50 CFR Document 2019-23737
Endangered and Threatened Wildlife and Plants; Threatened Species Status for West Coast Distinct Population Segment of Fisher With Section 4(d) Rule
July 17, 2020
CFR

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Revised proposed rule; availability of proposed section 4(d) rule; and reopening of comment period.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), notify the public that we are making changes to our October 7, 2014, proposed rule to list the West Coast Distinct Population Segment (DPS) of fisher (Pekania pennanti) as a threatened species under the Endangered Species Act (Act). Based on new information since 2014 and a reconsideration of the best available information in our files (including all comments received to date), we are revising the proposed rule to list the DPS as a threatened species under the Act. We also propose a concurrent rule under section 4(d) of the Act for this DPS. We are reopening the comment period to allow comments on the new information presented in this document relevant to the changes and proposed 4(d) rule described below. If we finalize this listing rule as proposed, it would extend the Act's protections to this DPS and, accordingly, add this DPS to the List of Endangered and Threatened Wildlife.

DATES:

We will accept comments received or postmarked on or before December 9, 2019. Please note that if you are using the Federal eRulemaking Portal (see ADDRESSES, below), the deadline for submitting an electronic comment is 11:59 p.m. Eastern time on this date. We must receive requests for public hearings, in writing, at the address shown in FOR FURTHER INFORMATION CONTACT by December 23, 2019.

ADDRESSES:

You may submit comments by one of the following methods:

(1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. In the Search box, enter FWS-R8-ES-2018-0105, which is the docket number for this rulemaking. Then, click on the Search button. On the resulting page, in the Search panel on the left side of the screen, under the Document Type heading, click on the Proposed Rule box to locate this document. You may submit a comment by clicking on “Comment Now!” Please ensure that you have found the correct rulemaking before submitting your comment.

(2) By hard copy: Submit by U.S. mail or hand delivery to: Public Comments Processing, Attn: Docket No. FWS-R8-ES-2018-0105; U.S. Fish and Wildlife Service, MS: JAO/1N, 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 http://www.regulations.gov. This generally means that we will post any personal information you provide us (see “Public Comments,” below). See Information Requested, below, for more information on submitting comments on the proposed rule.

Document availability: The revised proposed rule is available on http://www.regulations.gov at Docket No. FWS-R8-ES-2018-0105 and on our website at https://www.fws.gov/​Yreka. Comments and materials we received during previous comment periods for the preceding proposed rule, as well as supporting documentation we used in preparing the preceding proposed rule, are also available for public inspection at Docket No. FWS-R8-ES-2014-0041. In addition, the supporting files for this revised proposed rule will be available for public inspection, by appointment, during normal business hours, at our Yreka Fish and Wildlife Office, 1829 South Oregon Street, Yreka, CA 96097; telephone 530-842-5763.

FOR FURTHER INFORMATION CONTACT:

Jenny Ericson, Field Supervisor, Yreka Fish and Wildlife Office, telephone: 530-842-5763. Direct all questions or requests for additional information to: WEST COAST DPS FISHER QUESTIONS, U.S. Fish and Wildlife Service, Yreka Fish and Wildlife Office, 1829 South Oregon Street, Yreka, CA 96097. Persons who use a telecommunications device for the deaf may call the Federal Relay Service at 1-800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

Why we need to publish a rule. Under the Act, if we determine that a species may be an endangered or threatened species throughout all or a significant portion of its range, we are required to promptly publish a proposal in the Federal Register and make a determination on our proposal within 1 year. To the maximum extent prudent and determinable, we must designate critical habitat for any species that we determine to be an endangered or threatened species under the Act. Listing a species as an endangered or threatened species and designation of critical habitat can only be completed by issuing a rule.

What this document does. This document revises the proposed rule to add the West Coast DPS of fisher (Pekania pennanti) as a threatened species to the List of Endangered and Threatened Wildlife in title 50 of the Code of Federal Regulations at 50 CFR 17.11(h) and proposes a rule under section 4(d) of the Act (a “4(d) rule”).

The basis for our action. Under the Act, we may determine that a species is an endangered or threatened species based on 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 threats to the West Coast DPS of fisher are loss and fragmentation of habitat resulting from high-severity wildfire and wildfire suppression (i.e., loss of snags and other large habitat structures on which the species relies, which are removed for human safety concerns), climate change, forest insects and tree diseases, and vegetation management; and potential direct impacts to individuals (e.g., increased mortality, decreased reproductive rates, increased stress/hormone levels, alterations in behavioral patterns) from wildfire, increased temperatures resulting from climate change, disease and predation, exposure to toxicants, and potential effects associated with small population size. These factors are resulting in a cumulative effect to such a degree that the best available information indicates the West Coast DPS of fisher meets the definition of a threatened species.

Peer review. In accordance with our joint policy on peer review published in the Federal Register on July 1, 1994 (59 FR 34270), we sought the expert opinions of multiple appropriate specialists on the 2014 draft Species Report to ensure that our decisions are based on scientifically sound data, assumptions, and analyses. Information received has been incorporated into the final (2016) Species Report and this revised proposed rule. Because we will consider all comments and information received during the comment period, our final determination may differ from this proposal. Based on the new information we receive (and any comments on that new information), we may conclude that the species is endangered instead of threatened, or we may conclude that the species does not warrant listing as either an endangered species or a threatened species. Such final decisions would be a logical outgrowth of this proposal as long as we: (a) Base the decisions on the best scientific and commercial data available after considering all of the relevant factors; (2) do not rely on factors Congress has not intended us to consider; and (3) articulate a rational connection between the facts found and the conclusions made, including why we changed our conclusion.

Information Requested

We will accept written comments and information during this reopened comment period on our revised proposed listing for the West Coast DPS of fisher. We will consider information and recommendations from all interested parties. We intend that any final action resulting from this revised proposal be as accurate as possible and based on the best available scientific and commercial data.

We are particularly interested in new information and comments regarding:

(1) Information related to anticoagulant and neurotoxicant rodenticides, and other toxicants, including law enforcement information and trend data.

(2) Information regarding population trend studies or data for the West Coast DPS of fisher, including information regarding areas that have been surveyed compared to areas that have not been surveyed, as well as all positive and negative survey results to help us assess distribution and population trends.

(3) Information regarding the threat of wildfire, including studies or information pertaining to current and future trends in wildfire frequency and severity, as well as information pertaining to the immediate response of fishers to post-fire landscapes in the West Coast DPS of fisher.

(4) Information regarding changes in low- to mid-elevation forests in different eco-regions within the range of the West Coast DPS of fisher, including scope and severity of vegetation management on Federal and non-Federal lands.

(5) Information regarding any effects associated with population size and isolation relevant to the West Coast DPS of fisher (e.g., low reproductive capacity, inbreeding depression, demographic and environmental stochasticity).

(6) Information regarding any effects of ongoing and widespread tree mortality in the Sierra Nevada range on the West Coast DPS of fisher.

(7) Information regarding any conservation efforts designed to benefit the West Coast DPS of fisher that have been planned or implemented since the October 7, 2014, proposed rule.

(8) Information regarding our revised DPS determination.

(9) Information on regulations that are necessary and advisable for the conservation of the West Coast DPS of fisher to include in a section 4(d) rule for the species. Section 4(d) of the Act provides that when a species is listed as a threatened species, the Secretary shall issue such regulations as he deems necessary and advisable to provide for the conservation of such species. The Service has proposed such measures here and will evaluate ideas provided by the public in considering the prohibitions that are appropriate to include in the 4(d) rule.

