[Federal Register Volume 88, Number 176 (Wednesday, September 13, 2023)]
[Proposed Rules]
[Pages 62725-62747]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-18547]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2023-0073; FF09E21000 FXES1111090FEDR 234]
RIN 1018-BG35


Endangered and Threatened Wildlife and Plants; Endangered Species 
Status for Quitobaquito Tryonia and Designation of Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list the Quitobaquito tryonia (Tryonia quitobaquitae), a springsnail 
species from Arizona, as an endangered species under the Endangered 
Species Act of 1973, as amended (Act). This determination also serves 
as our 12-month finding on a petition to list the Quitobaquito tryonia. 
After a review of the best available scientific and commercial 
information, we find that listing the species is warranted. We also 
propose to designate critical habitat for the Quitobaquito tryonia 
under the Act. In total, approximately 6,095 square feet (566 square 
meters) across 2 subunits in Pima County, Arizona, fall within the 
boundaries of the proposed critical habitat designation. We also 
announce the availability of a draft economic analysis (DEA) of the 
proposed designation of critical habitat for Quitobaquito tryonia. If 
we finalize this rule as proposed, it would extend the Act's 
protections to this species and its designated critical habitat.

DATES: We will accept comments received or postmarked on or before 
November 13, 2023. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES below) must be received by 11:59 p.m. 
eastern time on the closing date. We must receive requests for a public 
hearing, in writing, at the address shown in FOR FURTHER INFORMATION 
CONTACT by October 30, 2023.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R2-ES-2023-0073, 
which is the docket number for this rulemaking. Then, click on the 
Search button. On the resulting page, in the panel on the left side of 
the screen, under the Document Type heading, check the Proposed Rule 
box to locate this document. You may submit a comment by clicking on 
``Comment.''
    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R2-ES-2023-0073, U.S. Fish and Wildlife Service, 
MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
    We request that you send comments only by the methods described 
above. We will post all comments on https://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see Information Requested, below, for more information).
    Availability of supporting materials: Supporting materials, such as 
the species status assessment report, are available on the Service's 
website at https://www.fws.gov/office/arizona-ecological-services, at 
https://www.regulations.gov at Docket No. FWS-R2-ES-2023-0073, or both. 
For the proposed critical habitat designation, the coordinates or plot 
points or both from which the map is generated are included in the 
decision file for this critical habitat designation and are available 
at https://www.regulations.gov at Docket No. FWS-R2-ES-2023-0073 and on 
the Service's website at https://www.fws.gov/office/arizona-ecological-services.

FOR FURTHER INFORMATION CONTACT: Heather Whitlaw, Field Supervisor, 
U.S. Fish and Wildlife Service, Arizona Ecological Services Field 
Office, 9828 North 31st Ave #C3, Phoenix, AZ 85051-2517; telephone 602-
242-0210. Individuals in the United States who are deaf, deafblind, 
hard of hearing, or have a speech disability may dial 711 (TTY, TDD, or 
TeleBraille) to access telecommunications relay services. Individuals 
outside the United States should use the relay services offered within 
their country to make international calls to the point-of-contact in 
the United States.

SUPPLEMENTARY INFORMATION: 

Executive Summary

    Why we need to publish a rule. Under the Act, a species warrants 
listing if it meets the definition of an endangered species (in danger 
of extinction throughout all or a significant portion of its range) or 
a threatened species (likely to become an endangered species within the 
foreseeable future throughout all or a significant portion of its 
range). If we determine that a species warrants listing, we must list 
the species promptly and designate the species' critical habitat to the 
maximum extent prudent and determinable. We have determined that the 
Quitobaquito tryonia meets the definition of an endangered species; 
therefore, we are proposing to list it as such and proposing a 
designation of its critical habitat. Both listing a species as an 
endangered or threatened species and making a critical habitat 
determination 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. We propose to list the Quitobaquito 
tryonia as an endangered species under the Act, and we propose the 
designation of critical habitat for the species.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species because of any of five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that Quitobaquito tryonia is 
endangered due to the following threats: decline in spring flow 
resulting from groundwater pumping and ongoing drought; effects of 
climate change; and spring modification.
    Section 4(a)(3) of the Act requires the Secretary of the Interior 
(Secretary), to the maximum extent prudent and determinable, to 
designate critical habitat concurrent with listing. Section 3(5)(A) of 
the Act defines critical habitat as (i) the specific areas within the 
geographical area occupied by the species, at the time it is listed, on 
which are found those physical or biological features (I) essential to 
the conservation of the species and (II) which may require special 
management considerations or protection; and (ii) specific areas 
outside the geographical area occupied by the species at the time it is 
listed, upon a determination by the Secretary that such areas are 
essential for the conservation of the species. Section 4(b)(2) of the 
Act states that the Secretary must make the designation on the basis of 
the best scientific data available and after taking into consideration 
the economic impact, the impact on national security, and any

