Rule2024-19330
Endangered and Threatened Wildlife and Plants; Removal of the Apache Trout From the List of Endangered and Threatened Wildlife
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
September 6, 2024
Effective
October 7, 2024
Issuing agencies
Interior DepartmentFish and Wildlife Service
Abstract
We, the U.S. Fish and Wildlife Service (Service or USFWS), are removing the Apache trout (Oncorhynchus apache), a fish native to Arizona, from the Federal List of Endangered and Threatened Wildlife. Our review indicates that the threats to the Apache trout have been eliminated or reduced to the point that the species no longer meets the definition of an endangered or threatened species under the Endangered Species Act of 1973, as amended (Act). Accordingly, the prohibitions and conservation measures provided by the Act, particularly through section 4 and 7, will no longer apply to the Apache trout.
Full Text
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[Federal Register Volume 89, Number 173 (Friday, September 6, 2024)]
[Rules and Regulations]
[Pages 72739-72757]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2024-19330]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R2-ES-2022-0115; FXES1113090FEDR-245-FF09E22000]
RIN 1018-BG94
Endangered and Threatened Wildlife and Plants; Removal of the
Apache Trout From the List of Endangered and Threatened Wildlife
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service or USFWS), are
removing the Apache trout (Oncorhynchus apache), a fish native to
Arizona, from the Federal List of Endangered and Threatened Wildlife.
Our review indicates that the threats to the Apache trout have been
eliminated or reduced to the point that the species no longer meets the
definition of an endangered or threatened species under the Endangered
Species Act of 1973, as amended (Act). Accordingly, the prohibitions
and conservation measures provided by the Act, particularly through
section 4 and 7, will no longer apply to the Apache trout.
DATES: This rule is effective October 7, 2024.
ADDRESSES: The proposed rule and this final rule, the post-delisting
monitoring plan, the comments we received on the proposed rule, and
supporting documents are available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under
Docket No. FWS-R2-ES-2022-0115.
FOR FURTHER INFORMATION CONTACT: 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,
<a href="/cdn-cgi/l/email-protection#3d54535e525054535a7c675e524f4f7d5b4a4e135a524b"><span class="__cf_email__" data-cfemail="d4bdbab7bbb9bdbab3958eb7bba6a694b2a3a7fab3bba2">[email protected]</span></a>. 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
removal from the Federal Lists of Endangered and Threatened Wildlife
and Plants if it
[[Page 72740]]
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 an endangered species within the
foreseeable future throughout all or a significant portion of its
range). The Apache trout is listed as threatened, and we are delisting
it because we have determined it 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 rule removes the Apache trout from
the List of Endangered and Threatened Wildlife (List) due to the
species' recovery.
The basis for our action. Under the Act, we may determine that a
species is an endangered species or a 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(e) identify four reasons why we might
determine a species shall be delisted: (1) The species is extinct, (2)
the species has recovered to the point at which it no longer meets
thedefinition of an endangered species or a threatened species, (3) new
information that has become available since the original listing
decision shows the listed entity does not meet thedefinition of an
endangered species or a threatened species, or (4) new information that
has become available since the original listing decision shows the
listed entity does not meet thedefinition of a species. Here, we have
determined that the Apache trout has recovered to the point at which it
no longer meets the definition of an endangered species or a threatened
species; therefore, we are delisting it.
Specifically, our analysis indicates that the Apache trout now
consists of multiple, sufficiently resilient populations across
subbasins encompassing a large percentage of the species' historical
range. Due to conservation efforts undertaken to date, the Apache trout
now encompasses 30 confirmed genetically pure populations across 3
basins and 6 subbasins. Twenty-five of the 30 pure populations of
Apache trout are located in whole (22) or in part (3) on Tribal lands,
where longstanding policy has and will continue to result in
significant protections of the watersheds and these populations.
We consider the Apache trout to be a conservation-reliant species,
which we define in this case as a species that has met recovery
criteria but requires continued active management to sustain the
species and associated habitat in a recovered condition (see Scott et
al. 2010, entire), given that the Apache trout requires active
management to maintain suitable habitat. To address this management
need for conservation activities to address long-term management of
this species, the Arizona Game and Fish Department (AZGFD), White
Mountain Apache Tribe (WMAT), the U.S. Forest Service (USFS), Trout
Unlimited, and the Service developed, and are implementing, the Apache
trout Cooperative Management Plan (CMP; USFWS 2021, entire) and are
committed to the continuing long-term management of this species.
Management of conservation barriers and removal of nonnative trout
following the CMP, which will not be impacted by this delisting
determination, will ensure that the Apache trout maintains sufficient
resiliency, redundancy, and representation to maintain viability into
the future.
Previous Federal Actions
Please refer to the proposed rule to delist the Apache trout
published on August 11, 2023, (88 FR 54548) for a detailed description
of previous Federal actions concerning this species.
Peer Review
A species status assessment (SSA) team prepared an SSA report for
the Apache trout (USFWS 2022a, entire). The SSA team was composed of
Service biologists, in consultation with other species experts from
WMAT, AZGFD, 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 and recovery actions under the Act, we solicited independent
scientific review of the information contained in the Apache trout SSA
report. As discussed in the proposed rule, we sent the SSA report to
three independent peer reviewers and received three responses. The peer
reviews can be found at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. In preparing the
proposed rule, we incorporated the results of these reviews, as
appropriate, into the SSA report, which was the foundation for the
proposed rule and this final rule. A summary of the peer review
comments and our responses can be found in the proposed rule (88 FR
54548; August, 11, 2023).
