Endangered and Threatened Wildlife and Plants; Removing the Apache Trout From the List of Endangered and Threatened Wildlife
| Published date | 11 August 2023 |
| Record Number | 2023-15689 |
| Citation | 88 FR 54548 |
| Court | Fish And Wildlife Service |
| Section | Proposed rules |
Federal Register, Volume 88 Issue 154 (Friday, August 11, 2023)
[Federal Register Volume 88, Number 154 (Friday, August 11, 2023)]
[Proposed Rules]
[Pages 54548-54564]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-15689]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R2-ES-2022-0115; FF09E22000 FXES1113090FEDR 234]
RIN 1018-BG94
Endangered and Threatened Wildlife and Plants; Removing the
Apache Trout From the List of Endangered and Threatened Wildlife
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service or USFWS),
propose to remove the Apache trout (Oncorhynchus apache), a fish native
to Arizona, from the Federal List of Endangered and Threatened Wildlife
due to recovery. Our review of the best available scientific and
commercial data indicates that the threats to the species have been
eliminated or reduced to the point that the species no longer meets the
definition of a threatened species or an endangered species under the
Endangered Species Act of 1973, as amended (Act). If we finalize this
rule as proposed, the prohibitions and conservation measures provided
by the Act, particularly through section 7 and our regulations would no
longer apply to the Apache trout. We request information and comments
from the public regarding this proposed rule for the Apache trout.
DATES: We will accept comments received or postmarked on or before
October 10, 2023. 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
[[Page 54549]]
must receive requests for public hearings, in writing, at the address
shown in FOR FURTHER INFORMATION CONTACT by September 25, 2023.
ADDRESSES: You may submit comments on this proposed rule by one of the
following methods:
(1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R2-ES-2022-0115,
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-R2-ES-2022-0115, 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: This proposed rule and
supporting documents (including the species status assessment (SSA)
report, references cited, and 5-year review) are available at https://www.regulations.gov under Docket No. FWS-R2-ES-2022-0115.
FOR FURTHER INFORMATION CONTACT: For questions related to the SSA
report and associated literature cited: Jess Newton, Project Leader,
Arizona Fish and Wildlife Conservation Office, U.S. Fish and Wildlife
Service, 2500 S Pine Knoll Drive, Flagstaff, AZ 86001; telephone 928-
556-2140.
For questions related to this proposed rule and other supporting
documents: Heather Whitlaw, Field Supervisor, Arizona Ecological
Services Office, U.S. Fish and Wildlife Service, 9828 North 31st Ave.
#C3, Phoenix, AZ 85051-2517; telephone 602-242-0210.
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.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Act, a species warrants
delisting if it no longer 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 endangered in the
foreseeable future throughout all or a significant portion of its
range). The Apache trout is listed as threatened, and we are proposing
to delist it. We have determined the Apache trout does not meet the
Act's definition of an endangered or threatened species. Delisting a
species can be completed only by issuing a rule through the
Administrative Procedure Act rulemaking process (5 U.S.C. 551 et seq.).
What this document does. This action proposes to remove the Apache
trout from the List of Endangered and Threatened Wildlife due to the
species' recovery.
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. The determination to delist a species must be
based on an analysis of the same factors.
Under the Act, we must review the status of all listed species at
least once every five years. We must delist a species if we determine,
on the basis of the best available scientific and commercial data, that
the species is neither a threatened species nor an endangered species.
Our regulations at 50 CFR 424.11 identify three reasons why we might
determine a species shall be delisted: (1) The species is extinct; (2)
the species does not meet the definition of an endangered species or a
threatened species; or (3) the listed entity does not meet the
definition of a species. Here, we have determined that the Apache trout
does not meet the definition of an endangered species or a threatened
species and, therefore, we are proposing to delist it.
Information Requested
We intend that any final action resulting from this proposal 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 or State agencies, Native
American Tribes, the scientific community, industry, or other
interested parties concerning this proposed rule.
We particularly seek comments concerning:
(1) Reasons why we should or should not remove the Apache trout
from the List of Endangered and Threatened Wildlife (i.e., ``delist''
the species);
(2) New biological or other relevant data concerning any threat (or
lack thereof) to this fish (e.g., those associated with climate change
or nonnative trout);
(3) New information on any efforts by the State or other entities
to protect or otherwise conserve the Apache trout or its habitat;
(4) New information concerning the range, distribution, and
population size or trends of this fish; and
(5) New information on the current or planned activities in the
habitat or range of the Apache trout that may adversely affect or
benefit the fish.
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,
[[Page 54550]]
will be available for public inspection on https://www.regulations.gov.
Because we will consider all comments and information we receive
during the comment period, our final determination may differ from this
proposal. For example, based on the new information we receive (and any
comments on that new information), we may conclude that the species
should remain listed as threatened, or we may conclude that the species
should be reclassified from threatened to endangered.
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 location 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).
Peer Review
A species status assessment (SSA) team prepared an SSA report for
the Apache trout. The SSA team was composed of Service biologists, in
consultation with other species experts from White Mountain Apache
Tribe (WMAT), Arizona Game and Fish Department (AZGFD), U.S. Forest
Service (USFS), and Trout Unlimited. 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 of
listing actions under the Act, we solicited independent scientific
review of the information contained in the SSA report. We sent the SSA
report to three independent peer reviewers and received responses from
all three peer reviewers. Results of this structured peer review
process can be found at https://regulations.gov. In preparing this
proposed rule, we incorporated the results of the peer reviews, as
appropriate, into the final SSA report, which is the foundation for
this proposed rule.
Summary of Peer Reviewer Comments
As discussed in Peer Review above, we received comments from three
peer reviewers on the draft SSA report. We reviewed all comments
received from three peer reviewers for substantive issues and new
information regarding the information contained in the SSA report. The
peer reviewers generally concurred with our methods and conclusions and
did not provide additional information for inclusion in the report. We
considered one of these comments to be substantive, which we summarize
below.
Comment: A reviewer commented that: (1) only future scenario 3 (the
status quo scenario) is likely to occur; and (2) further consideration
should be given to Apache trout resiliency within future scenarios
given the impacts of climate change.
Our Response: We retained all five future conditions scenarios in
the SSA report because we concluded that they cover the entire range of
plausible outcomes for the Apache trout given the possible levels of
conservation management. For our status determination in this proposed
rule we evaluated the two scenarios that we consider to be plausible
given the completion of the cooperative management plan (CMP) and
current commitments to ongoing species management. We recognize the
seriousness of impacts to Apache trout related to climate change and
conducted thorough analyses on the possible effects on Apache trout
resiliency from warmer stream temperatures, more frequent and severe
droughts, increased risk of wildfire and post-fire debris flow,
decrease in snowpack but increased rain on snow events, and more
intense summer monsoon rains. These analyses are presented in the SSA
report and we incorporated them into our future scenarios. Therefore,
we conclude that the SSA report adequately addresses consideration of
the potential effects of climate change in our analysis of resiliency
within the future scenarios.
Previous Federal Actions
The Apache trout was listed as endangered under the Endangered
Species Preservation Act in 1967 (32 FR 4001; March 11, 1967) due to
threats from overexploitation, habitat degradation (e.g., mining and
agricultural development), hybridization with nonnative salmonids, and
predation by species such as the brown trout (Salmo trutta). The
species was subsequently downlisted to threatened under the Act in 1975
(40 FR 29863; July 16, 1975) after successful culturing in captivity
and discovery of additional populations. The 1975 downlisting rule
included a 4(d) rule that allows AZGFD to establish and regulate sport
fishing opportunities on non-Tribal lands. The WMAT regulates take and
sport fishing for Apache trout on the Fort Apache Indian Reservation.
There is no critical habitat designation for the Apache trout because
listing and reclassification occurred before the 1978 and 1982
amendments to the Act that provide for critical habitat designation.
The first recovery plan for the Apache trout was finalized in 1979
(USFWS 1979, entire), and a revised plan was finalized in 1983 (USFWS
1983, entire). A second revision was completed in 2009 (USFWS 2009,
entire).
A 5-year review for Apache trout was completed in 2010 (USFWS 2010,
entire). While recognizing that many of the threats identified in the
recovery plan had been addressed, the persistence of certain threats
(such as the invasion by nonnative trout into Apache trout habitat)
resulted in a recommendation of ``No change'' in the species' status
(USFWS 2010, p. 4). On May 5, 2021, we published a notice in the
Federal Register (86 FR 23976) announcing the initiation of 5-year
status reviews and information requests for 23 species, including the
Apache trout. On August 29, 2022 (USFWS 2022a, entire), a 5-year review
of the Apache trout status was completed. This latest 5-year review
concludes that the status of the Apache trout has substantially
improved since the time of the species' listing and recommends that the
Apache trout be considered for delisting due to recovery.
Background
A thorough review of the biological information on the Apache trout
including taxonomy, life history, ecology, and conservation activities,
as well as threats facing the species or its habitat is presented in
our SSA report (USFWS 2022b, entire) and the revised Recovery Plan for
Apache trout (USFWS 2009, entire), which are available at https://www.regulations.gov under Docket No. FWS-R2-ES-2022-0115. The following
is a summary of the best available information on Apache trout.
The Apache trout is a salmonid species endemic to the White
Mountains region of east-central Arizona. The species is currently
found in the White River, Black River, and the Little Colorado River
drainages in the
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White Mountains of east-central Arizona, although the historical
distribution is not known with certainty. Apache trout occupies
headwater streams upstream of natural and conservation barriers, which
likely reflects a truncated distribution from historical distributions
due to nonnative trout, habitat alterations, and other factors (USFWS
2009, pp. 1, 6-16). Distinguishing characteristics of Apache trout
include a fusiform (spindle-shaped) body and large dorsal fin, with
spots on the body pronounced and often uniformly spaced both above and
below the lateral line. Spots are circular in outline, are medium-
sized, and appear slightly smaller than most interior subspecies of
cutthroat trout (Oncorhynchus clarkii) but more like typical cutthroat
trout than Gila trout (O. gilae) (Miller 1972, pp. 410-411). Yellow or
yellow-olive colors predominate, with tints of purple and pink
observable on live specimens. Two black spots are located horizontally
on the eye before and aft of the pupil, creating the image of a black
band through the eye. A red or pink lateral band is usually absent
(Miller 1972, p. 414). Dorsal, pelvic, and anal fins have conspicuous
cream or yellowish tips. Like most trout occupying small headwater
streams, the Apache trout has been described as an opportunistic
feeder, primarily feeding on various species of insects such as
caddisflies (Trichoptera), mayflies (Ephemeroptera), stoneflies
(Plecoptera), and beetles (Coleoptera) (Harper 1978, p. 108).