(10) The reasons why we should or should not designate habitat as “critical habitat” under section 4 of the Act (16 U.S.C. 1531 et seq.) including information to inform the following factors such that a designation of critical habitat may be determined to be not prudent:

(a) The species is threatened by taking or other human activity and identification of critical habitat can be expected to increase the degree of such threat to the species;

(b) The present or threatened destruction, modification, or curtailment of a species' habitat or range is not a threat to the species, or threats to the species' habitat stem solely from causes that cannot be addressed through management actions resulting from consultations under section 7(a)(2) of the Act;

(c) Areas within the jurisdiction of the United States provide no more than negligible conservation value, if any, for a species occurring primarily outside the jurisdiction of the United States;

(d) No areas meet the definition of critical habitat;

(11) Specific information on:

(a) The amount and distribution of habitat for the West Coast DPS of fisher,

(b) What areas, that are considered occupied at the time of listing and that contain the physical or biological features essential to the conservation of the species, should be included in the designation and why,

(c) Special management considerations or protection that may be needed in critical habitat areas we may propose, including managing for the potential effects of climate change, and

(d) What areas not occupied at the time of listing are essential for the conservation of the species. We particularly seek comments regarding:

(i) Whether occupied areas are inadequate for the conservation of the species; and,

(ii) Specific information that may support a determination that unoccupied areas will, with reasonable certainty, contribute to the conservation of the species and, contain at least one physical or biological feature essential to the conservation of the species.

(12) Any probable economic, national security, or other relevant impacts of designating any area that may be included in a proposed and final designation, and the benefits of including or excluding areas that may be impacted.

As indicated under SUMMARY, above, if you previously submitted comments or information on the October 7, 2014, proposed rule, please do not resubmit them. We have incorporated previously submitted comments into the public record, and we will fully consider them in the preparation of our final determination. Our final determination concerning this revised proposed listing will take into consideration all written comments and any additional information we have received since April 18, 2016 (81 FR 22710).

You may submit your comments and materials concerning the revised 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 http://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 http://www.regulations.gov.

Public Hearing

Section 4(b)(5) of the Act provides for one or more public hearings on this proposal, if requested. Requests for public hearings must be received by the date specified in DATES at the address shown in FOR FURTHER INFORMATION CONTACT. We will schedule public hearings on this proposal, if any are requested, and announce the dates, times, and places of those hearings, as well as how to obtain reasonable accommodations, in the Federal Register and local newspapers at least 15 days before the hearing.

Previous Federal Actions

We first found the West Coast DPS of fisher (previously delineated as a contiguous area encompassing parts of the three States of Washington, Oregon, and California) to be warranted for listing in 2004 and each subsequent year in the annual Candidate Notice of Review. On October 7, 2014, we proposed to list the West Coast DPS of fisher as a threatened species under the Endangered Species Act of 1973, as amended (Act; 16 U.S.C. 1531 et seq.) (79 FR 60419; Docket No. FWS-R8-ES-2014-0041). On April 18, 2016, we withdrew the proposed rule to list the West Coast DPS of fisher (81 FR 22710), concluding that the potential threats (stressors) acting upon the DPS were not of sufficient imminence, intensity, or magnitude to indicate that they were singly or cumulatively resulting in significant impacts at either the population or rangewide scales.

On October 19, 2016, the Center for Biological Diversity, Environmental Protection Information Center, Klamath-Siskiyou Wildlands Center, and Sierra Forest Legacy filed a complaint for declaratory and injunctive relief, alleging that our determination on the West Coast DPS of fisher violated the Act. By Order Re: Summary Judgment issued on September 21, 2018, the District Court for the Northern District of California vacated the listing withdrawal and remanded the Service's final determination for reconsideration. The Court's amended order, dated November 20, 2018, directs the Service to prepare a new determination by September 21, 2019.

On January 31, 2019, we reopened the comment period on the October 7, 2014, proposed rule to list the DPS as a threatened species (84 FR 644).

On May 17, 2019, the District Court for the Northern District of California granted a request by the Service for a 35-day extension to comply with the November 20, 2018, order as a result of delays due to the Federal Government's lapse in appropriations that prohibited the Service from working on this determination. The Court's amended order directed the Service to submit for publication a final listing determination or notice of a revised proposed rule by October 26, 2019, and in the event of publishing a revised proposed rule, submit for publication a final listing determination by April 25, 2020.

Additional information on Federal actions concerning the West Coast DPS of fisher prior to October 7, 2014, is outlined in the October 7, 2014, proposed listing rule (79 FR 60419) (hereafter referred to as the 2014 Proposed Rule).

Summary of Changes From the 2014 Proposed Rule

In this revised proposed listing rule, we incorporate additional information regarding the fishers, their habitat, and threats potentially impacting the species or its habitat; make clarifications regarding the delineation of the DPS; include a proposed 4(d) rule; and provide some changes to the structure of the rule as they relate to our analysis and policy information. Specifically:

(1) We have revised our delineation of the DPS for the West Coast population of fishers. In the 2014 Proposed Rule, we explained that the West Coast DPS encompassed the area where fishers historically occurred throughout western Washington, western Oregon, and California to the Sierra Nevada. We further elaborated that the West Coast DPS occurred in two original native populations (Northern California-Southwestern Oregon Population [NCSO] and the Southern Sierra Nevada Population [SSN]), three reintroduced populations (Northern Sierra Nevada Reintroduced Population [NSN] in California, Southern Oregon Cascades Reintroduced Population [SOC] in Oregon, and the Olympic Peninsula Reintroduced Population [ONP] in Washington). In this revised proposed listing rule, the West Coast DPS is now identified as comprising the two extant historically native subpopulations, NCSO and SSN, as well as the NSN and SOC subpopulations that resulted from reintroductions within a portion of the historical range of the DPS. Our decision to revise the DPS was predominantly based on: (a) The apparent absence of any extant historically native subpopulations in Washington or northern Oregon; and (b) the marked separation of the fisher subpopulations in the NCSO, SOC, NSN, and SSN from fishers reintroduced in Washington.

(2) The structure of this revised proposed rule varies slightly from the 2014 Proposed Rule. Information is organized in roughly the same order, although new sections have been added or sections have been revised to accommodate new information received since 2014; we have also updated policy standards and added discussion where relevant (e.g., addition of a section on the DPS's resiliency, redundancy, and representation).

(3) New information has been added to this revised proposed rule that was not available for the 2014 Proposed Rule or 2014 draft Species Report (Service 2014, entire). Our record also includes our 2016 final Species Report (Service 2016, entire).

(4) At the time of the 2014 Proposed Rule, fisher populations in Oregon and California were identified and described as the historically native extant NCSO and SSN subpopulations, the NSN subpopulation established with fishers from the NCSO subpopulation, and the SOC subpopulation established with fishers from British Columbia and Minnesota populations. Since that time, the best available information indicates that the range of the NCSO subpopulation is adjacent to the range of the (reintroduced) SOC subpopulation, with documented interbreeding activity occurring in the SOC range (Pilgrim and Schwartz 2016, entire; Pilgrim and Schwartz 2017, entire). Therefore, we determined it was appropriate to conduct our new evaluation of the status of the DPS by including the contribution of the SOC, along with the other three subpopulations (NCSO, SSN, and NSN), to the DPS's overall viability.

(5) We added a proposed section 4(d) rule because we determined it was necessary and advisable to issue protective regulations in order to reduce the likelihood of the West Coast DPS of fisher becoming an endangered species. Under our proposed section 4(d) rule, with specific exceptions, all prohibitions and provisions that apply to endangered wildlife under section 9(a)(1) of the Act would apply to the DPS. The specific exceptions from prohibitions include forestry management activities for the purposes of reducing the risk or severity of wildfires, forestry management activities pursuant to an approved fisher conservation plan or strategy, forestry management activities that are consistent with the conservation needs of the fisher but are not specifically designed as fisher conservation plans or strategies, and management activities designed to identify and clean-up toxicant-contaminated sites.

Distinct Population Segment Analysis

Under section 3(16) of the Act, we may consider for listing any species, including subspecies, of fish, wildlife, or plants, or any DPS of vertebrate fish or wildlife that interbreeds when mature (16 U.S.C. 1532(16)). Such entities are considered eligible for listing under the Act (and, therefore, are referred to as listable entities), should we determine that they meet the definition of an endangered or threatened species.

Under the Service's DPS Policy, three elements are considered in the decision concerning the determination and classification of a possible DPS as threatened or endangered. These elements include:

(1) The discreteness of a population in relation to the remainder of the species to which it belongs;

(2) The significance of the population segment to the species to which it belongs; and

(3) The population segment's conservation status in relation to the Act's standards for listing, delisting, or reclassification (i.e., is the population segment endangered or threatened).

