Citations
- 244 F. Supp. 3d 66
Full opinion text
MEMORANDUM OPINION
RANDOLPH D. MOSS, United States District Judge
Blueback herring (alosa aestivalis) are silver-colored fish, roughly a foot in length, that inhabit much of North America’s Atlantic coast. The species is “anadromous,” meaning the fish are born in inland rivers, then spend most of their adult lives at sea, while still returning to their natal rivers for six to eight weeks each spring to spawn.
In 2011, the Natural Resources Defense Council (“NRDC”) petitioned the National Marine Fisheries Service (“Service”) to list blueback herring as “threatened” under the Endangered Species Act of 1973. The Service undertook a lengthy review in response, but ultimately found that listing the species “[wa]s not warranted.” See Endangered Species Act Listing Determination for Alewife and Blueback Herring, 78 Fed. Reg. 48,944 (Aug. 12, 2013) (“Listing Decision”). The NRDC and others now challenge that determination. Because the Court agrees that the Service failed to offer a rational connection between the facts and two of its essential conclusions, and because the Service entirely failed to consider other important aspects of the problem, the Court will VACATE the Listing Decision and will REMAND the matter to the Service for further proceedings consistent with this opinion.
I. BACKGROUND
A. The Endangered Species Act
The Endangered Species Act exists to conserve endangered and threatened species and “the ecosystems upon which [they] depend.” 16 U.S.C. § 1531(b). As amended, the Act defines “species” to include not just “any subspecies of fish or wildlife,” but also any “distinct population segment” of any species of vertebrate fish or wildlife which interbreeds when mature. Id. § 1532(16). A species is “endangered” if it “is in danger of extinction” either throughout “all ... of its range” or throughout “a significant portion of its range.” Id. § 1532(6). And a species is “threatened” if it “is likely to become ... endangered ... within the foreseeable future” throughout “all or a significant portion of its range.” Id. § 1532(20) (emphasis added).
The Act directs the Service, along with its counterpart in the Department of the Interior, to “determine whether any species is ... endangered ... or ... threatened,” id. § 1533(a), and to publish lists of species designated as such, id. § 1533(c)(1). Listed species then receive heightened protections under the Act. See generally id. §§ 1533-1538. Any “interested person” may petition the Service to change a species’s status, see 5 U.S.C. § 553(e); 16 U.S.C. § 1533(b)(3); 50 C.F.R. § 424.14, and, if the petition “presents substantial scientific or commercial information indicating that the petitioned action may be warranted,” the Service must “promptly” conduct a species status review, 16 U.S.C. § 1533(b)(3)(A). The Service must then publish its findings in a listing determination, id., which must rest on any one or a combination of - the following factors:
(A) the present or threatened destruction, modification, or curtailment of [the species’s] habitat or range;
(B) overutilization for commercial, recreational, scientific, or educational purposes;
(C) disease or predation;
(D) the inadequacy of existing regulatory mechanisms; or
(E) other natural or manmade factors affecting [the species’s] continued existence.
16 U.S.C. § 1533(a)(1); see also 50 C.F.R. § 424.11(c). In addition, the Service must make its listing determination “solely on the basis of the best scientific and commercial data available.” 16 U.S.C. § 1533(b)(1)(A).
B. Factual Background
Blueback herring “use many different habits” throughout their life cycle, “including the ocean, estuaries, rivers, and freshwater lakes and ponds.” Listing Decision, 78 Fed. Reg. at 48,945. They spend the first few months of their life in freshwa-ters. They then migrate to the open sea, where they mature and spend most of their adult life (in what is called their “ocean phase”), before returning “to estuarine and freshwater rivers, ponds, and lake habitats to spawn.” Id.; see also Dkt. 40-1 at 104-06 (AR 2048-50) (describing blue-back herring lifecycle). Adult blueback herring “frequently return[ ] to their natal rivers for spawning,” but may, on occasion, “stray[ ] ... between rivers.” Listing Decision, 778 Fed. Reg. at 48,945. Evidence also suggests, but has not conclusively determined, that blueback herring migrate large distances even during their ocean phase, moving en masse with the seasons up and down the Atlantic coast. See, e.g., id. at 48,949-50; Dkt. 40-5 at 146 (AR 66,934). The species’s range reaches south to the St. John’s River in Florida, north to the Miramichi River in New Brunswick, Canada, and east into oceanic waters along the continental shelf. Listing Decision, 78 Fed. Reg. at 48,945, 48,948.
Figure 1: Approximate Blueback Herring Range in U.S. Waters (2007)
In August 2011, the NRDC petitioned the Service to list blueback herring as “threatened.” See Dkt. 40-1 at 86-192 (AR 2030-136) (Petition). Citing numerous studies, the NRDC argued that blueback herring had “suffered dramatic population declines” from their nineteenth-century peak and that those declines had continued over the past four decades. Id. at 87, 110 (AR 2031, 2054). The causes, the NRDC argued, were primarily “fishing-related mortality, dams, dredging and blasting, water pollution, and global warming.” Id. at 88-89 (AR 2032-33). The Service deemed the petition supported by substantial scientific evidence, see 90-Day Finding on a Petition To List Alewife and Blueback Herring as Threatened Under the Endangered Species Act, 76 Fed. Reg. 67,652, 67,656 (Nov. 2, 2011), and, pursuant to its statutory mandate, embarked on a blue-back herring status review.
As a launching point for its analysis, the Service relied on the May 2012 River Herring Benchmark Stock Assessment prepared by the Atlantic States Marine Fisheries Commission (“ASMFC”). Listing Decision, 78 Fed. Reg. at 48,944. The ASMFC study analyzed data from 52 in-river United States “stocks,” i.e., .discrete “part[s] of a fish population” with “particular migration pattern[s]” and “specific spawning grounds.” Dkt. 40-3 at 146, 151 (AR 52,745, 52,750). Of those 52 stocks, 22 displayed evidence of declining rivér herring populations, 1 displayed evidence of an increasing population, and the remaining 28 lacked data to support definitive quantitative conclusions about population trends. Id. at 151 (AR 52,750). On the whole, the ASMFC determined that “[t]he coastwide meta-complex of river herring stocks on the US Atlantic coast is depleted to near historic lows.” Id.
The Service also “worked cooperatively with [the] ASMFC” to “identify information not in the stock assessment that [would be] needed for [the] listing determination.” Listing Decision, 78 Fed. Reg. at 48,944. At the outset of the status review, they convened three sets of workshops and working groups with experts in the field. Listing Decision, 78 Fed. Reg. at 48,944; see Dkt. 40-1 at 11 (AR 1). Two of those working group reports received peer review from the Center for Independent Experts. Listing Decision, 78 Fed. Reg. at 48,944.