Recovery Planning and Recovery Criteria
Section 4(f) of the Act directs us to develop and implement
recovery plans for the conservation and survival of endangered and
threatened species unless we determine that such a plan will not
promote the conservation of the species. Under section 4(f)(1)(B)(ii),
recovery plans must, to the maximum extent practicable, include
objective, measurable criteria which, when met, would result in a
determination, in accordance with the provisions of section 4 of the
Act, that the species be removed from the List.
Recovery plans provide a roadmap for us and our partners on methods
of enhancing conservation and minimizing threats to listed species, as
well as measurable criteria against which to evaluate progress towards
recovery and assess the species' likely future condition. However, they
are not regulatory documents and do not substitute for the
determinations and promulgation of regulations required under section
4(a)(1) of the Act. A decision to revise the status of a species, or to
delist a species is ultimately based on an analysis of the best
scientific and commercial data available to determine whether a species
is no longer an endangered species or a threatened species, regardless
of whether that information differs from the recovery plan.
There are many paths to accomplishing recovery of a species, and
recovery may be achieved without all criteria being fully met. For
example, one or more criteria may be exceeded while other criteria may
not yet be met. In that instance, we may determine that the threats are
minimized sufficiently, and that the species is robust enough that it
no longer meets the definition of an endangered species or a threatened
species. In other cases, we may discover new recovery opportunities
after having finalized the recovery plan. Parties seeking to conserve
the species may use these opportunities instead of methods identified
in the recovery plan. Likewise, we may learn new information about the
species after we finalize the recovery plan. The new information may
change the extent to which existing criteria are appropriate for
identifying recovery of the species. The recovery of a species is a
dynamic process requiring adaptive management that may, or may not,
follow all the guidance provided in a recovery plan.
The Apache trout recovery plan identified two major areas of focus
to achieve the long-term survival and viability of the species:
protection of Apache trout habitat from various watershed alteration
activities (e.g., forestry, livestock grazing, reservoir construction,
agriculture, road construction, and mining) and protection from
introduction of nonnative trout species that have resulted in
hybridization, competition, and predation (USFWS 2009, p. v). In order
to achieve recovery, the recovery plan identified criteria that will
assist in determining whether the Apache trout has recovered to the
point that the protections afforded by the Act are no longer needed.
These criteria are:
(1) Habitat sufficient to provide for all life functions at all
life stages of 30 self-sustaining, discrete populations of pure Apache
trout has been established and protected through plans and agreements
with responsible land and resource management entities. These plans
will address and serve to remedy current and future threats to Apache
trout habitat.
(2) Thirty discrete populations of genetically pure Apache trout
have been established and determined to be self-sustaining. A
population will be considered self-sustaining by the presence of
multiple age classes and evidence of periodic natural reproduction. A
population will be considered established when it is capable of
persisting under the range of variation in habitat conditions that
occur in the restoration stream.
(3) Appropriate angling regulations are in place to protect Apache
trout populations while complying with Federal, State, and Tribal
regulatory processes.
(4) Agreements are in place between the Service, AZGFD, and WMAT to
monitor, prevent, and control disease and/or causative agents,
parasites, and pathogens that may threaten Apache trout.
Recovery Plan Implementation
The following discussion summarizes the recovery criteria and
information on recovery actions that have been implemented under each
delisting criterion.
Delisting Criterion 1: Habitat sufficient to provide for all life
functions at all life stages of 30 self-sustaining, discrete
populations of pure Apache trout has been established and protected
through plans and agreements with responsible land and resource
management entities. This criterion has been met. Since the time of
listing, the Service, in collaboration with WMAT, AZGFD, USFS, and
Trout Unlimited, have worked to maintain and restore riparian habitats
where the Apache trout occurs. Multiple age classes are represented
across the populations, which are indicative of healthy recruitment and
stable populations from year to year. Although the average abundance of
adults is fewer than 500 within most populations, the diversity of age
classes suggests healthy survival and recruitment rates. Furthermore,
adult individuals make up a significant share of the overall
population, which is indicative that many fry and juveniles are able to
survive to adulthood without the need of restocking from adjacent
populations or hatcheries.
The habitat of Apache trout is managed, and land-use impacts on the
species are reduced through environmental review of proposed projects.
For example, the Apache-Sitgreaves National Forests (ASNF) Land
Management Plan incorporates desired conditions for aquatic habitats to
contribute to the recovery of federally listed species and to provide
self-sustaining populations of native species (ASNF 2015, pp. 16-26).
WMAT also has land management plans that help protect Apache trout
populations. Alteration of logging practices, road
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closure and removal, and ungulate exclusion through fencing or retiring
allotments have all been used to manage Apache trout habitat on the
ANSFs and Fort Apache Indian Reservation (Robinson et al. 2004, p. 1;
USFWS 2009, pp. 23-29).
Delisting Criterion 2: Thirty discrete populations of genetically
pure Apache trout have been established and determined to be self-
sustaining. This criterion has almost been met. Compared to the time of
listing when we identified 14 genetically pure populations, currently,
the Apache trout consists of 29 genetically pure populations and one
population that is suspected to be genetically pure. These populations
are comprised of both relict and replicate populations. A relict
population of Apache trout is one that was originally discovered in a
stream within the historical range of the species and is the species'
original genetic stock. A replicate population of Apache trout is one
that was established using individuals from a relict population or
another replicate population that represents a relict genetic lineage.
Replicate populations are usually established within the historical
range of the species, including streams that were originally unoccupied
by Apache trout and streams where Apache trout have been extirpated.
The relict populations have remained pure and are self-sustaining
without the need for restocking since their discovery (Leon 2022, pers.
comm.).
Following the initial introduction of 100-200 individuals, most of
the replicate populations did not require additional introduction of
individuals (USFWS 2022b, p. 58). However, periodic introductions of
additional individuals from the same donor streams have been made in
subsequent years in several populations to improve genetic diversity
within replicated populations and to reduce impacts to donor streams
from large, one-time transfers. Replicate populations were established
as early as 1967 and as late as 2008.
In order to ensure that genetically pure populations of Apache
trout are protected, conservation barriers that prohibit nonnative
trout species from accessing upstream portions of occupied Apache trout
habitat have been and will continue to be constructed and maintained
per the CMP. The prevents nonnative trout from hybridizing with,
competing with, and preying on Apache trout.
Delisting Criterion 3: Appropriate angling regulations are in place
to protect Apache trout populations while complying with Federal,
State, and Tribal regulatory processes. This criterion has been met.
Apache trout streams are protected with fishing closures when
populations are small and vulnerable, and with catch-and-release
regulations in larger populations where harvest could negatively impact
the population. AZGFD does provide put-and-take opportunities for
Apache trout in Silver Creek, East Fork Black River, and West Fork
Little Colorado River to generate public support for recovery of the
species, as does WMAT in the North Fork White River, lower East Fork
White River, Cibeque Creek, lower Paradise Creek, and lower Diamond
Creek. Apache trout fisheries are also established in some lakes (e.g.,
Big Bear, Hurricane, Christmas Tree, Earl Park) to afford the public
opportunities to harvest Apache trout, which also has the benefit of
raising public awareness for the species.
Delisting Criterion 4: Agreements are in place between the Service,
AZGFD, and WMAT to monitor, prevent, and control disease and/or
causative agents, parasites, and pathogens that may affect Apache
trout. This criterion has been met. By December 2021, the Service,
AZGFD, USFS, WMAT, and Trout Unlimited had all signed the cooperative
management plan (CMP) for Apache trout. The goal of the CMP is to
ensure the long-term persistence of the Apache trout by monitoring and
maintaining existing populations, establishing new populations,
restoring and maintaining existing habitats, and conducting disease,
parasite, and pathogen prevention and monitoring activities. Although
the CMP is a voluntary agreement among the cooperating agencies, it is
reasonable to conclude the plan will be implemented into the future for
multiple reasons. First, each of the cooperating agencies have
established a long record of engagement in conservation actions for the
Apache trout. Many of the management activities, such as the
construction of conservation barriers, have been ongoing since at least
the 1990s (USFWS 2022b, pp. 70-73). Second, implementation of the CMP
is already underway. Conservation barriers are being constructed and
maintained, invasive species are being removed, planning is underway
for restocking Apache trout as needed, and habitats are being repaired
and restored. Third, the conservation mission and authorities of these
agencies authorize this work even if the species is delisted. Fourth,
there is a practical reason to anticipate implementation of the CMP
into the future: the plan's actions are technically not complicated to
implement, and costs are relatively low. We also have confidence that
the actions called for in the CMP will be effective in the future
because they have already proven to be effective as evidenced by the
information collected from recent habitat actions and associated
monitoring (USFWS 2022b, entire). Lastly, if the CMP is not adhered to
by the cooperating agencies or an evaluation by the Service suggests
the habitat and population numbers are declining, the Service would
evaluate the need to again add the species to the List (i.e.,
``relist'' the species) under the Act. Taken together, it is therefore
reasonable to conclude that the CMP will be implemented as anticipated,
and that the long-term recovery of Apache trout will be maintained and
monitored adequately thus meeting the conditions of this criterion.
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
species. In 2019, jointly with the National Marine Fisheries Service,
the Service 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 the criteria for designating listed species'
critical habitat (84 FR 45020; August 27, 2019). On the same day the
Service also issued final regulations that, for species listed as
threatened species after September 26, 2019, eliminated the Service's
general protective regulations automatically applying to threatened
species the prohibitions that section 9 of the Act applies to
endangered species (84 FR 44753; August 27, 2019). 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;
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(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. The determination to delist a
species must be based on an analysis of the same five factors.
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 now and in the
foreseeable future.
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. The term
``foreseeable future'' extends only so far into the future as we can
reasonably determine that both the future threats and the species'
responses to those threats are likely. In other words, the foreseeable
future is the period of time in which we can make reliable predictions.
``Reliable'' does not mean ``certain''; it means sufficient to provide
a reasonable degree of confidence in the prediction. Thus, a prediction
is reliable if it is reasonable to depend on it when making decisions.
It is not always possible or necessary to define the foreseeable
future as a particular number of years. Analysis of the foreseeable
future uses the best scientific and commercial data available and
should consider the timeframes applicable to the relevant threats and
to the species' likely responses to those threats in view of its life-
history characteristics. Data that are typically relevant to assessing
the species' biological response include species-specific factors such
as lifespan, reproductive rates or productivity, certain behaviors, and
other demographic factors.
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 delisting. 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 viability of the Apache trout, 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 species' ecological requirements for survival and
reproduction at the individual, population, and species levels, and
described the beneficial and risk factors influencing the species'
viability.