[[Page 62726]]

other relevant impacts of specifying any particular area as critical 
habitat.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other governmental agencies, Native 
American Tribes, the scientific community, industry, or any other 
interested parties concerning this proposed rule. We particularly seek 
comments concerning:
    (1) The species' biology, range, and population trends, including:
    (a) Biological or ecological requirements of the species, including 
habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns 
and the locations of any additional populations of this species;
    (d) Historical and current population levels, and current and 
projected trends; and
    (e) Past and ongoing conservation measures for the species, its 
habitat, or both.
    (2) Threats and conservation actions affecting the species, 
including:
    (a) Factors that may be affecting the continued existence of the 
species, which may include habitat modification or destruction, 
overutilization, disease, predation, the inadequacy of existing 
regulatory mechanisms, or other natural or manmade factors;
    (b) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this species; and
    (c) Existing regulations or conservation actions that may be 
addressing threats to this species.
    (3) Additional information concerning the historical and current 
status of this species.
    (4) Specific information on:
    (a) The amount and distribution of Quitobaquito tryonia habitat;
    (b) Any additional areas occurring within the range of the species 
that should be included in the designation because they (i) are 
occupied at the time of listing and contain the physical or biological 
features that are essential to the conservation of the species and that 
may require special management considerations or protection, or (ii) 
are unoccupied at the time of listing and are essential for the 
conservation of the species;
    (c) Special management considerations or protection that may be 
needed in critical habitat areas we are proposing, including managing 
for the potential effects of climate change; and
    (d) Whether occupied areas are adequate for the conservation of the 
species, as this will help us evaluate the potential to include areas 
not occupied at the time of listing. Additionally, please provide 
specific information regarding whether or not unoccupied areas would, 
with reasonable certainty, contribute to the conservation of the 
species and contain at least one physical or biological feature 
essential to the conservation of the species. We also seek comments or 
information regarding whether areas not occupied at the time of listing 
qualify as habitat for the species.
    (5) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (6) Any probable economic, national security, or other relevant 
impacts of designating any area that may be included in the final 
designation, and the related benefits of including or excluding 
specific areas.
    (7) Information on the extent to which the description of probable 
economic impacts in the draft economic analysis is a reasonable 
estimate of the likely economic impacts.
    (8) Whether any specific areas we are proposing for critical 
habitat designation should be considered for exclusion under section 
4(b)(2) of the Act (16 U.S.C. 1531 et seq.), and whether the benefits 
of potentially excluding any specific area outweigh the benefits of 
including that area under section 4(b)(2) of the Act. If you think we 
should exclude any areas, please provide information supporting a 
benefit of exclusion.
    (9) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for, or 
opposition to, the action under consideration without providing 
supporting information, although noted, do not provide substantial 
information necessary to support a determination. Section 4(b)(1)(A) of 
the Act directs that determinations as to whether any species is an 
endangered or a threatened species must be made solely on the basis of 
the best scientific and commercial data available, and section 4(b)(2) 
of the Act directs that the Secretary shall designate critical habitat 
on the basis of the best scientific data available.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in ADDRESSES.
    If you submit information via https://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the website. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on https://www.regulations.gov.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov.
    Our final determination may differ from this proposal because we 
will consider all comments we receive during the comment period as well 
as any information that may become available after this proposal. Based 
on the new information we receive (and, if relevant, any comments on 
that new information), we may conclude that the species is threatened 
instead of endangered, or we may conclude that the species does not 
warrant listing as either an endangered species or a threatened 
species. For critical habitat, our final designation may not include 
all areas proposed, may include some additional areas that meet the 
definition of critical habitat, or may exclude some areas if we find 
the benefits of exclusion outweigh the benefits of inclusion and 
exclusion will not result in the extinction of the species. In our 
final rule, we will clearly explain our rationale and the basis for our 
final decision, including why we made changes, if any, that differ from 
this proposal.