C. The Listing Decision
On August 12, 2013, the Service published its fifty-page Listing Decision “deter-minfing] that listing blueback herring as threatened or endangered” was “not warranted at th[at] time.” Listing Decision, 78 Fed. Reg. at 48,944. The decision turned on three central conclusions. First, the Service found that it lacked sufficient data to deem any subset of blueback hérring a “distinct population segment.” Id. at 48,950, 48,993. Second, “as a result of [its] extinction risk analysis,” the Service determined that the blueback herring “[was] not in danger of extinction [throughout all of its range] or likely to become so in the foreseeable future.” Id. at 48,993. And, third, without addressing whether the blueback herring was threatened or endangered throughout the “Mid-Atlantic” region, the Service concluded that the Mid-Atlantic region was “not ... a significant portion of the blueback herring’s range.” Id.
The grounds for those conclusions appear to have been as follows.
1.The Service’s “Distinct Population Segment” (“DPS”) Analysis
The Service first sought to identify any “distinct population segments” of blueback herring. Because the Act’s definition of “species” includes “distinct population segment[s]” of any species of vertebrate fish, 16 U.S.C. § 1532(16), each “distinct population segment” of blueback herring requires its own status determination. The threshold issue for'the Service, therefore, was delineating exactly which “species” were the subjects of its review. See Listing Decision, 78 Fed. Reg. at 48,948-50.
a. The 1996 DPS Policy
To make this threshold determination, the Service applied its Policy Regarding the Recognition of Distinct Vertebrate Population Segments Under the Endangered Species Act, 61 Fed. Reg. 4722 (Feb. 7, 1996) (the “1996 DPS Policy”). Under the 1996 DPS Policy, a group of animals of the same taxon (ie., biological species) is a “distinct population segment” only if two conditions are met. First, the group must be “discrete[ ].” Id. at 4725. A group is discrete under the 1996 DPS Policy if it is either (1) “markedly separated from other populations of the same taxon as a consequence of physical, physiological, ecological, or behavior factors” or (2) “delimited by international governmental boundaries” across which meaningfully different regulatory mechanisms exist. Id. Second, the group must be “significant] ... to the [taxon] to which it belongs.” Id. Under the 1996 DPS Policy, “significance” depends on factors that “may include”—but are “not limited to”—the following:
1. Persistence of the discrete population segment in an ecological setting unusual or unique for the taxon,
2. Evidence that loss of the discrete population segment would result in a significant gap in the range of a tax-on,
3. Evidence that the discrete population segment represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historic range, or
4. Evidence that the discrete population segment differs markedly from other populations of the species in its genetic characteristics.
Id. “Because precise circumstances are likely to vary considerably from case to case,” the policy adds, “it is not possible to describe prospectively all the classes of information that might bear on the biological and ecological importance of a discrete population segment.” Id.
b. The Five “Discrete” Population Segments
The Service’s “discreteness” finding turned largely on genetics research by Dr. Eric P. Palkovacs. Listing Decision, 78 Fed. Reg. at 48,948-49; see also Dkt. 40-6 at 233-47 (AR 73,485-99) (Palkovacs et al. report to the “stock structure” working group). Dr. Palkovacs collected DNA samples from 1,183 blueback herring across 20 rivers in the United States and performed statistical analyses to test them for genetic differentiation. Listing Decision, 78 Fed. Reg. at 48,948-49; Dkt. 40-6 at 234-35 (AR 73,486-87). He noted, however, that the “neutral genetic markers” he tracked (ie., the DNA sequences he compared across specimens) “represented] the effects of gene flow and historical population isolation, but [did] not [represent] the effects of adaptive processes.” Listing Decision, 78 Fed. Reg. at 48,949.
The Palkovaes analysis revealed a minimum of four geographic “clusters” of rivers in the United States, within which blueback herring populations were “genetically homogenous,” Dkt. 40-6 at 235 (AR 73,487), and between which blueback herring populations were “genetically distinguishable,” id. at 233 (AR 73,485). See also Listing Decision, 78 Fed. Reg. at 48,948-49. These clusters also corresponded to “larger-scale geographic boundaries,” across which “gene flow [was] extremely minimal.” Dkt. 40-6 at 237 (AR 73,489). Dr. Palkovaes therefore concluded that these geographic boundaries “define[d] the higher-level population structure” for blue-back herring in the United States. Id. The four Palkovaes “stock complexes” were the “Northern New England,” “Southern New England,” “Mid-Atlantic,” and “Southern” stock complexes, Listing Decision, 78 Fed. Reg. at 48,949 (citing Dkt. 40-6 at 238 (AR 73,490)), as shown in the figure below.
Figure 2: Blueback Herring U.S. Stock Structure as Defined by Palkovaes et al.
Applying the 1996 DPS Policy, the Service determined that the four stock complexes identified by Dr. Palkovacs represented “discrete” population segments. Id. at 48,950. This conclusion presumably relied on the policy’s first discreteness prong, which looks for populations “markedly separated from otherfs] ... as a consequence of physical, physiological, ecological, or behavior factors,” 1996 DPS Policy, 61 Fed. Reg. at 4725—factors that include the genetic and geographic evidence that Dr. Palkovacs examined.
Notably, the Palkovacs analysis did not consider the entire blueback herring population: it omitted (1) blueback herring in Canadian rivers and (2) blueback herring in their “ocean phase,” where all blueback herring (regardless of stock) spend most of their adult lives. The Service resolved the issue regarding Canadian blueback herring by designating them as a fifth “discrete” population segment—not based on genetic differentiation, but based on the second prong of the “discreteness” test, which keys to “international governmental boundaries.” Id. at 48,950 (applying 1996 DPS Policy, 61 Fed. Reg. at 4725). The oceanic population, however, proved more difficult. For that group, the Service found that “[migration and mixing patterns of ... blueback herring in the ocean ha[d] not been determined,” id. at 48,949, but that experts suspected the oceanic population to be “comprised of mixed stocks,” id. at 48,950. Given the anticipated level of mixing, the Service decided that “the ocean phase” of blueback herring could not be treated as its own discrete population segment “until further tagging and genetic data become available.” Id. at 48,949.
The Service, accordingly, settled on five “discrete” blueback herring population segments, which the Listing Decision and this opinion refer to—from north to south—as the (1) Canadian, (2) Northern New England, (3) Southern New England, (4) Mid-Atlantic, and (5) Southern stock complexes. Id. at 48,949-50. Although blueback herring spend the majority of their adult lives in the ocean, see id, at 48,945, the Service could not conclude that the oceanic population segment was “discrete,” id. at 48,949-50. All of these population segments corresponded to geographic areas, as depicted (roughly) in the map below.