The SSA process can be categorized into three sequential stages.
During the first stage, we evaluated the species' life-history needs.
The next stage involved an assessment of the historical and current
condition of the species' demographics and habitat characteristics,
including an explanation of how the species arrived at its current
condition. The final stage of the SSA involved making predictions about
the species' 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
a species to sustain populations in the wild over time. We use this
information 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-R2-
ES-2022-0115 on https://www.regulations.gov and at https://ecos.fws.gov/ecp/species/3532.
Summary of Biological Status and Threats
We reviewed the biological condition of the species and its
resources, and the threats that influence the species' current and
future condition, in order to assess the species' overall viability and
the risks to that viability.
The primary threats affecting the Apache trout are the invasion of
Apache trout habitat by nonnative trout species and the effects of
climate change, which are projected to result in more wildfire and
debris runoff in streams. Introgression of nonnative trout species into
Apache trout habitat has resulted in hybridization of certain
populations. Additionally, nonnative trout species also compete with
the Apache trout and certain species have been known to prey on the
Apache trout. In addition to invasion by nonnative trout, wildfires in
the region can result in ash and debris flow, creating unsuitable
conditions for the Apache trout and possibly resulting in fatalities
and extirpation of populations. To address these major threats,
management actions, including construction of conservation barriers, as
well as restocking and restoring habitats, have been implemented.
Nonnative Species
Nonnative species, especially nonnative salmonids, remain one of
the
[[Page 54554]]
largest threats to the Apache trout (Rinne 1996, p. 152). Over 61
million nonnative sport fishes have been stocked into lakes in the
Little Colorado and Black River drainages since the 1930s (Rinne and
Janisch 1995, p. 398). Over 8 million nonnative sport fishes were
introduced directly into the Little Colorado and Black rivers and their
tributaries since the 1930s, and many of these were nonnative salmonids
(Rinne and Janisch 1995, p. 398). Recent stocking practices have been
altered to reduce interactions with, and risks to, native species, such
as using triploid (sterile) rainbow trout for stocking into open water
systems (EcoPlan Associates 2011, p. 21). However, threats remain due
to acclimated nonnative populations from historical stockings.
As discussed below, hybridization with rainbow trout and cutthroat
trout can lead to functional extirpation of populations. Competition
with and predation by brown trout and brook trout are also of high
concern. While no published studies have documented competition and
predation impacts on Apache trout by nonnative salmonids such as brown
trout and brook trout, it is generally accepted that the negative
interaction has led to reduction or extirpation of some populations
(Rinne 1996, p. 152). Appendix C of the SSA report analyzes the
negative effect of nonnative trout presence on occupancy of juvenile
(less than 125 mm total length (TL)) Apache trout at the site scale
(approximately 100 m) in fish surveys (USFWS 2022b, p. 134-137).
Genetic Factors (Population)
Discussed below are the three genetic factors that pose a risk to
the viability of Apache trout populations: hybridization, inbreeding,
and low genetic variability.
Hybridization
Hybridization can introduce traits that are maladaptive, disrupt
adaptive gene complexes, or result in outbreeding depression (Hedrick
2000, entire). Hybridization can also lead to the loss of species-
specific alleles, and hybridization with Pacific trout species has long
been recognized as a threat to the viability of native trout species
(or subspecies) (Behnke 1992, p. 54). This has resulted in arguments
that only genetically pure populations should be considered a part of
the species or subspecies (Allendorf et al. 2004, p. 1212).
A long history of nonnative trout stocking in Arizona has led to
hybridization between Apache trout and rainbow trout, even to the
extent of genetic extirpation, and it is one of the main reasons for
the historical decline of Apache trout (Rinne and Minckley 1985, pp.
285, 288-291; Carmichael et al. 1993, pp. 122, 128; Rinne 1996, pp.
150-152). The major threat of hybridization is why the 2009 revised
recovery plan lists as an objective the establishment and/or
maintenance of 30 self-sustaining, discrete populations of genetically
pure Apache trout within its historical range (USFWS 2009, pp. vi, vii,
5, 22). That same objective has largely been in place since the first
recovery plan was developed for the species in 1979 (USFWS 1979, p.
15). A comprehensive assessment of the genetic purity of naturally
reproducing Apache trout populations showed only 11 of 31 streams are
deemed to be generically pure (Carmichael et al. 1993, p. 128). At the
time the 2009 revised recovery plan was completed, 28 populations of
genetically pure Apache trout were extant (USFWS 2009, p. 2).
Currently, the Apache trout consists of 29 genetically pure populations
and one population suspected to be genetically pure.
Inbreeding and Low Genetic Diversity
As discussed earlier, small populations are more likely to exhibit
inbreeding and low genetic diversity. Inbreeding often results in
inbreeding depression and expression of recessive and deleterious
alleles (Wang et al. 2002, p. 308). Cutthroat trout are an example of
inland trout in North America where inbreeding has been documented for
some small, isolated populations (Metcalf et al. 2008, p. 152; Carim et
al. 2016, pp. 1368-1372). Low genetic diversity limits the ability of
populations to adapt to changing and novel environments (Allendorf and
Ryman 2002, pp. 62-63).
The only study of genetic diversity in Apache trout showed strong
distinction among three genetic lineages (Soldier, Ord, and East Fork
White River lineages) represented by the nine populations studied, but
genetic diversity was low within populations (Wares et al. 2004, pp.
1896-1897). Low genetic diversity within populations suggests that they
were founded with a small number of individuals. Replicate populations
of Apache trout have often been established with only a few hundred
individuals, with an unknown subset successfully reproducing. Although
no studies have evaluated inbreeding in Apache trout populations, or
how genetic management (e.g., genetic rescue) may benefit Apache trout
populations, these topics remain of management interest given the
relatively small size of many extant populations (Wang et al. 2002, pp.
308, 313-315; Whiteley et al. 2015, pp. 42-48; Robinson et al. 2017,
pp. 4418-4419, 4430).
Climate Change, Wildfire, Stream Conditions
The climate has changed when compared to historical records, and it
is projected to continue to change due to increases in atmospheric
carbon dioxide and other greenhouse gasses (USGCRP 2017, pp. 10-11).
The American Southwest has the hottest and driest climate in the United
States. The U.S. Fourth National Climate Assessment suggests that
warming temperatures will lead to decreasing snowpack, increasing
frequency and severity of droughts, and increasing frequency and
severity of wildfires, and these in turn will result in warmer water
temperatures, reduced streamflows (especially baseflows), and increased
risk of fire-related impacts to aquatic ecosystems (Gonzales et al.
2018, pp. 1133-1136; Overpeck and Bonar 2021, p. 139). In fact, the
current drought in the western United States is one of the worst in the
last 1,200 years and is exacerbated by climate warming (Williams et al.
2020, p. 317). Climate warming will make droughts longer, more severe,
and more widespread in the future.
An eight-fold increase in the amount of land burned at high
severity during recent wildfires, including in the southwestern United
States, has been observed and it is likely that warmer and drier fire
seasons in the future will continue to contribute to high-severity
wildfires where fuels remain abundant (Parks and Abatzoglou 2021, p.
6). Wildfires have increased in frequency and severity in Arizona and
New Mexico primarily due to changes in climate but also because of
increased fuel loads (Mueller et al. 2020, p. 1; Parks and Abatzoglou
2021, pp. 5-7), including within the historical range of the Apache
trout (Dauwalter et al. 2017b, entire). Larger, more frequent, and more
severe wildfires accompanying a changing climate together may drive
conversions in vegetation type from forest to shrub or grassland
because of higher tree mortality, limited seed dispersal in larger burn
patches, soil damage that reduces seedling establishment, and a
changing climate that reduces seedling survival--all of which combine
to inhibit forest regeneration (Keeley et al. 2019, p. 775; Coop et al.
2020, p. 670). Wildfires can result in ash flows that create unsuitable
water quality conditions for salmonids, and high-intensity fires in
steep watersheds are likely to result in channel-reorganizing debris
flows (Gresswell 1999, pp. 210-
[[Page 54555]]
211; Cannon et al. 2010, p. 128). Approximately 30 percent of forests
in the Southwest are projected to have an elevated risk of conversion
to shrubland and grassland because of increased fire severity due to
climate change (Parks et al. 2019, p. 9). Conifer reduction in the
White Mountains could reduce stream shading important for maintaining
suitable stream temperatures for Apache trout (Baker and Bonar 2019,
pp. 862-864).
In the absence of existing peer-reviewed science on the effects of
climate change on the Apache trout itself, we applied the vulnerability
assessment approach that was used to evaluate wildfire and temperature
warming vulnerability in Gila trout streams and applied it to Apache
trout populations (USFWS 2022b, pp. 121-130). The analysis suggests
that streams such as West Fork Little Colorado River have a high risk
of crown fire (wildfire spreading at the canopy level) and subsequent
debris flows. Other streams in the Wallow Fire perimeter have a lower
risk of future wildfires due to reduced fuel loads. To evaluate stream
temperature risk due to climate warming, we first evaluated Apache
trout occupancy across all habitat patches and found that 95% of all
occupied patches occurred in reaches at or below 16.5 [deg]C (61.7
[deg]F) mean July water temperatures. Then all streams were modeled to
contain reaches where mean July water temperatures were less than or
equal to 16.5 [deg]C (61.7 [deg]F), a conservative temperature
threshold, based on temperature projections for the 2080s from an
ensemble global climate model for the A1B emissions scenario (i.e.,
middle-of-the-road scenario). Big Bonito Creek, Fish Creek, and Boggy/
Lofer Creeks contained the largest amount of habitat with mean July
temperatures less than 16.5 [deg]C (61.7 [deg]F) in the 2080s. The East
Fork Little Colorado River, Snake Creek, Rock Creek, Rudd Creek, and
South Fork Little Colorado River had the lowest percent of habitat with
mean July temperatures less than or equal to 16.5 [deg]C (61.7 [deg]F)
in the 2080s, highlighting their vulnerability to future climates.
Cumulative Impacts
We note that, by using the SSA framework to guide our analysis of
the scientific information documented in the SSA report, we have not
only analyzed individual effects on the species, but we have also
analyzed their potential cumulative effects. We incorporate the
cumulative effects into our SSA analysis when we characterize the
current and future conditions of the species. To assess the current and
future conditions of the species, we undertake an iterative analysis
that encompasses and incorporates the threats individually and then
accumulates and evaluates the effects of all the factors that may be
influencing the species, 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 species, our assessment integrates the cumulative effects of the
factors and replaces a standalone cumulative effects analysis.
