Many recent decisions by the Ninth Circuit have required the court to review agency actions under the Administrative Procedure Act (APA) arbitrary or capricious standard. The Supreme Court has held that the arbitrary or capricious standard is a “highly deferential” standard of review, though the inquiry must nonetheless “be searching and careful.” Furthermore, the agency’s decision is “‘entitled to a presumption of regularity,’ and [the Court] may not substitute [its] judgment for that of the agency.” For purposes of this discussion, it is important to note that “traditional deference to the agency is at its highest where a court is reviewing an agency action that required a high level of technical expertise.”
In cases where a petitioner is challenging an agency action under the Endangered Species Act (ESA) the court will usually be tasked with reviewing whether the action was arbitrary or capricious in light of the ESA’s “best available science” mandate. The ESA requires an agency to insure that its actions will not jeopardize the continued existence of any endangered species, and the best available science mandate requires the agency to utilize the best available scientific data to inform its no jeopardy review. Challenges to an agency action as arbitrary and capricious for failing to utilize the best available science must show that the agency ignored the relevant available science.
Given the heightened level of deference for decisions based on science and the low standard of what constitutes the best available science, the ESA mandate rarely threatens to invalidate an agency’s decision. In fact, none of the Ninth Circuit cases in the last year that have considered the issue have substantively evaluated an agency decision under the best available science mandate. Rather, the agencies were given heightened deference to make their own decisions as to what constituted best available science. This leaves us to wonder whether the ESA’s best available science mandate serves as a purposeful requirement in the Ninth Circuit.
II. The APA and the Arbitrary and Capricious Standard
The APA provides the standard for judicial review of an agency decision. Specifically, section 10 addresses judicial review and provides:
To the extent necessary to decision and when presented, the reviewing court shall decide all relevant questions of law, interpret constitutional and statutory provisions, and determine the meaning or applicability of the terms of an agency action.
Section 10 further establishes the arbitrary and capricious standard by stating that the reviewing court shall “hold unlawful and set aside agency action, findings, and conclusions found to be … arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law.”
The APA’s arbitrary and capricious standard of review, however, is only applied when the governing legislation does not set forth its own standard of review. There are several examples of legislation that utilize the APA as a default, but key to this commentary is the fact that the ESA also relies on the APA as its default standard of review.
A. Meaning of Arbitrary and Capricious
Based on the text of the applicable legislation, it is easy to know when the arbitrary and capricious standard will be applied as the governing standard of review. However, in addition to understanding when the standard of review will be applied, it is helpful for both agencies and courts to have the same understanding of what is meant by “arbitrary and capricious.”
Congress did not define precisely what it meant by “arbitrary and capricious” within the text of the APA. Instead, courts have looked to the terms’ ordinary meaning for a definition. For example, Black’s Law defines arbitrary as a decision “founded on prejudice or preference rather than on reason or fact.” Additionally, capricious is defined as “unpredictable or impulsive behavior” or “contrary to the evidence or established rules of law.”
The arbitrary and capricious standard of review is a very narrow standard of review that requires the reviewing court to assume a deferential posture such that the court may not simply substitute its judgment for that of the agency. Although the court’s deference must be at its highest when reviewing agency decisions relying on technical expertise, the reviewing court still has an affirmative obligation under the APA to ensure the agency exercised sound judgment and made a reasonable decision based on its available information. Thus, in its review the court must walk a fine line between substituting its judgment for that of the agency and simply affirming agency decision making because it was the decision of the agency.
The U.S. Supreme Court has somewhat defined this line by stating that courts are only to determine if the agency considered the “relevant factors” and if the agency made a “clear error of judgment,” rendering its actions arbitrary and capricious. Because terms such as “clear error of judgment” do not provide a clear standard, the Supreme Court articulated four specific scenarios for when agencies’ actions are considered arbitrary and capricious:
- The agency “relied on factors which Congress has not intended it to consider.”
- The agency “entirely failed to consider an important aspect of the problem.”
- The agency “offered an explanation for its decision that runs counter to the evidence before the agency.”
