Endangered and Threatened Wildlife and Plants; Endangered Species Status for the Long Valley Speckled Dace

#  Endangered and threatened wildlife.

**AGENCY:**

Fish and Wildlife Service, Interior.

**ACTION:**

Proposed rule.

**SUMMARY:**

We, the U.S. Fish and Wildlife Service (Service), propose to list the Long Valley speckled dace ( *Rhinichthys nevadensis caldera* ), a fish native to California, as an endangered species under the Endangered Species Act of 1973, as amended (Act). This determination also serves as our 12-month finding on a petition to list the Long Valley speckled dace. After a review of the best available scientific and commercial information, we find that listing the subspecies is warranted. Accordingly, we propose to list the Long Valley speckled dace as an endangered species under the Act. If we finalize this rule as proposed, it would add this subspecies to the List of Endangered and Threatened Wildlife and extend the Act's protections to the subspecies. We have determined that designation of critical habitat for the Long Valley speckled dace is not determinable at this time.

**DATES:**

We will accept comments received or postmarked on or before October 7, 2024. Comments submitted electronically using the Federal eRulemaking Portal (see *ADDRESSES* , below) must be received by 11:59 p.m. eastern time on the closing date. We must receive requests for a public hearing, in writing, at the address shown in *FOR FURTHER INFORMATION CONTACT* by September 23, 2024.

**ADDRESSES:**

You may submit comments by one of the following methods:

(1) *Electronically:* Go to the Federal eRulemaking Portal: *https://www.regulations.gov.* In the Search box, enter FWS-R8-ES-2021-0065, which is the docket number for this rulemaking. Then, click on the Search button. On the resulting page, in the panel on the left side of the screen, under the Document Type heading, check the Proposed Rule box to locate this document. You may submit a comment by clicking on “Comment.”

(2) *By hard copy:* Submit by U.S. mail to: Public Comments Processing, Attn: FWS-R8-ES-2021-0065, U.S. Fish and Wildlife Service, MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.

We request that you send comments only by the methods described above. We will post all comments on *https://www.regulations.gov.* This generally means that we will post any personal information you provide us (see Information Requested, below, for more information).

*Availability of supporting materials:* Supporting materials, such as the species status assessment report, are available at *https://www.regulations.gov* at Docket No. FWS-R8-ES-2021-0065.

**FOR FURTHER INFORMATION CONTACT:**

Justin Barrett, Deputy Field Supervisor, Reno Fish and Wildlife Office, U.S. Fish and Wildlife Service, 1340 Financial Boulevard, Suite 234, Reno, NV 89502; telephone 775-861-6338. Individuals in the United States who are deaf, deafblind, hard of hearing, or have a speech disability may dial 711 (TTY, TDD, or TeleBraille) to access telecommunications relay services. Individuals outside the United States should use the relay services offered within their country to make international calls to the point-of-contact in the United States. Please see Docket No. FWS-R8-ES-2021-0065 on *https://www.regulations.gov* for a document that summarizes this proposed rule.

**SUPPLEMENTARY INFORMATION:**

**Executive Summary**

*Why we need to publish a proposed rule.* The Act (16 U.S.C. 1531 *et seq.* ) defines the term “species” as including any subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature. Under the Act, a species warrants listing if it meets the definition of an endangered species (in danger of extinction throughout all or a significant portion of its range) or a threatened species (likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range). If we determine that a species warrants listing, we must list the species promptly and designate the species' critical habitat to the maximum extent prudent and determinable. We have determined that the Long Valley speckled dace meets the definition of an endangered species; therefore, we are proposing to list it as such. Listing a species as an endangered or threatened species can be completed only by issuing a proposed rule through the Administrative Procedure Act rulemaking process (5 U.S.C. 551 *et seq.* ).

*What this document does.* We propose to list the Long Valley speckled dace as an endangered species under the Act.

*The basis for our action.* Under the Act, we may determine that a species is an endangered or threatened species because of any of five factors: (A) The present or threatened destruction, modification, or curtailment of its 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 its continued existence. We have determined that the Long Valley speckled dace is endangered due to the following threats: disease; introduced species; grazing; recreation; a trout hatchery; geothermal development; climate change; and effects of small population size.

Section 4(a)(3) of the Act requires the Secretary of the Interior (Secretary), to the maximum extent prudent and determinable, concurrently with listing designate critical habitat for the species. Section 3(5)(A) of the Act defines critical habitat as (i) the specific areas within the geographical area occupied by the species, at the time it is listed, on which are found those physical or biological features (I) essential to the conservation of the species and (II) which may require special management considerations or protection; and (ii) specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination by the Secretary that such areas are essential for the conservation of the species. Section 4(b)(2) of the Act states that the Secretary must make the designation on the basis of the best scientific data available and after taking into consideration the economic impact, the impact on national security, and any other relevant impacts of specifying any particular area as critical habitat.

We determined that designating critical habitat for the Long Valley speckled dace is prudent but not determinable at this time. We will coordinate with partners to obtain data sufficient to perform the required analysis of the impacts to inform our proposed critical habitat designation. When critical habitat is not determinable, the Act allows the Service an additional year to publish a critical habitat designation (16 U.S.C. 1533(b)(6)(C)(ii)).

**Information Requested**

We intend that any final action resulting from this proposed rule will be based on the best scientific and commercial data available and be as accurate and as effective as possible. Therefore, we request comments or information from other governmental agencies, Native American Tribes, the scientific community, industry, or any other interested parties concerning this proposed rule. We particularly seek comments concerning:

(1) The Long Valley speckled dace's biology, range, and population trends, including:

(a) Biological or ecological requirements of the subspecies, including habitat requirements for feeding, breeding, and sheltering;

(b) Genetics and taxonomy;

(c) Historical and current range, including distribution patterns and the locations of any additional populations of this subspecies;

(d) Historical and current population levels, and current and projected trends; and

(e) Past and ongoing conservation measures for the subspecies, its habitat, or both.

(2) Threats and conservation actions affecting the subspecies, including:

(a) Factors that may be affecting the continued existence of the subspecies, which may include habitat modification or destruction, overutilization, disease, predation, the inadequacy of existing regulatory mechanisms, or other natural or manmade factors;

(b) Biological, commercial trade, or other relevant data concerning any threats (or lack thereof) to this subspecies; and

(c) Existing regulations or conservation actions that may be addressing threats to this subspecies.

(3) Additional information concerning the historical and current status of this subspecies.

Please include sufficient information with your submission (such as scientific journal articles or other publications) to allow us to verify any scientific or commercial information you include.

Please note that submissions merely stating support for, or opposition to, the action under consideration without providing supporting information, although noted, do not provide substantial information necessary to support a determination. Section 4(b)(1)(A) of the Act directs that determinations as to whether any species is an endangered or a threatened species must be made solely on the basis of the best scientific and commercial data available.

You may submit your comments and materials concerning this proposed rule by one of the methods listed in *ADDRESSES* . We request that you send comments only by the methods described in *ADDRESSES* .

If you submit information via *https://www.regulations.gov,* your entire submission—including any personal identifying information—will be posted on the website. If your submission is made via a hardcopy that includes personal identifying information, you may request at the top of your document that we withhold this information from public review. However, we cannot guarantee that we will be able to do so. We will post all hardcopy submissions on *https://www.regulations.gov.*

Comments and materials we receive, as well as supporting documentation we  used in preparing this proposed rule, will be available for public inspection on *https://www.regulations.gov.*

Our final determination may differ from this proposal because we will consider all comments we receive during the comment period as well as any information that may become available after this proposal. Based on the new information we receive (and, if relevant, any comments on that new information), we may conclude that the Long Valley speckled dace is threatened instead of endangered, or we may conclude that the subspecies does not warrant listing as either an endangered species or a threatened species. In our final rule, we will clearly explain our rationale and the basis for our final decision, including why we made changes, if any, that differ from this proposal.

**Public Hearing**

Section 4(b)(5) of the Act provides for a public hearing on this proposal, if requested. Requests must be received by the date specified in *DATES* . Such requests must be sent to the address shown in *FOR FURTHER INFORMATION CONTACT* . We will schedule a public hearing on this proposal, if requested, and announce the date, time, and place of the hearing, as well as how to obtain reasonable accommodations, in the *Federal Register* and local newspapers at least 15 days before the hearing. We may hold the public hearing in person or virtually via webinar. We will announce any public hearing on our website, in addition to the *Federal Register* . The use of virtual public hearings is consistent with our regulations at 50 CFR 424.16(c)(3).

**Previous Federal Actions**

On June 24, 2020, the Service received a petition, dated June 8, 2020, from the Center for Biological Diversity (CBD) requesting that the Long Valley speckled dace and two other speckled dace entities in the Death Valley region be listed as endangered or threatened species and critical habitat be designated under the Act. On September 29, 2021, we published in the *Federal Register* (86 FR 53937) a 90-day finding that the petition presented substantial scientific or commercial information indicating that listing the Long Valley speckled dace may be warranted.