Conservation Management and Actions
Several conservation actions are routinely undertaken to protect,
restore, and re-establish Apache trout populations across the species'
historical range and, in one case, outside of the historical range.
Discussed below are the major efforts which include removal of
nonnative trout species, reintroduction of Apache trout, habitat
maintenance and restoration, hatchery propagation, and angling
regulations. These activities are managed under the CMP. The CMP will
remain in force until terminated by mutual agreement. Any involved
party may withdraw from this plan on 30 days' written notice to the
other signatories. Amendments to the CMP may be proposed by any
involved party and will become effective upon written approval by all
partners.
Nonnative Trout Removal
Removal of nonnative salmonids often occurs after conservation
barriers are constructed and before Apache trout are reintroduced, or
removals are done when nonnative salmonids have invaded an extant
Apache trout population. As noted above, conservation barriers are
artificial barriers built to separate upstream populations of Apache
trout from downstream populations where other trout species and hybrids
are found. These downstream populations are managed to provide
sportfishing opportunities. Removal is commonly done using piscicides
(chemicals that are poisonous to fish) or electrofishing. A few studies
have documented the higher effectiveness of piscicides on removing
nonnative salmonids from Apache trout streams, although more than one
treatment may be required (Rinne et al. 1981, p. 78; Kitcheyan 1999,
pp. 16-17).
Electrofishing (often referred to as mechanical removal) is also
used to remove nonnative fishes where piscicides have not been approved
for use, or where populations of Apache trout are sympatric with
nonnative trout, and it is not desirable to eliminate Apache trout
simultaneously with nonnative trout. For example, electrofishing was
used from 2018 to 2021, to remove over 14,670 brook trout and 3,932
brown trout from nine Apache trout streams, with successful eradication
suspected in some streams that will be later confirmed with future
electrofishing or environmental DNA (eDNA) surveys (Manuell and Graves
2022, p. 8). Piscicides are typically more effective at ensuring all
fish are removed, which is important because nonnative populations can
become reestablished if only a few individuals survive (Thompson and
Rahel 1996, pp. 336-338; Finlayson et al. 2005, p. 13; Meyer et al.
2006, p. 858). Electrofishing removal is most effective in small stream
systems with simple habitat (Meyer et al. 2006, p. 858). Environmental
DNA surveys are conducted to confirm presence or absence of target
organisms; this technique is often used in native trout conservation
projects to help locate any remaining nonnative fish and target them
for removal using either electrofishing or secondary applications of
piscicides (Carim et al. 2020, pp. 488-490).
Reintroduction
Apache trout are typically reintroduced after the habitat is
protected by a conservation barrier and nonnative salmonids have been
removed. Apache trout populations are usually established using fish
from another population, although hatchery stocks have been used to
establish populations as well. The donor stream is selected, in part,
based on the number of fish in that population so that removing some
does not jeopardize donor population viability, but donor stream
selection is also based on the need to replicate relict populations to
enhance redundancy of those lineages. Planning efforts are underway to
establish additional populations where feasible, for example in Fish
Creek, Hayground Creek, Home Creek, and the lower West Fork-Black
River. Historically, 100-200 fish have been used to establish
populations, but there is evidence that this low number of founding
individuals has resulted in the low genetic diversity observed in some
populations (Wares et al. 2004, pp. 1896-1897). Future populations will
be established using larger total numbers over several years to
maximize genetic diversity while minimizing impacts to donor
populations (USFWS et al. 2021, p. 13).
[[Page 54556]]
Habitat Management and Restoration
Past habitat surveys and anecdotal observations have identified
stream segments in poor condition and in need of protection and
restoration (Carmichael et al. 1995, p. 116; Robinson et al. 2004, pp.
1-3, 14-17). The subbasins where Apache trout are found are managed by
multiple agencies at the Federal, State, and Tribal level. The
management of the individual subbasins are as follows: Black River
(WMAT, USFS/AZGFD), Bonito Creek (WMAT), East Fork White River (WMAT),
North Fork White River (WMAT), Diamond Creek (WMAT), Little Colorado
River (USFS/AZGFD), and Colorado River (AZGFD). Of the 29 known
genetically pure populations and 1 suspected pure population, 16 relict
and 6 replicated populations occur only on WMAT lands, 1 relict and 1
replicated population occur on both WMAT and USFS/AZGFD managed lands
(Soldier Creek and upper West Fork Black River, respectively), 5
replicated populations occur only on USFS/AZGFD managed lands, and 1
replicated population occurs on both San Carlos Apache Tribe and USFS/
AZGFD managed lands (Bear Wallow Creek).
The habitat of Apache trout is managed to ameliorate land-use
impacts through environmental review of proposed projects. For example,
WMAT has land management plans that help protect Apache trout
populations and has implemented habitat restoration projects. Projects
occurring on or adjacent to Apache trout habitat include alteration of
logging practices, road closure and removal, and ungulate exclusion
through fencing or retiring allotments, and all have been reviewed for
potential impacts to Apache trout habitat on the ASNF and Fort Apache
Indian Reservation (Robinson et al. 2004, entire 1; USFWS 2009, p. 23).
While these actions have reduced land-use impacts, further emphasis
should be given to restoration of riparian and aquatic habitats (ASNF
2018, pp. 19-20). The Southwest Region of the U.S. Forest Service has
the Riparian and Aquatic Ecosystem Strategy (Strategy; USFS 2019,
entire), and restoration of aquatic habitat is identified through site-
specific land management actions, such as the currently ongoing Black
River Restoration Project (BRRP). Working with partners on such actions
is outlined in the Strategy (USFS 2019, pp. 17-18).
Hatcheries
Hatcheries have been used for Apache trout conservation and to
establish sportfishing opportunities in lakes and streams. Apache trout
from Williams Creek National Fish Hatchery have been used to establish
populations including those in the West Fork Little Colorado and West
Fork Black rivers, but they have been most often used to provide
sportfishing opportunities in lakes and streams on the Fort Apache
Indian Reservation. Progeny from the Apache trout broodstock at
Williams Creek National Fish Hatchery are also transferred annually, at
the direction of WMAT, to be reared at Arizona's Silver Creek and Tonto
Creek hatcheries and stocked to support sportfishing on State-managed
lands. This broodstock is expected to be used to establish additional
recovery populations in the future due to improvements in genetic
fitness and representation following implementation of a genetics
management plan.
Angling and Harvest Regulations
Apache trout streams are largely protected with fishing closures
when populations are small and vulnerable, or by catch-and-release
regulations in larger populations where harvest could negatively impact
the population. WMAT does not allow any fishing to occur in areas
occupied by Apache trout recovery populations. However, both WMAT and
AZGFD provide put-and-take opportunities for Apache trout in multiple
lakes and streams to afford the public opportunities to harvest Apache
trout and generate public awareness and support for recovery of the
species.
Emergency Contingency Plan
Wildfire, drought, nonnative trout invasions (e.g., barrier
failure), and disease can threaten the viability and genetic integrity
of Apache trout populations. We and our partners will track these
threats during the monitoring described in the CMP or through other
monitoring and reporting systems. If needed, we and our partners in the
CMP will transport individuals to other streams or hatcheries with
suitable isolation facilities until they can be repatriated into their
original or an alternate site (USFWS et al. 2021, p. 13).
Current Condition
Resiliency--Demographic and Habitat Factors
Resiliency references the ability of a species or population to
bounce back from disturbances or catastrophic events, and is often
associated with population size, population growth rate, and habitat
quantity (patch size) and quality (USFWS 2016, p. 6).
Three demographic and six habitat factors were used to describe the
current condition (status) and overall resiliency of Apache trout
populations. These factors are commonly used to describe the health and
integrity of native trout populations in the western United States
(Williams et al. 2007, pp. 478-481; USFWS 2009, pp. 17-22; Dauwalter et
al. 2017a, pp. 1-2). The three demographic factors are genetic purity,
adult population size, and recruitment variability. The six habitat
factors are stream length occupied, July temperature, percent of
intermittency, habitat quality, nonnative trout presence, and barrier
effectiveness.
Hybridization can introduce traits that are maladaptive or result
in outbreeding depression. Thus, often only genetically pure
populations are considered to be part of a species for conservation
purposes. Apache trout populations were classified using the results of
the most recent genetic testing for the presence of nonnative trout
alleles (rainbow trout and cutthroat trout) when available (Carmichael
et al. 1993, p. 127; Carlson and Culver 2009, pp. 5-9; Weathers and
Mussmann 2020, pp. 4-7; Weathers and Mussmann 2021, pp. 4-7). Genetic
material (e.g., fin clips) is often collected during population
monitoring, or it is collected during surveys targeting fish for
genetic testing if there is evidence that barriers are compromised or
other evidence suggest that hybridizing species (rainbow trout and
cutthroat trout) or hybrid individuals may be present (e.g., from
visual assessment). In the absence of genetic testing, the presence of
hybridizing species, presence of hybrid phenotypes, or professional
judgment based on putative barrier effectiveness were used to classify
populations as being genetically pure or hybridized.
Adult population size is the estimated number of adult Apache trout
(greater than or equal to 130-mm TL) in a population in the most recent
year of population monitoring. Before 2016, estimates of streamwide
adult abundance were made from monitoring data collected under the
Basinwide Visual Estimation Technique (BVET) protocol (Dolloff et al.
1993, pp. v-17), and in a few cases, from information collected during
general aquatic wildlife surveys (e.g., Robinson et al. 2004, pp. 3-13)
or from electrofishing data (catch per single electrofishing pass) when
collecting tissues for genetic analysis (such as was used in Carlson
and Culver 2009). Since 2016, estimates of adult abundance have been
based on an
[[Page 54557]]
updated systematic sampling design (Dauwalter et al. 2017a, entire).
Recruitment variability seeks to quantify the number of size
classes present. The presence of individuals in more size (and
therefore age) classes is indicative of more stable recruitment from
year to year, which indicates that populations are more able to
withstand year-to-year environmental variability (stochasticity;
Maceina and Pereira 2007, pp. 121-123). Length frequency data from
monitoring surveys were used to determine the number of size classes
present. Before 2016, these data were collected under the BVET (Dolloff
et al. 1993, pp. v-17) protocol, during general aquatic wildlife
surveys (e.g., Robinson et al. 2004, pp. 3-13), or from electrofishing
data when collecting tissues for genetic analysis (such as was used in
Carlson and Culver 2009). Since 2016, these data have been based on the
updated systematic sampling design (Dauwalter et al. 2017a, entire).