Summary of Changes From the Proposed Rule
In preparing this final rule, we reviewed and fully considered all
comments we received during the comment period from the peer reviewers
and the public on the proposed rule to reclassify the Apache trout.
Minor, nonsubstantive changes and clarifications were made to the SSA
report and this final rule in response to comments. The information we
received during the peer review and public comment period on the
proposed rule did not change our analysis, rationale, or determination
for delisting the Apache trout. Below is a summary of the
clarifications made in this final rule.
(1) We made revisions to the Recovery Plan Implementation, below,
to provide more clarity on various management and conservation actions
that have been taken to benefit the Apache trout. With regard to
management of the Apache trout and Apache trout habitat, we clarified
that: projects on Apache Sitgreaves National Forest (ASNF) lands
require National Environmental Policy Act review; and the WMAT, AZGFD,
ASNF, USFWS, and Trout Unlimited are all signatories to the 2021 Apache
Trout Cooperative Management Plan (USFWS 2021, entire).
(2) We included recent confirmation of the one population listed as
``pure-suspected'' in the SSA report. This population has been analyzed
and was found to be genetically pure since the publication of the
proposed rule on August 11, 2023 (88 FR 54548) (Mussmann 2024, pers.
comm.).
(3) We noted ``put-and-take opportunities'' provided by AZGFD and
WMAT that are intended to generate
[[Page 72741]]
public support for Apache trout recovery.
(4) We clarified that Apache trout recovery streams on Tribal lands
have not and will not be opened for angling in the future according to
longstanding Tribal policy.
(5) Finally, we included information on our post-delisting
monitoring (PDM) plan (Dauwalter et al. 2024, entire) that will start
once the Apache trout is delisted. This plan will be managed and
adhered to by the Service and its partners for at least 10 years.
Specifically, the PDM plan prescribes for monitoring of Apache trout
abundance and for ongoing assessments of conservation barrier
effectiveness.
Summary of Comments and Recommendations
In the proposed rule published on August 11, 2023 (88 FR 54548), we
requested that all interested parties submit written comments on the
proposal by October 10, 2023. We also contacted appropriate Federal and
State agencies, Tribal entities, scientific experts and organizations,
and other interested parties and invited them to comment on the
proposal. A newspaper notice inviting general public comment was
published in the White Mountain Independent on August 18, 2023. We did
not receive any requests for a public hearing. All substantive
information received during the comment period has either been
incorporated directly into this final determination or is addressed
below.
Public Comments
We reviewed all public comments for substantive issues and new
information regarding the species. Substantive comments we received
during the comment period are addressed below.
(1) Comment: Three commenters expressed opposition to delisting the
Apache trout based on the projected effects of climate change and
associated effects on Apache trout habitat. The noted effects include
reduced habitat suitability, diminished stream volume, and less
precipitation. Two commenters cited recent peer-reviewed published
projections by Dauwalter (2023 et al., entire) that apply these effects
specifically to Apache trout and regionally to the southwestern United
States. The third commenter stated that the implication of warmer
upstream temperatures being a benefit to Apache trout populations in
those portions of streams was incorrect.
Our response: The SSA report examined in depth the effects of
climate change and associated effects on Apache trout habitat and did
not find these effects to impact the resiliency of the species in the
foreseeable future. Specifically, as we stated in the SSA report (USFWS
2022a, pp. 51, 135-140), the model suggests that most streams currently
occupied by Apache trout, or those currently unoccupied but designated
as recovery streams, are not temperature limited. Suitability only
improves when 2080s projections of temperature alone are considered,
because some headwater reaches appear to be too cold, currently, for
occupancy. That is, cold temperatures can be limiting to Apache trout
populations in some streams, and any warming may benefit them in
headwater reaches--at least until the 2080s. It is only when future
changes in precipitation are considered, as well, that habitat
suitability decreases during 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). In the Summary of Biological Status
and Threats section of this final rule, we expanded our discussion of
climate change as a threat.
In response to the reference to Dauwalter (2023, entire), we note
that the cited manuscript was based on appendix C of the SSA report
(USFWS 2022a, pp. 133-137) and was published by Apache trout SSA core
team members following completion of the SSA report. Dauwalter et al.
(2023, entire) noted that most Apache trout populations are isolated
upstream of barriers to nonnative trout in stream reaches that are
currently thermally suitable with respect to mean July temperatures and
concluded those habitats would remain suitable into the 2080s. Cold
headwater reaches are projected to warm, becoming more suitable in the
2080s. Thus, intentional isolation and the resultant truncated
downstream distributions of Apache trout populations in headwater
streams explain the nominal effect of projected temperature increases
due to climate change on this cold-adapted salmonid. Standardized model
parameters suggest that future declines in precipitation, manifested
through reduced snowpack and its influence on streamflows, will play a
larger role than temperature in the suitability--and, thus,
resiliency--of Apache trout habitats at least into the 2080s.
(2) Comment: Two commenters stated that the delisting is premature
because of impacts to Apache trout habitat caused by grazing by horses
and livestock. Examples of these impacts may include eroded soils and
streambanks, damaged riparian vegetation, widening of streams, effects
on water depth and temperature, and contamination of streams by fecal
material. One commenter stated that current land management plans by
the USFS are inadequate to address these impacts. They further
identified the western Black River watershed as a particular location
where severe stream degradation has occurred due to grazing by horses
on Tribal land.