**Peer Review**

A species status assessment (SSA) team prepared an SSA report for the Long Valley speckled dace (Service 2023, entire). The SSA team was composed of Service biologists, in consultation with other species experts. The SSA report represents a compilation of the best scientific and commercial data available concerning the status of the species, including the impacts of past, present, and future factors (both negative and beneficial) affecting the species.

In accordance with our joint policy on peer review published in the *Federal Register* on July 1, 1994 (59 FR 34270), and our August 22, 2016, memorandum updating and clarifying the role of peer review in listing and recovery actions under the Act, we solicited independent scientific review of the information contained in the Long Valley speckled dace SSA report. We sent the SSA report to four independent peer reviewers and received responses from all four reviewers. Results of this structured peer review process can be found at *https://www.regulations.gov.* In preparing this proposed rule, we incorporated the results of these reviews, as appropriate, into the SSA report, which is the foundation for this proposed rule.

**Summary of Peer Reviewer Comments**

As discussed above in Peer Review, we received comments from four peer reviewers on the draft SSA report. We reviewed all comments for substantive issues and new information regarding the material contained in the SSA report. Reviewers generally provided additional references, clarifications, and suggestions for the SSA report. We updated the SSA report based on the information we received and worked with researchers to update the current and future condition analyses. Peer reviewer comments are addressed in the following summary, and information provided was incorporated into the SSA report as appropriate (Service 2023, entire).

*Comment 1:* A reviewer commented on cattails and other vegetation being a present threat at Whitmore Marsh and that removal of plants from selected areas may be beneficial for improving Long Valley speckled dace habitat.

*Our Response:* We added text to chapter 4.5.2.2 of the SSA report to describe the potential impacts of *Typha* spp. on the Long Valley speckled dace and its habitat.

*Comment 2:* A reviewer asked whether Lahontan cutthroat trout ( *Oncorhynchus clarkii henshawi* ) in the translocation site, O'Harrel Canyon Creek, would prey upon Long Valley speckled dace when migrating downstream in the winter.

*Our Response:* Lahontan cutthroat trout do have the potential to prey upon Long Valley speckled dace. We added text to chapter 3.1.5 of the SSA report discussing the potential for Lahontan cutthroat trout to move downstream as potential predators.

*Comment 3:* A reviewer asked if the estimate of the refuge population was adults only or if juveniles were included. They expressed concern that the estimate may be overestimated if juveniles were included.

*Our Response:* We added the range of sizes of collected individuals to clarify the information presented in chapter 4.6 of the SSA report, where we describe the refuge population in greater detail.

*Comment 4:* A reviewer questioned what “relatively stable” meant in terms of survey results conducted by the California Department of Fish and Wildlife (CDFW) at Whitmore Marsh. The reviewer commented that a stable population with low abundance is still at risk of extirpation. They also questioned whether the negative effects of removing fish from Whitmore Marsh, a small population, were considered.

*Our Response:* We added text to chapter 4.3.7 of the SSA report to clarify that the CDFW characterized the population as relatively stable during their 2002 and 2009 surveys, although CDFW did not define the term “relatively stable” and no abundance data or estimates were generated in those surveys. All available information is provided in chapter 4.3.7 of the SSA report.

*Comment 5:* A reviewer requested clarification on how high snowpack prevents movement of Long Valley speckled dace.

*Our Response:* We added text to chapter 4.3.7 of the SSA report to clarify that cold temperatures from meltwater could have contributed to Long Valley speckled dace concentrating in the upper reaches of Whitmore Marsh near the spring source and the pool discharge.

*Comment 6:* Two reviewers questioned the genetic health of the Whitmore Marsh northeast pond refugium and questioned whether genetics were considered in the translocation of Long Valley speckled dace to O'Harrel Canyon Creek.

*Our Response:* Fin clips of Long Valley speckled dace at White Mountain Research Center (WMRC) were collected for genetic analyses in 2021, but we are not aware of any results or information on the genetic health of the population from this study. The O'Harrel Canyon Creek population was sourced from White Mountain Research Center and the White Mountain Research Center population was sourced from Whitmore Marsh; therefore, the genetics for all three populations are the same.

*Comment 7:* A reviewer commented that the text describing populations not being significantly influenced by grazing is not true. They mentioned historical grazing impacts have substantially altered stream habitat, water levels, and riparian areas. The commenter clarified that while current grazing may not be impacting populations, contemporary grazing likely limits the abilities of these streams to recover. They also commented that restoring stream habitat may help offset climate impacts in the near term.

*Our Response:* We made changes to the text in chapter 4.5.3 of the SSA report to clarify that while grazing appears to impact habitat, it may have less immediate impact to individuals and the local population when considered relative to other threats.

*Comment 8:* A reviewer commented that the Hot Creek Trout Hatchery is not hydrologically connected to Whitmore Marsh and mentioned it is unclear why the hatchery is being considered a threat to this population.

*Our Response:* We made changes to the text in the Executive Summary and in the body of the SSA report in sections discussing Hot Creek (Table 4) and Hot Creek Springs (section 4.3.1 and Table 4) historical locations: (1) to discuss how the trout hatchery has potentially played a role in the extirpation of historical populations of the Long Valley speckled dace at the Hot Creek and Hot Creek Springs historical locations; and (2) to remove associated text from the discussion of current threats to the subspecies at Whitmore Marsh.

*Comment 9:* A reviewer commented that while Long Valley speckled dace are currently found in geothermal waters, there is no evidence that this is a habitat requirement. The reviewer mentioned that Whitmore Marsh is extremely cold in the winter, emphasizing that Long Valley speckled dace habitat associations are linked more closely to the absence of nonnative trout.

*Our Response:* We made changes to the text in chapter 3.2.2 of the SSA report to remove the word “thermal” from “thermal spring systems,” although we do acknowledge there may be some geothermal influence on Whitmore Marsh, as its waters do not freeze even during extremely cold winters.

*Comment 10:* A reviewer commented that absence of nonnative trout seems to be the single most important factor for the survival of Long Valley speckled dace. They clarified that Long Valley speckled dace are broadly tolerant of a range of water quality parameters, and this tolerance allows them to persist in marginal habitat where nonnative trout species cannot.

*Our Response:* We made changes to the text in chapter 3.2.2.1 of the SSA report to emphasize that the presence of nonnative species has a greater impact on the quality of habitat for Long Valley speckled dace than water quality does.

*Comment 11:* A reviewer questioned how the Hot Creek Trout Hatchery impacted Long Valley speckled dace populations given that other native minnows (tui chub ( *Siphateles bicolor* )) persist in the spring brooks to this day. The reviewer noted that the spring brook habitat described by Sada (1989, p. 13) is still intact and not impacted by the hatchery.

*Our Response:* We made changes to the text in chapter 4.5.5 of the SSA report to emphasize that there is not concrete evidence that the hatchery led to the extirpation of Long Valley speckled dace populations but also to acknowledge that the hatchery may have had an impact on the subspecies' habitat.

*Comment 12:* A reviewer commented that the status of the O'Harrel Canyon Creek population is unknown, and it should not be described as “established.”

*Our Response:* We removed the word “established” from the text in chapter 4.2 of the SSA report as a descriptor for the O'Harrel Canyon Creek population of Long Valley speckled dace.

*Comment 13:* A reviewer commented that there is no evidence to support the claim that the Hot Creek Trout Hatchery played a role in the extirpation of Long Valley speckled dace at previously occupied historical sites. They mentioned that the Owens tui chub ( *Siphateles bicolor snyderi* ) persisted in both spring brooks from which Long Valley speckled dace disappeared between 1933 and 1989. Long Valley speckled dace were also extirpated from that portion of Hot Creek away from the hatchery's influence.

*Our Response:* We made changes to the text in chapter 4.5.5 of the SSA report, adding a citation from Sada (1989, p. 3) that corroborates the potential impacts the Hot Creek Trout Hatchery may have had on the Long Valley speckled dace's habitat. In that discussion, we also removed the phrase “likely led to extirpation” and made other revisions to take the uncertainty into account.

*Comment 14:* One reviewer commented that the danger from fire caused by climate change is underrated in our analysis.

*Our Response:* We added a paragraph to chapter 4.5.7 of the SSA report addressing local fire risk and how precipitation may increase the risk of excessive sedimentation within local watersheds.

**I. Proposed Listing Determination**

**Background**

A thorough review of the taxonomy, life history, and ecology of the Long Valley speckled dace is presented in the SSA report (Service 2023, pp. 6-8).

The Long Valley speckled dace is a small freshwater fish with one remaining historical population within the 700,000 year old Long Valley volcanic caldera and one refugium population in Mono County, California. The subspecies previously occupied habitat in the Owens Basin in California ranging from cold-water streams to hot springs with water temperatures typically below 29 degrees Celsius (°C) (84.2 degrees Fahrenheit (°F)) (Moyle et al. 2015, p. 3). This subspecies was found in 7 historical sites, including 6 spring sites and one small stream. While the stream population suggests the subspecies is capable of surviving in stream habitats, its disappearance from the historical stream location following development of a hydrologically-connected spring suggested the stream population relied on recruitment from spring-dwelling individuals (Sada 1989, p. 13). Population collapses in six historical sites that were modified and invaded by nonnative fish species indicates that the Long Valley speckled dace is highly susceptible to changes in its habitat. The remaining occupied habitat includes two populations: one native population at Whitmore Marsh and one translocated population at the three sites in O'Harrel Canyon Creek. The CDFW also maintains a refugium population in an artificial pond at the WMRC.