- The agency offered an explanation “so implausible that it could not be ascribed to a difference in view or the product of agency expertise.”
These rules provide clarity to both courts and agencies because they set forth a specific standard for determining whether an agency has acted arbitrarily and capriciously.
III. Best Available Science Under the Endangered Species Act
The Endangered Species Preservation Act of 1966 (ESPA) was the first environmental statute to impose a requirement to utilize science in environmental decisions made by an administrative body. The statute required the Secretary of the Interior to make determinations as to which species were at risk of extinction and directed the secretary to consult with relevant scientists in creating the list of endangered species. The ESPA did not require the ultimate listing decisions to rest on the scientific information, but Congress intended the consultations to provide the foundation for the listings.
The “best available science” requirement was later introduced in the Endangered Species Conservation Act of 1969 and remained largely unchanged in the current ESA. However, Congress neither defined “best available science” nor provided instruction as to how to apply the requirement in either the 1969 Act or the current 1973 Act. It has been suggested that the term “best available science” was not further defined in either the 1969 or 1973 statutes because Congress simply intended to continue the ESPA requirement to seek input from scientists prior to making listing decisions.
B. What is Required Under the Best Available Science Mandate?
Without an explicit statutory definition or guidelines of how to apply the best available science mandate, we are forced to rely on judicial opinions interpreting the ESA to ascertain what is required by the mandate. Two distinct guidelines emerge from looking at these opinions: (1) an agency cannot ignore relevant available data and (2) an agency does not have an obligation to generate new data, even if only relatively weak data is available.
The Ninth Circuit has repeatedly held that an agency “cannot ignore available biological information.” Put more specifically, the agency “must not disregard available scientific evidence that is in some way better than the evidence it relies on.” Furthermore, the court has held that an agency is not necessarily in noncompliance with the best available science mandate if it disagrees with or discredits the available scientific data. For example, in Kern County Farm Bureau v. Allen (Kern) the court rejected Kern’s argument that the United States Fish & Wildlife Service (FWS) violated the best available science mandate by misinterpreting three studies. In Kern, the fact that the FWS cited the studies and did not ignore them was enough to comply with the best available science mandate. Therefore, a challenger must specifically point to relevant data that was omitted from consideration to sustain a claim that an agency failed to utilize the best available science.
Although the Ninth Circuit has required an agency to utilize the best scientific data available, the court has also held that the mandate “does not… require an agency to conduct new tests or make decisions on data that does not yet exist.” This holding is consistent with other circuits that have addressed this issue. For example, the D.C. Circuit has held that an agency must utilize the best scientific data available, not the best scientific data possible.
This approach has been met with criticism because agencies are allowed to rely on data that is weak or inconclusive when it is the only data available. Because few data are available for many endangered species, there exists the possibility that many decisions regarding endangered species will be made with little to no scientific data in support. If that were the case, the purpose of consulting scientific data prior to making a decision would be entirely undermined.
C. Application of the Best Available Science Mandate Under the Current Endangered Species Act
The best available science mandate is triggered any time an agency contemplates an action that might impact an endangered species. Section 7(a) of the ESA requires the agency to “insure that any action authorized, funded, or carried out by such agency is not likely to jeopardize the continued existence of any endangered or threatened species or result in destruction or adverse modification of the habitat of such species.” Section 7(a) further requires that in fulfilling the requirements under the section the agency “shall use the best available scientific and commercial data.”
The deference afforded to agencies in review of science-based decisions raises doubt as to whether the best available science mandate actually operates as a substantial requirement to an agency proposing an action under section 7. The Ninth Circuit in particular has held that when the analysis of an agency decision requires a high level of technical expertise, the court “must defer to the informed discretion of the responsible federal agencies.” In fact, it is common practice across the circuits to give an “extreme degree” of deference to decisions founded on the scientific or technical expertise of an agency.
