[Federal Register Volume 87, Number 26 (Tuesday, February 8, 2022)]
[Proposed Rules]
[Pages 7077-7079]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-02422]



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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2021-0153; FF09E21000 FXES1111090FEDR 223]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
for the Sonoran Desert Tortoise

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notification of finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list the Sonoran desert tortoise 
(Gopherus morafkai) as an endangered or threatened species under the 
Endangered Species Act of 1973, as amended (Act). After a thorough 
review of the best available scientific and commercial information, we 
find that it is not warranted at this time to list the Sonoran desert 
tortoise. However, we ask the public to submit to us at any time any 
new information relevant to the status of the Sonoran desert tortoise 
or its habitat.

DATES: The finding in this document was made on February 8, 2022.

ADDRESSES: A detailed description of the basis for this finding is 
available on the internet at https://www.regulations.gov under Docket 
No. FWS-R2-ES-2021-0153.
    Supporting information used to prepare this finding is available by 
contacting the person listed under FOR FURTHER INFORMATION CONTACT. 
Please submit any new information, materials, comments, or questions 
concerning this finding to the person listed under FOR FURTHER 
INFORMATION CONTACT.

FOR FURTHER INFORMATION CONTACT: Mark Lamb, Arizona Ecological Services 
Field Office, 9828 North 31st Ave. C3, Phoenix, AZ 85051-2517; 
telephone 602-242-0210. Persons who use a telecommunications device for 
the deaf (TDD) may call the Federal Relay Service at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Under section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.), we 
are required to make a finding whether or not a petitioned action is 
warranted within 12 months after receiving any petition for which we 
have determined contains substantial scientific or commercial 
information indicating that the petitioned action may be warranted 
(``12-month finding''). We must make a finding that the petitioned 
action is: (1) Not warranted; (2) warranted; or (3) warranted but 
precluded. We must publish a notice of these 12-month findings in the 
Federal Register.

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act (16 U.S.C. 1533) and the implementing 
regulations (50 CFR part 424) set forth procedures for adding species 
to, removing species from, or reclassifying species on the Lists of 
Endangered and Threatened Wildlife and Plants (Lists). The Act states 
that the term ``species'' includes any subspecies of fish or wildlife 
or plants, and any distinct population segment of any species of 
vertebrate fish or wildlife which interbreeds when mature (16 U.S.C. 
1532(16)). The Act defines an ``endangered species'' as any species 
that is in danger of extinction throughout all or a significant portion 
of its range (16 U.S.C. 1532(6)), and a ``threatened species'' as any 
species that is likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its range 
(16 U.S.C. 1532(20)). The Act requires that we determine whether any 
species is an endangered species or a threatened species because of any 
of the following factors:

    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.

    These factors represent broad categories of natural or human-caused 
actions or conditions that could have an effect on a species' continued 
existence. In evaluating these actions and conditions, we look for 
those that may have a negative effect on individuals of the species, as 
well as other actions or conditions that may ameliorate any negative 
effects or may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). The term ``threat'' 
may encompass--either together or separately--the source of the action 
or condition or the action or condition itself. However, the mere 
identification of any threat(s) does not necessarily mean that the 
species meets the statutory definition of an ``endangered species'' or 
a ``threatened species.'' In determining whether a species meets either 
definition, we must evaluate all identified threats by considering the 
expected response by the species, and the effects of the threats--in 
light of those actions and conditions that will ameliorate the 
threats--on an individual, population, and species level. We evaluate 
each threat and its expected effects on the species, then analyze the 
cumulative effect of all of the threats on the species as a whole. We 
also consider the cumulative effect of the threats in light of those 
actions and conditions that will have positive effects on the species, 
such as any existing regulatory mechanisms or conservation efforts. The 
Secretary determines whether the species meets the definition of an 
``endangered species'' or a ``threatened species'' only after 
conducting this cumulative analysis and describing the expected effect 
on the species now and in the foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as the 
Service can reasonably determine that both the future threats and the 
species' responses to those threats are likely. In other words, the 
foreseeable future is the period of time in which we can make reliable 
predictions. ``Reliable'' does not mean ``certain''; it means 
sufficient to provide a reasonable degree of confidence in the 
prediction. Thus, a prediction is reliable if it is reasonable to 
depend on it when making decisions.
    It is not always possible or necessary to define foreseeable future 
as a particular number of years. Analysis of the foreseeable future 
uses the best scientific and commercial data available and should 
consider the timeframes applicable to the relevant threats and to the 
species' likely responses to those threats in view of its life-history 
characteristics. Data that are typically relevant to assessing the 
species' biological response include species-specific factors such as 
lifespan, reproductive rates or productivity,

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certain behaviors, and other demographic factors.
    In conducting our evaluation of the five factors provided in 
section 4(a)(1) of the Act to determine whether the Sonoran desert 
tortoise meets the definition of an endangered species or a threatened 
species, we considered and thoroughly evaluated the best scientific and 
commercial information available regarding the past, present, and 
future stressors and threats. We reviewed the petition, information 
available in our files, and other available published and unpublished 
information. Our evaluation may include information from recognized 
experts; Federal, State, and Tribal governments; academic institutions; 
foreign governments; private entities; and other members of the public.
    The species assessment form for the species contains more detailed 
biological information, a thorough analysis of the listing factors, a 
list of literature cited, and an explanation of why we determined that 
the species does not meet the Act's definition of an endangered species 
or a threatened species. A thorough review of the taxonomy, life 
history, ecology, and stressors to the Sonoran desert tortoise is 
presented in the species status assessment report (USFWS 2021, entire). 
This supporting information can be found on the internet at https://www.regulations.gov under Docket No. FWS-R2-ES-2021-0153. The following 
is an informational summary for the finding in this document.