The length of an occupied stream, often referred to as patch size,
was measured in kilometers using the National Hydrography Dataset
(1:24,000 scale), and upstream and downstream extents were typically
defined by experts as the extent of occupancy from fish survey data,
suitable habitat, or barriers to fish passage (conservation barriers).
Extent of occupied habitat has been shown to be positively associated
with the probability of population persistence (e.g., viability,
extinction probability) for western native trout (Harig et al. 2000,
pp. 997-1000; Hilderbrand and Kershner 2000, pp. 515-518; Finlayson et
al. 2005, p. 13), and it has been used as an indicator of persistence
in indices of population health and as an indicator of translocation
success (Harig and Fausch 2002, pp. 546-548; Williams et al. 2007, pp.
479-480; Cook et al. 2010, pp. 1505-1508).
We selected July temperature as a measurement of habitat quality
because the Apache trout, like other salmonids, is a cold-water
stenotherm (a species that can survive only within a narrow range of
temperature). Under Climate Change, Wildfire, Stream Conditions, above,
we highlight the thermal tolerance and habitat suitability values
derived from several laboratory and field studies of Apache trout. The
maximum mean July temperature in habitat extent occupied by each Apache
trout population is based on modeled average July temperatures
predicted for each 1-km stream segment in Arizona from the NorWeST
dataset (Isaak et al. 2017, pp. 7-13). The NorWeST dataset predicts
mean August temperatures (average of mean daily temperatures for the
month of August) for each 1-km stream segment in the National
Hydrography Dataset (1:100,000 scale). These predictions were adjusted
based on an empirical relationship between mean August and mean July
(monthly mean of mean daily temperatures) temperatures in Apache trout
streams from data collected by USFS on ASNF.
Intermittency percentage is the percent of occupied habitat extent
estimated to become intermittent during severe drought years. The
percent of stream length occupied that becomes intermittent (dry)
during severe drought years due to low natural flows, decreasing flow
trends in recent years, anthropogenic impacts to flow, or other
factors. The percentage was based on professional judgment and
knowledge of the habitat. The southwestern United States is a naturally
warm and dry environment with reduced surface water resources that may
subside due to low annual precipitation (snowpack and rainfall) and
interactions with local geology (Long et al. 2006, pp. 90-94). The
region is currently in a megadrought that has large consequences for
streamflows (Williams et al. 2020, p. 314), and other researchers
highlighted the time period from 2000 to 2003 as a severe drought
period (Hoerling and Eischeid 2007, p. 2).
Habitat quality is the condition of riparian and instream habitat
throughout the occupied habitat extent. Stream habitat quality was
classified based on professional judgment at the whole stream scale or
by segment and then computed as a weighted average (weighted by
length).
The presence of rainbow trout, brown trout, brook trout, or
cutthroat trout within the habitat accessible to the Apache trout
population (or defined habitat extent) is either confirmed or not
present. Rainbow trout and cutthroat trout have been documented to
hybridize with Apache trout (Carmichael et al. 1993, p. 128), and brown
trout and brook trout compete with and prey on Apache trout, thus
reducing the carrying capacity of habitat to support Apache trout
(Carmichael et al. 1995, p. 114). Presence of each species is
attributed based on survey data, angler reports, anecdotal information,
and, in some cases, barrier effectiveness and proximity of nonnative
species and likelihood of invasion upstream of ineffective barriers.
Barriers were classified as functional or nonfunctional, and
functionality was classified as known or suspected. Functionality was
classified based on documented presence of nonnative trout above a
barrier, documented movement of marked fish from below to above a
barrier, known streamflow paths around or through barriers, poor
structural integrity, or other factors influencing perceived
functionality based on professional judgment. On some streams, more
than one conservation barrier has been constructed to provide
functional redundancy and security due to possible failure, as well as
to allow management flexibility for controlling nonnative trout
invasions or conducting nonnative trout removals (mechanical or
chemical).
Resiliency
Demographic and habitat factor data show that relict and hybridized
Apache trout populations occur in two major river basins (the Black
River and White River basins), replicate populations occur in all major
basins (including one replicate population outside the species'
historical range in the Colorado River), and unoccupied recovery
streams occur in the Little Colorado River and Black River basins.
Relict populations occur in five of six subbasins to which they are
native. Hybridized populations occur in the Black River and Diamond
Creek subbasins. As mentioned previously, of the 38 extant populations
of Apache trout, 29 populations of Apache trout are known to be pure,
with one population suspected to be genetically pure (81.1 percent).
One of eight (12.5 percent) populations has been confirmed as
hybridized through genetic testing, whereas seven have been assumed to
be hybridized because of known barrier failures and invasion of rainbow
trout.
A summary of demographic factors showed a majority of Apache trout
populations to have adult (greater than 130-mm TL) population sizes
that are fewer than 500 individuals (see table 11 in USFWS 2022b, p.
86); one population, East Fork White River, was estimated to have more
than 2,200 adults (see table 11 in USFWS 2022b, p. 86). Despite low
abundances, most populations showed consistent recruitment, with four
or five size classes (and presumably year classes) present, which
suggests they are stable and self-sustaining populations (see figure
18C in USFWS 2022b, p. 83).
Habitat factors for Apache trout populations showed a wide range of
current conditions. The extent of stream occupied by Apache trout
populations ranged from 0.4 (0.25 mi) to 30.1 km (18.7 mi); most were
less than 14 km (8.7 mi). Maximum mean July temperatures in occupied
habitat were less than or equal to 15.5 [deg]C for relict and replicate
populations, whereas
[[Page 54558]]
unoccupied streams and hybrid populations had warmer maximum mean July
temperatures up to 17.5 [deg]C. Most populations or unoccupied streams
exhibited little intermittency during severe drought, but two
hybridized populations and one unoccupied stream were estimated to be
more than 50 percent intermittent (up to 95 percent). Unoccupied
streams and streams occupied by hybrid populations had the lowest
habitat quality (in part due to 2011 Wallow Fire), while a majority of
relict and replicate populations inhabited high-quality habitat.
Nineteen Apache trout populations were sympatric with brown trout, 7
with rainbow trout, and 2 with brook trout. Thirty-six populations or
unoccupied recovery streams currently have conservation barriers to
isolate them from nonnative fishes downstream, but only 31 populations
are protected by barriers that are known or suspected to be functional;
10 populations have a second barrier downstream for added protection
across all population types (relict, replicate, hybrid, unoccupied).
Overall, the current condition of the 38 Apache trout populations
(excluding the 6 unoccupied recovery streams) rated an average of 2.60
(B- average) on a 4.0 grading scale (USFWS 2022b, p. 7, 88). The 30
genetically pure populations that would count towards recovery averaged
2.89 (B average). Based on the demographic and habitat factor grade
point equivalents for each population, Apache trout populations were
more often limited by demographic factors than habitat factors. Adult
(greater than 130-mm TL) population size was most frequently the
limiting demographic factor, as most populations were fewer than 500
adults and received lower grades. Unoccupied streams (e.g., Home Creek)
had demographic GPAs (grade point averages) equaling 0.0. East Fork
White River had the highest demographic GPA (4.00). Likewise, presence
of nonnative trout was frequently a limiting habitat factor. Centerfire
and Stinky creeks on the Apache-Sitgreaves National Forests (ASNF) had
the lowest habitat factor (GPA of 1.33); Deep Creek (WMAT) had the
highest habitat factor (GPA of 3.50).
Redundancy and Representation
Representation and redundancy for Apache trout were evaluated by
quantifying the presence of relict populations, and their replication
on the landscape, as putative genetic lineages at the subbasin level.
Representation was based on presence of genetically pure relict
populations from each subbasin. Redundancy was measured as the
replication of relict lineages into new streams by subbasin.
Replication of relict populations, and thus redundancy of purported
relict subbasin lineages, was measured both within and outside of the
native subbasin for each subbasin genetic lineage. The number of
populations that meet certain persistence, abundance, and recruitment
criteria can also be used to quantify population redundancy by subbasin
or a larger basin unit (e.g., geographic management unit). Tracking the
representation and redundancy of relict populations by subbasin, as
subbasin lineages, is a surrogate for the assumed unique genetic
diversity, and presumed unique adaptation potential, that is often
found to be structured around the hierarchical nature of drainage
basins (Vrijenhoek et al. 1985, pp. 400-402; Wares et al. 2004, pp.
1890-1891, 1897). While such genetic structuring is evident in Apache
trout for the 9 populations (and three genetic lineages) that have been
studied (Wares et al. 2004, pp. 1895-1896), no comprehensive rangewide
study of genetic diversity has been conducted across all genetically
pure populations. Accounting for relict Apache trout populations in
this way presumably reflects the representation and redundancy of
genetic diversity, and thus adaptive potential, of the species in each
subbasin in which it is native.
When quantified in this way, extant relict populations exist in 5
of 6 subbasins within the historical range of the Apache trout; only
the Little Colorado River subbasin is no longer represented within an
extant relict lineage. The East Fork White River subbasin has the
highest level of redundancy and representation; it contains six relict
populations still extant within the subbasin and four replicated
populations in other subbasins that were founded with individuals from
relict populations native to the East Fork White River subbasin. Of the
subbasins containing relict populations, the Black River and Diamond
Creek subbasins contain the lowest level of redundancy and
representation, with three populations each occurring on the landscape
(Black River: one relict and two replicates; Diamond Creek: two relicts
and one replicate).
Future Condition
The primary threats affecting Apache trout viability include
invasion by nonnative trout and climate change, which encompasses
warmer stream temperatures, more frequent and severe droughts,
increased wildfire frequency and post-fire debris flow, reduced
snowpack and increased rain on snow events, and more intense summer
monsoon precipitation. A 30-year future (which equates to approximately
six generations of Apache trout) was chosen for our future condition
projections because within this timeframe it is likely that these
primary threats will continue to impact the species, and also because
it is biologically reasonable to assess the species' response to these
threats within this timeframe. Additionally, this timeframe allows us
to reasonably forecast upcoming management activities as they will be
implemented through the CMP.
The threats that can be actively managed through implementation of
the CMP include introduction of nonnative trout, and wildfire and post-
fire debris flow. Nonnative trout impact the Apache trout in multiple
ways including hybridization, predation, and competition. Wildfires
primarily produce debris flows that render habitat unsuitable for the
species. To mitigate these two threats, conservation actions that have
been and will continue to be undertaken are most important to the
future viability of the Apache trout. These actions include the
construction and maintenance of conservation barriers, removal (by
physical or chemical means) of nonnative trout species, restocking of
Apache trout via hatchery and/or existing relict populations,
restoration of Apache trout habitats and reduction of fuel loads to
reduce the risk of wildfires, and fish salvages following wildfires per
the CMP. Continued construction and maintenance of conservation
barriers will be needed to prevent hybridization of the Apache trout
with other trout species, as well as to prevent competition with and
predation by other fish species. Continued conservation actions,
implemented through the CMP as well as by other mechanisms, will
therefore play a critical role in determining the overall viability of
the Apache trout into the future.