In considering a DPS analysis for fisher involving the segment of the species' distribution that historically occupied suitable habitat in portions of the three Pacific Coast States (western Washington, western Oregon, and northern California and the Sierra Nevada mountain range, i.e., the West Coast range), we examined information in published range maps, published works that included historical occurrences, unpublished studies related to fisher distribution, and other submitted data, including comments received previously and during the most recent comment period (January 31, 2019; 84 FR 644). The historical distribution of fishers in this West Coast range is discussed in detail in the “Prehistorical and Historical Distribution across the Range of the Species” section of the final Species Report (Service 2016, pp. 25-26). As described above in Summary of Changes from the 2014 Proposed Rule, the current distribution of fishers in the West Coast range comprises various subpopulations, including several that had been established by introducing fishers taken from other parts of the species' range into areas in the West Coast range that supported fishers historically. These “nonnative” fishers, from British Columbia and Alberta, Canada, as well as from Minnesota, have established breeding populations in various parts of Washington (British Columbia- and Alberta-origin fishers) and southern Oregon (SOC; British Columbia- and Minnesota-origin fishers). These subpopulations of nonnative fishers in the West Coast range are in addition to the extant historically native subpopulations (NCSO and SSN) in southern Oregon and California. Therefore, while the West Coast range of fishers was historically occupied by fishers native to this region, it is now occupied both by fishers native to the three Pacific Coast States, as well as by fishers whose lineage was derived from nonnative fishers.

Further examination of this distribution clarifies that the northern portion of the West Coast range, the State of Washington and the northern part of Oregon, appears unoccupied by any subpopulations of native fishers, but nonnative fishers reintroduced in the State of Washington continue to persist and reproduce in several areas (although it is too soon to conclude that these breeding individuals will persist). By contrast, the southern portion of the West Coast range (i.e., southern Oregon, northern California, and the southern Sierra Nevada) is predominantly occupied by subpopulations of native fishers. However, this southern portion of the range also includes the SOC subpopulation of reintroduced nonnative fishers, which has now been documented as interbreeding with native fishers of the NCSO (Pilgrim and Schwartz 2016, entire; Pilgrim and Schwartz 2017, entire).

Our 2014 Proposed Rule represented our response to the petition that was filed seeking the listing of the West Coast DPS of fisher, consisting of fishers in Washington, Oregon, and California. At that time, we recognized that the West Coast DPS encompassed the area where fishers historically occurred throughout western Washington, western Oregon, and California to the Sierra Nevada. We are now proposing a different DPS based on the apparent absence of any extant, historically native subpopulations in Washington or northern Oregon, and the marked separation of the fisher subpopulations within the newly identified DPS to the fishers that have been reintroduced from British Columbia and Alberta into the Olympic National Park and the southern and northern Washington Cascades in Washington State. Based on this demographic and geographic disparity between the northern and southern portions of the range, coupled with the fact that there is currently no tangible connection between nonnative fishers in the northern portion and the native and nonnative fishers occupying the southern portion, we now have determined that the appropriate DPS to consider in this evaluation was the segment consisting of the southern subpopulations, i.e., NCSO, SSN, NSN, and SOC. Below, we summarize discreteness and significance for this DPS.

Discreteness

Under the DPS policy, a population segment of a vertebrate taxon may be considered discrete if it satisfies either one of the following conditions:

(1) It is markedly separated from other populations of the same taxon as a consequence of physical, physiological, ecological, or behavioral factors. Quantitative measures of genetic or morphological discontinuity may provide evidence of this separation.

(2) It is delimited by international governmental boundaries within which differences in control of exploitation, management of habitat, conservation status, or regulatory mechanisms exist that are significant in light of section 4(a)(1)(D) of the Act.

The West Coast DPS of fisher is markedly separate from other North American fisher populations of the east by enormous distances, geographical barriers, unsuitable habitat, and urban development. Fishers in this DPS are separated from the Rocky Mountains and the rest of the taxon in the central and eastern United States by natural physical barriers including the nonforested high desert areas of the Great Basin in Nevada and eastern Oregon. Other physical barriers that separate the West Coast population from Rocky Mountain and eastern U.S. fisher populations include major highways, urban and rural open-canopied areas, agricultural development, and other nonforested areas. In addition, all West Coast DPS subpopulations are markedly separate from the nearest other fisher populations to the north by approximately 270 miles (mi) (430 kilometers (km)), well beyond the various reported dispersal distances (as described in more detail in Service 2016, pp. 13-14). An additional component contributing to marked separation between the DPS subpopulations and fishers in Washington is the Columbia River and adjacent human developments (e.g., roads and towns), which likely acts as a physical impediment to crossing by any fishers dispersing in either direction. Therefore, it is extremely unlikely that any transient individuals from the DPS subpopulations could disperse far enough to reach the Washington range of reintroduced fishers, and even if they attempted to do so, they would likely not be able to cross the Columbia River. In summary, the subpopulations comprising the West Coast DPS of fisher are all geographically isolated from all other subpopulations of the species. Therefore, the marked separation condition for discreteness is met by geographical barriers, urban development, and distances that are beyond the known dispersal distance of fishers.

Significance

If a population segment is considered discrete under one or more of the conditions described in the Service's DPS policy, its biological and ecological significance will be considered in light of Congressional guidance that the authority to list DPSs be used “sparingly” (see Senate Report 151, 96th Congress, 1st Session). In making this determination, we consider available scientific evidence of the DPS's importance to the taxon to which it belongs. Since precise circumstances are likely to vary considerably from case to case, the DPS policy does not describe all the classes of information that might be used in determining the biological and ecological importance of a discrete population. However, the DPS policy describes four possible classes of information that provide evidence of a population segment's biological and ecological importance to the taxon to which it belongs. As specified in the DPS policy (61 FR 4722, February 7, 1996), this consideration of the population segment's significance may include, but is not limited to, the following:

(1) Persistence of the DPS in an ecological setting unusual or unique to the taxon;

(2) Evidence that loss of the DPS would result in a significant gap in the range of a taxon;

(3) Evidence that the DPS represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historical range; or

(4) Evidence that the DPS differs markedly from other populations of the species in its genetic characteristics.

To be considered significant, a population segment needs to satisfy only one of these conditions, or other classes of information that might bear on the biological and ecological importance of a discrete population segment, as described in the DPS policy (61 FR 4722, February 7, 1996). For the fisher, we found that loss of the West Coast DPS would result in a significant gap in the range of the taxon. Losing the West Coast DPS would significantly impact representation of the species by shifting the southern boundary of the taxon approximately 900 mi (1,448 km) to the north. Therefore, the significance element of the DPS policy is met for the West Coast DPS of fisher.

Summary of DPS Analysis

Given that both the discreteness and significance elements of the DPS policy are met, we find that the West Coast DPS of fisher is a valid DPS, and therefore a listable entity under the Act. We now assess the DPS's conservation status in relation to the Act's standards for listing (i.e., whether this DPS meets the definition of an endangered or threatened species under the Act).

Background

At the time of the 2014 Proposed Rule, a comprehensive draft Species Report (Service 2014, entire) was prepared that included new genetic and survey information. This report was subsequently updated in 2016 with additional information related to taxonomy, habitat, life-history characteristics (e.g., reproduction), habitat description, habitat use (e.g., dispersal and food habits), distribution and abundance, and potential threats across Washington, Oregon, and California (Service 2016, entire). Information related to the resources on which the species relies, conditions the species may experience currently or in the future, and threats (i.e., an activity or process that may have some negative effect on fishers or their habitat) are outlined in these reports and summarized herein where applicable. These reports, coupled with new information available since 2016 and our reconsideration of the best available scientific and commercial data, including comments received in connection with the 2014 Proposed Rule and our January 31, 2019 (84 FR 644), Federal Register document, provide the scientific basis that informs our regulatory decision regarding the range of the DPS, and whether the DPS should be listed as an endangered or threatened species under the Act. New information available since 2016 and the results of our reconsideration of the best available scientific and commercial information are presented in this revised proposed rule.