IV. Ninth Circuit Deference on Matters of Science
A. A Substantive Mandate in 2005
In 2005 the Ninth Circuit decided Pacific Coast Federation of Fishermen’s Ass’ns v. Bureau of Reclamation (Pacific Coast) and breathed life into the best available science mandate. Prior to this decision, many courts had used deference to avoid upholding the substantive mandate requiring agencies to insure against jeopardy. In Pacific Coast, the Ninth Circuit inserted itself into the Klamath Basin conflict. The conflict stemmed from the National Marine Fisheries Service (NMFS) issuing a biological opinion (BiOp) requiring the Bureau of Reclamation (BOR) to limit diversion of water from the Klamath River for irrigation purposes because this diversion would jeopardize the continued existence of the endangered suckerfish and coho salmon. This closure resulted in significant agricultural losses, as 2001 also saw record drought.
After the drought of 2001, the Departments of the Interior and Commerce commissioned the National Research Council (NRC) to perform a “scientifically rigorous peer review” of whether the BiOp was consistent with available scientific information. The conclusion of the NRC study questioned the validity of the 2001 BiOp. The study found that “the 2001 BiOp’s drastic halting of water diversions was not scientifically supported,” but the study did not offer comment as to the minimum water levels necessary to maintain the endangered fish.
In 2002, BOR prepared a long-range biological assessment and proposed a new flow regime that would vary the river flow by “water year type.” The NMFS concluded that the BOR’s proposed actions would jeopardize the continued existence of coho salmon, and it issued a new BiOp that developed a reasonable and prudent alternative (RPA) to replace the BOR proposal. That RPA was the subject of Pacific Coast.
The Northern District of California found that the short-term measures of the RPA were not arbitrary and capricious. On appeal to the Ninth Circuit, the Court did not grant the customary heightened deference to the agency’s decision. Rather, the Court engaged in a “careful and searching” review of the BiOp, stating that the agency “is obligated to articulate a rational connection between the facts found and the choices made.” Specifically, the court found that
Although . . . the agency believed that the RPA would avoid jeopardy to the coho, this assertion alone is insufficient to sustain the BiOp and the RPA. The agency essentially asks that we take its word that the species will be protected if its plans were followed. If this were sufficient, the NMFS could simply assert that its decisions were protective and so withstand all scrutiny.
Therefore, the Ninth Circuit found the authorized short-term measures of the Bi-Op to be arbitrary and capricious.
This decision marked an important step in making the ESA’s best available science requirement a substantive mandate. Despite the deference due to the agency, the court looked substantively at the BiOp to find that it could not insure against jeopardy. This case sent a message that an agency could not rely on heightened deference to avoid judicial review of its actions.
B. Clarification of the Arbitrary and Capricious Standard in 2008
In 2008, the Ninth Circuit sought to “clarify some of [its] environmental jurisprudence” by hearing en banc Lands Council v. McNair (Lands Council III). The court felt a need for uniformity because Ecology Center, Inc. v. Austin “defied well-established law concerning the deference [the court] owe[s] to agencies and their methodological choices.” Additionally, the court likely wanted to address the fact that “in recent years, [the Ninth Circuit’s] environmental jurisprudence has, at times, shifted away from the appropriate standard of review and could be read to suggest” that judges should sit on the bench and “act as a panel of scientists.”
The en banc review resulted in a reversal of the preliminary injunction initially granted by the Ninth Circuit in The Lands Council v. McNair (Lands Council II) and the overruling of Ecology Center. Lands Council III overruled Ecology Center’s instruction that courts may suggest how an agency is required to validate its scientific methodology. In Ecology Center, the court required the Forest Service to “demonstrate the reliability of its scientific methodology or the hypothesis underlying the Service’s methodology with on the ground analysis,” but the court in Lands Council III concluded that the Forest Service may use a particular analysis “if it deems it appropriate or necessary, but it is not required to do so.” In other words, as long as “there is a reasonable scientific basis to uphold the legitimacy of [the] modeling,” the courts are required to give deference to the agency and uphold its model. Therefore, Lands Council III significantly reigned in the court’s ability to question how agencies justify scientific methodology.