Our response: Stream habitat quality was assessed and classified in
the Current Conditions section of the SSA report (USFWS 2022a, pp. 61-
96) and these assessments considered and reflected impacts from
stochastic events (e.g., wildfire) and a variety of anthropogenic
factors (e.g., road crossings, developed floodplains, logging, animal
use). The SSA report section on Future Conditions (USFWS 2022a, pp. 97-
106) included analysis of future conditions from environmental change
and management actions and the projected influences on the species'
ability to sustain populations in the wild over defined timeframes.
Thirty-seven distinct threat factors were considered in this analysis,
with Apache trout experts considering continued conservation actions
(e.g., barrier construction and maintenance, chemical and mechanical
removal of invasive species, habitat restoration, watershed management)
and wildfires as the most important factors affecting the future
condition of the Apache trout.
Grazing management was ultimately ranked as the 14th most important
factor affecting the future condition of Apache trout. There are few
livestock grazing allotments associated with Apache trout recovery
streams, and the USFS engages in active management to remove feral
horses and stray cattle where they occur outside of authorized areas.
There are areas where habitat quality has been degraded by legacy
grazing and other anthropogenic factors, especially in sensitive wet
meadow habitats. In addition, Apache trout recovery partners are
currently pursuing funding to address degraded habitats with ungulate
exclosure areas, riparian plantings, and instream habitat restoration
projects. Current proposals are focused on the Black River and Little
Colorado River watersheds along Burro, Centerfire, Hayground, and
Thompson creeks and South Fork Little Colorado River. Funding has
already been secured and projects begun on Boggy/Lofer and Flash creeks
on Tribal lands. Additionally, it is important to emphasize that
despite certain degraded habitats, due in part to possible
[[Page 72742]]
anthropogenic factors including grazing that have been in place since
the species was listed, populations of the species have grown to meet
the recovery criteria. Accordingly, we find that because the species
met recovery criteria despite the effects of grazing activities, and
because ongoing and future restoration projects and active grazing
management will decrease the effects of this stressor in the future,
delisting is not premature due to potential impacts of grazing.
(3) Comment: One commenter stated that populations under 500
individuals are at higher risk from demographic and genetic
stochasticity, as well as stochastic events such as stream drying,
fire, inbreeding, and low genetic variation.
Our response: The population estimates presented in the SSA report
are strictly estimates of adult population size. Total population size
estimates, which are available for some populations, are generally much
larger than the estimates of adult population size presented in the SSA
report. Although we contend that there is uncertainty about the exact
threshold under which Apache trout populations are at higher risk from
stochastic events, we generally agree with this comment, which is why
this concept was discussed in the SSA report's Executive Summary
section on resiliency (USFWS 2022a, p.7), as well as the sections on
population size (USFWS 2022a, p.43), effective population size (USFWS
2022a, p.44), habitat connectivity and metapopulation dynamics (USFWS
2022a, p.45), habitat factors (USFWS 2022a, p.75), and population
resiliency (USFWS 2022a, p.78).
(4) Comment: One commenter stated that the 30-year, 6-generation
timeframe used for our future condition analysis is arbitrary and not
based on anything biologically meaningful. They stated that we have
used longer timeframes when analyzing the effects of climate change and
other long-term impacts for other species' classification analyses.
Our response: The SSA framework documentation suggests that a
meaningful timeframe should encompass multiple generations when
considering a species' future condition and status (USFWS 2016, p. 18).
We found that 30 years, or 6 generations of the Apache trout is a
meaningful timeframe in which to analyze future condition because
within this timeframe it is likely that the primary threats of
nonnative trout and climate change will continue to be relevant to the
species and it is biologically reasonable to assess the species'
response to these threats within this timeframe. We have a high level
of confidence in the results of our analysis of these threats and
responses within this timeframe, and our confidence in the results of
an analysis extended beyond this timeframe decreases. Additionally,
this timeframe allows us to reasonably forecast upcoming management
activities as they will be implemented through the CMP.
(5) Comment: One commenter stated that the information and data we
used to assess stream temperatures are outdated and that predicted
higher stream temperatures will lead to an increase of invasive trout
species in Apache trout streams.
Our response: We used the best available in situ temperature
monitoring data collected by the Apache-Sitgreaves National Forests on
Apache trout recovery streams (2013-2018) and a widely-used stream
temperature model (NorWeST; Isaak et al. 2017, entire) that contained
projections into the 2080s (GCM projections of a ten-model ensemble and
A1B emissions scenario; Isaak et al. 2017) to understand future habitat
suitability--an approach that was subjected to peer review and was
published (Dauwalter et al. 2023, entire).
Thermal tolerances between trout species are similar, and recovery
streams are suitable at this time and expected to remain so well into
the future. We view invasive trout as one of the primary ongoing
threats to this species and have developed short- and long-term plans,
which are described in the CMP and Apache Trout Monitoring Plan, to
monitor for and manage this threat long-term (Apache Trout CMP
Workgroup 2021, entire; Dauwalter et al. 2024, entire). Since 2015,
recovery partners have eradicated invasive trout in Crooked and Flash
creeks, and likely eradicated them from Aspen (formerly Squaw) and
Paradise creeks during 2022. Much progress has been made in suppressing
brook trout in the upper West Fork Black River population area, and in
2023, YY-male brown trout stocking began to ensure success of this
effort. Additional nonnative trout removal projects will begin as the
ongoing projects are completed.