I. Revised Proposed Listing Determination

Species Information and Distribution

The fisher is a medium-sized, light brown to dark blackish-brown mammal found only in North America, with the face, neck, and shoulders sometimes being slightly gray, and the chest and underside often having irregular white patches. The fisher is classified in the order Carnivora, family Mustelidae, which is a family that also includes weasels, mink, martens, and otters (Service 2016, p. 8). The occurrence of fishers at regional scales is consistently associated with low- to mid-elevation coniferous and mixed conifer and hardwood forests with characteristics of mid- and late-successional forests (e.g., diverse successional stages, moderate to dense forest canopies, large-diameter trees, coarse downed wood, and singular features of large snags, tree cavities, or deformed trees). Throughout their range, fishers are obligate users of tree or snag cavities for denning, and they select resting sites with a high proportion of characteristics of late-successional forests. These characteristics are maintained and recruited in the forest through ecological processes such as fire, insect-related tree mortality, disease, and decay (e.g., Service 2016, pp. 64, 123-124).

Fishers on the west coast of the continent have historically occurred in British Columbia, Washington, Oregon, and California. Fishers native to the west coast in the contiguous United States were historically well distributed in the habitats described above, from the State of Washington south through Oregon, and into northern California and the Sierra Nevada mountains. Subpopulations of these native fishers still occur in northern California/southwestern Oregon and the Sierra Nevada; however, populations of native fishers were extirpated from Washington (Lewis and Hayes 2004, p. 1) and northern Oregon (Aubry and Lewis 2003, pp. 81-82). Recent surveys in the northern Oregon Cascades yielded no fishers (Moriarty et al. 2016, entire), suggesting they remain absent in this area, whereas surveys in the southern Oregon Cascades suggest fisher range may be contracting to the south (Barry 2018, pp. 22-23) relative to where we estimated the fisher's range to be in the southern Oregon Cascades in both 2014 and 2016 (Service 2014 and 2016, entire). Fishers now occurring and reproducing in Washington were established using fishers translocated from outside this three-State region. Fishers from British Columbia were reintroduced to the Olympic Peninsula from 2008 to 2010 (Happe et al. 2017, p. viii), and to the Washington Cascade Range south of Mt. Rainier from 2015 to 2017 (Lewis et al. 2018, p. 5). Reproduction has been documented in both areas. Beginning in 2018, fishers from Alberta were released in the northern Washington Cascades in North Cascades National Park; translocations are expected to continue over the next 2 years in this area, completing planned reintroductions for western Washington (Hayes and Lewis 2006, p. 35).

Fishers were once well distributed throughout their historical range in the habitats described above. Now in Oregon and California, outside of the existing NCSO and SSN known subpopulations in Oregon and California (see figure 2, below), fishers are considered likely extirpated. Additionally, in California, recent survey efforts have not detected fishers south of the reintroduced NSN subpopulation or north of the SSN subpopulation.

Additional information on the species' biology and distribution is described in the final Species Report (Service 2016, pp. 9-12, 25-53).

Summary of Biological Status and Threats

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 is an “endangered species” or a “threatened species.” 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 expected response by the species, 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, and 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 now and in the foreseeable future. In our determination, we correlate the threats acting on the species to the factors in section 4(a)(1) of the Act.

Current Condition of the West Coast DPS of Fisher

Following are brief accounts of the NCSO (and by inclusion the SOC and NSN subpopulations) and SSN subpopulations. Primary threats are introduced in these summaries and described in more detail below in the “Risk Factors for the West Coast DPS of Fisher” section. Additional detail is also found in the “Review of Stressors” section of the final Species Report (Service 2016, pp. 53-162), although we provide updated/new information since 2016 in this document, when applicable. Regulatory and voluntary conservation efforts resulting from the plans and strategies being implemented within both subpopulations were previously described in detail in the 2016 final Species Report, and are updated in this document.

However, as explained in more detail below in the “Existing Regulatory Mechanisms and Voluntary Conservation Measures” section of this rule, we determined that we did not need to evaluate these voluntary conservation efforts under our Policy for Evaluation of Conservation Efforts When Making Listing Decisions (PECE; 68 FR 15100). While it is reasonably likely these conservation efforts will provide some benefit for fishers, we also note that these benefits will be realized at more of an individual fisher/local scale where implemented, and not necessarily at a scale and magnitude sufficient to ameliorate the primary significant threats imperiling the DPS. Therefore, while we acknowledge that the DPS may see conservation benefits from these efforts, we recognize that these benefits will not be sufficient to outweigh the DPS's primary threats, and as such, there is no reason to evaluate these conservation efforts under PECE for certainty of implementation and effectiveness.

NCSO—Northern California-Southwestern Oregon Subpopulation

Abundance information for the NCSO population is presented based on three different geographic portions of this subpopulation. First, the SOC portion west of Crater Lake is predominantly represented by nonnative, reintroduced individuals. However, recent analyses have documented that at least some of these nonnative SOC individuals and native NCSO individuals are overlapping in range, with confirmed interbreeding (Pilgrim and Schwartz 2016, entire; Pilgrim and Schwartz 2017, entire). Second, the NSN portion is represented by native, reintroduced fishers whose genetic stock is from fishers relocated from the Klamath-Siskiyou and Shasta-Trinity subregions (in the historically native NCSO subpopulation) to the northern Sierra Nevada. This geographic portion of the NCSO subpopulation occurs on land known as the SPI Stirling Management Unit in Butte, Plumas, and Tehama Counties, California (Powell et al. 2019, p. 2). Third, the remainder of the native fishers in the NCSO subpopulation occupy the California Coast Range mountains in southern Oregon and northern California, the Klamath-Siskiyou and Shasta-Trinity subregions in northern California, and the western portion of the southern Cascades in northern California.

Fishers in the SOC portion of the NCSO subpopulation stem from a translocation of 30 fishers from British Columbia and Minnesota to the southeastern Cascade Range and west of Crater Lake between 1977 and 1981, after an earlier reintroduction in 1961 failed (Aubry and Lewis 2003, p. 84; Lofroth et al. 2010, pp. 43-44). Based on survey and research efforts starting in 1995, genetic evidence shows these fishers continue to persist (Drew et al. 2003, p. 57; Aubry et al. 2004, pp. 211-215; Wisely et al. 2004, p. 646; Pilgrim and Schwartz 2014-2017, entire; Moriarity et al. 2017, entire; Barry 2018, pp. 6, 22-24). Prior to 2015, survey work in the Oregon Cascades north of the NCSO subpopulation was mainly limited to opportunistic or small-scale efforts. Fishers had not been detected, except for two single fishers: One detected just north of the SOC subpopulation in 2014 (Wolfer 2014, pers. comm.); and a single dispersing juvenile male detected in the same general area in the 1990s (Aubry and Raley 2006, p. 5), suggesting individuals may disperse north through the central Oregon Cascades. Over the winter of 2015-2016, systematic camera surveys occurred in the northern Oregon Cascades (specifically, the southern portion of the Mt. Hood National Forest and northern portion of the Willamette National Forest). No fishers were detected (Moriarty et al. 2016, entire), suggesting fishers may not reach this far north in the Oregon Cascades. Additionally, surveys over the past 3 years have not detected fishers north of the Rogue River in the central Oregon Cascades (Barry 2018, pp. 22-23) (see below).

Information is not available on population size for the SOC portion of the NCSO subpopulation. In the northern portion of the SOC area, fishers were detected in the northern and eastern portions of Crater Lake National Park between 2013 and 2015 (Mohren 2016, pers. comm.). However, systematic surveys were conducted in 2016 and 2017 north and east of Crater Lake National Park and south to the Klamath Falls Resource Area (KFRA; south of the reintroduction area) of the Bureau of Land Management (BLM) Lakeview District (Barry 2018, entire). Few fishers were detected in an area east of Crater Lake National Park where fishers were captured and radio-collared in the early 1990s by Aubry and Raley (2002, entire). Fishers were found on the KFRA, south of where they were previously estimated to occur, and in areas where they were not previously detected (Hayner 2016, pers. comm.). These results suggest that fisher in the SOC area “appears to have contracted, shifted south, or the previous population extent was incorrectly estimated” (Barry 2018, pp. 22-24).