In addition to precluding courts from prescribing the means by which an agency validates its scientific methodologies, Lands Council III also established that courts do not have the authority to choose which scientific studies support agency actions. If the agency considered the scientific evidence available to it, courts must defer to the agency’s interpretations of that scientific evidence.Therefore, because the Forest Service considered many different studies, the court in Lands Council III explicitly deferred to the agency’s interpretation of the scientific evidence.
Finally, Lands Council III overruled Ecology Center’s requirement that an agency must present every scientific uncertainty in the evidence used to inform a decision. Consequently, an agency no longer bears “the burden to anticipate questions that are not necessary to its analysis, or to respond to uncertainties that are not reasonably supported by any scientific authority.” The Ninth Circuit only requires that an agency “acknowledge and respond to comments by outside parties that raise significant scientific uncertainties and reasonably support that such uncertainties exist.”
Thus, the en banc court established three rules to guide Ninth Circuit jurisprudence when using the arbitrary and capricious standard of review for an agency’s use of science:
- Courts may not prescribe the specific means by which an agency must validate methodologies.
- Courts may no longer choose between which scientific studies support an agency’s action, so long as the agency provides an explanation for its conclusion.
- An agency no longer needs to address every scientific uncertainty surrounding the science it uses to support its position. The agency only needs to “acknowledge” and “respond” to the claims by parties raising and supporting that “significant scientific uncertainties” exist.
C. Current Cases
Pacific Coast marked what commentators believed was a change toward a more substantive science requirement. However, a decade later it does not appear as though the Ninth Circuit has continued down the Pacific Coast path of reducing the deference it affords to agencies when reviewing compliance with the best available science mandate. Rather, the Ninth Circuit has stayed consistent with the “rules” issued by the Lands Council III en banc court. However, the three cases decided by the Ninth Circuit in 2015 reviewing the best available science requirement under the ESA show that heightened agency deference is rendering the science mandate utterly meaningless.
In Alliance for the Wild Rockies v. Bradford, the Ninth Circuit issued a memorandum opinion affirming that the United States Forest Service (USFS) did not violate the ESA by concluding that its Grizzly Project would not likely adversely affect the grizzly bear population. The court noted that USFS met the requirements of the ESA by consulting the Wakkinen Study when making its determination. The court also noted that its review of the scientific judgments and technical analyses made within an agency’s field of expertise should be at its most deferential. Therefore, the court concluded that USFS had complied with the ESA’s best available science mandate.
In Center for Biological Diversity v. United States Fish & Wildlife Service, the Center for Biological Diversity (CBD) brought suit against the FWS challenging the FWS’s decision to sign a memorandum of agreement (MOA) for groundwater pumping based on conclusions reached in its biological opinion (BiOp). CBD sued for declaratory and injunctive relief against the FWS alleging, among other things, that the BiOp failed to meet the best available science standard set forth by §7 of the ESA.
Specifically, CBD argued that the foundation of the BiOp’s no jeopardy finding was based on expediency not on science. CBD attempted to support its argument by pointing to the fact that the conservation measures’ flow reduction triggers were negotiated and not biologically based. The Ninth Circuit noted that the ESA does not require FWS to design or plan its projects using the best science possible. Rather, “once action is submitted for formal consultation, the consulting agency must use the best scientific and commercial evidence available in analyzing the potential effects of that action on endangered species in its biological opinion.” Therefore, the court concluded that negotiated terms do not of themselves prove that the BiOp analysis failed to utilize the best available science.
Additionally, CBD argued that the BiOp’s conclusions should not be given deference because the FWS failed to address concerns raised by its own scientists regarding the effectiveness of the MOA’s conservation measures. The Ninth Circuit explained that CBD’s claim failed as there was no evidence supporting a conclusion that FWS scientists’ concerns were supported by better science than the science used in the BiOp, or that FWS disregarded better scientific information than the evidence FWS relied upon. Thus, the Ninth Circuit concluded that CBD was unable to prove that the no jeopardy conclusion in the BiOp was arbitrary or capricious for failing to utilize the best available science.