In addition to these projects, recovery partners are supporting
efforts to develop a YY-male brown trout broodstock for future use in
eradication projects. Construction of a new conservation barrier on Big
Bonito Creek has begun, and engineering designs for new conservation
barriers on Aspen, Crooked/Boggy/Lofer, Flash, Little Bonito, Little
Diamond/Coyote, Ord, Paradise, and Wohlenberg creeks have been acquired
or are expected to be finalized during 2024. Finally, both the CMP and
the Apache Trout Monitoring Plan (Apache Trout CMP Workgroup 2021,
entire; Dauwalter et al. 2024, entire) detail our future invasive trout
surveillance and Apache trout monitoring plans.
(6) Comment: One commenter stated that the SSA report indicates
that 11 of 31 Apache trout streams lack evidence of hybridization with
other trout species, however the proposed rule does not discuss this.
Our response: Table 11 in the SSA report (USFWS 2022a pp. 8-9)
shows that 29 populations are ``pure-tested'' with another ``pure-
suspected.'' Tissue samples from the ``pure-suspected'' population were
collected and submitted for genetic analyses, and preliminary results
indicate genetic purity of this population as well (Mussman pers. comm.
2024). Table 15 in the SSA report (USFWS 2022a, p. 104) also
demonstrates the same information: there are 29 populations with a
genetic score of 4 (pure-tested) and 1 with a score of 3 (pure-
suspected). These are the 30 populations (now all confirmed to be pure)
referenced throughout the SSA report, the 5-year status review, the
proposed rule, and this final rule.
(7) Comment: One commenter stated that protection of Apache trout
habitat in the West Fork of the Black River from exotic trout has not
been accomplished as promised by the AZGFD and as required by the
Central Arizona Project (CAP) settlement agreement. They indicated
doubt that this protection would be accomplished by a conservation
management plan.
Our response: The 2008 Reinitiated Biological Opinion on
Transportation and Delivery of Central Arizona Project Water to the
Gila River Basin in Arizona and New Mexico and its Potential to
Introduce and Spread Nonindigenous Aquatic Species (USFWS 2008, entire)
includes a list of barriers to be constructed by U.S. Bureau of
Reclamation (Reclamation) and states: ``Reclamation will construct a
single fish barrier at these sites, of a design similar to those
completed on Aravaipa, Sonoita, or Fossil Creeks. Siting and design
will be subject to agreement between Reclamation and the Service, with
appropriate review and input from AZGFD, the landowner, and experts on
southwestern fishes, hydrology, and nonindigenous species invasions.
Reclamation will maintain the barriers in good operating condition for
the expected 100-year life of CAP. Management actions upstream of these
barriers (e.g., stream renovation, species repatriation) will be the
responsibility of
[[Page 72743]]
the Service or AZGFD but may be funded through the existing Fund
Transfer Program. Reclamation or its designate will monitor fish
populations upstream of each constructed barrier for a period of five
years following construction, unless such monitoring is redundant to
that conducted by other agencies. Monitoring is intended to evaluate
the success of the barriers in preventing invasions of nonindigenous
fishes.''
AZGFD is not required by the referenced agreement to eradicate
invasive fish from West Fork Black River, but has been working with
recovery partners to do so. They have been working with White Mountain
Apache Tribe (WMAT) Game and Fish Department and the Service on
intensive mechanical removal of brook trout in the West Fork Black
River (upper) and Thompson Creek (upper) recovery population areas, and
much progress has been made to eradicate them since 2021. These three
recovery partners proposed chemical renovation of this system during
2022, but they changed approaches due to public concerns raised during
meetings about the project. Brook trout are much less abundant in the
West Fork Black River (upper) recovery area and have been eradicated
from the Thompson Creek (upper) population area, following several
years of intensive mechanical removal efforts (2021-present).
(8) Comment: Two commenters expressed concern over the
effectiveness of protective barriers in keeping Apache trout
populations free of nonnative trout. One commenter stated that all
protective barriers would eventually be breached by exotic trout, and
the other commenter stated that most Apache trout populations are
isolated above protective barriers and are all at risk of invasion by
invasive trout.
Our response: In the SSA report we discuss how fish passage
barriers have long been used as a conservation tool to protect Apache
trout populations from invading nonnative fishes that occur and are
naturalized from historical stocking practices (Robinson et al. 2004,
entire; Avenetti et al. 2006, entire). A short-term evaluation of
effectiveness of barriers protecting Apache trout populations found
that only 1 of 1,436 salmonids marked downstream were collected
upstream of the evaluated barriers over a 3-year period. Despite short-
term effectiveness, long-term evaluation was needed (Avenetti et al.
2006, entire). Maintenance on barriers is commonly conducted by
managers when effectiveness is questionable due to physical integrity
or flow patterns, when channel migration compromises structural
integrity, or for other reasons.
In addition, barrier design has sometimes been inadequate. Large
trout have been observed jumping step pools associated with a 1-meter
(m) barrier on Fish Creek during high flows, suggesting passage was
likely at high flows and that the design was inadequate (Avenetti et
al. 2006, pp. 214-215). Recent barrier assessment included an engineer
review and design modification suggestions that have informed barrier
modification and maintenance, and recent barriers have been designed to
withstand higher flows to ensure protection of Apache trout populations
above those barriers (AZGFD and USFWS 2015, entire). The SSA report
shows that 19 of 30 pure populations are free of nonnative trout.