Figure 3: The Five “Discrete” In-River Stock Complexes and the “Mixed” (Non-Discrete) Oceanic Population
c. No “Significant” Population Segments
Despite finding these five stock complexes to be “discrete,” the Service concluded that none of them met any of the 1996 DPS Policy’s four (non-exclusive) criteria for “significance.” See Listing Decision, 78 Fed. Reg. at 48,950. As an initial matter, the Listing Decision stated that the Service “considered all [four] of the [1996 DPS Policy’s] criteria” and observed that blueback herring “occupy many different ecological settings throughout their range.” Id. It then devoted several paragraphs to the second and fourth criteria for “significance” under the policy.
As to the second criterion—whether “the loss of [a] discrete population segment” would create a “significant gap” in the remaining population’s range, id. at 48,948—the Service acknowledged that “the loss of [any one] stock complex would mean the loss of [the corresponding] sub-populations” of herring that were born in and annually return to those rivers, id. at 48,950. But, because the oceanic population is “comprised of mixed stocks,” the Service reasoned, the oceanic territory “would most likely still be occupied by migratory river herring from other stock complexes.” Id. The Service thus concluded:
As it has been shown that gene flow is greater among neighboring runs than among distant runs, we might expect that river herring would re-colonize neighboring systems- over a relatively short time frame. Thus, the loss of one stock complex in itself may not be significant; the loss of contiguous stock complexes may be. The goal then for river herring stock complexes is to maintain connectivity between genetic groups to support proper metapopulation function (spatially separated populations of the same species that interact, reeolonize vacant habitats, and occupy new habitats through dispersal mechanisms).
Id.
As to the fourth criterion—-whether any “discrete population segment differs markedly ... in its genetic characteristics”— the Service sought to distinguish its earlier finding under the discreteness prong that the four Palkovacs stock, complexes were “markedly separated from other population segments” as a result of their genetic characteristics. See supra Part I.C.l.b, To do so, the Service seized on Dr. Palko-vacs’s “caveat” that the genetic markers his study looked for “represented the effects of gene flow and historical population isolation, but not the effects of adaptive processes.” Id. at 48,949. As the Service explained, “[n]eutral genetic markers ... have a longstanding history of utilization in stock designation for many anadromous fish species.” Id. at 48,950. “[T]hese markers,” however, “represent the effects* of gene flow and historic population isolation and not the effects of adaptive behavior.” Id. That information, the Service concluded, is “appropriately used in support of the discreteness criterion.” Id. But because “neutral markers” of the kind Dr. Palko-vacs measured do not “capture! ]” “[t]he effects of adaptive genetic and phenotypic diversity,” they have no bearing on the significance determination. Id.
Based on this analysis, the Service declined to designate any “distinct population segments” of blueback herring. See id. “The [four Palkovacs] stock complexes may be discrete,” the Service wrote, “but under the DPS policy, they are not significant.” Id. The Service further concluded that, “given the unknown level of intermixing between Canadian and U.S. river herring in coastal waters, the Canadian stock complex should also not be considered separately under the DPS policy.” Id.
2'. The Service’s Extinction Risk Analysis
Having determined that the only “species” at issue was the entire taxon of blue-back herring, the Service turned to its main inquiry: Are blueback herring “threatened”—i.e., “likely to become [in danger of .extinction] in the foreseeable future” throughout “all ... of their range”? 16 U.S.C. § 1532(20). This extinction risk analysis' contained both a qualitative and a quantitative component, although it is unclear whether and how the qualitative component impacted the decision not to list the species,
a. The Qualitative Rankings
In the qualitative component, the Service first surveyed the threats to blueback herring and categorized them under the five factors enumerated in 16 U.S.C. § 1533(a)(1). See Listing Decision, 78 Fed. Reg. at 48,953-70. This part of the Listing Decision merely catalogued potential threats to blueback herring, without analyzing the magnitudes of those threats or the likelihood that they would cause extinction. See id. Instead, the Service promised after each section that “the level of threat posed by these potential stressors [would be] evaluated further in the qualitative threats assessment below,” Id. at 48,958; accord id. at 48,961, 48,963, 48,968, 48,970.
.In the “qualitative threats assessment” itself, the Service asked nine of its team members to rank each potential threat on a scale from zero to five, according to perceived severity. Id, at 48,970. For example, if a team member considered a threat to be of “low” severity, she would assign it a “one;” if she considered it to be of “high” severity, she would assign' it a “five.” Id. After tabulating the results, the Service determined that its team believed “dams and other barriers” to be the most serious threats. See id. at 48,978. Although this “qualitative analysis” occupied thirty-two of the Listing Decision’s fifty pages, it nowhere discussed, analyzed, or drew conclusions regarding whether these or any other threats posed a risk of extinction to the blueback herring.
b. The Quantitative Models
The driver of the Service’s extinction risk conclusion—and, indeed, of the entire Listing Decision—appears to have been the ’Service’s quantitative “trend analysis modeling.” See Listing Decision, 78 Fed. Reg. at 48,985-92. This analysis began from the premise that, as of 1976, the blueback herring population had already undergone a significant decline. See id. at 48,987 (asserting that the risk analysis “assume[d] that there has already been a significant decline in abundance” due to overfishing); id. at 48,989 (stating that, “[p]rior to 1976, fishing intensity was much greater”); id. at 48,987 (explaining that the Service “use[d] data frbm 1976 through the present” to minimize the influence of the pre-1976 overfishing). “[G]iven the extensive declines from historical levels,” the Service wrote, the blueback herring “is [not] thought to be capable of withstanding continued high rates of decline.” Id. at 48,992. The Service thus sought to answer the following question: Since 1976, has the blueback herring population stabilized or has it continued to decline?
To explore this question, the Service retained Dr. Kiersten Curti of the Northeast Fisheries Science Center (“NEFSC”), and asked her to créate a number of statistical models to estimate the average annual change in the relative size of each blueback herring population segment—a metric the Service calls “relative abundance.” Listing Decision, 78 Fed. Reg. at 48,989; see also Dkt. 40-2 at 71-113 (AR 2477-519) (Dr. Curti’s report). The analysis involved the following steps,
i. The Models’ Design
Because Plaintiffs do not challenge the design of the models themselves, see, e.g., Dkt. 53 at 16, most of the technical details underlying those .models are not material to this opinion. For present purposes, the following simplified account will suffice.