The Long Valley speckled dace is a small minnow that typically measures less than 8 centimeters (cm) but can reach 11 cm standard length. This subspecies is distinguished by its small downfacing mouth, a thick caudal peduncle, small scales, and a pointed snout. The snout typically has a small barbel on each end of the maxilla (jaw) and a small patch of skin connects the snout to the upper lip. Adults usually have eight rays in their dorsal fin, which originates behind the beginning of the pelvic fins, whereas the anal fin has six to eight rays. Distinctive dark spots on the sides and upper parts of the body, as well as a dark lateral band running to the snout, usually occur once the fish becomes larger than 3 cm. The body is  an olive to darkish yellow, with the stomach area paler in color. During the breeding season, both males and females have orange- or red-tipped fins, with males also exhibiting red snouts and lips. Males often develop tubercles on their head and pectoral fins (Moyle 2002, p. 160).

The Long Valley speckled dace is a minnow (family = *Leuciscidae* ) in the genus *Rhinichthys.* In 1896, Jordan and Evermann divided *Rhinichthys osculus* into a complex of 10 species (Su et al. 2021, entire). Hubbs et al. (1974, entire) collapsed all of them into one species. In 2023, Moyle et al. (2023, entire) summarized the recent genomic findings and presented a revision of taxonomy for California dace populations. The new taxonomy consists of three species (Santa Ana speckled dace ( *R. gabrielino* ); desert speckled dace ( *R. nevadensis* ); and western speckled dace ( *R. klamathensis* )) and six subspecies, including the Long Valley speckled dace ( *R. n. caldera* ).

There is little information regarding the biology and life history of Long Valley speckled dace; therefore, the following description is based primarily on information for general speckled dace ( *Rhinichthys osculus* ) and historical and current collections of Long Valley speckled dace. General speckled dace lifespan is coarsely correlated with maximum size, with dace under 80 millimeters fork length living for roughly 3 years. Typically, females grow faster than males. Under stressful environmental conditions, limited food, or high population densities, growth rates can decrease. General speckled dace reach sexual maturity by the end of their second summer. Females produce 190-800 eggs, depending on size and location, and release them underneath rocks or near gravel surfaces while males release sperm.

General speckled dace's subterminal mouth and tooth structure make it ideal for consumption of small aquatic invertebrates most common in riffles (hydropsychid caddisflies, baetid mayflies, and chironomid and simuliid midges). Invertebrates generally make up the bulk of their diet; however, they may also eat filamentous algae (Moyle et al. 2015, p. 2). Speckled dace forage opportunistically, which varies their diet of invertebrates depending on available food sources that may change during the seasons. Speckled dace can be active both in the day and at night, with water temperatures influencing their level of activity. Speckled dace are active year-round when stream temperatures stay above 4 °C (39.2 °F).

Long Valley speckled dace likely originated during the late Pleistocene pluvial period when they colonized the upper Owens Valley region from Mono Lake Basin water that spilled into the Adobe Valley. The Adobe Valley drained into the Owens River and fish presumably swam upstream to Long Valley. The Owens River eventually down-vaulted and formed steep waterfalls in the gorge around 100,000 years ago, ultimately isolating Long Valley from Owens Valley. Long Valley speckled dace currently have limited ability to disperse between populations, as many of the springs they occupied historically are not hydrologically connected to other lakes or streams in the broader Death Valley region or are separated by unsuitable habitat.

**Regulatory and Analytical Framework**

**Regulatory Framework**

Section 4 of the Act (16 U.S.C. 1533) and the implementing regulations in title 50 of the Code of Federal Regulations set forth the procedures for determining whether a species is an endangered species or a threatened species, issuing protective regulations for threatened species, and designating critical habitat for endangered and threatened species. On April 5, 2024, jointly with the National Marine Fisheries Service, we issued a final rule that revised the regulations in 50 CFR part 424 regarding how we add, remove, and reclassify endangered and threatened species and what criteria we apply when designating listed species' critical habitat (89 FR 24300). On the same day, we published a final rule revising our protections for endangered species and threatened species at 50 CFR 17 (89 FR 23919). These final rules are now in effect and are incorporated into the current regulations.

The Act defines an “endangered species” as a species that is in danger of extinction throughout all or a significant portion of its range, and a “threatened species” as a species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. The Act requires that we determine whether any species is an endangered species or a threatened species because of any of the following factors:

(A) The present or threatened destruction, modification, or curtailment of its 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 its continued existence.

These factors represent broad categories of natural or human-caused actions or conditions that could have an effect on a species' continued existence. In evaluating these actions and conditions, we look for those that may have a negative effect on individuals of the species, as well as other actions or conditions that may ameliorate any negative effects or may have positive effects.

We use the term “threat” to refer in general to actions or conditions that are known to or are reasonably likely to negatively affect individuals of a species. The term “threat” includes actions or conditions that have a direct impact on individuals (direct impacts), as well as those that affect individuals through alteration of their habitat or required resources (stressors). The term “threat” may encompass—either together or separately—the source of the action or condition or the action or condition itself.

However, the mere identification of any threat(s) does not necessarily mean that the species meets the statutory definition of an “endangered species” or a “threatened species.” In determining whether a species meets either definition, we must evaluate all identified threats by considering the species' expected response and the effects of the threats—in light of those actions and conditions that will ameliorate the threats—on an individual, population, and species level. We evaluate each threat and its expected effects on the species, then analyze the cumulative effect of all of the threats on the species as a whole. We also consider the cumulative effect of the threats in light of those actions and conditions that will have positive effects on the species, such as any existing regulatory mechanisms or conservation efforts. The Secretary determines whether the species meets the definition of an “endangered species” or a “threatened species” only after conducting this cumulative analysis and describing the expected effect on the species.

The Act does not define the term “foreseeable future,” which appears in the statutory definition of “threatened species.” Our implementing regulations at 50 CFR 424.11(d) set forth a framework for evaluating the foreseeable future on a case-by-case basis, which is further described in the 2009 Memorandum Opinion on the foreseeable future from the Department of the Interior, Office of the Solicitor (M-37021, January 16, 2009; “M-Opinion,” available online at * https://  www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37021.pdf * ).

The foreseeable future extends as far into the future as the U.S. Fish and Wildlife Service and National Marine Fisheries Service (hereafter, the Services) can make reasonably reliable predictions about the threats to the species and the species' responses to those threats. We need not identify the foreseeable future in terms of a specific period of time. We will describe the foreseeable future on a case-by-case basis, using the best available data and taking into account considerations such as the species' life-history characteristics, threat projection timeframes, and environmental variability. In other words, the foreseeable future is the period of time over which we can make reasonably reliable predictions. “Reliable” does not mean “certain”; it means sufficient to provide a reasonable degree of confidence in the prediction, in light of the conservation purposes of the Act.

**Analytical Framework**

The SSA report documents the results of our comprehensive biological review of the best scientific and commercial data regarding the status of the species, including an assessment of the potential threats to the species. The SSA report does not represent our decision on whether the species should be proposed for listing as an endangered or threatened species under the Act. However, it does provide the scientific basis that informs our regulatory decisions, which involve the further application of standards within the Act and its implementing regulations and policies.

To assess the Long Valley speckled dace's viability, we used the three conservation biology principles of resiliency, redundancy, and representation (Shaffer and Stein 2000, pp. 306-310). Briefly, resiliency is the ability of the species to withstand environmental and demographic stochasticity (for example, wet or dry, warm or cold years); redundancy is the ability of the species to withstand catastrophic events (for example, droughts, large pollution events); and representation is the ability of the species to adapt to both near-term and long-term changes in its physical and biological environment (for example, climate conditions, pathogens). In general, species viability will increase with increases in resiliency, redundancy, and representation (Smith et al. 2018, p. 306). Using these principles, we identified the Long Valley speckled dace's ecological requirements for survival and reproduction at the individual, population, and subspecies levels, and described the beneficial and risk factors influencing the subspecies' viability.

The SSA process can be categorized into three sequential stages. During the first stage, we evaluated the individual subspecies' life-history needs. The next stage involved an assessment of the historical and current condition of the subspecies' demographics and habitat characteristics, including an explanation of how the subspecies arrived at its current condition. The final stage of the SSA involved making predictions about the subspecies' responses to positive and negative environmental and anthropogenic influences. Throughout all of these stages, we used the best available information to characterize viability as the ability of the subspecies to sustain populations in the wild over time, which we then used to inform our regulatory decision.

The following is a summary of the key results and conclusions from the SSA report; the full SSA report can be found at Docket No. FWS-R8-ES-2021-0065 on *https://www.regulations.gov.*

**Summary of Biological Status and Threats**

In this discussion, we review the biological condition of the subspecies and its resources, and the threats that influence the subspecies' current and future condition, in order to assess the subspecies' overall viability and the risks to that viability.