Climate change threats that are more uncertain and difficult to
mitigate include warming stream temperatures, more frequent and severe
droughts, reduced snowpack with increased rain on snow events, and more
intense summer monsoon precipitation. The future scenarios that were
developed for Apache trout incorporate these factors in order to
evaluate how climate variability might influence future condition for
the species.
While the SSA report contains a total of five scenarios, in
determining the future condition and status of the species for this
rulemaking we
[[Page 54559]]
determined that only two of the five scenarios are plausible. Scenarios
1 and 2 in the SSA assumed that no multi-agency CMP would be in place
after the species is delisted; however, since the SSA report and the
scenarios were developed the CMP has been signed and is currently being
implemented, making these scenarios not plausible. Our assessment of
scenarios indicated that scenario 5 is also not plausible given the
constraints involved with securing funding and commitment from partners
for ``greatly increased'' management of the species to occur (USFWS
2022b, p. 121). Given these factors, we did not consider scenarios 1,
2, and 5 and relied on scenarios 3 and 4 to inform our status
determination.
As noted above, a 30-year timeframe was chosen because it
encompasses six generations of Apache trout and is, therefore, a
biologically reasonable timeframe for assessing the likelihood of
threats as well as the species' response to those threats.
Additionally, this timeframe allows us to reasonably forecast upcoming
management activities that will be implemented through the CMP. The two
scenarios used for our status determination in this proposed rule
reflect both exogenous factors such as watershed condition and climatic
changes, as well as management action feasibility and volume given
funding and other programmatic constraints (funding and other
resources) and policy. The scenarios incorporate a status quo level of
management through the CMP, as well as potentially increased levels of
management through future conservation actions that could take place
throughout the future. Each scenario was based on a 30-year timeframe
and each includes climate change impacts and other factors impacting
the Apache trout, implementation of the CMP, and scientific and
technological advancement. The two scenarios from the SSA report that
we evaluated are:
Scenario 3 (Sustained Management, i.e., status quo): Recovery and
conservation efforts continue at sustained levels, which during the
years 2000-2020 were proven to be beneficial to Apache trout recovery.
This level of management will be maintained into the future as
prescribed by and implemented through the CMP. Thus, actions continue
and are effective at reducing some threats. This includes legally
required actions and those voluntarily agreed to in the CMP. Barrier
construction, population expansion, and nonnative trout removals occur
at levels required to meet recovery criteria (30 pure populations, or
similar) and are maintained thereafter. USFWS assistance to the White
Mountain Apache Tribe continues. Some funding sources disappear (e.g.,
National Fish and Wildlife Foundation Apache Trout Keystone
Initiative), but other funding sources emerge (e.g., National Fish
Habitat Act; Recovering America's Wildlife Act). This scenario
represented the status quo scenario with approximately the same level
of resources and management action as a 2000-2020 baseline.
Barrier installation and maintenance continues at 2000-
2020 levels. The number of viable Apache Trout populations and
metapopulations increases to meeting recovery goals and is maintained
after delisting.
Effectiveness of land management policies for stream
ecosystem and threatened species is initially maintained through de-
listing due to the CMP agreement in place. Across the Apache Trout
range, watershed functional conditions are maintained or improved,
riparian and instream habitat are maintained or improved in quality,
and stream temperatures are maintained or improved to support Apache
Trout due to protections during land management planning and
implementation.
Because of climate change, stream temperatures become
warmer, droughts continue to become more frequent and severe, risk of
wildfire and post-fire debris flow increases, snowpack decreases but
increased rain on snow events occur, and summer monsoon rains become
more intense.
Scenario 4 (Increased Management): Recovery and conservation
efforts continue but at levels increased slightly from 2000-2020
baseline levels that are beneficial to the species. Management actions
continue and some become effective at reducing some threats. After
barrier construction, population expansion, and nonnative trout
removals initially occur at levels required to meet recovery criteria
(30 pure populations, or similar) and Apache trout are delisted, the
level of actions is maintained due to the CMP in place, but also
increases due to emergence of new research and technology. USFWS
assistance to the White Mountain Apache Tribe continues. Legislation
emerges resulting in new funding sources for fish habitat projects
(e.g., National Fish Habitat Act; Recovering America's Wildlife Act),
and there is broad implementation of the Four Forest Restoration
Initiative, Black River Restoration Environmental Assessment (EA), and
FAIR Forest Management Plan (fuels management) that are beneficial to
watershed functional conditions and reduced wildfire risk.
Barrier installation and maintenance increases slightly
from 2000-2020 levels due to new technology that increases
effectiveness and reduces cost and maintenance. The number of viable
Apache trout populations increases, and one large metapopulation is
realized (e.g., WFBR), to meet and exceed recovery goals.
Effectiveness of land management policies for stream
ecosystem and threatened species is initially maintained through de-
listing due to the CMP in place. Across the Apache trout range,
watershed functional conditions are improved, riparian and instream
habitat are improved in quality, and stream temperatures are improved
(riparian restoration and recovery) to support Apache Trout due to
protections during land management planning and implementation.
Because of climate change, stream temperatures become
warmer, droughts continue to become more frequent and severe, risk of
wildfire and post-fire debris flow increases, snowpack decreases but
more rain on snow events occur, and summer monsoon rains become more
intense.
For each scenario provided in the SSA report, Apache trout core
team members indicated in an online survey the overall impact of each
scenario on populations across the species' range, or subsets of the
range with which they are familiar, using their best professional
judgment. Each core team expert responded to survey questions in terms
of what the condition--described as a GPA--of each Apache trout
population (or currently unoccupied stream) would be, based on the
grading scale used to describe current conditions above, under each of
the five future condition scenarios after a 30-year timeframe. GPAs
were summarized across populations to assess the influence of each
scenario on the rangewide status of Apache trout.
When survey responses of future condition were summarized
(averaged) across populations for scenarios 3 and 4 to infer a future
rangewide condition of the Apache trout under each scenario, the future
condition of the species under scenario 4 (increased management) was
expected to improve compared to scenario 3 (sustained management),
similar to that of individual populations.
Under scenario 3, which maintains the same level of conservation
management and actions as are currently being implemented through the
CMP, the condition of the species
[[Page 54560]]
was estimated at a GPA score of 2.53. This average score, however,
includes variation in populations. Under scenario 3, we project the
future condition of the majority of the relict populations would
modestly decline, resulting in slightly lower resiliency. These
declines are attributed to potential impacts from climate change and
its effect on forest fires that are not expected to be offset by other
management actions (e.g., nonnative trout eradication) which are
generally not currently needed in relict populations. On the other
hand, we project that some replicate populations would have slightly
better condition in the future compared to current conditions due to
completion of ongoing nonnative trout eradication efforts (e.g., West
Fork Black River [lower]) and planned replacement of nonfunctional
conservation barriers (e.g., West Fork Little Colorado River). Overall,
relative to current condition, the species' overall resiliency under
scenario 3 may modestly decline. Therefore, even though redundancy
would remain the same, representation may be slightly reduced due to
the projected decline of the Apache trout relict populations under
scenario 3.
Under scenario 4, which evaluates an increased level of
conservation management versus what is currently being implemented
through the CMP, the future condition of the Apache trout would be
essentially unchanged with a GPA score of 2.86. This represents a
nominal decrease when compared to the current condition GPA score of
2.89. Under scenario 4, we project slight improvement in future
conditions across some populations with other populations remaining
essentially unchanged or experiencing slight declines.
Some natural processes (e.g., purging of nonnative alleles) and
planned management actions not represented in scenarios 3 and 4 (e.g.,
new population establishment, metapopulation creation) are expected to
occur that will further improve specific and range-wide GPA scores.
Further, average grant funding to support field crews and conservation
projects obtained during 2020-2022 also far exceeds the average annual
funding obtained for similar work during the 2000-2020 baseline period.
Thus, future condition scores for scenarios 3 and 4 likely
underestimate actual future conditions for the species as additional
populations are created and maintained, nonnative trout populations are
eradicated, and populations with low levels of introgression purge
nonnative alleles over time.
Under both scenarios, the CMP plays an important role in
determining the species' future condition for threats that can be
managed. The CMP was drafted and signed to ensure that current
conservation efforts will continue in perpetuity. The signing of the
CMP has a demonstrable effect on the species' overall status with
current management level resulting in only a slight and modest decline
under scenario 3 (the status quo scenario). Scenario 4, in which
funding for conservation efforts would increase, results in maintaining
the species' overall future condition. Overall, the result of our
future scenarios analysis demonstrates the importance of continued
implementation of the CMP to ensure both the maintenance of current
populations and habitat, the restoration of degraded habitat, and the
establishment of new populations.
For climate-related threats to Apache trout that are not able to be
actively managed, we relied on a model developed to inform the
magnitude of effects that these factors might have through the
foreseeable future. For increased stream temperatures, our model
suggested that most streams currently occupied by Apache trout, or
unoccupied but designated as recovery streams, are not temperature
limited, and that suitability improved when 2080s projections of
temperature alone were considered because some headwater reaches
appeared to be currently too cold for occupancy. Most habitat patches
were not limited by warm stream temperatures because the habitat
designated for species recovery is upstream of protective fish passage
barriers (Avenetti et al. 2006, p. 213; USFWS 2009, p. 19; USFWS 2022b,
pp. 118-127) that are far enough upstream to not be temperature
limiting now or into the 2080s. In fact, the effect of temperature on
juvenile Apache trout occupancy suggested that streams can be too cold,
and model projections of stream temperature in the 2080s increased the
amount of suitable habitat in some streams because of the unimodal
response to temperature. This suggests cold temperatures can be
limiting Apache trout populations in some streams, and any warming may
benefit them in headwater reaches--at least up until the 2080s.
It was only when future changes in precipitation were considered in
tandem with stream temperature that habitat suitability decreased into
the 2080s. Many habitat patches that are currently occupied by the
species are projected to remain suitable into the 2080s, which suggests
their resiliency is only limited by the size of the patch they
currently occupy (Peterson et al. 2014, pp. 564-268; Isaak et al. 2015,
pp. 2548-2551; USFWS 2022b, pp. 135-140). However, when projections of
reduced precipitation were also considered, habitat suitability
decreased in Apache trout streams. This is not surprising given that
stream intermittency and drought have impacted some populations in the
past (Robinson et al. 2004, pp. 15-17; Williams et al. 2020, entire),
and less precipitation, and thus streamflow, would exacerbate these
impacts, especially since the Southwest is anticipated to experience
novel and mega-drought conditions in future climates (Crausbay et al.