As input, each- model took some number of time series, ie., lists of-values recorded for a given measurement each year. For example, some time series tracked the number of blueback herring that passed by a given monitoring site during certain observational periods each year. See Dkt. 47-1 at 5 (Damon-Randall Deck ¶ 6(b)) (describing “run counts”). Other time series tracked the total'biomass of blueback herring caught in a given river each year, divided by the total number of nets used. See id. (Damon-Randall Decl. ¶ 6(c)) (describing “catch per unit effort”). Time series like these are valuable because they theoretically correlate with the size of the regional blueback herring population—in other words, they are “indices of relative abundance.” But, because they measured different types of data, often with units of different dimensions {e.g., “físh per season” or “weight per net”), they were not always directly comparable. So, whenever a model took more than one time series as an input, Dr. Curtí multiplied each subsequent time series by whatever number was necessary to “scale[ ]” it to the same size as the first. Dkt. 40-2 at 75 (AR 2481). In other words, the time series within each model were “normalized” to a common scale. Dkt. 53 at 53.
As output, each model then generated an estimate of the average change per year in the modeled population’s “relative abundance.” Exactly what this number represents is unclear; neither the Service’s Listing Decision nor its submissions in this case have explained the units in which relative abundance was measured. As far as the Court can tell, relative abundance is measured in arbitrary “relative abundance” units, which do not directly represent any tangible values (unlike, say, “fish per year” or “biomass per net per year”). Instead, the “relative abundance” metric relays information only about the modeled population’s relative change in size. See, e.g., Dkt. 40-6 at 104 (AR 68,439) (explaining that “[the] modeling will give us percent decline over the time period modeled [but] not actual numbers”). So, for example, if the modeled population had 10 “relative abundance” units in 1980, and 15 “relative abundance” units in 1990, then the relative abundance grew by 5 units in 10 years, and the model’s output would be “0.5.” See Dkt. 53 at 51-54 (Oral Arg. Tr.). The models also paired each estimate with its 95% confidence interval and standard error. See Dkt. 40-2 at 77, 79 (AR 2483, 2485).
ii. The Models’ Inputs and Results
The Service originally intended that Dr. Curtí would create a total of six models: one model for each of the five “discrete” stock complexes (ie., the Canadian, Northern New England, Southern New England, Mid-Atlantic, and Southern' stock complexes), and one “coastwide” model that would incorporate data from the ocean near the Atlantic coast. See, e.g., Dkt. 40-2 at 72 (AR 2,478); Dkt. 40-6 at 204-05 (AR 68,929-30). Although the Listing Decision sometimes referred to the “coastwide” model as the “rangewide” model, that is a misnomer. Because the data in that model came only from the ocean—and not the species’s entire range, which would include inland rivers—it is best thought of as a proxy for the blueback herring’s “ocean phase,” where herring from all stock complexes mix together.
The Service was unable to obtain data from the Canadian government for the Canadian stock complex model and, therefore, did not construct a model for the population in Canadian rivers. See Listing Decision, 78 Fed. Reg. at 48,989 (“No blueback herring abundance indices were available for the Canadian stock.”); id. at 48,992 (“[W]e were unable to obtain data from Canada to determine the population growth rate for rivers in Canada.”). For the “coastwide” model, the Service used two sets of annual “trawl net” surveys from ships sailing along the coast. Id. at 48,988-89. And for the other four stock-specific models, the Service used data from the 2012 ASMFC stock assessment. Id. at 48,989. Each time series in that dataset was specific to a particular river or bay within a state or the District of Columbia. Most of the models used only one or two time series as inputs. The Mid-Atlantic model, however, used twelve. See Dkt. 40-2 at 84 (AR 2490) (list of stock-specific inputs). It is unsurprising, then, that the Mid-Atlantic model had the lowest margin of error of any of the models by an order of magnitude. See Listing Decision, 78 Fed. Reg. at 48,991.
The figures below describe the models’ numerical results:
Table 1: The Models’ Inputs and Outputs
[Editor’s Note: The preceding image contains the reference for footnote
Figure 4: Estimates and 95% Confidence Intervals for Each Population’s Average Annual Change in Relative Abundance
The Court notes, however, that while the time series were normalized within each model, the Court has not located an explicit statement in the record stating that the time series were also normalized across the five models. See, e.g., Dkt. 40-2 at 75 (AR 2481). In other words, it is not obvious that a “0.05” decrease in one model is equivalent to a “0.05” decrease in another.
iii. The Service’s Interpretation of the Models
In order to translate the models’ results into a concrete determination of blueback herring extinction risk, the Service employed a three-step process of its own design, which does not appear to have been the subject of any expert peer review.
In the first step, the Service assigned each modeled population one of three possible labels: “significantly increasing,” “significantly decreasing,” or “stable,” Listing Decision, 78 Fed. Reg. at 48,987. A modeled population was labeled “significantly increasing” if both ends of the confidence interval around the model’s estimate were positive. Id. Conversely, a modeled population was deemed “significantly decreasing” if both ends of the confidence interval were negative. Id. And, if a confidence interval began at a negative number and ended at a positive number (ie., if it included zero), the Service considered that modeled population “stable.” Id. As the Service explained:
Relative abundance of a stock is considered to be significantly increasing or decreasing if the 95-percent confidence intervals of the population growth rate do not- include zero. In contrast; if the 95-percent confidence intervals do contain zero, then the population is considered to be stable, as the increasing or decreasing trend in abundance is not statistically significant.
MThe Service, accordingly, assigned labels to the modeled populations as follows:
Table 2: Trend Labels
Because each trend label represented only a single blueback herring population segment, however, the Service needed a further mechanism to assess the risk of extinction rangewide. To do so, the Service created and applied two independent assessments, which it labeled “Tier A” and “Tier B.” See id. at 48,986-87. Although the Service designed each tier to assess different types of conservation metrics, see id., given the “significant uncertainties associated with the available data” and the “significant number of data deficiencies,” the Service decided after reviewing the models’ results that “it was not necessary to have information under both tiers in order to make a risk determination.” Id. at 48,986.
“The goal of Tier A,” the Service wrote, “was to maintain three contiguous stock complexes that are stable or increasing.” Id. As the results described above show, however, just two adjacent stock complexes—the Northern and Southern New England stock complexes—received the designation “stable.” The only other “stable” complex—the Southern stock complex— was separated from the others by the “significantly decreasing” Mid-Atlantic stock complex. And the last stock complex— Canada—received no label due to insufficient data. Thus, although the models failed to identify “three contiguous stock complexes” where the blueback herring population was “stable or increasing,” the Service concluded that it was unable to draw any results under Tier A because it lacked 'sufficient data regarding “the population growth rate for rivers in Canada.” Listing Decision, 78 Fed. Reg. at 48,992. Without that data, the Service wrote, “there [was] insufficient information available to make a conclusion under Tier A.” Id.