**Subspecies Needs**

For Long Valley speckled dace to have high viability, the subspecies needs to maintain its representation (adaptive capacity) by having multiple, sufficiently resilient populations (redundancy). Long Valley speckled dace is a narrow endemic and inherently has low redundancy; however, it is still important that multiple, adequately resilient populations exist throughout its range. This allows the subspecies to retain some redundancy and representation, which help mitigate impacts from threats and stochastic events. Having multiple populations helps maintain genetic diversity and adaptive capacity, which is increasingly important due to the impacts of climate change.

To have high viability, the Long Valley speckled dace would need consistent clean cold water (water temperatures that stay below 29 °C (84.2 °F) in the summer months) with access to aquatic invertebrates as a food source. Fertilized eggs and larvae utilize gravel substrates during development, and later larvae use rocks and emergent vegetation for cover. Adults typically inhabit springs but have also existed in creek systems. Populations need abundant individuals within habitat patches of adequate quality to maintain survival and reproduction despite disturbance. For Long Valley speckled dace, this revolves around having adequate aquifer-fed thermal spring systems or creeks that stay above 4 °C (39.2 °F). Having enough water in each spring or creek is important to allow dace within the population to disperse throughout the connected habitat during different seasons for reproductive purposes. Having multiple populations connected within the watershed is important to mitigate impacts from localized threats. Population size varies greatly based on the annual conditions of the habitat and will rebound in numbers when conditions are favorable.

The amount of habitat is mainly driven by snowmelt from the Sierra Nevada highlands on the western edge of the caldera (U.S. Geological Survey, undated). The subspecies inhabits a relatively small area, making adequate amounts of suitable habitat important for the resiliency of the subspecies. Quality of habitat revolves around water quality. For the subspecies, the water quality priorities are having water temperatures stay below 29 °C (84.2 °F) and limiting the amount of pollution and sedimentation in the waterways. Invasive species can also negatively impact habitat suitability directly by changing dissolved oxygen and pH levels of the water or by increasing predation and competition levels.

Capacity for population growth, particularly from low numbers, is important for the Long Valley speckled dace's resiliency. The Long Valley speckled dace currently occurs in low numbers, making it especially vulnerable to stochastic events. Having populations large enough to be self-sustaining and to be able to repopulate habitat in a highly variable and unpredictable environment is important for the Long Valley speckled dace's resiliency. In response to introduced species, disease, grazing, recreation, a trout hatchery, geothermal development, climate change, and small population size effects in the occupied habitat, Long Valley speckled dace populations must be resilient enough to repopulate habitat as environmental conditions change.

Although surveys have been completed at Whitmore Marsh as recently as 2023, the six extirpated historical sites have not been revisited as recently and assessed for current  habitat conditions because of previous surveys deeming them inhabitable. An overall population estimate, and subsequent population trends, are unknown for the subspecies outside of the Whitmore Marsh population. O'Harrel Canyon Creek was surveyed in 2023 and 2024 (Buckmaster 2023, pers. comm.; Buckmaster 2024, pers. Comm.), with documented evidence of survival and reproduction. However, it is currently unknown how effectively translocated Long Valley speckled dace can establish in a wild environment. Robust monitoring would be needed to estimate population levels as the total number of Long Valley speckled dace fluctuates year-to-year based on habitat conditions.

**Factors Influencing Subspecies Viability**

The following discussion provides a summary of the primary factors that affect or may affect the current and future condition of the Long Valley speckled dace. For our analysis, we evaluated impacts from the following primary threats to the subspecies: (1) disease; (2) nonnative species; (3) grazing; (4) recreation; (5) water diversion; (6) geothermal development; (7) climate change; and (8) effects of small population size.

**Disease**

Growth and health status of fish may be negatively affected by parasites (Raissy and Ansari 2012, p. 74). In general, parasites may cause stress, reduced growth, increased risk of infection or secondary disease, and possibly death of individual fish (Hejna et al. 2023, entire). For example, in 1988, Long Valley speckled dace found in Whitmore Marsh were in poor condition due to a heavy parasite infestation of yellow grub ( *Clinostomum marginatum* ) (Bogan et al. 2002, p. 4). Because of the documented negative impacts to Long Valley speckled dace, and because there is only one historical population of Long Valley speckled dace remaining, we consider disease to pose a threat to the viability of the Long Valley speckled dace.

**Nonnative Species**

The introduction of nonnative species may stress indigenous fish populations via increased predation, competitive interactions, transmission of pathogens, or hybridization (Cucherousset and Olden 2011, pp. 216-221; Mills et al. 2004, pp. 719-720). Western mosquitofish are the most common nonnative fish species that have led to the extirpation of isolated general speckled dace populations. Nonnative Lahontan tui chub ( *Gila bicolor* ) are also found in the range of the Long Valley speckled dace. Nonnative species can compete with or prey upon Long Valley speckled dace and may introduce parasites and disease into the freshwater ecosystems they inhabit (Stone et al. 2007, p. 131). Long Valley speckled dace have rarely been found in springs where other nonnative fish species are present, suggesting their ability to compete with or avoid predation from nonnatives is limited (Sada 1989, p. 10). For example, one Long Valley speckled dace population collapsed within a year of western mosquitofish and Lahontan tui chub ( *Gila bicolor* ) being recorded at the site, and the population is currently considered extirpated (Greene 2006, pers. comm., p. 4). Therefore, we consider nonnative species to pose a significant threat to the viability of Long Valley speckled dace populations.

**Grazing**

Cattle access is known to increase bank erosion, increasing turbidity and sedimentation in the springs. Long Valley speckled dace require clear water for their spawning and clean vegetation for egg laying. Sedimentation from cattle also has the potential to fill in spring pools and runs, reducing habitat area (American Fisheries Society, undated, entire). The increased turbidity and reduced riparian vegetation lead to increased water temperatures, which reduce dissolved oxygen levels and can stress Long Valley speckled dace and increase the competitive advantage for mosquitofish. Influxes of large amounts of cattle waste increase the amount of nutrients in the water and further reduce visibility, which can impact the spawning of Long Valley speckled dace. Higher levels of nutrients result in higher biological oxygen demand and reduce the dissolved oxygen levels in the water. Increased bacterial levels may also reduce egg viability and increase the risk of infection. Grazing has been occurring in Long Valley since before the discovery of Long Valley speckled dace, and historical grazing has altered stream habitat and riparian areas, such that it is less suitable habitat for the species. While historical grazing levels may have had detrimental impacts to Long Valley speckled dace habitat, the best available information indicates that while Whitmore Marsh and Little Alkali were historically heavily impacted by cattle grazing, both populations appeared to be stable at the time grazing impacts were observed (Sada, 1989, p. 12). Grazing still occurs at low levels around Whitmore Marsh and any impacts to habitat do not appear to be adversely affecting the population there. Thus, we do not consider grazing to be a significant threat to Long Valley speckled dace populations.

**Recreation**

Recreation activities in general may impact water quality, substrate and vegetation, and free-flowing water. The spring source that supplies Whitmore Marsh also feeds a public swimming pool. Historically, the pool has discharged lightly chlorinated water into the marsh from May to September (Cox 2023, p. 1), however chlorinated water is no longer discharged into the marsh. While the effluent from the spring is undiminished by pool operations and has maintained sufficient flows to support this Long Valley speckled dace population, the potential for an accidental spill of chlorinated water into the spring still exists. There is also potential for structural damage to the pool to result in leaks because of the age of the pool or by events such as seismic activity. Because of the proximity of the swimming pool to Whitmore Marsh we consider recreation to be a significant threat to the viability of this population.

**Water Diversion**

Surface water diversions have the potential to affect fish survival directly or indirectly. Water diversions reduce the amount of water available to stream resources and return the remaining water far from the intake. Flow alterations directly impact fish by blocking migration routes ( *e.g.,* trapping fish in dewatered sections) and by disrupting breeding habits. Diversions indirectly affect fish by removing stream habitat, degrading water quality parameters, and introducing competing nonnative species (American Fisheries Society, undated, p. 2). For example, Long Valley speckled dace individuals disappeared from Hot Creek shortly following the development of the Hot Creek Trout Hatchery (a CDFW-owned facility) and associated water diversions in the 1960s.

**Geothermal Development**

Prior to geothermal development of a particular area, the flow path of water underneath the land surface is usually not known with sufficient detail to understand and prevent surface impacts that may be caused by such development (Sorey 2000, p. 705). Changes associated with surface expression of thermal waters from geothermal production are common and are expected. Typical changes seen in geothermal fields across the globe include, but are not limited to, changes in water temperature, flow, and quality (Bonte et al. 2011, pp. 4-8; Chen et al.  2020, pp. 2-6; Kaya et al. 2011, pp. 55-64; Sorey 2000, entire), which are all needs of Long Valley speckled dace.