However, considering recent apparent eradications in Aspen (pending)
and Bear Wallow (confirmed) creeks, 21 populations are now free of
nonnative trout. Conservation barriers have been critical to recovery
of Apache trout and other native trout recovery efforts.
Brown trout were eradicated from Crooked Creek in 2015 after 13
years of mechanical removal effort. Although the barrier protecting
that population has not been replaced or modified since, the Apache
trout population above that site has remained free of brown trout and
their abundance has increased 379 percent: adult Apache trout abundance
was estimated at 301 adults in 2016 and 1,444 adults in 2023.
Similarly, abundance of Apache trout in Paradise Creek increased from
an estimated 11 adults in 2018 to 164 adults in 2023 concomitant with
brown trout eradication efforts, and this population will be augmented
with additional Apache trout from Deep Creek to address genetic
concerns due to low population size around 2018. Finally, abundance of
Apache trout in Bear Wallow Creek increased from an estimated 384
adults in 2020 to 1,542 adults in 2023 following nonnative trout
eradication. It is impossible to overstate the importance of
conservation barriers in nonnative trout management within the context
of native trout recovery efforts in the West. Recovery partners have
demonstrated over the last two decades that they understand how to
build and maintain durable conservation barriers and address nonnative
trout invasions when they occur.
(9) Comment: One commenter stated that, in general, current land
management plans being implemented by the USFS are generally vague and
are not enforceable. They stated that ``desirable conditions,'' as
outlined in Apache-Sitgreaves National Forests (ASNF) Land Management
Plan are too broad and may not occur within timeframes beneficial to
Apache trout. They identified the Black River Watershed Restoration
Project as an example of how ongoing incompatible land uses (i.e.,
cattle grazing) have prevented streams from being restored. The
commenter also stated that the conservation management plan described
in our proposed rule is not enforceable and will open Apache trout
stream habitat to further degradation if the species is delisted.
Our response: As discussed in this final rule in the Recovery
Criteria section, although the CMP is a voluntary agreement, we
anticipate the plan will be implemented into the foreseeable future.
Signatories of the CMP all have pre-existing legal authority for land
management and wildlife management across the entire range of the
Apache trout. Furthermore, signatories to the plan have more than a 40-
year track record of active, effective, and continuous voluntary Apache
trout conservation work demonstrating an enduring commitment to the
conservation of this species. The Apache Trout Recovery Plan and the
CMP (USFWS 2009, entire; Apache Trout Cooperative Management Plan
Workgroup 2021, entire) describe ways to enhance or restore stream and
riparian habitats. Apache trout recovery partners (WMAT, AZGFD, USFWS,
USFS, and Trout Unlimited) indicated their commitment to ensure the
long-term persistence of Apache trout, restore and maintain quality
instream habitats, ensure that land management is compatible with
functioning watershed conditions, and provide and enhance sportfishing
opportunities for Apache trout.
The SSA report analysis of 37 distinct threat factors identified
grazing management as the 14th most important factor affecting the
future condition of Apache trout. Additionally, as discussed above in
comment response (2), there are few active livestock grazing allotments
associated with Apache trout recovery streams and the USFS engages in
active management to remove feral horses and stray cattle where they
occur outside of authorized areas. The actions being undertaken to date
to address degradation to habitat due to grazing have not impeded the
species from achieving recovery. There are Apache trout habitat areas
where habitat quality has been degraded by legacy grazing, especially
in sensitive wet meadow habitats, and much of that area has already
been protected with fencing exclosures.
[[Page 72744]]
Projects for new and rebuilt fencing exclosures of sensitive
habitats and riparian plantings are planned on the Apache-Sitgreaves
National Forests and Tribal lands. For example, Apache trout recovery
partners are working cooperatively on projects to address degraded
habitats with ungulate exclosure areas, riparian plantings, and
instream habitat restoration projects along Burro, Centerfire,
Hayground, and Thompson creeks, West Fork Black River, and South Fork
Little Colorado River on the Apache Sitgreaves National Forests.
Similar projects have already begun along Flash and Boggy/Lofer creeks
on Tribal land. National Environmental Policy Act review for several of
these beneficial projects fall under the umbrella of the Black River
Watershed Restoration Project which describes many tools for improving
watershed condition in the project area and are consistent with the
objectives of the Apache-Sitgreaves National Forests Land Management
Plan.
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 2022a, entire) and the revised recovery plan for
Apache trout (USFWS 2009, entire), which are available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R2-ES-2022-0115. A summary of
that information is presented here.
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 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 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 Lists of Endangered and
Threatened Wildlife and Plants.
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 of the criteria in a recovery plan
being fully met. For example, one or more criteria may be exceeded
while other criteria may not yet be accomplished. 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 Act's 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 of 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). To
achieve recovery, the recovery plan identified criteria that 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, the AZGFD, and the
WMAT to monitor, prevent, and control disease and/or causative agents,
parasites, and pathogens that may threaten Apache trout.
[[Page 72745]]
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, the 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 for
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 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). Projects on ASNF lands also
require National Environmental Policy Act review. WMAT also has land
management plans to protect Apache trout populations. Alteration of
logging practices, road 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).