The Service’s decision whether to list blueback herring as threatened throughout its range, accordingly, came down to Tier B. The Service designed Tier B to “directly interpret the results” of its trend analysis models. Listing Decision, 78 Fed. Reg. at 48,986-87. Unlike “Tier A,” “Tier B” did not consider the stock complexes’ geographic arrangement; it looked only at how many of the modeled populations were “stable” or “significantly increasing.” Id. at 48,987. According to the Service:
[A] stable or significantly increasing trajectory suggests that [the blueback herring] may be within the margins of being self-sustainable .... [But] [a] significantly decreasing population growth rate for several stock complexes[, on the other hand,] would be an indicator that the current abundance may not be sustainable relative to current management measures and, therefore, may warrant further protections.
Id. The Service further stated that the level of extinction risk for blueback herring was a function of two criteria: (1) the number of stock-specific models that were “significantly decreasing;” and (2) whether or not the “coastwide” model was “significantly decreasing.” See id. The following matrix summarizes how the Service used these two criteria to determine the species-wide extinction risk:
Table 3: Tier B Outcome Matrix
Thus, because only one stock complex—the Mid-Atlantic—was “significantly decreasing,” and because the “coast-wide trajectory” and three of the four stock complexes were “stable,” the Service concluded that the blueback herring was at a “moderate low” risk of extinction through all of its range. See id. at 48,992. The Service therefore “determined that, as a result of the extinction risk analysis,” the blueback herring was “not in danger of extinction or likely to become so in the foreseeable future,” and that “listing ... blueback herring as either endangered or threatened throughout all of [its] range[ ] [wa]s not warranted at th[at] time.” Listing Decision, 78 Fed. Reg. at 48,993.
3. The Service’s “Significant Portion of its Range” (“SPR”) Analysis
The Service then turned to the last of its three central questions: Is the blueback herring threatened throughout a “significant portion of its range”? See 16 U.S.C. § 1532(20). For this purpose, the Service took the candidate “portions of [the] range” to be the geographic boundaries of the five discrete stock complexes which the Service had previously identified (but not the ocean-phase population, which is comprised of mixed stock). See Listing Decision, 78 Fed. Reg. at 48,993; see also supra Figure 3 (map of discrete stock complexes). To decide whether any of these stock complexes were “significant,” the Service applied its Draft Policy on Interpretation of the Phrase “Significant Portion of Its Range” in the Endangered Species Act’s Definition of “Endangered Species” and “Threatened Species,” 76 Fed. Reg. 76,987 (Dec. 9, 2011) (the “2011 Draft SPR Policy”).
Under the 2011 Draft SPR Policy, “if a species is found to be endangered or threatened in only a significant portion of its range, the entire species is listed as endangered or threatened, respectively, and the Act’s protections applies across the species’s entire range.” Id. at 76,990 (emphasis added). The Service therefore adopted an interpretation of “significant” that used “the species itself as the reference point.” Id. at 76,993. That interpretation is as follows:
Significant: A portion.of the range of a species is “significant” if its contribution to the viability of the species is so important that without that portion, the species would be in danger of extinction.
Id. at 77,002.
The Service’s subsequent application of the 2011 Draft SPR Policy to the blueback herring was brief. It concluded, in three sentences, that the risk of blueback herring extinction throughout the Mid-Atlantic region was immaterial because that portion of the range was not “significant.” It determined that the Mid-Atlantic region was not “significant” because, even assuming the hypothetical loss of that portion of the range, “the overall coastwide trend is stable.” Id. at 48,993. In other words, because “the relative abundance of the species throughout its range (as demonstrated through the coast-wide population growth rate) [wa]s stable,” the Service reasoned, “the [M]id-Atlantic stock complex does not contribute so much to the species that without it, the entire species would be in danger of extinction.” Id. at 48,992. The Service did not explicitly analyze the significance of any other regions. See id. at 48,992-93.
D. The Present Proceeding
Plaintiffs are five non-profit organizations with interests in the continued existence of blueback herring. They are the NRDC, the Anglers Conservation Network, the Delaware River Shad Fishermen’s Association, the Great Egg Harbor River Council, and the Great Egg Harbor Watershed Association. Dkt. 1 at 4-6 (Compl. ¶¶ 10-14). Invoking the Act’s “citizen -suit” provision, see 16 U.S.C. § 1540(g), they ask the Court to declare the Listing Decision unlawful, vacate it, and remand it to- the Service, see Dkt. 1 at 3-4 (Compl. ¶¶ 5, 7); Dkt. 27-3 at 54. Both ■sides have moved.for summary judgment. Dkts. 26 & 29. The Court has also received an amicus brief, Dkt. 36, Plaintiffs’ response to that brief, Dkt. 38, both parties’ postroral argument briefs, Dkts. 48 & 50, and various notices of supplemental authority, Dkts. 41-46, 51-52.
II. ANALYSIS ,
Plaintiffs challenge all three of the Listing Decision’s central conclusions, which the Court will address in the following order: First, did the Service reasonably conclude -that the Mid-Atlantic region is not a “significant portion” of the blueback herring’s range? Second, did the Service reasonably conclude that blueback herring are not threatened throughout all their entire range? And, third, did the Service reasonably conclude that the Mid-Atlantic stock complex of blueback herring is not a “distinct population segment”?
In considering each of these contentions, the Court must be mindful of both the bounds and demands of judicial review of administrative action. On the one hand, it is not the Court’s role to substitute its judgment for that of agency, and this, rule applies with particular force in a case, like this one, involving scientific analysis and “technical expertise.” Marsh v. Or. Nat. Res. Council, 490 U.S. 360, 377, 109 S.Ct. 1851, 104 L.Ed.2d 377 (1989); see also Balt. Gas & Elec. Co. v. NRDC, 462 U.S. 87, 103, 103 S.Ct. 2246, 76 L.Ed.2d 437 (1983) (“When examining this kind of scientific determination, ... a reviewing court must generally be at its most deferential.”). .“When specialists express conflicting views,” for example, “an agency must have discretion to rely on the reasonable opinions of its own qualified experts even if, as an original matter, a court might find contrary views more persuasive.” Marsh, 490 U.S. at 378, 109 S.Ct. 1851; see also, e.g., Defs. of Wildlife v. Zinke, 849 F.3d 1077, 1090 (D.C. Cir. 2017) (“[Competing views about scientific data and policy choices ... fail to show that the Service’s conclusions were arbitrary and capricious or contrary to law.”). Nor is an agency required to explain its conclusions with crystal clarity; rather, the Administrative Procedure Act (“APA”) merely requires that the reviewing court be able “reasonably [to] discern[ ]” the “agency’s path.” Alaska Dep’t of Envtl. Conservation v. EPA, 540 U.S. 461, 497, 124 S.Ct. 983, 157 L.Ed.2d 967 (2004) (citation omitted).