Changes in surface-expressed water temperature and flow from geothermal production areas have been documented within the Long Valley Caldera at historical localities where Long Valley speckled dace previously occurred and near the remaining population of the subspecies (Sorey 2000, entire). Geothermal pumping between 1985-1998 at Casa Diablo Geothermal Plant, part of Ormat Technologies, Inc., Mammoth Geothermal Complex, resulted in flow ceasing at Colton Spring and declines in water level at Hot Bubbling Pool (Sorey 2000, p. 706), which are located roughly 6.4 kilometers (km) (4 miles (mi)) and 4.8 km (3 mi) from Whitmore Marsh, respectively. Based on historical operations of the Casa Diablo Geothermal Plant and surface water monitoring at Whitmore Marsh, the remaining historical population of Long Valley speckled dace is outside of the range where detectable changes in surface features have occurred. However, the Casa Diablo-IV power plant that was put into service in 2022 nearly doubles the capacity of the geothermal facility, and future impacts from the operation of the expanded plant may extend farther into the Long Valley speckled dace's range. The doubled capacity plant has only been in service since July 2022. Monitoring of spring flow, temperature, and stage is not taking place at Whitmore Marsh, so the data required for an analysis of the condition of, or possible effects from local geothermal development to, the springs and surface water there are currently not available. Additionally, if the operation does cause effects to the geothermally sourced springs at Whitmore Marsh, propagation and expression of those effects may take time. Therefore, the best available information used to consider the impacts of geothermal development does not indicate that it is currently a threat to the species; however, we recognize the potential for population-level impacts should the effects of groundwater and geothermal extraction be realized at Whitmore Marsh.

**Climate Change**

Changes in climate, such as increasing temperatures, shifts in precipitation patterns, drought, and increases in wildfire have already been observed in California where Long Valley speckled dace occur, and such changes are expected to continue. Current climate change forecasts for terrestrial areas in the Northern Hemisphere predict warmer air temperatures, more intense precipitation events (both drought and flooding), and increased summer continental drying by the year 2100 (Intergovernmental Panel on Climate Change (IPCC) 2014, entire). Little is known about how and when spring flows may be affected by changes in climate. Direct hydrological connections have not been established in most cases, and for many areas, these connections remain difficult to make. Increased variations in temperature and precipitation in the range of the Long Valley speckled dace may result in effects on the life history of the subspecies. Thermal springs that comprise a major part of Long Valley are fed by aquifers dependent on snowmelt for recharge. Long Valley speckled dace are currently found in a hot-spring-fed marsh and a creek, with temperatures that stay below 29 °C (84.2 °F). Long Valley speckled dace are capable of withstanding elevated water temperatures (Moyle et al. 2015, p. 11), but the lethal upper temperature limit is unknown. Fish are generally more stressed at the upper extremes of their temperature range, and although they may be able to survive, elevated temperature is an example of a stressor that may affect them through reduced disease resistance (Moyle et al. 2015, p. 11). Average annual temperatures have increased almost 1.1 °C (1.9 °F) over the last century (Garfin et al. 2014, p. 464), and an additional increase of 1.9 to 5.3 °C (3.5 to 9.5 °F) is predicted to occur by the year 2100 (Walsh et al. 2014, p. 23). In recent decades, reductions in precipitation and winter snowpack have been observed, and this pattern is expected to continue (Garfin et al. 2014, p. 465). The frequency and intensity of these reductions have increased on a global scale (IPCC 2014, p. 77), and climate change is projected to reduce surface and groundwater resources in most subtropical deserts (IPCC 2014, p. 14).

Climate change is also predicted to increase fire frequency and severity. Whitmore Marsh, O'Harrel Canyon Creek, and certain historical sites (Little Alkali and Hot Creek Springs) are located within a moderate fire hazard severity zone. Other historical sites (Unnamed Spring and Sulfur Spring) are located within a high fire hazard severity zone. In the southern California mountains, debris flows can occur in both burned and unburned terrain. Wildfires greatly increase the likelihood of debris flows within the burned area by removing vegetation and temporarily elevating soil hydrophobicity (Staley et al. 2017, entire). Excess overland flow from intense precipitation events caused by climate change may exacerbate the effects of debris flows in areas affected by wildfire. When debris flows occur, they can cause significant erosion to hillslopes and channels, resulting in large amounts of sediment being carried downstream. This excessive sediment can have profound negative impacts on local wildlife, including fish such as the Long Valley speckled dace. Wildfire also eliminates vegetation that shades the water and moderates water temperature and may further impact water transport, sediment transport, water quality, and flow regime. Burned uplands in the watersheds may affect Long Valley speckled dace habitat by producing silt-and-ash-laden runoff that can fill in pools and significantly increase turbidity of rivers. Large wildfires have caused local extirpations in isolated Long Valley speckled dace occurrences (Expert Working Group 2023, p. 23). Wildfire may impact the Long Valley speckled dace throughout its remaining range, although the location, frequency, and size of these events cannot be precisely predicted.

Increased frequency of snow drought induced by climate change may also affect the flow rates and temperatures of hydrologic features inhabited by the Long Valley speckled dace (Hatchett and McEvoy 2018, pp. 11-12). Particularly due to the historical impacts of wildfire on Long Valley speckled dace habitat, and the potential effects a single large fire could have on the remaining historical population at Whitmore Marsh, we consider climate change to pose a significant threat to the subspecies.

**Effects of Small Population Size**

Historically, Long Valley speckled dace mostly occurred in small, isolated populations throughout the subspecies' range. The subspecies currently consists of a single wild population at Whitmore Marsh. Small, isolated populations are vulnerable to a number of deleterious effects, including: (1) demographic fluctuation due to random variation in birth and death rates and sex ratio; (2) environmental fluctuation in resource or habitat availability, predation, competitive interactions, and catastrophes; (3) reduction in cooperative interactions and subsequent decline in fertility and survival ( *i.e.,* Allee effects); (4) inbreeding depression reducing reproductive fitness; and (5) loss of genetic diversity reducing the ability to evolve and cope with environmental change (Traill et al. 2010, p. 29).

For example, small populations of Long Valley speckled dace are more  vulnerable to extirpation during environmental fluctuation, such as flooding (which can physically wash dace away), fire (and its subsequent impacts on Long Valley speckled dace habitat and water quality), or sustained drought (which can result in the loss or reduction of surface flows and concomitant increases in water temperature). Habitat fragmentation has subjected the small populations to genetic isolation, reduced space for rearing and reproduction, and reduced adaptive capabilities, and has increased the subspecies' likelihood of extinction. Isolation means that any remnant populations following these types of events caused by environmental fluctuation or habitat fragmentation are unlikely to benefit from demographic or genetic rescue, further elevating risks of inbreeding depression, loss of genetic diversity, and reductions in evolutionary potential that can contribute to population extirpation. These small population effects interact with other factors to pose a threat across the Long Valley speckled dace's current range. Thus, because the Long Valley speckled dace currently occurs in small, isolated populations, the magnitude of the threat posed by environmental stochasticity and inbreeding depression is elevated.

**Conservation Efforts and Regulatory Mechanisms**

At this time, Long Valley speckled dace is not listed under the California Endangered Species Act (CESA). Due to concerns over the future viability of the last remaining historical population of Long Valley speckled dace, CDFW staff deemed it necessary to establish a refugium population in an artificial pond at the White Mountain Research Center (WMRC) outside of the native range (Cox, 2021, p. 1). This population was sourced from individuals at Whitmore Marsh and a previous refuge population known as Becky's Pond, also sourced from Whitmore Marsh, which has since been extirpated. Although the refuge population appears stable, CDFW recommends continued monitoring for disease that may have been present in source individuals from Whitmore Marsh and management of water quality and water levels to maintain this population. Monitoring the genetic health of the refuge population will also be important for understanding and managing its long-term viability. The refugium population at WMRC represents a critical component of Long Valley speckled dace conservation and has already been used in translocation efforts.

Similar efforts to mitigate threats have also been initiated for the last remaining historical population. The public swimming pool operated by the town of Mammoth Lakes historically discharged chlorinated water into Whitmore Marsh, possibly contributing to the population decline occurring around 2017 (Cox, 2023, p. 1). The town has since made changes to the way the pool is managed and operated in order to limit the risk of introducing chlorinated water into the marsh in the future. A storage tank was constructed in 2022 to store discharged pool water until it can be transported off site to a sewage treatment plant (Cox, 2023, p. 2). This effort reduces the risk of chronic release events. In addition, the town of Mammoth Lakes has been coordinating with the Service to develop a management plan to implement response actions in the event of an accidental spill.

CDFW monitored the habitat at O'Harrel Canyon Creek in 2015-2016 and determined that drought did not have an effect on the creek despite the creek's size and watershed. These factors influenced CDFW to create a plan to translocate Long Valley speckled dace and create another wild population to supplement the Whitmore Marsh population. CDFW collected 413 Long Valley speckled dace from the Whitmore Marsh Complex Northeast pond refugium population on June 30, 2022. Collected Long Valley speckled dace were transported and released at three locations within O'Harrel Canyon Creek. Monitoring of these locations in 2023 and 2024 (Buckmaster 2023, pers. comm.; Buckmaster 2024, pers. comm.) indicated survival and reproduction; however, multiple years of monitoring will be needed to determine if this population successfully establishes.