Previous Federal Actions

    On December 30, 1982, the Service published in the Federal Register 
(47 FR 58454) a notice of review that determined the desert tortoise 
(Gopherus agassizii) throughout its range in the United States and 
Mexico to be a Category 2 candidate species. Category 2 candidate 
species were taxa for which the Service had in its possession 
information that indicated that proposing to list the species as 
endangered or threatened was possibly appropriate, but for which 
substantial biological data were not available to support a proposed 
rule. On April 2, 1990, we published in the Federal Register (55 FR 
12178) a final rule designating the Mojave population of the desert 
tortoise (occurring north and west of the Colorado River) as a 
threatened species under the Act. Currently, the Mojave population of 
the desert tortoise is recognized as a distinct population segment 
(DPS) under the Act.
    On October 15, 2008, we received a petition dated October 9, 2008, 
from WildEarth Guardians and Western Watersheds Project (petitioners) 
requesting that the Sonoran population of the desert tortoise be listed 
under the Act as a distinct population segment (DPS) and that the DPS 
be listed as endangered or threatened range-wide (in the United States 
and Mexico). The petitioners also requested that critical habitat be 
designated for the DPS. On August 28, 2009, we published in the Federal 
Register (74 FR 44335) our 90-day finding that the petition presented 
substantial scientific information indicating that listing the Sonoran 
population of the desert tortoise may be warranted. That document also 
initiated a status review of the Sonoran population of the desert 
tortoise.
    On December 14, 2010, we published in the Federal Register (75 FR 
78094) our 12-month finding that listing the Sonoran DPS of the desert 
tortoise was warranted, but precluded by other higher priority actions, 
and the entity was added to our list of candidate species. In 2012, new 
information was assessed that elevated the Sonoran population of the 
desert tortoise to a full species (Gopherus morafkai). We noted this 
taxonomic change in the 2012 candidate notice of review (CNOR) and 
revised its accepted nomenclature to ``Sonoran desert tortoise'' (77 FR 
69994; November 21, 2012). We also reaffirmed its candidate status in 
the CNORs published in 2012 (77 FR 69994; November 21, 2012), 2013 (78 
FR 70104; November 22, 2013), and 2014 (79 FR 72450; December 5, 2014), 
reaffirming that it was warranted for listing but remained precluded by 
higher priority actions. After completing a species status assessment, 
we published in the Federal Register (80 FR 60321; October 6, 2015) a 
12-month petition finding that listing the Sonoran desert tortoise as 
endangered or threatened under the Act was not warranted.
    The petitioners filed a complaint on September 5, 2019, challenging 
our 2015 not-warranted finding for the Sonoran desert tortoise and 
alleging violations of the Act. We reached a settlement agreement with 
the petitioners that was approved by the U.S. District Court on August 
3, 2020, to reconsider our not-warranted finding and to develop a new 
12-month finding as to whether the Sonoran desert tortoise warrants 
listing as an endangered or threatened species under the Act. As a 
result of that agreement, we returned the Sonoran desert tortoise to 
the candidate list (see 85 FR 73164; November 16, 2020). This document 
constitutes our new 12-month finding.

Summary of Finding

    The Sonoran desert tortoise occurs in the Sonoran Desert ecoregion 
of Arizona in the United States and Sonora in Mexico. It is patchily 
distributed across a large range that covers roughly 68,600 square 
miles (177,673 square kilometers). Adapted to arid environments, 
Sonoran desert tortoises spend most of their time in below-ground 
shelter-sites, with emergence timed to resource availability such as 
precipitation or forage. Precipitation, particularly the summer 
monsoons, encourages new vegetative growth that is consumed by Sonoran 
desert tortoises. Typical habitat consists of rocky slopes and incised 
washes that support shelter sites. The amount and distribution of this 
habitat is important to maintain the species' viability.
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the Sonoran desert tortoise, and we evaluated all relevant factors 
under the five listing factors, including any regulatory mechanisms and 
conservation measures addressing these threats. We identified several 
threats that could reduce the viability of the species. Some, such as 
nonnative vegetation and altered wildfire regimes, have the potential 
to affect the Sonoran desert tortoise on localized scales and the best 
available information suggests these threats are unlikely to affect 
long-term viability of the species. Human development can degrade or 
remove Sonoran desert tortoise habitat and contribute to reduced 
survival rates due to human-tortoise interactions and incidental 
mortality. Suitable Sonoran desert tortoise habitat in portions of the 
species' range, particularly in Arizona, has been converted to human 
development. Drought has a measurable effect on the Sonoran desert 
tortoise's survival rates and may become more frequent and severe into 
the future due to climate change. Changes in precipitation and 
temperature patterns may also affect the amount and suitability of 
Sonoran desert tortoise habitat. Several Federal, State, and county 
agencies have been implementing conservation measures through best 
management practices, specific to the Sonoran desert tortoise, to help 
sustain the species and its habitat where possible.
    Currently, we estimate that the Sonoran desert tortoise occupies 
much of its historical range and is abundant in Arizona and Sonora, on 
the order of hundreds of thousands of extant adults. Population 
monitoring data collected for approximately 20 to 30 years on 17 plots