On the other hand, it is the Court’s job to ensure that the agency has “examine[d] the relevant data and [has] articulate[d] a satisfactory explanation for its action.” Motor Vehicle Mfrs. Ass’n of U.S., Inc. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 43, 103 S.Ct. 2856, 77 L.Ed.2d 443 (1983). The APÁ “established a scheme of ‘reasoned decisionmaking,’” and thus the “the process by which [an agency] reaches [its decreed.] result must be logical and rational.” Allentown Mack Sales & Serv., Inc. v. NLRB, 522 U.S. 359, 374, 118 S.Ct. 818, 139 L.Ed.2d 797 (1998) (quoting State Farm, 463 U.S. at 52, 103 S.Ct. 2856); see also, e.g., Tripoli Rocketry Ass’n v. Bureau of Alcohol, Tobacco, Firearms, & Explosives, 437 F.3d 75, 77 (D.C. Cir. 2006) (same); Fisher v. Pension Benefit Guarantee Corp., 151 F.Supp.3d 159, 165 (D.D.C. 2016) (same). As the Supreme Court explained in State Farm, “[t]he scope of review under the ‘arbitrary and capricious’ standard is narrow,” but the agency must still “articulate ... a ‘rational connection between the facts found and the choice made.’” 463 U.S. at 43, 103 S.Ct. 2856 (quoting Burlington Truck Lines, Inc. v. United States, 371 U.S. 156, 168, 83 S.Ct. 239, 9 L.Ed.2d 207 (1962)); see also Sw. Power Pool, Inc. v. FERC, 736 F.3d 994, 997 (D.C. Cir. 2013) (same). Although review of the agency’s reasoned decision is deferential, where the agency “entirely fail[s] to consider an important aspect of the problem” at issue, the Court must set the agency’s action aside as “arbitrary and capricious.” State Farm, 463 U.S. at 43, 103 S.Ct. 2856.
Applying these standards here, much of what the Service did is unobjectionable. In at least three key respects, however, the Listing Decision either failed to offer a rational connection between the facts and its conclusions or entirely failed to consider an important aspect of the problem. The Court, accordingly, will vacate the Listing Decision and remand to the Service for further consideration consistent with this opinion.
A. Challenges to the “Significant Portion of Its Range” Analysis
The most salient of these errors occurred in the Service’s determination that the species is not threatened in a “significant portion of its range.” As explained above, the Endangered Species Act requires that the Service list a species it if it is threatened “throughout all or a significant portion of its range.” 16 U.S.C. § 1532(20) (emphasis added). The Service understood the relevant “portions of [the] range” to be the five geographic stock complexes it had previously identified. See Listing Decision, 78 Fed. Reg. at 48,950, 48,993. According to its 2011 Draft SPR Policy, the Service was then required to ask “whether there is substantial information suggesting that the hypothetical loss of any of the[se] individual stock complexes ... would reasonably be expected to increase the demographic risks to the point that the [entire] species would then be in danger of extinction.” Id. at 48,993. Because the only stock complex for which the Service had statistically significant evidence of population decline was the Mid-Atlantic. stock complex, the Service performed the analysis only for that region. See id. If the loss of the Mid-Atlantic region would not place the entire species in danger of extinction, the Service reasoned, it “need not address the question whether the portion of the species occupying” that region was threatened or endangered. Id.
Against this backdrop, the Service dispensed with the SPR inquiry in just a few sentences. Given the centrality of this analysis to the Court’s holding, it is worth quoting in full:
For blueback herring, 3 of the stock complexes and the coastwide trend are all stable, but the [M]id-Atlantic stock complex is decreasing. The [internal status review team] determined that the [M]id-Atlantic stock complex is not significant to the species, given that[,] even though it is decreasing, the overall coastwide trend is stable. Thus, the loss of this stock complex would not place the entire species at risk of extinction. We concur with this conclusion. Because the portion of the blueback herring stock complex residing in the [Mid-Atlantic is not so significant that its hypothetical loss would render the species endangered, we conclude that the [M]id-Atlantic stock complex does not constitute a significant portion of the blueback herring’s range.
Id.; accord id. at 48,992 (explaining same rationale). This analysis, however, is based on a premise (that the coastwide trend was “stable”) and an assumption (that the Mid-Atlantic and coastwide complexes did not overlap) that are not supported by the Listing Decision. The Court will consider each of these propositions in turn.
1. Inference That the Coastwide Trend Was ‘‘Stable”
The Service’s determination that the Mid-Atlantic region does not constitute a significant portion of the blueback herring’s range depended on the factual premise that “the overall coastwide trend is stable.” Id. at 48,993. The Service’s only stated basis for that claim was the “coast-wide” trend analysis model, which estimated the average annual change in relative abundance of ocean-phase blueback herring, and generated a 95% confidence interval for that result. See supra Part I.C.2.b. As explained above, that estimate and its confidence interval are reflected in the top line of the following chart:
Figure 4 (repeated): Estimates and 95% Confidence Intervals for Each Population’s Average Annual Change in Relative Abundance
In making its decision, however, the Service did not consider the value of the point estimate (i.e., the midpoints identified above). Nor did it consider the length of the error bars. Instead, it considered only the fact that the 95% confidence interval “contained] zero.” Listing Decision, 78 Fed. Reg. at 48,987. In other words, because the data did not show with 95% confidence that the population size had changed, the Service “considered [the population] to be stable.” Id.-, accord id. at 48,989. Plaintiffs contend that this inference lacked the “rational connection between the facts found and the choice made” that the APA requires. State Farm, 463 U.S. at 43, 103 S.Ct. 2856; see Dkt. 27-3 at 21-29; Dkt. 34 at 11-17. In short, they argue that the absence of statistically significant evidence that the coastwide population is declining (or increasing) does not—absent more—show that it is stable. As explained below, the Court agrees with this undisputed tenet and, accordingly, concludes that the Service has committed one of two errors: It has either committed the logical error that Plaintiffs have identified or, at the very least, it has failed to explain why it has not done so. See State Farm, 463 U.S. at 43, 103 S.Ct. 2856.