2020, pp.337-348; Williams et al. 2020, entire).
Precipitation in the White Mountains primarily falls as winter snow
and summer monsoon rain (Mock 1996, pp. 1113-1124). However, decreases
in precipitation due to climate change are expected to occur in winter
in the form of snow (Easterling et al. 2017, p.207), and decreases in
snowpack are likely to negatively impact stream baseflows and, thus,
summer temperatures. Hydrologic models linked to climate models show
future precipitation increasingly falling as rain, higher frequency of
rain-on-snow, and increased snowmelt rates, all of which lead to
increased overland runoff to streams and less infiltration to
groundwater. Less groundwater storage leads to less groundwater
discharge to streams in late summer and early autumn (Huntington and
Niswonger 2012, pp. 16-18). The summer monsoon season can add
precipitation, but at much warmer temperatures regardless of whether it
occurs as overland flow or through shallow groundwater discharge
pathways.
While snow melt can result in overland flow during spring runoff,
it also infiltrates into groundwater and does so at near freezing
temperatures (at or just above 0 [deg]C (32 [deg]F); Potter 1991, pp.
847, 850). Thus, any groundwater contributions to streams that
originate from snowmelt are likely to have a stronger cooling effect on
stream temperatures released over longer time periods than overland
flow from either snowmelt or monsoon rains. If snowpack is reduced in
the future it is likely that groundwater return flows may occur earlier
and be less overall, thus providing less of a cooling effect into late
summer, especially prior to monsoon rains (Overpeck and Bonar 2021, pp.
139-141).
Determination of Status
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
[[Page 54561]]
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 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
The Apache trout is a species endemic to multiple river basins in
eastern Arizona. Due to conservation efforts undertaken within these
past decades, the Apache trout now encompasses the 29 genetically pure
populations and one suspected genetically pure population across three
basins and six subbasins. While these populations will continue to be
impacted by potential invasion of nonnative trout and debris runoff
from wildfire and climate change, construction and maintenance of
conservation barriers and restocking efforts have contributed to
restoration of habitats and populations. Currently, these 30 Apache
trout populations are assessed to possess good conditions (2.89 on a
4.0 grading scale). Within these 30 populations, relict populations
have an average GPA of 2.93, and replicate populations have an average
GPA of 2.85. These results demonstrate that both types of populations
contain moderate to good condition with the relict populations rated
slightly better.
Apache trout representation is best demonstrated within the 17
relict populations across five subbasins. While further studies would
need to be conducted to ascertain the genetic uniqueness of each relict
population, these populations are not derived from known populations,
suggesting that some of these populations could represent unique
genetic lineages for the species. To further preserve the genetic
diversity of the species, the Service and our partners have established
replicate populations within and alongside other subbasins, resulting
in the total of 30 populations across six subbasins. As noted above in
our resiliency discussion, through continuous monitoring, restoration
of habitat, and, if needed, restocking, these populations are rated as
being in fair or good condition. The genetic uniqueness of these
populations helps maintain the diverse gene pool of the species, giving
the species greater adaptive capacity to respond to environmental
changes.
The presence of multiple relict and replicate populations across
different subbasins demonstrates a high level of redundancy. Redundancy
is further enhanced through the creation of new replicate populations
from relict populations. These populations are created in adjacent
subbasins, providing greater protection for the species against
catastrophic events that may impact individual subbasins. Overall, the
presence of 30 populations across seven subbasins, with all being rated
as fair to good condition, provide the Apache trout with sufficient
redundancy to withstand catastrophic events that may impact the
species.
Lastly, as noted earlier, we have nearly met all criteria that the
recovery plan recommended for delisting. While we have not met the
criterion of 30 genetically pure populations within the historical
range of the species, 29 genetically pure populations exist within the
historical range, and one suspected genetically pure population exists
outside of the historical range. This represents a significant recovery
of the species and comes close to achieving all criteria spelled out in
the recovery plan. Recovery plan criteria are meant to function as
guidance for recovery rather than hard metrics that must be met.
Instead, we will use the best available information to determine the
status of the species. Overall, the Apache trout now consists of
multiple, sufficiently resilient populations across subbasins
encompassing a large percentage of the species' historical range.
Furthermore, while long-term threats such as nonnative trout species
will continue to persist, continued management of conservation barriers
will ensure that the threats do not negatively impact the species.
Accordingly, we conclude that the species is not currently in danger of
extinction, and thus does not meet the definition of an endangered
species, throughout its range.
In considering whether the species meets the definition of a
threatened species (likely to become an endangered species within the
foreseeable future) throughout its range, we identified the foreseeable
future of Apache trout to be 30 years based on our ability to reliably
predict the likelihood of future threats as well as the species'
response to future threats. Our analysis of future condition emphasized
the importance of continued management of the conservation barriers and
removal of nonnative trout. Species viability modestly declined in
scenario 3, and increased in scenario 4, due to increases in management
efforts. Scenarios 3 and 4 are both scenarios in which the CMP is being
implemented. In our assessment, we found that the CMP, while voluntary
in nature, plays a vital role in continuing to improve the status of
the Apache trout into the future. For example, WMAT, AZGFD, and the
Service are working together to mechanically remove brook trout from
the upper West Fork Black River population, including Thompson Creek,
in case chemical renovation of this system is not ultimately approved.
This effort represents just one of the ongoing efforts to improve
the species' overall condition, as well as the willingness of Federal,
State, Tribal, and private partners to continue these efforts into the
future. Other collaborative conservation efforts include brook and
brown trout removal projects, fish passage improvements, riparian
habitat restoration projects, and conservation barrier replacements or
old barrier removal projects on Tribal, State, and Federal lands. WMAT
and the Service are currently working to eradicate brown trout from
Aspen, Big Bonito, Coyote, Little Bonito, and Little Diamond creeks.
All partners are working on fish passage improvements including
removing four conservation barriers on Hayground, Home, and Stinky
creeks and replacing six culverts on Paradise and Thompson creeks to
improve fish passage, increase occupied extents, and allow for
metapopulation dynamics among connected populations. Riparian habitat
restoration projects are underway on Boggy and Lofer creeks and being
planned for Flash Creek, South Fork Little Colorado River, and West
Fork Black River. Finally, conservation barrier replacements are
underway (engineering design development or construction contracting
phases) that will protect the populations in Aspen, Boggy/Lofer,
Coyote, Crooked, Flash, Little Bonito, Little Diamond, Ord, Paradise,
and Wohlenberg creeks.
While there is a need to manage Apache trout habitat in ways that
facilitate habitat connectivity and metapopulation dynamics (Williams
and Carter 2009, pp. 27-28), conservation barrier management will
remain important to the conservation of the species. Because the intent
of barriers is to isolate populations of Apache trout from nonnative
trout,
[[Page 54562]]
many populations will have to persist in place rather than shift in
space to adapt to future changes in climate (Thurman et al. 2020,
entire). This may restrict the ability of some populations to adapt in
place to climate change effects. Adaptation potential should be
considered in concert with the reality that many populations reside in
small habitat patches. This can constrain long-term viability and is
one of the trade-offs that comes with isolation management (Fausch et
al. 2009, entire); however, our identification of climate resilient
habitats in our climate analysis did incorporate patch size as a driver
of long-term persistence.
Apache trout populations with high resiliency will continue to be
the focus of active habitat management, such as riparian vegetation
management and habitat restoration, to improve or ensure their climate
resiliency into the 2080s and potentially beyond. Finally, most habitat
patches are not currently limited by warm stream temperatures. Habitat
designated for Apache trout recovery largely occurs in colder, upstream
areas above conservation barriers (Avenetti et al. 2006, p. 213; USFWS
2009, p. 19), and even with increasing stream temperatures through the
foreseeable future many of these areas will not be limited by warmer
temperatures into the 2080s. As described previously, the effect of
temperature on juvenile Apache trout occupancy suggests that many
streams can in fact be too cold, and projections of stream temperature
into the 2080s in some cases increased the amount of suitable habitat
in some streams because of the unimodal response to temperature.
Overall, the signing of the CMP in 2021 which, while subject to
review and termination by the signing parties, ensures that
conservation for the Apache trout will remain in perpetuity. With the
CMP in place, and considering future effects from climate change and
the response of Apache trout to these effects, we conclude that the
Apache trout will exhibit sufficient resiliency, redundancy, and
representation to maintain viability for the foreseeable future.
Accordingly, we conclude that the species is not likely to become in
danger of extinction in the foreseeable future 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
in the foreseeable future throughout all or a significant portion of
its range. Having determined that Apache trout is not in danger of
extinction or likely to become so in the foreseeable future throughout
all of its range, we now consider whether it may be in danger of
extinction (i.e., endangered) or likely to become so in the foreseeable
future (i.e., threatened) in a significant portion of its range--that
is, whether there is any portion of the species' range for which both
(1) the portion is significant; and, (2) the species is in danger of
extinction or likely to become so in the foreseeable future in that
portion. Depending on the case, it might be more efficient for us to
address the ``significance'' question or the ``status'' question first.
We can choose to address either question first. Regardless of which
question we address first, if we reach a negative answer with respect
to the first question that we address, we do not need to evaluate the
other question for that portion of the species' range.
In undertaking this analysis for Apache trout, we choose to address
the status question first. We began by identifying portions of the
range where the biological status of the species may be different from
its biological status elsewhere in its range. For this purpose, we
considered information pertaining to the geographic distribution of (a)
individuals of the species, (b) the threats that the species faces, and
(c) the resiliency condition of populations.
We evaluated the range of the Apache trout to determine if the
species is in danger of extinction now or likely to become so in the
foreseeable future in any portion of its range. Because the range of a
species can theoretically be divided into portions in an infinite
number of ways, we focused our analysis on portions of the species'
range that may meet the definition of an endangered species or a
threatened species. Although we assessed current and future conditions
at a population scale in the SSA report, interactions between
populations within a subbasin can be complex (i.e., in some subbasins,
there are genetic exchanges between populations while in others,
populations are separated by barriers). Thus, to assess these portions
equally, we focus our analysis here at the subbasin scale. That said,
the current and future conditions of the populations will be used to
discuss the conditions of the subbasins.
Within these portions, we examined the following threats: invasive
trout, habitat loss due to wildfire, and the effects from climate
change, including synergistic and cumulative effects. As discussed in
our rangewide analyses, nonnative trout and wildfire are the main
drivers of the species' status.
