 5937 based on
the California Trout cases. Indeed, the state court has “not
explicitly [held] that § 5937 mandates placing the
preservation of fish above the irrigation purposes of a dam,
but reserves the question of the statute’s application alone as
a rule affecting appropriation of water, separate
from § 5946.” Nat. Res. Def. Council v. Patterson, 333 F.
Supp. 2d 906, 920 (E.D. Cal. 2004) (“Patterson II”) (citing
Cal. Trout, Inc. v. State Water Res. Control Bd., 207 Cal.
App. 3d 585 (1989) (“Cal. Trout I”)).
But while the district court was correct in applying the
full Winter test, its analysis was incomplete. The district
court found that the County’s evidence of concerns about the
water supply for residential, agricultural, and municipal
purposes does not outweigh the other interests at stake. Yet
it never spelled out what those other interests or equities are.
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 25
Presumably, it had in mind the same considerations it
discussed under the ESA. But, as we discussed, that ESA
analysis was insufficient. The district court did not explain
which evidence it found more persuasive or how the equities
and public interest ultimately came out. Therefore, like the
ESA claim, the district court’s CFGC section 5937 analysis
remains unfinished. We vacate the preliminary injunction
on this claim as well.
V. CONCLUSION
We hold today that when a district court considers a
mandatory preliminary injunction under the ESA and the
evidence shows that other listed species may also be
affected, the TVA exception to the Winter test does not apply.
In that circumstance, the court must weigh the balance of
equities and the public interest solely as they bear on those
other species. Because the district court here did not do so,
we vacate the preliminary injunction and remand for further
proceedings consistent with this opinion.3
VACATED AND REMANDED.
3
The NGOs’ request for judicial notice at Docket Entry 33 is denied as
moot and the request at Docket Entry 68 is stricken as improper
supplemental briefing. The NGOs’ request for judicial notice at Docket
Entry 63 is granted.
26 SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO
VANDYKE, Circuit Judge, concurring:
I join the majority opinion in full. I write separately to
emphasize the demanding standard that must be met before
a district court may issue a mandatory preliminary
injunction, a standard that becomes even harder to satisfy in
cases like this one which involve the complicated interplay
between different species.
In general, district courts should hesitate before granting
requests for mandatory preliminary injunctions. Because
mandatory preliminary injunctions disrupt the status quo
before any party has definitively proven its case, our
precedent repeatedly calls such injunctions “disfavored” and
applies “a higher degree of scrutiny” to them, denying
requests for mandatory preliminary injunctions unless the
facts and law clearly favor the requesting party. Stanley v.
Univ. of S. Cal., 13 F.3d 1313, 1320 (9th Cir. 1994) (quoting
Anderson v. United States, 612 F.2d 1112, 1114 (9th Cir.
1980)); Edmo v. Corizon, Inc., 935 F.3d 757, 784 n.13 (9th
Cir. 2019). This means that mandatory preliminary
injunction requests “are not issued in doubtful cases.”
Marlyn Nutraceuticals, Inc. v. Mucos Pharma GmbH & Co.,
571 F.3d 873, 879 (9th Cir. 2009) (quoting Anderson, 612
F.2d at 1115).
Applying that rigorous standard in the Endangered
Species Act context means that district courts must be
confident that the relief granted will not adversely affect
other species before pulling the trigger on a mandatory
preliminary injunction. Reaching such a conclusion with
confidence is very challenging at the preliminary injunction
stage in cases like this one. The County’s expert noted that
steelhead likely prey on red-legged frog tadpoles and are
known to eat the tidewater goby. See also Endangered
SAN LUIS OBISPO COASTKEEPER V. COUNTY OF SAN LUIS OBISPO 27
Species Facts: Tidewater Goby, U.S. EPA,
https://www.epa.gov/system/files/documents/2025-
05/tidewater-goby.pdf (last visited Oct. 31, 2025). This
evinces that injunction requested in this case may be a zero-
sum game: an injunction that helps the steelhead inherently
risks harming the goby and the frog. Add to this the fact that
the South-Central California Coast steelhead at issue in this
case is merely a “threatened” species, while the goby has the
more serious “endangered” listing. 71 Fed. Reg. 834, 857
(Jan. 5, 2006); 59 Fed. Reg. 5494, 5495 (Feb. 4, 1994). In
circumstances like these, proving that “the facts and law
clearly favor” the party requesting a mandatory preliminary
injunction is a difficult endeavor—as it should be. Stanley,
13 F.3d at 1320 (quoting Anderson, 612 F.2d at 1114).
Because I don’t understand the majority opinion to be
inconsistent with that understanding, I am pleased to join it.
Plain English Summary
FOR PUBLICATION UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT SAN LUIS OBISPO No.
Key Points
01FOR PUBLICATION UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT SAN LUIS OBISPO No.
02FORESTWATCH; CALIFORNIA 2:24-cv-06854- COASTKEEPER ALLIANCE; SPG-AS ECOLOGICAL RIGHTS FOUNDATION, OPINION Plaintiffs - Appellees, v.
03COUNTY OF SAN LUIS OBISPO Opinion by Judge Nguyen; Concurrence by Judge VanDyke SUMMARY * Endangered Species Act The panel vacated the district court’s mandatory preliminary injunction requiring the County of San Luis Obispo to take certain
04The NGOs contend that the County’s operations are causing an unlawful take of the steelhead in violation of section 9 of the Endangered Species Act (“ESA”) and are separately violating California Fish & Game Code (“CFGC”) section 5937 by fa
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FOR PUBLICATION UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT SAN LUIS OBISPO No.
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