It is helpful to begin with some background, none of which is disputed for present purposes. In conducting a formal significance test, researchers start from the hypothesis they are seeking to disprove, called the “null hypothesis” or “null.” David H. Kaye & David A. Freedman, Reference Guide on Statistics, in Reference Manual on Scientific Evidence 211, 241 (Fed. Judicial Ctr. 3d ed. 2011) [hereinafter Reference Guide]. They then ask: Assuming the null hypothesis is true, what is the probability of observing data that conflict with the null hypothesis to at least as great an extent as do the data actually observed? Id. at 249-61. To take a simple example, suppose a study seeks to draw inferences about the color of apples in an orchard, and begins from a random sample of 10 apples, 3 of which are green. If the null hypothesis is “most apples in this orchard are green,” the question would be: “If most apples in this orchard are, in fact, green, then what is the probability of choosing 10 apples at random from the orchard and finding 3 or fewer green ones?” If the answer falls below a predetermined significance threshold (often 6%), then the null hypothesis is sufficiently inconsistent with the data that it is deemed “rejected,” and the result is deemed “statistically significant.” Id. at 251-52, 120 S.Ct. 693; accord, e.g., Matrixx Initiatives, Inc. v. Siracusano, 563 U.S. 27, 39 n.6, 131 S.Ct. 1309, 179 L.Ed.2d 398 (2011) (explaining statistical significance). A “95% confidence interval,” then, is the interval containing all and only the null hypotheses that could not be rejected using a 5% significance threshold. Richard D. De Veaux et al., Stats: Data and Models 510-11 (2d ed. 2008); see also Reference Guide at 247.
Plaintiffs’ argument turns on the established principle that, when a statistical test fails to reject the null hypothesis, that does not by itself constitute evidence that the null hypothesis is true. See, e.g., Reference Guide at 251-52, 253-54; De Veaux et al. at 485, 501, 508. This concept is familiar in law: A criminal verdict of “not guilty,” for example, does not establish that the defendant did not commit the alleged conduct; it simply means that the government failed to disprove the assumption of innocence beyond a reasonable doubt. Helvering v. Mitchell, 303 U.S. 391, 397, 58 S.Ct. 630, 82 L.Ed. 917 (1938). So too in significance testing. Failing to reject the null does not mean that the null hypothesis accurately describes the world; “it simply means that we don’t have enough evidence to reject our assumption [that it does].” De Veaux et al. at 485 (drawing criminal law analogy). As the D.C. Circuit has explained, a “fail[urej to reject the null hypothesis” might mean that no trend in fact exists, but it is equally consistent with proposition that a trend does exist and the test “merely lacked sufficient power to detect [it].” Am. Petroleum Inst., 684 F.3d at 1350 (“[T]he study did not establish there was ‘no dose-response relationship’; it simply failed to reject the null hypothesis to that effect.”); see also, e.g., Smith v. Wyeth-Ayerst Labs. Co., 278 F.Supp.2d 684, 693 n.14 (W.D.N.C. 2003) (“A study may fail to disprove the null hypothesis, but that alone does not justify a conclusion that the null hypothesis has been proved.”); cf. Matrixx Initiatives, Inc., 563 U.S. at 40, 131 S.Ct. 1309 (“A lack of statistically significant [evidence of an effect] does not mean that
... experts have no reliable basis for [concluding that no effect exists].”). As a result, just as a court cannot conclude that a criminal defendant did not commit the underlying criminal conduct merely because the. jury failed to find sufficient evidence of guilt, reasoned decisionmaking does not permit an agency to conclude, based on a failure to reject the null hypothesis and without .further analysis, that the null hypothesis is true.
The Listing Decision, however, seems to have committed this very error. The Service defined the null hypothesis as the proposition that the relative abundance of ocean-phase blueback herring was the same in 2012 as it was in 1976 (ie., that the average change in relative abundance between those years was zero). The model, then, failed to reject the null. That is, zero was among the values in the confidence interval for the estimated change in abundance over the last 36 years—or, to put it in in different terms, the data did not show with a 95% degree of confidence that the number of ocean-phase blueback herring had changed between 1976 and 2012, Listing Decision, 78 Fed. Reg. at 48,990; see supra Figure 4 And, based on the model’s failure to reject the hypothesis that the relative abundance of the ocean-phase blueback herring had not changed, the Service concluded (or at least seems to have concluded) that the ocean-phase population was “stable.” Listing Decision, 78 Fed. Reg. at 48,987; see also Dkt, 29-1 at 44-45 (Defs.’ Brief) (confirming this description of the Listing Decision).
Before concluding that the Listing Decision was therefore unreasonable, the Court must, of course, ensure that it is not substituting its judgment for that of the agency, see State Farm, 463 U.S. at 43, 103 S.Ct. 2856, and that this not the type of technical issue that can reasonably lead to competing expert perspectives, see, e.g., Marsh, 490 U.S. at 378, 109 S.Ct. 1851. One could imagine, for example, that the technical details of the model somehow accounted for and nullified this putative error, Or perhaps Plaintiffs’ account of hypothesis testing—although “correct” enough to appear in college textbooks and the Federal Judicial Center’s statistics manual—is at odds with other, more complex statistical principles on which the Service relied. After three rounds of briefing and a lengthy oral argument, however, the Service has not even argued that such an explanation exists.
To start, the Service does not appear to dispute the mathematical premise of Plaintiffs’ argument, ie., that accepting an un-rejected null hypothesis as true, absent further analysis, is error. See Dkt. 29-1 at 39-48; Dkt. 37 at 12-17. To the contrary, the Service’s citations confirm Plaintiffs’ description of the relevant principles. The' Service directs the Court, for example, to a “commonly cited scholarly article,” Dkt. 29-1 at 45-46 & n.28, which characterizes Plaintiffs’ position as “well known among applied scientists,” John M. Hoenig & Dennis M. Heisey, The Abuse of Power: The Pervasive Fallacy of Power Calculations for Data Analysis, AMERICAN STATISTICIAN, Feb. 2001, at 1, 1. That article’s opening paragraph states:
It is well known among applied scientists that a lack of impact or effect is not sufficiently established by a failure to demonstrate statistical significance. A failure to reject the. null hypothesis of no effect may be the result of low statistical power when an important effect actually exists and the null hypothesis of no effect is in fact false.