In Cascadia Wildlands v. Thrailkill, Cascadia Wildlands (Cascadia) brought action seeking to enjoin the Douglas Fire Complex Recovery Project (Recovery Project), which authorized salvage logging of roughly 1,600 acres of fire-damaged forest. In approving the Recovery Project, the Medford District of the Bureau of Land Management relied on a biological opinion issued by the FWS. This biological opinion concluded that the Recovery Project was not likely to result in jeopardy to the Northern Spotted Owl species or in destruction or adverse modification of the critical habitat. Cascadia claimed the FWS biological opinion failed to comply with requirements of the ESA because the FWS did not apply scientific data to the opinion.
As to the no jeopardy conclusion, the court found that the record supported that the FWS relied on several surveys to reach its conclusion and gave the agency deference that the data it used was the best available scientific data. With regard to the effects on the habitat, the court found that the FWS utilized several lengthy scientific reports regarding pre-fire and post-fire habitats to support the conclusion in its biological opinion. Furthermore, the court noted that a reviewing court cannot substitute its judgment for that of the agency when the agency used adequate and reliable data.
Cascadia also argued that the FWS’s 2011 Northern Spotted Owl Recovery Plan constituted the best available science and that the FWS was required to follow it. The court rejected this argument. The court stated that recovery and jeopardy are two distinct concepts. The court noted that a Recovery Project does not necessarily need to promote or bring about a long-term recovery of the species. Rather, the biological opinion should and does focus on the Recovery Project’s ability to conserve the habitat so as not to have a detrimental effect on the species population.
The court ultimately concluded that Cascadia failed to show that the FWS did not utilize the best available scientific information when issuing its biological opinion that the Recovery Project would not jeopardize the Northern Spotted Owl or its critical habitat. Therefore, the Ninth Circuit affirmed the district court’s denial of the preliminary injunction to enjoin the Recovery Project.
These three cases illustrate that the Ninth Circuit is still affording agencies heightened deference in scientific judgments and technical analyses. The court appears to look merely at whether the agency consulted scientific data prior to making decisions without reviewing the adequacy of the scientific data. Therefore, the ESA’s best available science mandate can be easily satisfied and will be subject to little scrutiny in the Ninth Circuit.
When reviewing scientific decisions based on agency expertise, the standard practice across the circuits is to afford deference to the agency unless is it shown that the agency ignored relevant scientific data when making its decision. Unfortunately, this practice leaves little recourse for petitioners seeking to hold an agency accountable for substantiating its decision. As it stands now, the best available science requirement is satisfied as long as the agency considers the available data. The agency is free to disagree with the data, discredit the data, or rely on weak or inconclusive data if it is the only data available. As long as the agency articulates the rationale between the data and the decision made, the court will uphold the agency action. This means that as long as an agency communicates a justification for its decision, the justification itself will more than likely not be reviewed by the court.
In 2005, the Ninth Circuit substantively reviewed an agency decision and found the agency relied heavily on unstated assumptions rather than scientific evidence. Had the court simply given deference to the agency’s conclusion because it articulated a justification for its decision, the court would have failed to notice that the agency was not actually basing that decision on science. Pacific Coast exemplifies the need for substantive review of agency decisions, even though the court does not like to assume the role of technical expert.
Although the Ninth Circuit demonstrated in Pacific Coast that it was willing to substantively review agency decisions relating to science, the court has since shifted back to the more customary deferential approach. As the three 2015 cases show, the Ninth Circuit is reluctant to substitute its judgment for that of an agency with regard to science and as a result affords agencies great deference when reviewing decisions based on the agency’s scientific expertise.
It is unclear why the Ninth Circuit has shifted back to the deferential standard of review. Perhaps it is because Congress has remained silent on the science standard for over three decades, or perhaps the court is reluctant to proceed differently than the other circuits. Whatever the reason, it is clear that until courts engage in substantive review of agencies’ scientific decisions or Congress establishes an explicit standard of the type and quality of scientific data required, the best science available mandate will continue to operate as a fiction in the review of agency decisions.
* J.D. Candidate 2017, Lewis & Clark Law School. Please send correspondence to firstname.lastname@example.org.