Fishers in the NSN portion of the NCSO subpopulation stem from a 2009 to 2011 translocation of 40 fishers (24 females, 16 males) from Humboldt, Siskiyou, and Trinity Counties, California, to the Sierra Pacific Industries (SPI) Stirling Management Unit in Butte, Plumas, and Tehama Counties, California. Ongoing monitoring has confirmed that fishers born onsite have established home ranges and have successfully reproduced. Trapping efforts in the fall of 2017 as part of ongoing monitoring of the reintroduced subpopulation indicate a minimum of 61 fishers (38 females, 23 males), which is 21 more than were originally introduced (Powell et al. 2019, p. 2).

Older estimates for the NCSO subpopulation (excluding the SOC and NSN reintroduced subpopulations) using various methodologies range from a low of 258-2,850 individuals, based on genetic data (Tucker et al. 2012, pp. 7, 9-10), to a high of 4,018 individuals based on extrapolation of data from two small study areas within the NCSO subpopulation to the entire NCSO subpopulation (Self et al. 2008, pp. 3-5). In 2017, a new estimate was developed for the NCSO subpopulation that includes southern Oregon and coastal California but excludes SOC and NSN (Furnas et al. 2017, pp. 2-3). Furnas et al. (2017) based their estimate of population size on the assumption of a density of 6.6 fishers per 39 mi2 (100 km2) across the area they defined for the NCSO subpopulation (rationale described in detail in Furnas et al. 2017, pp. 12-15). Using this estimate of fisher density, the NCSO subpopulation is estimated to be 3,196 individuals (2,507-4,184; 95 percent Confidence Interval (C.I.)) Furnas et al. 2017, p. 12). With the exception of the reintroduced NSN subpopulation area estimate, which is based on trapping results, Self et al. (2008) and Furnas et al. (2017) base their estimates for the size of the NCSO subpopulation on fisher habitat available prior to 2014.

Trend information for fishers within the NCSO subpopulation is based on the following two long-term study areas. As indicated above, we now consider the NCSO subpopulation to include the areas previously represented as the SOC and NSN reintroduced fisher subpopulations.

(1) The Hoopa study area is approximately 145 mi2 (370 km2) on the Hoopa Valley Indian Reservation north of California State Highway 299 and near Highway 96, which is largely surrounded by the Six Rivers National Forest and other private lands. The study area represents the more mesic portion (containing a moderate amount of moisture) of the NCSO subpopulation area. Fisher studies have been ongoing since 1996. The population trend in the period 2005-2012 indicates declining populations with lambda (population growth rate) of 0.992 (C.I. 0.883-1.100) with a higher lambda rate for females 1.038 (0.881-1.196) than males 0.912 (0.777-1.047) (Higley et al. 2014, p. 102, Higley 2015, pers. comm.).

(2) The Eastern Klamath Study Area (EKSA) is approximately 200 mi2 (510 km2) in size straddling the California/Oregon border. This study area represents the more xeric portion (containing little moisture; very dry) of the NCSO subpopulation area. Monitoring has occurred since 2006 (Green et al. 2018a, entire). The estimate for population growth rate in the period 2006-2013 is increasing (lambda = 1.06; C.I. 0.97-1.15) (Green et al. 2018a, p. 818). However, two years of data collected from 2014-2016 following two large fires in the study area indicate an estimated 40 percent reduction in the number of fishers post-fire (Green et al. 2019, p. 8).

The major habitat-based threats experienced by the NCSO subpopulation are loss of complex canopy forests and den/rest sites, and fragmentation of habitat, from high-severity wildfire, wildfire suppression activities (e.g., backburning, fuel breaks, and snag removal), and vegetation management (e.g., fuels reduction treatments, salvage, hazard tree removal). Major non-habitat related threats are exposure to toxicants and, in some areas, predation. Within the Oregon portion of the NCSO subpopulation, two dead fishers were tested for the presence of rodenticides; exposure was found in both (Clayton 2016, pers. comm.).

In addition to these threats acting on the DPS, there are also several conservation efforts designed to benefit fishers. Such efforts include those being implemented within the portion of the range covered by the Northwest Forest Plan (NWFP), including measures associated with Endangered Species Act section 7 consultations in overlapping northern spotted owl (Strix occidentalis caurina) designated critical habitat. Two principal conservation efforts exist in Oregon. First, there is an intergovernmental Memorandum of Understanding (MOU) for fisher conservation (DOI et al. 2016, entire), which provides a framework for cooperation and achieving mutual fisher conservation goals among Federal and State agencies (Service 2016, pp. 120-121). Second, a template Candidate Conservation Agreement With Assurances (CCAA) for fishers in western Oregon (81 FR 15737, March 24, 2016) requires conservation measures to protect occupied den sites, as well as additional contributions toward a fisher conservation program or work described in the template CCAA. A permit was recently issued under this template CCAA (84 FR 4851, February 19, 2019) and we are in the process of considering five additional permit applications (84 FR 31903, July 3, 2019).

For the portion of the NCSO subpopulation in California, reintroduction efforts have resulted in establishment of a fisher subpopulation in the SPI Stirling Management Area within the NSN (northern Sierra Nevada) with the potential to connect with fishers in the remainder of the NCSO subpopulation to the north. In 2016, an approximately 1.6 million-acre (ac) (647 thousand-hectare (ha)) CCAA for fishers on Sierra Pacific Industries (SPI) ownership in the Klamath, Cascade, and Sierra Nevada mountains was completed (SPI and Service 2016, entire), which incorporated the area and earlier monitoring agreements for the SPI Stirling Management Area CCAA (SPI and Service 2008, entire). Implementation and monitoring has been under way since October 2016. The objectives of this CCAA are to secure general forested habitat conditions for fishers for the 10-year time period and the retention of important fisher habitat components (large trees, hardwoods, and snags) suitable for denning and resting into the future. Additionally, the Green Diamond Forest HCP (GDRC 2018, entire) is anticipated to provide a conservation benefit for fishers and their habitat (portions of forests on the west slope of the coastal and Klamath Mountains) in Del Norte and Humboldt Counties, California. Conservation benefits anticipated include (but are not limited to): Identifying and retaining fisher denning and resting trees, including maintaining a 0.25-mi (402-m) radius no-harvest buffer around active fisher dens; fisher-proofing water tanks and pipes; implementing measures that detect, discourage, and remove unauthorized marijuana cultivation and associated pesticide use; and cooperating with any Federal or State-approved fisher capture and relocation/reintroduction recovery programs (Service 2019a, p. 2).

SSN—Southern Sierra Nevada Subpopulation

The SSN native subpopulation of fisher is small and is geographically separated from the remainder of the DPS. The SSN subpopulation is found in Mariposa, Madera, Fresno, Tulare, and Kern Counties in California. Historically, the subpopulation likely extended farther north, but may have contracted due to unregulated trapping, predator-control efforts, habitat loss and fragmentation, or climatic changes. Today the approximate northern boundary is the Tuolumne River in Yosemite National Park (Mariposa County) and the southern limit is the forested lands abutting the Kern River Canyon, while the eastern limit is the high-elevation, granite-dominated mountains, and the western limit is the low-elevation extent of mixed-conifer forest. Multiple lines of genetic evidence suggest that the isolation of the SSN subpopulation from other subpopulations of native fishers within the West Coast States is longstanding and predates European settlement (Knaus et al. 2011, entire; Tucker et al. 2012, entire; Tucker 2015, pers. comm., pp. 1-2).

Estimates for the SSN subpopulation range from a low of 100 to a high of 500 individuals (Lamberson et al. 2000, entire). A recent estimate of 256 female fishers was based on habitat availability at the time (Spencer et al. 2016, p. 44). Other population estimates are: (1) 125-250 adult fishers based on fisher carrying capacity in currently occupied areas (Spencer et al. 2011, p. 788); and (2) fewer than 300 adult fishers or 276-359 fishers that include juveniles and subadults based on extrapolation from portions of the subpopulation where fishers have been intensely studied to the range of the entire population (Spencer et al. 2011, pp. 801-802). These population estimates are based on habitat conditions for fishers in the Sierra Nevada that predate the ongoing, large-scale tree mortality event in this geographic area that began in approximately 2010. The Sierra tree mortality event is affecting many of the key components of fisher habitat such as complex forest canopy structure and connected closed-canopy forest conditions. Research is currently ongoing to determine to what extent these large-scale habitat changes will have on the SSN subpopulation.