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located on Bureau of Land Management (BLM) land in portions of the 
species' range in Arizona have not indicated substantial declines or 
extirpations. Habitat modeling indicates an estimated 49,222 square 
miles (127,484 square kilometers) of suitable Sonoran desert tortoise 
habitat occurs in Arizona and Sonora, with 24 percent of that 
considered high suitability. In Arizona, 29 percent of the species' 
range is on publicly-owned lands managed specifically for the benefit 
of wildlife, including the Sonoran desert tortoise.
    Upon examining the current trends and a range of future scenarios, 
we expect that human development and climate change will have the 
greatest impact on the Sonoran desert tortoise's viability due to its 
effects on habitat and survival rates. Urban expansion may result in 
the loss of Sonoran desert tortoise habitat, and adult survival rates 
have been shown to decrease in proximity to urban areas. Drought, a 
primary stressor shown to result in population crashes over abbreviated 
time frames, significantly reduces survival rates and may become more 
common and severe with climate change. The amount and distribution of 
habitat may also shift due to changes in precipitation and temperature 
patterns driven by climate change. In our species status assessment 
report, we modeled these effects to project Sonoran desert tortoise 
population trends into the future (USFWS 2021, pp. 59-71).
    Even with the projected effects of urban expansion and climate 
change, ample amounts of habitat capable of supporting Sonoran desert 
tortoises are expected to remain by the end of the century. Although 
declines in survival are anticipated near urban areas, we found these 
effects are not enough to significantly reduce viability of the species 
as a whole, and the affected areas only cover a relatively small 
portion of the species' range (17 percent). Our modeling projects that 
future drought is expected to result in a negative growth rate by the 
end of century and likely declines in overall abundance. The magnitude 
of these declines varies depending on the assumptions of future 
environmental changes. However, our modeling indicates that the risk of 
quasi-extinction by end of century is less than 1 percent regardless of 
the scenario. Due to high current estimated population sizes and a 
large area of suitable habitat, even with the projected declines, we 
anticipate the Sonoran desert tortoise will continue to occupy the 
majority of currently suitable habitat in sufficient numbers such that 
the species maintains viability. After evaluating the best available 
scientific and commercial information on potential threats acting 
individually or in combination, we find that Sonoran desert tortoise 
populations are expected to maintain resiliency, redundancy, and 
representation in the foreseeable future throughout all or a 
significant portion of the species' range.
    Our review of the best available scientific and commercial 
information regarding the past, present, and future threats to the 
species indicates that the Sonoran desert tortoise is not in danger of 
extinction nor likely to become endangered within the foreseeable 
future throughout all or a significant portion of its range and does 
not meet the definition of an endangered species or a threatened 
species under the Act. Therefore, we find that listing the Sonoran 
desert tortoise as an endangered or threatened species under the Act is 
not warranted at this time. A detailed discussion of the basis for this 
finding can be found in the Sonoran desert tortoise species assessment 
form, which outlines in more detail the rationale for our decision, and 
the revised species status assessment report (USFWS 2021, entire), and 
other supporting documents (see ADDRESSES, above), which capture the 
scientific information upon which our decision was based.

New Information

    We request that you submit any new information concerning the 
taxonomy of, biology of, ecology of, status of, or stressors to the 
Sonoran desert tortoise to the person listed above under FOR FURTHER 
INFORMATION CONTACT, whenever it becomes available. New information 
will help us monitor this species and make appropriate decisions about 
its conservation and status. We encourage local agencies and 
stakeholders to continue cooperative monitoring and conservation 
efforts.

References Cited

    A list of the references cited in this document is available on the 
internet at https://www.regulations.gov under Docket No. FWS-R2-ES-
2021-0153 in the species assessment form, or upon request from the 
person listed above under FOR FURTHER INFORMATION CONTACT.

Authors

    The primary authors of this document are the staff members of the 
Species Assessment Team, Ecological Services Program.

Authority

    The authority for this action is section 4 of the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

Martha Williams,
Principal Deputy Director, Exercising the Delegated Authority of the 
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2022-02422 Filed 2-7-22; 8:45 am]
BILLING CODE 4333-15-P