 E.g., Cascadia Wildlands v. Thrailkill, 806 F.3d 1234 (9th Cir. 2015); Ctr. for Biological Diversity v. U.S. Fish & Wildlife Serv., 807 F.3d 1031 (9th Cir. 2015); All. for the Wild Rockies v. Bradford, 601 Fed. App’x 488 (9th Cir. 2015) (mem.).
 Administrative Procedure Act, 5 U.S.C. §§ 551–559, 701–706, 1305, 3105, 3344, 4301, 5335, 5372, 7521 (2012).
 5 U.S.C. § 706(2)(A) (requiring a reviewing court to uphold agency action unless it is “arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law.”).
 Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 378 (1989); San Luis & Delta-Mendota Water Auth. v. Jewell, 47 F.3d 581 (9th Cir. 2014).
 Jewell, 47 F.3d at 601. (quoting Citizens to Preserve Overton Park, Inc. v. Volpe, 401 U.S. 402, 415–16 (1971)).
 Marsh, 490 U.S. at 377.
 Endangered Species Act of 1973, 16 U.S.C. §§ 1531–1544 (2012).
 See cases cited supra note 2.
 16 U.S.C. § 1536(a)(2) (2012).
 See Bldg. Indus. Ass’n of Superior Cal. v. Norton, 247 F.3d 1241, 1246 (D.C. Cir. 2001).
 Katherine Renshaw, Leaving the Fox to Guard the Henhouse: Bringing Accountability to Consultation Under the Endangered Species Act, 32 Colum. J. Envtl. L. 161, 187 (2007).
 See cases cited supra note 2.
 See cases cited supra note 2.
 5 U.S.C. § 706 (2012).
 E.g., Al-Fayed v. Cent. Intelligence Agency, 254 F.3d 300, 304 (D.C. Cir. 2001) (“The APA, however, ‘provides a default standard of judicial review . . . where a statute does not otherwise provide a standard.’”).
 The National Forest Management Act (NFMA), 16 U.S.C. §§1600–1687 (2012), and the National Environmental Policy Act of 1969 (NEPA), 42 U.S.C. §§ 4321–4370h (2012), are other examples of legislation that rely on the APA as a default standard of review.
 See 5 U.S.C. §706(2)(A) (2012).
 See Fed. Commc’ns Comm’n v. Fox Television Stations, Inc., 556 U.S. 502, 516 (2009) (stating that the arbitrary and capricious standard is satisfied so long as the Commission’s action was not arbitrary or capricious in the ordinary sense); United States v. Locke, 471 U.S. 84, 95 (1985) (deference to the supremacy of the Legislature, as well as recognition that Congressmen typically vote on the language of a bill, generally requires us to assume that the legislative purpose is expressed by the ordinary meaning of the words used).
 Black’s Law Dictionary 112 (9th ed. 2009).
 Id. at 224.
 Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 377–78 (1989); see U.S. Postal Service v. Gregory, 534 U.S. 1, 6–7 (2001).
 See Marsh, 490 U.S. at 377–78.
 Motor Vehicle Mfrs. Ass’n of U.S., Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43 (1983).
 Pub. L. No. 89-669, 80 Stat. 926 (1966).
 Holly Doremus, Listing Decisions Under the Endangered Species Act, Why Better Science Isn’t Always Better Policy, 75 Wash. U.L.Q. 1029, 1042 (1997).
 § 1(c), 80 Stat. at 926.
 Doremus, supra note 15, at 1042.
 Pub. L. No. 91-135, 83 Stat. 275 (1969).
 See 16 U.S.C. § 1536(a)(2) (2012).
 See § 3(a), 83 Stat. at 275; 16 U.S.C. § 1532 (2012).
 Doremus, supra note 15, at 1043.
 Renshaw, supra note 12, at 167.
 Conner v. Burford, 848 F.2d 1441, 1454 (9th Cir. 1988); see also San Luis & Delta-Mendota Water Auth. v. Locke, 776 F.3d 971, 995 (9th Cir. 2014).
 San Luis & Delta-Mendota Water Auth., 776 F.3d at 995.
 See id.