An 8-year monitoring study that sampled an average of 139.5 units (range 90-189) per year during the period 2002-2009 throughout the SSN subpopulation showed no declining trend in occupancy (Zielinski et al. 2013, pp. 3, 10-14; Tucker 2013, pp. 82, 86-91). However, this study had been designed to be run for 10 years while sampling 288 units per year and was intended to have an 80 percent probability of detecting a 20 percent decline over 10 years (Zielinski et al. 2013, p. 11; Tucker 2013, p. 82). As a result of the smaller sample size and shorter duration, the results of this study must be considered inconclusive.

Another study of radio-collared fishers monitored from 2007 through 2014 in the Sugar Pine area (49 mi2 (128 km2)) of the SSN subpopulation showed the survival rate (calculated using demographic parameters) of adult males, but not females, is lower than other subpopulations in the West Coast States. Specifically, Sweitzer et al. (2015a pp. 781-783; 2015b, p. 10) stated that their analysis “suggested slightly negative growth (λ = 0.966) for the period of the research (Table 2). The upper range for λ (1.155) was well above 1.0, however, suggesting stability or growth in some years. The estimated range for λ (Table 2) was consistent with the estimated population densities, which did not indicate a persistent decline during 4 years from 2008-2009 to 2011-2012.” Additionally, in a new report (Purcell et al. 2018) based on fishers studied in the previously mentioned Sugar Pine area, results for radio-collared fishers monitored from 2007 through 2017 (totaling 139 collared fishers) in the Sugar Pine area are updated, indicating an estimated lambda of 0.99 (C.I. 0.826 to 1.104) based on female fisher survival rates (Purcell et al. 2018, pp. 5-6, 17). Specifically, Purcell et al. (2018) stated: “Given the length and intensity of the monitoring associated with calculating these estimates, and the lack of significant difference from zero, the SNAMP/Sugar Pine fisher population appears stable over the study period.” Thus, population growth in the Sugar Pine portion of the SSN subpopulation is estimated to trend less than 1.0; however, the authors suggest that the population in this area is not in persistent decline but is offset by periods of stability or growth (Sweitzer et al. 2015a, p. 784; Purcell et al. 2018, p. 6). Finally, the authors express concern for the subpopulation and the need for continued monitoring (Sweitzer et al. 2015b, p. 10; Purcell et al. 2018, p. 6).

Available population estimates and trend information for the SSN subpopulation does not take into consideration extensive tree mortality that has impacted the habitat since 2015 to present. Research is currently being conducted to determine any potential effects that tree mortality may be having on the SSN fisher subpopulation, but results are not yet available (Green et al. 2019, entire).

The major threats for the SSN subpopulation are loss and fragmentation of habitat resulting from high-severity wildfire and wildfire suppression activities, vegetation management, and forest insects and tree diseases, as well as direct impacts that include high mortality rates from predation, exposure to toxicants, and potential effects associated with small population size. Tree mortality may be an additional threat on this subpopulation given the species' needs, but more information is necessary to determine population-level impacts. Potential conservation measures include the development of the Southern Sierra Nevada Fisher Conservation Strategy (Spencer et al. 2016, entire).

Risk Factors for the West Coast DPS of Fisher

Potential threats currently acting upon the West Coast DPS of fisher or likely to affect the species in the future are evaluated and addressed in the final Species Report (Service 2016, pp. 53-162). We consider these threats in light of the statutory factors identified in the Act, including: (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. The reader is directed to the Species Report (Service 2016, entire) for a more detailed discussion of the threats summarized in this document (http://www.fws.gov/​cno/​fisher/​). However, please note that our most recent consideration of new data since 2016 coupled with our reevaluation of the entirety of the best available scientific and commercial information is represented and summarized in this revised proposed rule.

Our analysis represents an evaluation of the biological status of the species, based upon our assessment of the cumulative impact of all effects anticipated from the identified threats, and how that cumulative impact may affect the species' continued existence currently and in the future. We used the best available scientific and commercial data, and the expert opinions of the analysis team members. Based on the analysis and discussion contained herein, in this document we evaluated potential habitat-based threats including high-severity wildfire, wildfire suppression activities, and post-fire management actions; climate change; forest insects and tree diseases; vegetation management; and human development (Factor A). We also evaluated potential threats related to direct mortality of fishers including trapping and incidental capture (Factor B), research activities (Factor B), disease or predation (Factor C), collision with vehicles (Factor E), exposure to toxicants (Factor E), and potential effects associated with small population size (Factor E). Finally, we also evaluated the inadequacy of existing regulatory mechanisms (Factor D).

The timing (immediacy) of each threat was assessed independently based upon the nature of the threat and time period that we can be reasonably certain the threat is acting on fisher populations or their habitat. In general, we considered that the trajectories of the threats acting on fisher subpopulations across the DPS's range could be reasonably anticipated over the next 35-40 years. We estimated this timeframe as a result of our evaluation of an array of time periods used in modeling. For example, climate models for areas with fisher habitat, habitat conservation plans (HCPs), and timber harvest models generally predict 50 to 100 years into the future, and forest planning documents often predict over shorter timeframes (10 to 20 years). We considered 40 years at the time of the 2014 Proposed Rule, and given the 5-year time period since, we are modifying the foreseeable future time period to a range of 35-40 years. This is a timeframe that we can reasonably determine that both the future threats and the species' responses to those threats are likely. This time period extends only so far as the predictions into the future are reliable, including a balance of the timeframes of various models with the types of threats anticipated during the 35- to 40-year time period.

As we conducted our threats analysis, we determined that the most significant drivers of the species' future status were: Wildfire and wildfire suppression, damage to forest health from disease and insect infestations, and the potential for climate change to exacerbate both of these threats, as well as the threats related to vegetation management and exposure to toxicants. While our assessment of the species' status was based on the cumulative impact of all identified threats, as explained above, we are only presenting our analyses on these specific primary threat drivers for the purposes of this revised proposed rule. Full detailed analyses for all the other individual threats, we refer the reader to the Species Report (Service 2016, entire).

Wildfire and Wildfire Suppression

Our evaluation includes both the effects of wildfire on fisher habitat as well as those activities associated with wildfire suppression that may result in changes to fisher habitat (for example, backburning, fuel breaks, and snag removal). Naturally occurring fire regimes vary widely within the range of fishers on the West Coast (Service 2014, p. 58). Potential for high-severity wildfire to affect fisher habitat and fisher populations is concentrated in northern California-southwestern Oregon and the Sierra Nevada areas as compared to the remainder of the fisher's historical range in the West Coast States (Service 2014, pp. 62-63). In general, high-severity wildfire has the potential to remove suitable fisher habitat by removing forest canopy, large trees, and structurally diverse understories, which can take from decades to a century or more to regrow, depending on the habitat feature (Service 2014, pp. 59-60). Mixed-severity wildfire includes patches of low-severity wildfire and patches of high-severity wildfire (Jain et al. 2012, p. 47).

At the landscape scale, mixed-severity wildfire effects to fisher habitat may only affect an area's ability to support fishers for a short period of time due to the patchy nature of burned and unburned areas. Additionally, a beneficial aspect of mixed-severity wildfires (as opposed to just high-severity wildfires) is that these wildfires may contribute to the regeneration of the hardwood component of mixed-conifer forest used by fisher (Cocking et al. 2012, 2014, entire). Low-severity wildfire may reduce some elements of fisher habitat temporarily, but also helps to contribute to the ecological processes necessary to create tree cavities essential for denning and resting fishers (Weir et al. 2012, pp. 237-238). Low-severity wildfire is unlikely to remove habitat, and post-wildfire areas are likely to still be used by fishers (Naney et al. 2012, p. 6; Truex and Zielinski 2013, p. 90).