The WMAT, AZGFD, ASNF, USFWS, and Trout Unlimited all signed the
2021 Apache Trout Cooperative Management Plan that has no expiration
date and details how each agency will use their management authorities
to conserve, protect, and manage Apache trout populations and habitat
into the future. WMAT has sovereign authority to regulate fishing on
the Fort Apache Indian Reservation which comprises 76 percent of Apache
trout habitat. WMAT laws and regulations instituted land and stream
closures prohibiting sportfishing of relict populations long before the
Apache trout received protection under the Endangered Species Act. WMAT
continues to prohibit sportfishing of recovery populations, and this
policy is not expected to change. Additionally, the AZGFD provides for
the continued protection and conservation of the Apache trout in the
Arizona Wildlife Conservation Strategy (AZGFD 2022, entire).
Delisting Criterion 2: Thirty discrete populations of genetically
pure Apache trout have been established and determined to be self-
sustaining. This criterion has been met.
Compared to the time of listing when we identified 14 genetically
pure populations, currently, the Apache trout consists of 30
genetically pure populations. The one population that was described as
``pure-suspected'' in the SSA report and proposed rule has been since
analyzed and was found to be genetically pure (Mussmann 2024, pers.
comm). 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 both 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 to 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 conservation barriers prevent 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 recovery streams on Tribal lands have not and will not
be opened for angling in the future according to longstanding Tribal
policy. Twenty-five of the 30 pure populations of Apache trout are
located in whole (22) or in part (3) on Tribal lands accounting for
approximately 76 percent of all occupied Apache trout recovery habitat.
Apache trout streams on national forest lands are protected with
fishing closures when populations are small and vulnerable, and with
catch-and-release regulations in larger populations where harvest could
still negatively impact the population. To generate public support for
recovery of the species, AZGFD does provide put-and-take opportunities
for Apache trout in Silver Creek, East Fork Black River, and West Fork
Little Colorado River. WMAT provides similar opportunities 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 signed the 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.
[[Page 72746]]
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. The
recovery partners are constructing and maintaining conservation
barriers, removing invasive species, planning for restocking Apache
trout as needed, and repairing and restoring habitats. Third, the
conservation mission and authorities of these agencies authorize this
work even after the species is delisted. Once the Apache trout is
delisted the PDM plan will be initiated and will be adhered to by the
CMP signatories and other recovery partners for at least 10 years
(Dauwalter et al. 2024, entire). Specifically, the PDM plan prescribes
for monitoring of Apache trout populations to ensure that the number of
fish in populations remains stable and prescribes for ongoing
assessments of conservation barrier effectiveness in protecting Apache
trout from nonnative trout species. 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. On April 5, 2024, 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 what criteria we apply when
designating listed species' critical habitat (89 FR 23919). This final
rule is now in effect and is incorporated into the current regulations.
Our analysis for this decision applied our current regulations. Given
that we proposed delisting this species under our prior regulations
(revised in 2019), we have also undertaken an analysis of whether the
decision would be different if we had continued to apply the 2019
regulations and we concluded that the decision would be the same. The
analyses under both the regulations currently in effect and the 2019
regulations are available on <a href="https://www.regulations.gov">https://www.regulations.gov</a>.
The Act defines an ``endangered species'' as a species that is in
danger of extinction throughout all or a significant portion of its
range, and a ``threatened species'' as a species that is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range. The Act requires that we
determine whether any species is an endangered species or a threatened
species because of any of the following factors:
(A) The present or threatened destruction, modification, or
curtailment of its habitat or range;
(B) Overutilization for commercial, recreational, scientific, or
educational purposes;
(C) Disease or predation;
(D) The inadequacy of existing regulatory mechanisms; or
(E) Other natural or manmade factors affecting its continued
existence.
These factors represent broad categories of natural or human-caused
actions or conditions that could have an effect on a species' continued
existence. In evaluating these actions and conditions, we look for
those that may have a negative effect on individuals of the species, as
well as other actions or conditions that may ameliorate any negative
effects or may have positive effects. 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.
The Act does not define the term ``foreseeable future,'' which
appears in the statutory definition of ``threatened species.'' Our
implementing regulations at 50 CFR 424.11(d) set forth a framework for
evaluating the foreseeable future on a case-by-case basis which is
further described in the 2009 Memorandum Opinion on the foreseeable
future from the Department of the Interior, Office of the Solicitor (M-
37021, January 16, 2009; ``M-Opinion,'' available online at <a href="https://www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37021.pdf">https://www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37021.pdf</a>).
The foreseeable future extends as far into the future as we can make
reasonably reliable predictions about the threats to the species and
the species' responses to those threats. We need not identify the
foreseeable future in terms of a specific period of time. We will
describe the foreseeable future on a case-by-case basis, using the best
available data and taking into account considerations such as the
species' life-history characteristics, threat-projection timeframes,
and environmental variability. In other words, the foreseeable future
is the period of time over which we can make reasonably reliable
predictions. ``Reliable'' does not mean ``certain''; it means
sufficient to
[[Page 72747]]
provide a reasonable degree of confidence in the prediction, in light
of the conservation purposes of the Act.
Analytical Framework
The SSA report documents the results of our comprehensive
biological review of the best scientific and commercial data regarding
the status of the species, including an assessment of the potential
stressors to the species. The SSA report does not represent our
decision on whether the species should be delisted. 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 Apache trout's viability, we used the three
conservation biology principles of resiliency, representation, and
redundancy (Smith et al. 2018, 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, pathogen). 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 individual 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, which we then used to inform our regulatory decision.