 450 F.3d 1072 (9th Cir. 2006).
 Id. at 1081.
 See id.
 San Luis & Delta-Mendota Water Auth., 776 F.3d at 995.
 E.g., Am. Wildlands v. Kempthorne, 530 F.3d 991, 998–99 (D.C. Cir. 2008).
 Bldg. Indus. Ass’n of Superior Cal. v. Norton, 247 F.3d 1241, 1246 (D.C. Cir. 2001).
 Renshaw, supra note 12, at 169.
 16 U.S.C. § 1536(a)(2) (2012).
 Selkirk Conservation All. v. Fosgren, 336 F.3d 944, 954 (9th Cir. 2003).
 City of Waukesha v. U.S. Envtl. Prot. Agency, 320 F.3d 228, 247 (D.C. Cir. 2003); see also Maine v. Norton, 257 F. Supp. 2d at 389 (“The court must defer to the agency’s expertise, particularly with respect to decision-making which involves a high level of technical expertise.”); A.M.L. Int’l, Inc. v. Daley, 107 F. Supp. 2d 90, 102 (D. Mass. 2000) (“Indeed, a reviewing court must afford special deference to an agency’s scientific expertise.”).
 426 F.3d 1082 (9th Cir. 2005).
 Renshaw, supra note 12, at 187.
 See Pacific Coast, 426 F.3d 1082.
 See id. at 1087.
 See id.
 J.B. Ruhl, The Battle Over Endangered Species Act Methodology, 34 Envtl. L. 555, 584–85 (2004).
 Pacific Coast, 426 F.3d at 1087.
 Renshaw, supra note 12, at 188.
 Pacific Coast, 426 F.3d at 1088.
 Id. at 1089.
 See id.
 Id. at 1091.
 Id. at 1092.
 537 F.3d 981, 984 (9th Cir. 2008).
 430 F.3d 1057 (9th Cir. 2005).
 Lands Council III, 537 F.3d at 991.
 Id. at 998.
 494 F.3d 771 (9th Cir. 2007), rev’d en banc, 537 F.3d 981 (9th Cir. 2008).
 Lands Council III, 537 F.3d 990–94.
 Id. at 990.
 Ecology Center, 430 F.3d at 1064.
 Lands Council III, 537 F.3d 991–92.
 Id. at 992.
 Id. at 994–95.
 Id. at 995.
 Id. at 996.
 Lands Council III, 537 F.3d at 1001.
 Id. at 992–94, 1001 ; see also Ryan G. Welding & Michael E. Patterson, Maintaining the Ninth Circuit’s Clarified Arbitrary and Capricious Standard of Review for Agency Science After Lands Council v. McNair, 31 Pub. Land & Resources L. Rev. 55, 79–80 (2010).
 See Renshaw, supra note 12.
 See cases cited supra note 2.
 601 Fed App’x 488 (9th Cir. 2015).
 Id. at 490.
 Id. (“The Forest Service relied on the Wakkinen Study, which is the best available science, and the Fish & Wildlife Service concurred in the Forest Service’s determination.”).
 807 F.3d 1031 (9th Cir. 2015).
 Id. at 1035.
 Id. at 1048.
 Id. at 1049–50.
 Id. at 1049–51.
 806 F.3d 1234 (9th Cir. 2015).
 Id. at 1235–36.
 Id. at 1236.
 Id. at 1238–41.
 Id. at 1241–42.
 Id. at 1242.
 Id. at 1243.
 Id. at 1243–44.
 Id. at 1244.
 See cases cited supra note 50.
 See Conner v. Burford, 848 F.2d 1441, 1454 (9th Cir.1988); see also San Luis & Delta-Mendota Water Auth. v. Locke, 776 F.3d 971, 995 (9th Cir. 2014).
 See, e.g., San Luis & Delta-Mendota Water Auth., 776 F.3d at 995.
 Ctr. for Biological Diversity v. U.S. Fish & Wildlife Serv., 807 F.3d 1031, 1043 (9th Cir. 2015).
 See Pacific Coast, 426 F.3d 1082.
 See Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 377 (1989.