Id. The Service also cites the website of Dr. Martha Smith, a retired statistics professor. See Dkt. 29-1 at 46 n.30. Her website explains that “[accepting a null hypothesis when a. result is not statistically significant, without taking power into account” is a “common [statistical] mistake[ ].” Martha K. Smith, Common Mistakes Involving Power (Aug. 28, 2012), http://www.ma.utexas.edu/users/mks/statmistakes/PowerMistakes.html. She continues:
Since smaller samples yield smaller power, a small sample size may not be able to detect an important difference. If there is strong evidence that the power of a procedure will indeed detect a difference of practical importance, then accepting the null hypothesis may be appropriate; otherwise it is not—all we can legitimately say then is that we fail to reject the null hypothesis.
Id. (footnote omitted) (emphasis added). Far from justifying the Listing Decision’s reasoning, these sources support the view that it was flawed.
Nor does the Service argue that it relied on the type of additional analysis that might have permitted it reasonably to draw affirmative conclusions from the failure to reject the null. One such type of analysis would evaluate the model’s “power,” which “is the chance that a statistical test will declare an effect when there is an effect to be declared.” Reference Guide at 254; accord De Veaux et al. at 515. The amount of power depends on both the size of the effect to be detected and the amount of data considered. Reference Guide at 254. When a low-powered test fails to reject the null hypothesis, the results are “more fairly described as inconclusive than negative.” Id. But, when a high-powered test fails to reject the null hypothesis, that “can be persuasive evidence” that the null is close to being correct. Id. Thus, demonstrating that the Service’s significance test had high power would be one way to bridge the gap between failing to reject the null and accepting it as true.
The Service, however, concedes that it did not conduct a power analysis. Indeed, it argues that it would have been inappropriate to do so, because power analyses “are most useful when designing a study (before data is collected),” and the data the Service used were collected before the status review began. See Dkt. 29-1 at 45, 47 (citing Hoenig & Heisey at 5; Smith). The statistical utility of a “post hoc power analysis” is beyond the judicial ken, but it is also beside the point. Plaintiffs do not argue, nor do their views entail, that a power analysis was required. Instead, they contend only that the Service impermissi-bly accepted an unrejected null as true. See Dkt. 34 at 16-17. The fact that the Service considered a power analysis infeasible does not cure that problem. A leaky ship is still leaky, even if it is not feasible to patch the leak after the ship has gone to sea. The Service, moreover, has not identified anything in the administrative record suggesting that it contemporaneously considered and rejected this—or any other— means of assessing whether the null hypothesis is true. See Dkt. 29-1 at 45, 47. All agree that the Court “must judge the propriety of [agency] action solely by the grounds invoked by the agency.” SEC v. Chenery Corp., 332 U.S. 194, 196, 67 S.Ct. 1760, 91 L.Ed. 1995 (1947); see Dkt. 48 at 5. Because the Service points to nothing in the administrative record suggesting that it even considered whether or how it might be able to confirm the truth of the null hypothesis, the Court cannot credit the Service’s “post hoc rationalization ]” now. Gerber v. Norton, 294 F.3d 173, 184 (D.C. Cir. 2002).
One could imagine the argument that the Service did not use the word “stable” to mean “stable,” but rather used it to mean that it lacked data demonstrating a statistically significant trend in population size. This line of reasoning, however, faces hurdles of its own. To the extent the Service indeed takes that position now, it has contradicted itself in its briefs. Nor did the Listing Decision itself state that it was employing such a counterintuitive definition. And, even if the Service did mean to use “stable” in this way, it has not explained how a finding of “stability”—understood to mean a lack of statistically significant evidence—would support the conclusions it reached.
As an initial matter, the Service does not advance in its briefs the argument that “stable” meant “unknown.” It writes, for example that “[t]he term ‘stable’ [in the Listing Decision] mean[t] that the stock[’s population] [wa]s neither increasing nor decreasing, because the estimated growth rate for the particular population [wa]s not statistically different from zero.” Dkt. 29-1 at 44. There is a substantial difference between asserting that the data -did not show whether the population was changing, and affirmatively concluding, as the Service appears to have done, that the population was, in fact, “neither increasing nor decreasing.” One assertion posits a lack of knowledge, while the other asserts a fact based on the absence of statistically significant evidence to the contrary.
The Service’s briefs go on to agree, moreover, that its inability to reject the null was consistent with at least two possibilities: (1) that the null hypothesis (that there was no trend) was actually true or (2) that there was a trend (ie., the null was false) but that the data lacked sufficient power to detect it. See Dkt. 37 at 13; Dkt. 53 at 69. The inability to distinguish those two possibilities, however, is precisely the problem. As the Service’s own sources explain, without some reason to favor the first possibility over the second, simply assuming the first to be true constitutes an unreasoned choice. Cf., e.g., Allentown, 522 U.S. at 374, 118 S.Ct. 818 (requiring “the process by which [an agency] reaches [its] result [to] be logical and rational). And, to the extent the Service intended to rely on the absence of evidence—that is, to rely on its inability to discern whether the coastwide population was increasing, decreasing, or stable—as a reason why it could not render a listing decision on the existing record, that effort fails because the Service never “articulate[d] [a] rational connection between” that lack of evidence and its listing decision. See State Farm, 463 U.S. at 43, 103 S.Ct. 2856.
When viewed in the context of the Listing Decision itself, this difficulty is acute. The Service recognized that the population of blueback herring is, in fact, .declining in the Mid-Atlantic region. The 2011 Draft SPR Policy required the Service then to ask, if the Mid-Atlantic stock complex went extinct, would the remainder of the species would become endangered? 76 Fed. Reg. at 77,002. But the Service asserted that it would not, because “the overall coastwide trend is stable.” Listing Decision, 78 Fed. Reg. at 48,993. That is, the Service concluded that the abundance of blueback herring in the “coastwide” region (ie., the ocean) was sufficient to protect the species against the hypothetical loss of the Mid-Atlantic stock complex. Although the Court does not foreclose the possibility that the Service might conclude that its lack of knowledge about whether the coastwide population would be sufficient to protect against such a loss required further study before the Service could find that listing the species was warranted, that is not what the agency said. To the contrary, the Service concluded that the coast-wide population “is stable,” that “the loss of [the Mid-Atlantic] stock, complex would not, place the entire species at risk of extinction,” and that “the [M]id-Atlantic stock complex does not constitute a significant portion of the blueback herring’s range.” Id. (emphases added). If the Service meant something else, it was required to say so and to offer a reasoned explanation for that alternative.
Ultimately, the Service’s main argument seems to be that the Court should defer to the Service’s statistical analysis because it involved complicated questions of statistics and ecology. See Dkt. 29-1 at 39-40; Dkt. 37 at 12-13; Dkt. 53 at 71-72. T