The following is a summary of the key results and conclusions from
the SSA report; the full SSA report can be found on the Service website
at <a href="https://ecos.fws.gov/ecp/species/3532">https://ecos.fws.gov/ecp/species/3532</a> and at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R2-ES-2022-0115.
Summary of Biological Status and Threats
In this discussion, we review the biological condition of the
Apache trout 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. In addition, the SSA
report documents our comprehensive biological status review for the
species, including an assessment of the potential threats to the
species. The following is a summary of this status review and the best
available information gathered since that time that have informed this
decision.
The primary threats affecting the Apache trout are the invasion of
nonnative trout species into Apache trout habitat 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 compete with the
Apache trout, and certain species have been known to prey on the Apache
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 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 Apache trout 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
Apache trout at the site scale in fish surveys (USFWS 2022a, 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 the reason 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 in 1993 showed only 11 of 31
streams were deemed to be generically pure (Carmichael et al. 1993,
[[Page 72748]]
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). The proposed delisting rule for Apache trout indicated that
there were 29 genetically pure populations (88 FR 54548; August 11,
2023); one population described as ``pure-suspected'' in the proposed
delisting rule has since been confirmed to be genetically pure.
Currently, the Apache trout consists of 30 genetically pure
populations.
Inbreeding and Low Genetic Diversity
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 one 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 a few hundred
individuals, with an unknown subset successfully reproducing. No
studies have evaluated inbreeding in Apache trout populations, or how
genetic management (e.g., genetic rescue) may benefit Apache trout
populations, and these topics remain of management interest (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 (U.S. Global Change Research
Program 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. 2017a, 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. 210-211; 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 2022a, 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 percent of all occupied patches occurred in reaches at or
below 16.5 degrees Celsius ([deg]C) (61.7 degrees Fahrenheit ([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.
Most Apache trout habitat patches are not currently limited by warm
stream temperatures because the habitat designated for species recovery
is upstream of fish passage barriers (Avenetti et al. 2006, p. 213;
USFWS 2009, p. 19; USFWS 2022b, pp. 118-127). Based on our analysis,
these habitat patches are far enough upstream to also not be limited by
warm stream temperatures into the 2080s. Some streams may even be
currently limited by cold temperatures for juvenile Apache trout, and
these areas may in fact benefit from warmer stream temperatures at
least up until the 2080s.
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
[[Page 72749]]
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 Efforts and Regulatory Mechanisms
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 past and ongoing conservation efforts for
Apache trout, 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 of signed parties. 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 9 Apache trout streams, with successful eradication
suspected in some streams that will be later confirmed with future
electrofishing or environmental DNA 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). In contrast, 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; 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 to 200 fish have been used to establish
populations, but there is evidence that this 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 2021, p. 13).
Habitat Management and Restoration
Past habitat surveys and anecdotal observations 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 30 genetically pure populations, 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 protect Apache trout populations
and implement 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; USFWS 2009, p. 23).
The Southwest Region of the USFS 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.
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
[[Page 72750]]
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 several years of incorporating
wild milt (fish semen) into the broodstock program (2017-present).
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. 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 continue to 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 individual fish to other streams or
hatcheries with suitable isolation facilities until they can be
repatriated into their original or an alternate site (USFWS 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 stream
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 suggests 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 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 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.
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 (0.6 mi) 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
[[Page 72751]]
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
The resiliency of Apache trout populations (and habitats) was
assessed using a 4.0 grading scale and grade-point-average (GPA)
framework. Using this framework, each Apache Trout population received
a grade and grade point equivalents based on the current condition of
the three demographic and six habitat factors described above. The
condition of each factor was graded based on the results of expert
elicitation (see USFWS 2022a, pp. 85-96 for how this grading scale was
used to evaluate Apache trout population 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, 30 populations of Apache trout are known to be 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 genetically
pure Apache trout populations to have adult (greater than 130-mm [5.1
in] TL) population sizes of between 100 and 1,000 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). 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 km (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 (59.9 [deg]F)
for relict and replicate populations, whereas unoccupied streams and
hybrid populations had warmer maximum mean July temperatures up to 17.5
[deg]C (63.5 [deg]F). 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; 31 of these 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 30 genetically pure Apache
trout populations averaged 2.89 (B average) on a 4.0 scale. 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. Unoccupied streams (e.g., Home Creek) had demographic GPAs
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
Redundancy and representation and 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. 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).
[[Page 72752]]
Representation was based on presence of genetically pure relict
populations from each subbasin.
Tracking the redundancy and representation 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 nine 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
five of six 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 be relevant to 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.
Continued implementation of the CMP will actively manage threats to
Apache trout including the presence 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, recovery partners will
continue to undertake successful conservation actions such as
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 continue to prevent hybridization of the Apache trout
with other trout species, as well as to prevent competition with and
predation by other fish species.
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 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 2022a, 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 final 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 (e.g., 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 WMAT
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). This scenario
represented the status quo scenario with approximately the same level
of resources and management action as a 2000-2020 baseline.
<bullet> Barrier installation and maintenance continues at 2000-
2020 levels. The number of viable Apache trout populations and
metapopulations
[[Page 72753]]
increases to meeting recovery goals and is maintained after delisting.