Public Hearing

    Section 4(b)(5) of the Act provides for a public hearing on this 
proposal, if requested. Requests must be received by the date specified 
in DATES. Such requests must be sent to the address shown in FOR 
FURTHER INFORMATION CONTACT. We will schedule a public hearing on this 
proposal, if requested, and announce the date, time, and place of the 
hearing, as well as how to obtain

[[Page 62727]]

reasonable accommodations, in the Federal Register and local newspapers 
at least 15 days before the hearing. We may hold the public hearing in 
person or virtually via webinar. We will announce any public hearing on 
our website, in addition to the Federal Register. The use of virtual 
public hearings is consistent with our regulations at 50 CFR 
424.16(c)(3).

Previous Federal Actions

    On June 25, 2007, we received a petition dated June 18, 2007, from 
Forest Guardians (now WildEarth Guardians) to list 475 species, 
including the Quitobaquito tryonia, in the southwestern United States 
as endangered or threatened species and to designate critical habitat 
under the Act. On December 16, 2009, we published a partial 90-day 
finding (74 FR 66866) on 192 species from that petition; in that 
document, we announced that the petition presented substantial 
information that the Quitobaquito tryonia may be warranted for listing.

Peer Review

    A species status assessment (SSA) team prepared an SSA report for 
the Quitobaquito tryonia. The SSA team was composed of Service 
biologists, in consultation with other species experts. The SSA report 
represents a compilation of the best scientific and commercial data 
available concerning the status of the species, including the impacts 
of past, present, and future factors (both negative and beneficial) 
affecting the species.
    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 
2016, memorandum updating and clarifying the role of peer review of 
listing actions under the Act, we solicited independent scientific 
review of the information contained in the Quitobaquito tryonia SSA 
report. We sent the SSA report to four independent peer reviewers and 
received two responses. We also sent the SSA report to six partner 
reviewers and received three responses. Results of this structured peer 
review process can be found at https://www.regulations.gov. In 
preparing this proposed rule, we incorporated the results of these 
reviews, as appropriate, into the SSA report, which is the foundation 
for this proposed rule.

Summary of Peer Reviewer Comments

    As discussed in Peer Review above, we received comments from two 
peer reviewers on the draft SSA report. We reviewed all comments we 
received from the peer reviewers for substantive issues and new 
information regarding the information contained in the SSA report. The 
peer reviewers generally concurred with our methods and conclusions, 
and provided additional information, clarifications, and suggestions 
that we incorporated into an updated version of the SSA report. One 
reviewer requested that we analyze water quality quantitatively in the 
report. We clarified that although some water quality parameters have 
been recorded in the springs that the Quitobaquito tryonia inhabits, we 
do not know the full suite of parameters, nor the thresholds to which 
the species is sensitive. Otherwise, no substantive changes to our 
analysis and conclusions within the SSA report were deemed necessary, 
and peer reviewer comments are addressed in version 1.1 of the SSA 
report (Service 2022, entire).