**Cumulative and Synergistic Effects**

We note that, by using the SSA framework to guide our analysis of the scientific information documented in the SSA report, we have analyzed the cumulative effects of identified threats and conservation actions on the subspecies. To assess the current and future condition of the subspecies, we evaluate the effects of all the relevant factors that may be influencing the subspecies, including threats and conservation efforts. Because the SSA framework considers not just the presence of the factors, but to what degree they collectively influence risk to the entire subspecies, our assessment integrates the cumulative effects of the factors and replaces a standalone cumulative-effects analysis.

**Current Condition**

As mentioned previously, the Long Valley speckled dace is a narrow endemic subspecies known from seven historical sites within the Long Valley Caldera in Mono County, California. All but one of the seven historical sites are now thought to be extirpated (Moyle et al. 2015, p. 3). Because of the small spatial scale, few extant sites, limited survey data, and localized nature of the threats, we assessed the current conditions qualitatively by discussing rangewide factors affecting viability and by summarizing the available demographic and habitat information for each population. We then supplement the demographic and habitat quality data with a threats analysis for the extant wild population. We provide qualitative descriptions of the factors influencing viability and summarize these influences using a risk matrix approach to highlight major threats and their expected impacts.

**Resiliency**

Of seven known historical populations of Long Valley speckled dace, Whitmore Marsh is the sole remaining population and covers roughly 4,000-8,000 square meters (1-2 acres), based on accounts by Moyle et al. (2015, p. 3) and Geographic Information System calculations using satellite imagery of wetland vegetation over multiple years. In 2022, a population was translocated to O'Harrel Canyon Creek from the refuge population at White Mountain Research Center (Cox 2022, p. 2); however, it is uncertain whether this population will maintain viability over time.

The Long Valley speckled dace population in Whitmore Marsh was discovered in 1988 (Sada 1989, p. 10). Sada (1989, p. 11) visited this site four times between July 31 and December 12, 1988, to collect population size and habitat quality data. The habitat was supported by spring discharge that flowed through a chlorinated swimming pool owned and maintained by the Town of Mammoth Lakes on Los Angeles Department of Water and Power property. CDFW surveyed Whitmore Marsh again in 2002 and 2009, and found the population to be relatively stable. In 2011, Long Valley speckled dace were translocated from this site to a private pond (“Becky's Pond”), which was originally constructed in 2006. No population estimates were recorded at the time of the 2011 translocation. Individuals from Becky's Pond were later moved to a refuge population established at White Mountain Research Center. The Becky's Pond population  was supplemented with individuals from Whitmore Marsh in 2011 and then subsequently confirmed to be extirpated (Cox 2022, p. 2).

Low numbers at Whitmore Marsh over the past 7 years, including as few as two individuals being observed in 2021, have been attributed to a die-off that likely occurred in the spring of 2017. While the cause of the population crash is unknown, there are several threats in the area that may have led to the decline. One hypothesis is that an unusually heavy snowpack during the previous winter may have prevented the majority of Long Valley speckled dace from dispersing to colder reaches of the marsh. Long Valley speckled dace concentrating near the warm pool outlet stream could have also been exposed to chlorine from the public swimming pool upstream that historically discharged lightly chlorinated water into the marsh during the summer operating season. As mentioned previously, the swimming pool no longer discharges chlorinated water into the marsh. Other possible explanations for the population die-off include parasites, or unprecedented winter kill (Cox 2023, pp. 1-2). Although we do not have direct population estimates, such large decreases in the number of fish caught, suggest that the population has experienced dramatic declines that may limit its ability to persist.

O'Harrel Canyon Creek is a spring-fed creek situated at 2,083 meters (6,834 feet) of elevation in Mono County, California, near Benton Crossing. This creek originates in the Glass Mountains and terminates before reaching the Owens River. Introduced Lahontan cutthroat trout occupy the upper 0.8 km (0.5 mi) of the creek but are not found in the lower reaches that provide suitable habitat and water temperature for Long Valley speckled dace.

Monitoring efforts will be used to determine success of population establishment at O'Harrel Canyon Creek; however, heavy snowpack from the 2022/2023 winter season prevented staff members from accessing the site until later in 2023. Young of year were observed during that survey and surviving adults, including gravid females were observed in 2024. The initial success is encouraging, however more data across multiple years will be needed to determine if this population successfully establishes. Thus, the information available for these populations indicates that the overall resiliency for the Long Valley speckled dace is currently low.

**Representation**

Representation, or adaptive capacity, is maximized in a species with healthy populations distributed across the breadth of its evolutionary lineages and ecological niches that is capable of moving to new, suitable environments or capable of altering its physical or behavioral traits (phenotypes) to match changing environmental conditions through either plasticity or genetic change (Nicotra et al. 2015, p. 1270; Beever et al. 2016, p. 132). Although the general speckled dace complex appears to have inherent adaptive capacity, the Long Valley speckled dace's limited range, lack of dispersal opportunities, and presumed small population size likely limit this capacity for the subspecies. The wild and translocated populations of Long Valley speckled dace are not connected hydrologically, limiting any potential for dispersal in response to localized threats, as well as any ability for recolonization following catastrophic events. In addition, the lack of genetic exchange is concerning given the population decline at Whitmore Marsh that occurred in 2017. Managing genetic diversity both within the wild population and the translocated population will be critical to conservation efforts for the Long Valley speckled dace and maintenance of the subspecies' adaptive capacity.

**Redundancy**

The Long Valley speckled dace has lost roughly 83-99 percent of its historical extent of occurrence. Such a dramatic reduction in range for a narrowly distributed subspecies suggests that the Long Valley speckled dace currently has little if any redundancy to withstand the impact of the threats present within the Long Valley Caldera, which have led to extirpations of six historical populations.

**Summary of Current Condition**

The available data suggest that the remaining historical population has recently experienced a decline and may be persisting at extremely low densities relative to previous surveys. The declines observed at Whitmore Marsh are concerning because multiple threats exist on the landscape that are not part of the historical environmental variation experienced by this population. These are also the threats that likely caused impacts leading to the extirpation of six of seven historical populations of Long Valley speckled dace. The threats still posing a high risk to the subspecies' overall viability include nonnative species, recreation, water diversion, climate change, and small population size effects. Reduced abundance at the Whitmore Marsh may limit the ability of the population to withstand the synergistic effects of multiple threats and is a concern for the viability of the subspecies.

Any decrease in the resiliency of the Whitmore Marsh population places a large burden on the refuge population at the White Mountain Research Center for maintaining the viability of the subspecies. Although the population at the White Mountain Research Center appears to be currently stable, other populations in private/artificial ponds have failed (Cox 2022, p. 2), and maintaining the refuge population in more than one pond would decrease the chances of a catastrophic event affecting this entire population. Additionally, we do not know if the recently translocated population at O'Harrel Canyon Creek has survived and successfully reproduced. While translocation will likely be a key conservation action for this subspecies, evidence of successful reproduction would be required to meaningfully increase resiliency or redundancy across the subspecies' range.

**Future Condition**

As part of the SSA, we also developed several future-condition scenarios to forecast the condition of the subspecies under different projections of threats. We used our existing assessment of current habitat as the starting point for our future scenarios. We then incorporated projections of factors likely to impact the viability of the Long Valley speckled dace into the future. Although there are several factors that may influence the condition of the subspecies in the future, we focused on (1) introduced species; (2) disease; (3) grazing; (4); water diversion; (5) recreation; (6) geothermal development; (7) climate change; and (8) effects of small population size as the threats most likely to impact the Long Valley speckled dace's habitat and long-term viability. Because we determined that the current condition of the Long Valley speckled dace is consistent with an endangered species (see Determination of Long Valley Speckled Dace's Status, below), we are not presenting the results of the future scenarios in this proposed rule. Please refer to the SSA report (Service 2023, pp. 38-43) for the full analysis of future scenarios.

**Determination of Long Valley Speckled Dace's Status**

The Act defines the term “species” as including any subspecies of fish or wildlife or plants, and any distinct  population segment of any species of vertebrate fish or wildlife which interbreeds when mature (16 U.S.C. 1532(16)). Section 4 of the Act (16 U.S.C. 1533) and its implementing regulations (50 CFR part 424) set forth the procedures for determining whether a species meets the definition of an endangered species or a threatened species. The Act defines an “endangered species” as a species in danger of extinction throughout all or a significant portion of its range, and a “threatened species” as a species likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range. The Act requires that we determine whether a species meets the definition of an endangered species or a threatened species because of any of the following factors: (A) The present or threatened destruction, modification, or curtailment of its 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 its continued existence.

**Status Throughout All of Its Range**

We have determined that the Long Valley speckled dace is likely extirpated in six of seven known historical populations, with recent declines in the only known extant population possibly caused by a number of factors, including: impacts associated with a recreational swimming pool (Factor E), parasites and disease (Factor C, or unprecedented winter kill (Factor E). We anticipate that nonnative species will pose an additional threat to the persistence of the existing population (Factor C). Further, it is unknown whether the recently translocated population at O'Harrel Canyon Creek will establish and reproduce and be able to contribute to overall viability. Representation for the subspecies is low due to limited range, lack of dispersal opportunities between the remaining historic population and translocated population, and small population size. Redundancy for the Long Valley speckled dace is extremely low following the loss of historical populations.