<bullet> Effectiveness of land management policies for stream
ecosystem and threatened species is initially maintained through
delisting 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.
<bullet> 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 WMAT continues. Legislation emerges resulting in new
funding sources for fish habitat projects (e.g., National Fish Habitat
Act), and there is broad implementation of the Four Forest Restoration
Initiative, Black River Restoration Environmental Assessment, and FAIR
Forest Management Plan (fuels management) that are beneficial to
watershed functional conditions and reduced wildfire risk.
<bullet> Barrier installation and maintenance increase 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 to meet and exceed recovery goals.
<bullet> Effectiveness of land management policies for stream
ecosystem and threatened species is initially maintained through
delisting 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.
<bullet> 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 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 and the management of threats
to Apache trout. 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
[[Page 72754]]
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 that are far enough upstream to not be temperature limiting
now or into the 2080s (Avenetti et al. 2006, p. 213; USFWS 2009, p. 19;
USFWS 2022b, pp. 118-127). 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 2022a, 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 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 the Apache Trout's 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 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 30 genetically pure
populations across 3 basins and 6 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 and will continue to contribute 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 higher.
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
[[Page 72755]]
individual subbasins. Overall, the presence of 30 populations across
six 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 met all criteria that the
recovery plan recommended for delisting. This represents a significant
recovery of the species. Recovery plan criteria are meant to function
as guidance for recovery rather than hard metrics that must be met.
Instead, we 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, and because it is a timeframe in which we
can reasonably forecast upcoming management activities as they will be
implemented through the CMP. 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 USFWS are currently 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 conservation
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 USFWS 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 that will protect the populations in
Aspen, Boggy/Lofer, Coyote, Crooked, Flash, Little Bonito, Little
Diamond, Ord, Paradise, and Wohlenberg creeks.
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. 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 ensures that conservation
for the Apache trout will remain for the long-term. 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, and thus does not meet
the definition of a threatened species, 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 the 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,
[[Page 72756]]
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, 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 Diamond subbasin remains 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 GPAs, 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 (7
mi), 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 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 2022a, 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 extirpation to a degree that this portion of the range 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, proximity to
other subbasins, and existence of replicate populations lead us to
conclude that this portion of the Apache trout's range does not
represent a significant portion of the range; therefore, we find that
there are no portions of the species' range that warrant further
consideration, and the species is not in danger of extinction 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, 321 F. Supp. 3d 1011, 1070-74
(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 courts' 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 has recovered to the point at which it no longer meets the
definition of an endangered species or a threatened species. Therefore,
we are removing the Apache trout from the Federal List of Endangered
and Threatened Wildlife.
Effects of This Rule
This rule revises 50 CFR 17.11(h) by removing the Apache trout from
the Federal List of Endangered and Threatened Wildlife. On the
effective date of this rule (see DATES, above), the prohibitions and
conservation measures provided by the Act, particularly through
sections 7 and 9 or any 4(d) rule, will no longer apply to the Apache
trout. Federal agencies will 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.
[[Page 72757]]
This rule will also remove the Federal regulations related to the
Apache trout's 4(d) rule at 50 CFR 17.44(a).
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 recovered. Post-delisting monitoring (PDM)
refers to activities undertaken to verify that a species delisted due
to recovery remains secure from the risk of extinction after the
protections of the Act no longer apply. The primary goal of a PDM 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 endangered or threatened 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.
We have prepared a PDM plan for the Apache trout. We published a
notice of availability of a draft PDM plan with the proposed delisting
rule (88 FR 54548; August 11, 2023), and we did not receive any
comments on the plan. Therefore, we consider the plan final. As
discussed in the proposed rule, the PDM plan for Apache trout will
monitor populations following the same sampling protocol used by
cooperators prior to delisting. Monitoring will 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 will occur for a 10-year period, beginning
after the final delisting rule is published, and will include the
implementation of (1) Apache Trout Monitoring Plan (``Monitoring
Plan,'' Dauwalter et al. 2017b, entire) and (2) Apache Trout CMP,
Apache Trout Cooperative Management Plan 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 will guide
collection and evaluation of pertinent information over the PDM period
and will be implemented jointly by the USFWS, WMAT, AZGFD, USFS, and
Trout Unlimited. Both documents will be available upon the publication
of this rule at <a href="https://www.regulations.gov">https://www.regulations.gov</a>, 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
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951, May 4, 1994), Executive Order 13175
(Consultation and Coordination with Indian Tribal Governments), the
President's memorandum of November 30, 2022 (Uniform Standards for
Tribal Consultation; 87 FR 74479, December 5, 2022), and the Department
of the Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with federally recognized
Tribes and Alaska Native Corporations 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 WMAT. As noted
above, we have coordinated with WMAT in conserving and protecting the
Apache trout's habitat and populations, and we have coordinating with
WMAT throughout the development of the PDM plan. Furthermore, WMAT
participated 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 references cited in this rulemaking is available
on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> and upon request from
the Arizona Ecological Services Office (see FOR FURTHER INFORMATION
CONTACT).
Authors
The primary authors of this rule are staff members of the Service's
Species Assessment Team and the U.S. Fish and Wildlife Service 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.
Regulation Promulgation
Accordingly, we 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; 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, revise the heading of paragraph (a) to read as
follows:
Sec. 17.44 Species-specific 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. 2024-19330 Filed 9-5-24; 8:45 am]
BILLING CODE 4333-15-P
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