Looking across the different subbasins, all but one have the mean
GPA of 2.83 or above under its current condition (meaning good
conditions under our conditions metric). When examining future
conditions, even under the worst case scenario where with reduced
management and no CMP, all but one subbasin have a future condition
status of fair. While there are differences in scoring within each
subbasin, at the subbasin scales, these subbasins possess sufficient
resiliency such that we do not consider them to be in danger of
extinction or likely to become so within the foreseeable future. For
these subbasins, we assessed them to possess the same status as our
rangewide analysis.
Out of all the subbasins of the Apache trout, the Diamond subbasin
has the lowest mean GPA of 2.33 under its current condition. However,
under future condition, we project the species will slightly decline
from its current condition under scenario 3. Under both scenarios 3 and
4, the subbasin would be on the lower end of the fair rating.
The major driver of a subbasin's status is its habitat condition
score. Although future condition scoring does not separate demographic
GPA from habitat GPA, we know from the current condition score that the
limiting factor for Apache trout within the Diamond subbasin is habitat
condition. Three of the four populations within the Diamond subbasin
have high demographic GPA with high abundance and multiple age classes.
However, the scores for habitat quality are 2.33, 2.00, 1.83, and 1.83,
due primarily to shorter occupied stream lengths compared to other
populations. Additionally, the streams within the Diamond subbasin
experience a higher percentage of intermittency, meaning that larger
portions of the stream tend to go dry during periods of drought. Given
the continuing effects of climate change, it is likely that these
streams will experience periods with intermittent streamflow in some
reaches into the future.
Although populations of the Apache trout in the Diamond subbasin
are currently rated as being in fair condition, the low habitat quality
(primarily due to occupied stream length being less than 11.25 km,
estimations of intermittent stream proportions, the presence of brown
trout, and current barrier conditions) and the potential for decline
due to climate change could lead to elevated risk to populations in the
foreseeable future in this portion of the range. Work to eradicate (and
prevent reinvasion of) brown trout from two streams in this
[[Page 54563]]
subbasin is underway, which, if successful, would result in higher
habitat scores once completed (with all other scores remaining
unchanged, the subbasin's average habitat GPA would rise to 2.58 once
the work is completed) and would reduce the risk of population declines
in this portion of the range (USFWS 2022b, p. 101). However, these
actions have not yet significantly improved the status of this
subbasin, and we assessed this subbasin to be at elevated risk of
extinction to a degree that it may be in danger of extinction within
the foreseeable future.
Given that the Diamond subbasin may be in danger of extinction
within the foreseeable future, we next evaluated if this portion of the
range was significant. Although every subbasin provides some
contribution to the species' resiliency, representation, and
redundancy, as noted above, the Diamond subbasin populations occupy a
short stream length (30.2 km (18.8 mi)) that comprises a small portion
of the Apache trout's overall range (10.7 percent of the Apache trout's
overall range of 281.5 km (174.9 mi)). Ecologically, the habitats where
these populations are found are not dissimilar to habitats found in the
other subbasins. As in the other subbasins, Apache trout in the Diamond
subbasin are found in headwater streams with shallow depth, relatively
slow-moving water, and coarse, clean gravel streambeds.
The Diamond subbasin is comprised of a mixture of replicate and
relict populations. Although this subbasin contains relict populations,
these and the replicate populations are associated with populations in
the neighboring subbasins of North Fork White River and East Fork White
River. Specifically, relict populations in the adjacent subbasin were
used as founder stocks for the replicate populations in the Diamond
subbasin, and the relict population in the Diamond subbasin was used to
create a replicate population in an adjacent subbasin. Thus, through
the process of replication of populations, the genetic contribution of
the Diamond subbasin is dispersed across other subbasins.
Overall, the Diamond subbasin's short stream length relative to the
species' overall range, lack of ecological uniqueness, close proximity
to other subbasins, and existence of replicate populations lead us to
conclude that this portion of the Apache trout's range is not
significant in terms of its overall contribution to the species'
resiliency, redundancy, and representation. Therefore, because we could
not answer the significance question in the affirmative, we conclude
that the Diamond subbasin does not warrant further consideration as a
significant portion of the range. Therefore, we find that the species
is not in danger of extinction now or likely to become so in the
foreseeable future in any significant portion of its range. This does
not conflict with the courts' holdings in Desert Survivors v.
Department of the Interior, 336 F. Supp. 3d 1131 (N.D. Cal. 2018), and
Center for Biological Diversity v. Jewell, 248 F. Supp. 3d. 946, 959
(D. Ariz. 2017) because, in reaching this conclusion, we did not apply
the aspects of the Final Policy on Interpretation of the Phrase
``Significant Portion of Its Range'' in the Endangered Species Act's
Definitions of ``Endangered Species'' and ``Threatened Species'' (79 FR
37578; July 1, 2014), including the definition of ``significant'' that
those court decisions held to be invalid.
Determination of Status
Our review of the best available scientific and commercial
information indicates that the Apache trout does not meet the
definition of an endangered species or a threatened species in
accordance with sections 3(6) and 3(20) of the Act. In accordance with
our regulations at 50 CFR 424.11(e)(2) currently in effect, the Apache
trout does not meet the definition of an endangered or a threatened
species. Therefore, we propose to remove the Apache trout from the
Federal List of Endangered and Threatened Wildlife.
Effects of This Rule
This proposal, if made final, would revise 50 CFR 17.11(h) by
removing the Apache trout from the Federal List of Endangered and
Threatened Wildlife. Accordingly, we would also remove the Apache trout
from the rule issued under section 4(d) of the Act (``4(d) rule'') at
50 CFR 17.44(a). The prohibitions and conservation measures provided by
the Act, particularly through sections 7 and 9, would no longer apply
to this species. Federal agencies would no longer be required to
consult with the Service under section 7 of the Act in the event that
activities they authorize, fund, or carry out may affect the Apache
trout. No critical habitat has been designated for Apache trout, so
there would be no effect to 50 CFR 17.95. State laws related to the
Apache trout would remain in place, be enforced, and continue to
provide protection for this species.
Editorial Corrections
In this proposed rule, we incorporate editorial corrections to the
4(d) rule set forth at 50 CFR 17.44(a) to provide the correct
scientific names for Lahontan cutthroat trout and Paiute cutthroat
trout. Those scientific names were updated on the List of Endangered
and Threatened Wildlife at 50 CFR 17.11(h) with the 1990 issue of the
Code of Federal Regulations, but the scientific names provided in the
4(d) rule were not updated at that time. This action would correct that
oversight.
Post-Delisting Monitoring
Section 4(g)(1) of the Act requires us, in cooperation with the
States, to implement a monitoring program for not less than 5 years for
all species that have been delisted due to recovery. Post-delisting
monitoring (PDM) refers to activities undertaken to verify that a
species delisted remains secure from the risk of extinction after the
protections of the Act no longer apply. The primary goal of a PDM
program is to monitor the species to ensure that its status does not
deteriorate, and if a decline is detected, to take measures to halt the
decline so that proposing it as an endangered or threatened species is
not again needed. If at any time during the monitoring period data
indicate that protective status under the Act should be reinstated, we
can initiate listing procedures, including, if appropriate, emergency
listing.
The PDM program for Apache trout would monitor populations
following the same sampling protocol used by cooperators prior to
delisting. Monitoring would consist of tracking Apache trout
distribution and abundance and potential adverse changes to Apache
trout habitat due to environmental or anthropogenic factors. Post-
delisting monitoring would occur for a 10-year period, beginning after
the final delisting rule was published, and would include the
implementation of (1) Apache Trout Monitoring Plan (``Monitoring
Plan,'' Dauwalter et al. 2017a, entire) and (2) Apache Trout
Cooperative Management Plan (CMP, Apache Trout CMP Workgroup 2021,
entire) for the duration of the PDM period. Both plans are currently
being implemented and will continue to be implemented into the future.
The Monitoring Plan describes population and habitat survey methods,
data evaluation methods, and monitoring frequency for each population.
The CMP describes roles, responsibilities, and evaluation and reporting
procedures by the cooperators. Together these plans would guide
collection and evaluation of pertinent information over the PDM period
and would be implemented jointly by the Service, WMAT, AZGFD, USFS, and
Trout Unlimited. Both documents will be available upon the
[[Page 54564]]
publication of this proposed rule at https://www.regulations.gov, under
the Docket No. FWS-R2-ES-2022-0115.
During the PDM period, if declines in the Apache trout's protected
habitat, distribution, or persistence were detected, the Service,
together with other PDM partners, would investigate causes of the
declines, including considerations of habitat changes, human impacts,
stochastic events, or any other significant evidence. The outcome of
the investigation would be to determine whether the Apache trout
warranted expanded monitoring, additional research, additional habitat
protection, or relisting as an endangered or threatened species under
the Act. If relisting the Apache trout were warranted, emergency
procedures to relist the species may be followed, if necessary, in
accordance with section 4(b)(7) of the Act.
Required Determinations
Clarity of the Rule
We are required by Executive Orders 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:
(a) Be logically organized;
(b) Use the active voice to address readers directly;
(c) Use clear language rather than jargon;
(d) Be divided into short sections and sentences; and
(e) 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 names 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), Executive Order 13175, and the Department of
the Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with recognized Federal
Tribes 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.
The Apache trout occurs on area managed by the White Mountain
Apache Tribe (WMAT). As noted above, we have coordinated with WMAT in
conserving and protecting the Apache trout's habitat and populations.
Furthermore, WMAT was an invited participant in the development of the
SSA. Going forward, we anticipate our partnership with WMAT to continue
into the future regardless of any potential changes in the Apache
trout's status under the Act.
References Cited
A complete list of all references cited in this proposed rule is
available on the internet at https://www.regulations.gov or upon
request from the person listed under FOR FURTHER INFORMATION CONTACT.
Authors
The primary authors of this proposed rule are staff members of the
Service's Species Assessment Team and the Arizona Fish and Wildlife
Conservation 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, we hereby propose 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
0
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.
Sec. 17.11 [Amended]
0
2. In Sec. 17.11, in paragraph (h), amend the List of Endangered and
Threatened Wildlife by removing the entry for ``Trout, Apache'' under
FISHES.
0
3. In Sec. 17.44, amend the introductory text of paragraph (a) to read
as follows:
Sec. 17.44 Special rules--fishes.
(a) Lahontan cutthroat trout and Paiute cutthroat trout
(Oncorhynchus clarkii henshawi and Oncorhynchus clarkii seleniris).
* * * * *
Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-15689 Filed 8-10-23; 8:45 am]
BILLING CODE 4333-15-P