After evaluating threats to the subspecies and assessing the cumulative effect of the threats under the Act's section 4(a)(1) factors, the Long Valley speckled dace does not have sufficient resiliency, representation, and redundancy to sustain viability. Recent declines at the only known extant population at Whitmore Marsh likely limit the ability of the subspecies to persist. A catastrophic event, such as a severe storm or wildfire, affecting one or both of the populations could result in the extinction of the subspecies. Other threats that may impact the sole remaining historical population, and uncertainty over the viability of the translocated population, place the subspecies at risk of extinction. Thus, after assessing the best available information, we determine that the Long Valley speckled dace is in danger of extinction throughout all of its range.

**Status Throughout a Significant Portion of Its Range**

Under the Act and our implementing regulations, a species may warrant listing if it is in danger of extinction or likely to become so within the foreseeable future throughout all or a significant portion of its range. We have determined that the Long Valley speckled dace is in danger of extinction throughout all of its range and accordingly did not undertake an analysis of any significant portions of its range. Because the Long Valley speckled dace warrants listing as endangered throughout all of its range, our determination does not conflict with the decision in *Center for Biological Diversity* v. *Everson,* 435 F. Supp. 3d 69 (D.D.C. 2020), because that decision related to significant portion of the range analyses for species that warrant listing as threatened, not endangered, throughout all of their range.

**Determination of Status**

Our review of the best available scientific and commercial information indicates that the Long Valley speckled dace meets the Act's definition of an endangered species. Therefore, we are proposing to list the Long Valley speckled dace as an endangered species in accordance with sections 3(6) and 4(a)(1) of the Act.

**Available Conservation Measures**

Conservation measures provided to species listed as endangered or threatened species under the Act include recognition as a listed species, planning and implementation of recovery actions, requirements for Federal protection, and prohibitions against certain practices. Recognition through listing results in public awareness, and conservation by Federal, State, Tribal, and local agencies, foreign governments, private organizations, and individuals. The Act encourages cooperation with the States and other countries and calls for recovery actions to be carried out for listed species. The protection required by Federal agencies, including the Service, and the prohibitions against certain activities are discussed, in part, below.

The primary purpose of the Act is the conservation of endangered and threatened species and the ecosystems upon which they depend. The ultimate goal of such conservation efforts is the recovery of these listed species, so that they no longer need the protective measures of the Act. Section 4(f) of the Act calls for the Service to develop and implement recovery plans for the conservation of endangered and threatened species. The goal of this process is to restore listed species to a point where they are secure, self-sustaining, and functioning components of their ecosystems.

The recovery planning process begins with development of a recovery outline made available to the public soon after a final listing determination. The recovery outline guides the immediate implementation of urgent recovery actions while a recovery plan is being developed. Recovery teams (composed of species experts, Federal and State agencies, nongovernmental organizations, and stakeholders) may be established to develop and implement recovery plans. The recovery planning process involves the identification of actions that are necessary to halt and reverse the species' decline by addressing the threats to its survival and recovery. The recovery plan identifies recovery criteria for review of when a species may be ready for reclassification from endangered to threatened (“downlisting”) or removal from protected status (“delisting”), and methods for monitoring recovery progress. Recovery plans also establish a framework for agencies to coordinate their recovery efforts and provide estimates of the cost of implementing recovery tasks. Revisions of the plan may be done to address continuing or new threats to the species, as new substantive information becomes available. The recovery outline, draft recovery plan, final recovery plan, and any revisions will be available on our website as they are completed ( *https://www.fws.gov/program/endangered-species* ), or from our Reno Fish and Wildlife Office (see *FOR FURTHER INFORMATION CONTACT* ).

Implementation of recovery actions generally requires the participation of a broad range of partners, including other Federal agencies, States, Tribes, nongovernmental organizations, businesses, and private landowners. Examples of recovery actions include habitat restoration ( *e.g.,* restoration of native vegetation), research, captive propagation and reintroduction, and  outreach and education. The recovery of many listed species cannot be accomplished solely on Federal lands because their ranges may occur primarily or solely on non-Federal lands. To achieve recovery of these species requires cooperative conservation efforts on private, State, and Tribal lands.

If the Long Valley speckled dace is listed, funding for recovery actions will be available from a variety of sources, including Federal budgets, State programs, and cost-share grants for non-Federal landowners, the academic community, and nongovernmental organizations. In addition, pursuant to section 6 of the Act, the State of California would be eligible for Federal funds to implement management actions that promote the protection or recovery of the Long Valley speckled dace. Information on our grant programs that are available to aid species recovery can be found at: *https://www.fws.gov/service/financial-assistance.*

Although the Long Valley speckled dace is only proposed for listing under the Act at this time, please let us know if you are interested in participating in recovery efforts for this subspecies. Additionally, we invite you to submit any new information on this subspecies whenever it becomes available and any information you may have for recovery planning purposes (see *FOR FURTHER INFORMATION CONTACT* ).

Section 7 of the Act is titled Interagency Cooperation, and it mandates all Federal action agencies to use their existing authorities to further the conservation purposes of the Act and to ensure that their actions are not likely to jeopardize the continued existence of listed species or adversely modify critical habitat. Regulations implementing section 7 are codified at 50 CFR part 402.

Section 7(a)(2) states that each Federal action agency shall, in consultation with the Secretary, ensure that any action they authorize, fund, or carry out is not likely to jeopardize the continued existence of a listed species or result in the destruction or adverse modification of designated critical habitat. Each Federal agency shall review its action at the earliest possible time to determine whether it may affect listed species or critical habitat. If a determination is made that the action may affect listed species or critical habitat, formal consultation is required (50 CFR 402.14(a)), unless the Service concurs in writing that the action is not likely to adversely affect listed species or critical habitat. At the end of a formal consultation, the Service issues a biological opinion, containing its determination of whether the Federal action is likely to result in jeopardy or adverse modification.

In contrast, section 7(a)(4) of the Act requires Federal agencies to confer with the Service on any action which is likely to jeopardize the continued existence of any species proposed to be listed under the Act or result in the destruction or adverse modification of critical habitat proposed to be designated for such species. Although the conference procedures are required only when an action is likely to result in jeopardy or adverse modification, action agencies may voluntarily confer with the Service on actions that may affect species proposed for listing or critical habitat proposed to be designated. In the event that the subject species is listed or the relevant critical habitat is designated, a conference opinion may be adopted as a biological opinion and serve as compliance with section 7(a)(2) of the Act.

Examples of discretionary actions for the Long Valley speckled dace that may be subject to conference and consultation procedures under section 7 of the Act are land management or other landscape-altering activities on Federal lands administered by the U.S. Forest Service and Bureau of Land Management, as well as actions on State, Tribal, local, or private lands that require a Federal permit (such as a permit from the U.S. Army Corps of Engineers under section 404 of the Clean Water Act (33 U.S.C. 1251 *et seq.* ) or a permit from the Service under section 10 of the Act) or that involve some other Federal action (such as funding from the Federal Highway Administration, Federal Aviation Administration, or the Federal Emergency Management Agency). Federal actions not affecting listed species or critical habitat—and actions on State, Tribal, local, or private lands that are not federally funded, authorized, or carried out by a Federal agency—do not require section 7 consultation. Federal agencies should coordinate with the Reno Fish and Wildlife Office (see *FOR FURTHER INFORMATION CONTACT* ) with any specific questions on section 7 consultation and conference requirements.

The Act and its implementing regulations set forth a series of general prohibitions and exceptions that apply to endangered wildlife. The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR 17.21, make it illegal for any person subject to the jurisdiction of the United States to commit, to attempt to commit, to solicit another to commit, or to cause to be committed any of the following acts with regard to endangered wildlife: (1) import into, or export from, the United States; (2) take (which includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct) within the United States, within the territorial sea of the United States, or on the high seas; (3) possess, sell, deliver, carry, transport, or ship, by any means whatsoever, any such wildlife that has been taken illegally; (4) deliver, receive, carry, transport, or ship in interstate or foreign commerce, by any means whatsoever and in the course of commercial activity; or (5) sell or offer for sale in interstate or foreign commerce. Certain exceptions to these prohibitions apply to employees or agents of the Service, the National Marine Fisheries Service, other Federal land management agencies, and State conservation agencies.

We may issue permits to carry out otherwise prohibited activities involving endangered wildlife under certain circumstances. Regulations governing permits for endangered wildlife are codified at 50 CFR 17.22 and general Service permitting regulations are codified at 50 CFR part 13. With regard to endangered wildlife, a permit may be issued: for scientific purposes, for enhancing the propagation or survival of the species, or for take incidental to otherwise lawful activities. The statute also contains certain exemptions from the prohibitions, which are found in sections 9 and 10 of the Act.