Within shrub, grassland, and forested lands across the western United States (including the Sierra Nevada, southern Cascades, and Coast ranges), the wildfire season length increased over each of the last 4 decades, from 65 days in the 1970s to 140 days in the 2000s (Westerling 2016, pp. 3, 8, and 10). The lengthening of the wildfire season is largely due to declining mountain snowpack and earlier spring snowmelt, which contributes to a decrease in vegetation moisture that enables more frequent large wildfires and an increase in the total area burned (Westerling 2016, pp. 8-9). In the SSN subpopulation area, changes in climate are associated with large increases in the area burned by wildfire (Dettinger et al. 2018, p. 72), and increases in the frequency of large wildfires greater than 24,700 (ac) (9,996 (ha) (Westerling 2016, pp. 6-7). Recent publications on wildfire occurrence and severity within the NCSO and SSN fisher subpopulations have not changed our conclusions about this threat from the 2014 Proposed Rule (79 FR 60419, October 7, 2014; p. 60429).

Recent information on fishers' behavioral and localized population response to wildfires is available for both the NCSO and SSN fisher subpopulations, as shown below.

Northern California-Southern Oregon (NCSO)

In a monitored fisher population in the Klamath-Siskiyou area, declines in the overall fisher population occurred after wildfires in the study area in 2014 and 2015 (Green et al. 2019, entire). This population of fishers was monitored for 8 years pre-wildfire and the population was considered relatively stable. The decline in the number of fishers due to the wildfires is 40 percent, a decrease that became apparent the first full year following the fires and has persisted for at least 2 more years (Green et al. 2019, p. 8). Fisher densities declined across all wildfire severity types but declined the most in areas with more than a 50 percent loss of tree basal area (Green et al. 2019, p. 6).

Within the Biscuit Fire area in southwest Oregon, which burned in 2002, surveys conducted in 2016 and 2017 did not detect fishers within the burn perimeter (Barry 2018, pp. 22-23), suggesting fishers may not yet occupy the area. The Biscuit Fire appears to have been unusually large and severe for the Klamath-Siskiyou region based on estimates of crown damage (Odion et al. 2004, p. 932) and area affected by surface fire (Thompson and Spies 2009, pp. 1,692-1,693).

To update our 2014 analysis of wildfire effects within the NCSO subpopulation, we conducted an analysis similar to the one completed for the 2014 draft Species Report (Service 2014, pp. 62-64; Service 2019b, unpublished data). Using the fisher habitat map developed for the 2014 Proposed Rule and U.S. Forest Service data for burn severity for 2008-2018 (USDA Forest Service 2019), we estimated the effects of high-severity wildfire to fisher habitat over the past 10 years. We assumed wildfires that burned at high severity (greater than 50 percent basal area loss) changed fisher habitat to a condition that would not be selected by fishers; this assumption was based on the recent results as reported in Green et al. (2019a, p. 6). Overall, high and intermediate quality fisher habitats in the NCSO subpopulation have decreased by 526,424 ac (213,036 ha) from 7,050,035 ac (2,853,047 ha) to 6,523,610 ac (2,640,011 ha), or approximately 7 percent, as a result of wildfires since 2008. The total area assessed was approximately 10,459,612 ac (4,232,855 ha).

For comparison purposes, in our 2014 draft Species Report, we estimated 4 to 8 percent of fisher habitat would be lost over the next 40 years due to high-severity wildfire (Service 2014, p. 64). Our 2014 area of analysis for the NCSO subpopulation was based on fire data from 1984 to 2011 and assessed approximately 24,080,693 ac (9,745,111 ha). The results of our new analysis is based on fire data from the period 2008 to 2018, a 10-year period of actual data, which indicates our earlier estimates of changes to fisher habitat from wildfire over the next 40 years may have been an underestimate.

Southern Sierra Nevada (SSN)

In an analysis of a portion of the SSN fisher subpopulation, fisher occupancy of sample units trends lower among those units burned by either prescribed burning or wildfire (Sweitzer et al. 2016, pp. 218-220); nonetheless, the overall results of this analysis did not include a consistent negative effect of fire on fisher habitat use. Results of modeling the variables of forest structure important to fishers for denning habitat on the Sierra National Forest and Yosemite National Park suggest that suitable denning habitat is maintained in burned forests, though primarily those with low-severity wildfire conditions (Bomdahl 2018, entire). Fisher behavior in post-wildfire landscapes in the French (2014) and Aspen Fires (2013) indicated an avoidance of areas affected by high- and moderate-severity wildfires, and a higher probability of being found in ravines or canyon bottoms in combination with unburned or lightly burned patches (Thompson et al. 2019, pp. 13-14). This new information differs from that reported in our final Species Report (Service 2016, p. 66) and may be due to different scales of analysis, the values chosen to identify wildfire severity classes, or the 2-4 year vs. 10-year post-wildfire sampling period (Hanson et al. 2013, entire; Thompson et al. 2019, pp. 15-18). Without demographic data on age class, survival, or reproduction, it is difficult to say with certainty whether fisher use of post-wildfire landscapes is for dispersal or whether such areas act as population sinks, as has been identified for the proposed coastal DPS of Pacific marten (Martes caurina) (Thompson et al. 2019, pp. 17-18).

For comparison purposes based on data compiled for a new analysis of effects of wildfire on fisher habitat in the southern Sierra Nevada, the Conservation Biology Institute (CBI) analyzed high severity fire data from 2003 to 2017 (CBI 2019, pp. 26-28). This new analysis shows a loss of fisher denning, resting, and foraging habitat of approximately 25 percent over the time period 2003-2017, with most of that loss occurring between 2013 and 2017 (approximately 22 percent) (CBI 2019, p. 28). In addition, the wildfires occurring on the Sierra and Sequoia National Forests bisected and disrupted connectivity between—or reduced the overall size of—key core areas as identified in the SSN fisher conservation strategy (Spencer et al. 2016, p. 10; CBI 2019, pp. 26-28).

Wildfire and Wildfire Suppression Summary

When considering the best available scientific and commercial information regarding wildfire and wildfire suppression activities (including new information since the time of the 2014 Proposed Rule and our reevaluation of peer reviewer and other comments received), we maintain that wildfire is a natural ecological process. As stated above, wildfire may be increasing in terms of frequency, severity, and magnitude in California and southern Oregon. We acknowledge there is debate concerning whether wildfire severity is increasing (Mallek et al. 2013, pp. 11-17; Stephens et al. 2015, pp. 12-16; Hanson and Odion 2016, pp. 12-17; Odion et al. 2016, entire). Our best professional judgment leads us to conclude that if the severity and extent of wildfires are such that substantial areas of canopy and large trees are lost, multiple decades of forest growth and structural development would be necessary for those burned areas to support fisher reproduction. Alternatively, if wildfire severity is low or mixed, important habitat elements to fisher (e.g., den trees) can be both created and removed within a home range such that the burned habitat may continue to support both fisher foraging and reproduction. Therefore, based on the research and data currently available (as described above and in Service 2014, p. 64; Sequoia Forest Keeper 2019, pers. comm.; Spencer et al. 2016, p. 10), we believe that, in areas where wildfires remove 50 percent or more of the basal area of trees in the habitats fisher select (high and intermediate quality), fisher occupancy and reproduction is negatively affected. In areas where less than 50 percent of the basal area is lost, the degree to which wildfire (and wildfire suppression activities) affects fisher populations depends on the forest type, landscape location, size, and intensity of the wildfire.

Climate Change

At the time of the 2014 Proposed Rule, we stated and reaffirm here that, overall, fisher habitat is likely to be affected by changing climate conditions, but the severity will vary, potentially greatly, among different regions, with effects to fishers ranging from negative, neutral, or potentially beneficial. Climate change is likely to alter the structure and tree species composition of fisher habitat, and also result in changes to habitat of prey communities and ultimately prey availability. Studies of climate change present a range of effects including some that indicate conditions could remain suitable for fisher, and others that indicate a reduction in habitat quality or suitability could lead to increased chronic stress of fishers. Climate throughout the West Coast States is projected to become warmer over the next century, and in particular, summers will be hotter and drier, with heat waves that are more frequent (Hayhoe et al. 2004, p. 12,423; Tebaldi et al. 2006, pp. 191-200; Mote and Salathé 2010, p. 41; Salathé et al. 2010, p. 69; Cayan et al. 2012, pp. 4, 10; Mote et al. 2013, p. 34; Pierce et al. 2013, pp. 844, 848).