**II. Critical Habitat**

**Background**

Critical habitat is defined in section 3 of the Act as:

(1) The specific areas within the geographical area occupied by the species, at the time it is listed in accordance with the Act, on which are found those physical or biological features

(a) Essential to the conservation of the species, and

(b) Which may require special management considerations or protection; and

(2) Specific areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species.

Our regulations at 50 CFR 424.02 define the geographical area occupied by the species as an area that may generally be delineated around species' occurrences, as determined by the Secretary ( *i.e.,* range). Such areas may include those areas used throughout all  or part of the species' life cycle, even if not used on a regular basis ( *e.g.,* migratory corridors, seasonal habitats, and habitats used periodically, but not solely by vagrant individuals).

Conservation, as defined under section 3 of the Act, means to use and the use of all methods and procedures that are necessary to bring an endangered or threatened species to the point at which the measures provided pursuant to the Act are no longer necessary. Such methods and procedures include, but are not limited to, all activities associated with scientific resources management such as research, census, law enforcement, habitat acquisition and maintenance, propagation, live trapping, and transplantation, and, in the extraordinary case where population pressures within a given ecosystem cannot be otherwise relieved, may include regulated taking.

Critical habitat receives protection under section 7 of the Act through the requirement that each Federal action agency ensure, in consultation with the Service, that any action they authorize, fund, or carry out is not likely to result in the destruction or adverse modification of designated critical habitat. The designation of critical habitat does not affect land ownership or establish a refuge, wilderness, reserve, preserve, or other conservation area. Such designation also does not allow the government or public to access private lands. Such designation does not require implementation of restoration, recovery, or enhancement measures by non-Federal landowners. Rather, designation requires that, where a landowner requests Federal agency funding or authorization for an action that may affect an area designated as critical habitat, the Federal agency consult with the Service under section 7(a)(2) of the Act. If the action may affect the listed species itself (such as for occupied critical habitat), the Federal agency would have already been required to consult with the Service even absent the designation because of the requirement to ensure that the action is not likely to jeopardize the continued existence of the species. Even if the Service were to conclude after consultation that the proposed activity is likely to result in destruction or adverse modification of the critical habitat, the Federal action agency and the landowner are not required to abandon the proposed activity, or to restore or recover the species; instead, they must implement “reasonable and prudent alternatives” to avoid destruction or adverse modification of critical habitat.

Under the first prong of the Act's definition of critical habitat, areas within the geographical area occupied by the species at the time it was listed are included in a critical habitat designation if they contain physical or biological features (1) which are essential to the conservation of the species and (2) which may require special management considerations or protection. For these areas, critical habitat designations identify, to the extent known using the best scientific data available, those physical or biological features that are essential to the conservation of the species (such as space, food, cover, and protected habitat).

Under the second prong of the Act's definition of critical habitat, we can designate critical habitat in areas outside the geographical area occupied by the species at the time it is listed, upon a determination that such areas are essential for the conservation of the species.

Section 4 of the Act requires that we designate critical habitat on the basis of the best scientific data available. Further, our Policy on Information Standards Under the Endangered Species Act (published in the *Federal Register* on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), and our associated Information Quality Guidelines provide criteria, establish procedures, and provide guidance to ensure that our decisions are based on the best scientific data available. They require our biologists, to the extent consistent with the Act and with the use of the best scientific data available, to use primary and original sources of information as the basis for recommendations to designate critical habitat.

When we are determining which areas should be designated as critical habitat, our primary source of information is generally the information from the SSA report and information developed during the listing process for the species. Additional information sources may include any generalized conservation strategy, criteria, or outline that may have been developed for the species; the recovery plan for the species; articles in peer-reviewed journals; conservation plans developed by States and counties; scientific status surveys and studies; biological assessments; other unpublished materials; or experts' opinions or personal knowledge.

Habitat is dynamic, and species may move from one area to another over time. We recognize that critical habitat designated at a particular point in time may not include all of the habitat areas that we may later determine are necessary for the recovery of the species. For these reasons, a critical habitat designation does not signal that habitat outside the designated area is unimportant or may not be needed for recovery of the species. Areas that are important to the conservation of the species, both inside and outside the critical habitat designation, will continue to be subject to: (1) Conservation actions implemented under section 7(a)(1) of the Act; (2) regulatory protections afforded by the requirement in section 7(a)(2) of the Act for Federal agencies to ensure their actions are not likely to jeopardize the continued existence of any endangered or threatened species; and (3) the prohibitions found in section 9 of the Act. Federally funded or permitted projects affecting listed species outside their designated critical habitat areas may still result in jeopardy findings in some cases. These protections and conservation tools will continue to contribute to recovery of the species. Similarly, critical habitat designations made on the basis of the best available information at the time of designation will not control the direction and substance of future recovery plans, habitat conservation plans, or other species conservation planning efforts if new information available at the time of those planning efforts calls for a different outcome.

**Critical Habitat Determinability**

Our regulations at 50 CFR 424.12(a)(2) state that critical habitat is not determinable when one or both of the following situations exist:

(i) Data sufficient to perform required analyses are lacking, or

(ii) The biological needs of the species are not sufficiently well known to identify any area that meets the definition of “critical habitat.”

When critical habitat is not determinable, the Act allows the Service an additional year to publish a critical habitat designation (16 U.S.C. 1533(b)(6)(C)(ii)).

We reviewed the available information pertaining to the biological needs of the Long Valley speckled dace and habitat characteristics where this subspecies is located. A careful assessment of the economic impacts that may occur due to a critical habitat designation is still ongoing, and we are in the process of acquiring the complex information needed to perform that assessment. Therefore, due to the current lack of data sufficient to perform  required analyses, we conclude that the designation of critical habitat for the Long Valley speckled dace is not determinable at this time.

**Required Determinations**

**Clarity of the Rule**

We are required by E.O.s 12866 and 12988 and by the Presidential Memorandum of June 1, 1998, to write all rules in plain language. This means that each rule we publish must:

(1) Be logically organized;

(2) Use the active voice to address readers directly;

(3) Use clear language rather than jargon;

(4) Be divided into short sections and sentences; and

(5) Use lists and tables wherever possible.

If you feel that we have not met these requirements, send us comments by one of the methods listed in *ADDRESSES* . To better help us revise the rule, your comments should be as specific as possible. For example, you should tell us the numbers of the sections or paragraphs that are unclearly written, which sections or sentences are too long, the sections where you feel lists or tables would be useful, etc.

**Government-to-Government Relationship With Tribes**

In accordance with the President's memorandum of April 29, 1994 (Government-to-Government Relations with Native American Tribal Governments; 59 FR 22951, May 4, 1994), E.O. 13175 (Consultation and Coordination with Indian Tribal Governments), the President's memorandum of November 30, 2022 (Uniform Standards for Tribal Consultation; 87 FR 74479, December 5, 2022), and the Department of the Interior's manual at 512 DM 2, we readily acknowledge our responsibility to communicate meaningfully with federally recognized Tribes and Alaska Native Corporations (ANCs) on a government-to-government basis. In accordance with Secretary's Order 3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal Trust Responsibilities, and the Endangered Species Act), we readily acknowledge our responsibilities to work directly with Tribes in developing programs for healthy ecosystems, to acknowledge that Tribal lands are not subject to the same controls as Federal public lands, to remain sensitive to Indian culture, and to make information available to Tribes. We will continue to coordinate with Tribal entities throughout the rulemaking process to list the Long Valley speckled dace as an endangered species.

**References Cited**

A complete list of references cited in this rulemaking is available on the internet at *https://www.regulations.gov* and upon request from the Reno Fish and Wildlife Office (see *FOR FURTHER INFORMATION CONTACT* ).

**Authors**

The primary authors of this proposed rule are the staff members of the Fish and Wildlife Service's Species Assessment Team and the Reno Fish and Wildlife Office.

**List of Subjects in 50 CFR Part 17**

Endangered and threatened species, Exports, Imports, Plants, Reporting and recordkeeping requirements, Transportation, Wildlife.

**Proposed Regulation Promulgation**

Accordingly, FWS proposes to amend part 17, subchapter B of chapter I, title 50 of the Code of Federal Regulations, as set forth below:

**PART 17—ENDANGERED AND THREATENED WILDLIFE AND PLANTS**

1. The authority citation for part 17 continues to read as follows:

**Authority:**

16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, unless otherwise noted.

2. In § 17.11, in paragraph (h), amend the List of Endangered and Threatened Wildlife by adding an entry for “Dace, Long Valley speckled” in alphabetical order under FISHES to read as follows:

§ 17.11

(h) * * *

| Common name | Scientific name | Where listed | Status | Listing citations and applicable rules |
| --- | --- | --- | --- | --- |
|  |  |  |  |  |
| *         *         *         *         *         *         * |  |  |  |  |
|  |  |  |  |  |
|  |  |  |  |  |
| *         *         *         *         *         *         * |  |  |  |  |
| Dace, Long Valley speckled |  | Wherever found | E | [
                                
                                 citation when published as a final rule]. |
|  |  |  |  |  |
| *         *         *         *         *         *         * |  |  |  |  |

Martha Williams,

Director, U.S. Fish and Wildlife Service.