  • In Oregon, Dalton et al. (2017, pp. 4, 8) evaluated greenhouse gas emissions via global climate models with future emission pathways called “representative concentration pathways” (RCPs). They considered multiple greenhouse gas emission scenarios, including low (RCP 4.5) and business-as-usual (RCP 8.5). Their analysis indicates that extreme heat events are expected to increase in frequency, duration, and intensity by the 2050s due to warming temperatures (RCP 4.5 = mean annual temperature increase predicted on average 3.6 degrees Fahrenheit (°F); RCP 8.5 = mean annual temperature increase predicted on average 5.0 °F). Summers are expected to warm more than the annual average and likely to become drier. Annual precipitation is projected to increase slightly, although with a high degree of uncertainty. Extreme heat and precipitation events are expected to increase in frequency, duration, and intensity.
  • In California, information from Pierce et al. (2013) and Safford et al. (2012) used multiple general circulation models and downscaling with regional climate models to develop probabilistic projections of temperature and precipitation changes over California by the 2060s. Predictions indicate an annual mean temperature increase of 4.3 °F (2.4 degrees Celsius (°C)) by 2060 (Pierce et al. 2013, p. 844), which falls in line with already increased temperatures of around 1 to 2.5 °F (0.5 to 1.4 °C) over the past 75 to 100 years specifically in the Sierra Nevada (Safford et al. 2012, p. 25). In the Klamath Mountains portion of the NCSO subpopulation area, precipitation is likely to fall increasingly as rain rather than snow, becoming mainly rain-dominated by mid-century (Dalton et al. 2017, p. 17).

Higher temperatures during spring and summer, coupled with early snow melt, will reduce moisture of both live fuels and dead surface fuels by increasing evaporative demands during the dry season (Kelly and Syphard 2016, pp. 2-3). Additionally, annual precipitation changes have been and are likely to continue to be inconsistent across California (Polade et al. 2017, p. 1), as well as the remainder of the West Coast States.

Studies specific to predicting the effects of climate change on suitable fisher habitat have produced a wide range of results. Ecotype conversion to woodland, shrubland, or grassland would result in the loss of suitable fisher habitat. This type of shift is predicted, for example, in the southern Sierra Nevada (Gonzalez et al. 2010, fig. 3; Lawler et al. 2012, p. 388). On the other hand, shifts from conifer forest to hardwood-dominated mixed forest in the southern Sierra Nevada or Klamath region could either increase or decrease available habitat to fishers (Lawler et al. 2012, pp. 384-386; Loarie et al. 2008, p. 4 and fig. 4). Given the contribution of hardwood trees to fisher habitat in drier parts of the NCSO and SSN subpopulations, a shift to increasing hardwoods in the more coastal or higher elevation forest types could improve habitat. However, trees are long-lived and mature forests can persist under suboptimal conditions, preventing better-suited vegetation from becoming established until disturbance removes the original forest (Sheehan et al. 2015, p. 27). Consequently, the increase in the hardwood component of fisher habitat in predominantly conifer areas may not occur until after fires have removed enough of the existing stand to allow hardwood establishment, potentially decreasing suitable habitat in the interim.

Other studies suggest that climate change will adversely impact forest habitat by intensifying large-scale, high-severity wildfire, drought, and tree mortality (Kadir et al. 2013, pp. 132, 137; Westerling 2016, pp. 1-2; Stephens et al. 2018, p. 77). A wide range of assumptions and caveats typically accompanies these types of predictions.

Variables predicting fisher resting habitat as described by Zielinski and Gray 2018 (p. 903) include stand characteristics such as canopy closure, basal area of conifer and hardwood trees, and diameter and age of dominant conifers. To date climate change has not significantly affected resting habitat for fishers, which, according to Zielinski and Gray (2018, pp. 899, 903), has remained stable over the past 20 years across the California-portion of the DPS's range, although habitat suitability tended to be lower on private lands than public lands. However, when considering resting habitat trends over these 20 years to help us project potential future resting habitat conditions in light of climate change projections, survey data in the Eldorado and Sierra National Forests (within a portion of the SSN subpopulation area) indicate the beginning of a negative trend in resting habitat suitability (Zielinski and Gray 2018, p. 903), whereas resting habitat examined within the NCSO subpopulation area varied greatly (i.e., suitable resting habitat decreased in the Shasta-Trinity National Forest, increased in the Six Rivers National Forest, and remained unchanged over time for both the Klamath and Mendocino National Forests).

In addition to the potential climate change effects to fisher habitat discussed above, some researchers have suggested climate change may cause direct effects to fishers, including increased mortality, decreased reproductive rates, alterations in behavioral patterns, and range shifts. Fishers may be especially sensitive, physiologically, to warming summer temperatures (Zielinski et al. 2004, p. 488; Slauson et al. 2009, p. 27; Facka 2013, pers. comm.; Powell 2013, pers. comm.). As a result, researchers (e.g., Burns et al. 2003, Zielinski et al. 2004, Lawler et al. 2012, Olson et al. 2014) theorize that fishers likely will either alter their use of microhabitats or shift their range northward and upslope, in order to avoid thermal stress associated with increased summer temperatures.

Although we indicated in the 2014 Proposed Rule that climate change is not viewed as a direct threat to fishers or their habitat, the best available information indicates there is a link between changing climate conditions (temperature and precipitation changes, more frequent and prolonged droughts) and the resulting changes to overall habitat suitability and availability for fishers throughout their range, as well as potential to increase fisher stress levels when habitat changes occur. These changes more specifically affect the amount and distribution of habitat necessary for female fishers to be able to have places to den and raise their young. For example:

  • Climate change, wildfire, and air quality: Ongoing climate change in California is likely to result in significant or amplified wildfire activity and air quality challenges, with area burned and severity likely to increase (Hurteau et al. 2019, pp. 1, 3; Moritz et al. 2018, p. 36). This in turn can result in reduced denning habitat availability for fishers, such as in the Coast Range and Klamath Mountains portion of the NCSO subpopulation area, which is projected to experience wildfire return intervals decreased by half and thus result in a near tripling of the annual area burned in this century compared to last (Sheehan et al. 2015, pp. 20-22; Dalton et al. 2017, p. 46).
  • Drought, tree mortality, and wildfire: With increased drought conditions, tree mortality and large-scale high-severity wildfire are likely to increase in frequency and size, especially if fuel loads in forests are not decreased (Young et al. 2017, p. 78; Westerling and Bryant 2008, pp. S244-S248; Abatzoglou and Williams 2016, pp. 11,770, 11,773). The loss of adequate forest canopy cover to provide habitat suitable for denning female fishers is occurring due to tree mortality as a result of drought and wildfire (CBI 2019, p. 9).

With regard specifically to droughts: Although we can expect that future droughts may be more intense, it is unknown whether or not droughts in the future will be worse than our worst droughts in the past (Keeley and Syphard 2016, p. 6). Regardless, it appears that climate change is exacerbating the effects of drought, given that changing climate conditions are estimated to have contributed 5 to 18 percent to the severity of one of the worst recent droughts in 20th-century California history (Keeley and Syphard 2016, p. 6).

  • Climate change, wildfire, disease, tree mortality: The observed increases in wildfire activity in Oregon are partially due to climate change; increasing wildfire activity is expected under future warming, which in turn can exacerbate tree mortality from agents such as mountain pine beetles (Dalton et al. 2017, p. 46). Tree mortality (whether from changing climate conditions or any other factor), in turn, is likely to result in fishers experiencing reduced fitness (a positive relationship between higher amounts of tree mortality and higher cortisol levels in fishers), as documented in one portion of the SSN subpopulation (Kordosky 2019, pp. 14, 36) and an overall reduction in forest stand conditions known to be suitable denning habitat (CBI 2019, en