I. Proposed Listing Determination

Background

    The Quitobaquito tryonia is a small freshwater snail with a conical 
shell that measures 0.05 to 0.08 inches (in) (1.4 to 2.1 millimeters 
(mm)) in length. The shell has 3.5 to 4.5 highly convex whorls with 
deep sutures (or indentations where whorls meet) and is typically 
clear, gray, or black in color. Quitobaquito tryonia is dioecious 
(Hershler 2001, pp. 3-5), meaning male and female organs occur in 
separate individuals. The lifespan of springsnails is thought to be 
annual (Lysne et al. 2007, p. 649; Brown et al. 2008, p. 487), with 
estimates of longevity ranging from 9 to 15 months (Pennak 1989, p. 
552).
    Quitobaquito tryonia is likely an herbivore or detritivore that 
primarily grazes on periphyton (a mixture of algae, bacteria, detritus, 
fungi, diatoms, and protozoa that grow on exposed surfaces (Lysne et 
al. 2007, p. 649)) and aquatic plants (Pyron and Brown 2015, pp. 386, 
401). The species can more easily consume periphyton, which is also 
more nutrient-rich than aquatic plants; however, if periphyton 
availability is limited or depleted, Quitobaquito tryonia will consume 
aquatic plants (Pyron and Brown 2015, p. 399).
    Historically, Quitobaquito tryonia is known from three proximal 
springs or spring complexes, Quitobaquito Springs, Williams Spring, and 
Burro Spring, that lie near the international border of the United 
States (Arizona) and Mexico; these springs/spring complexes are in the 
southwestern corner of Organ Pipe Cactus National Monument, which is 
managed by the National Park Service (NPS), in Pima County, Arizona 
(Hershler and Landye 1988, p. 50). Quitobaquito tryonia was first 
collected in 1963, from Quitobaquito Springs (Hershler and Landye 1988, 
p. 50; Rosen et al. 2010, p. 8). The species has been extirpated from 
Williams and Burro Springs but remains extant at Quitobaquito Springs. 
The species is found in the 200-meter (m) (700-foot (ft)) spring 
channel of Quitobaquito Springs, which is a human-made, concrete-lined 
channel with riffle, run, and pool habitat types that was built as part 
of a restoration project in 1989. The channel is fed by two springs, 
the Northeast and Southwest springs. The NPS regularly manages 
vegetation along the stream channel to reduce submerged and emergent 
vegetation, creating a mosaic of available habitats and ensuring water 
can flow freely through the channel.
    The Quitobaquito tryonia was recently detected at a fourth location 
in October 2020, a seep (Hillside Seep #2) located approximately 100 m 
(328 ft) southeast of the main channel at Quitobaquito Springs. 
Hillside Seep #2 is located to the southeast and slightly upslope from 
the Southwest Spring at Quitobaquito. The seep is not hydrologically 
connected overland to the concrete-lined spring channel at Quitobaquito 
Springs and, for the purposes of this analysis, is being considered a 
separate population. While there are no surface water connections 
between the seep and spring channel, it is likely that they have the 
same groundwater source based on proximity and local geology. 
Quitobaquito tryonia is the only species in the Cochliopidae family of 
small freshwater snails that occurs in the spring complex. There are 
six additional seeps (including Hillside Seep #1) that have been 
surveyed in the area near Quitobaquito Springs that have low flow and 
possible springsnail habitat, but no Quitobaquito tryonia were found 
(Sorensen 2021, p. 10). The presence of dense vegetation precluded 
searching all possible habitat, so it is possible that Quitobaquito 
tryonia individuals are present in the inaccessible portions of these 
seeps. Based on the hydrology and geology of the area, additional 
undocumented seeps may exist in the area of Quitobaquito Springs that 
have not been investigated for presence of Quitobaquito tryonia.
    Tohono O'odham and Hia Ced O'odham farmers inhabited the area 
including the Quitobaquito Springs complex for several centuries prior 
to the arrival of Europeans in the 1600s, and the spring water was used 
for irrigation (Bennett and Kunzmann 1989, p. 1; Nabhan et al. 1982, 
pp. 124-126). Large-scale water management of the

[[Page 62728]]

springs likely began in 1863, when Euro-American settlers excavated 
Quitobaquito Pond and built a dam to hold water diverted from the two 
main spring sources (Bennett and Kunzmann 1989, p. 15; Pearson and 
Conner 2000, p. 392). Irrigation ditches were constructed from the pond 
for agricultural fields to the south and west. In 1915-1919, grazing 
pressure intensified with the establishment of a large cattle operation 
and ranch that encompassed all of present-day Organ Pipe Cactus 
National Monument (Bennett and Kunzmann 1989, pp. 21-22).
    The Quitobaquito tryonia requires perennial spring flow, adequate 
water quality, and substrates or aquatic vegetation of sufficient type 
and quantity. Brooded young, juveniles, and adults all need adequate 
spring flow and water quality to meet their resource functions, which 
include feeding, growth, survival, and breeding (Hershler 1984, p. 68; 
Hershler and Sada 2002, p. 256; Martinez and Thome 2006, p. 14). 
Specifically, spring flow must be perennial to prevent desiccation 
(drying out) of individuals and to maintain stable water quality 
parameters. The Quitobaquito tryonia also needs suitable substrate and 
aquatic vegetation for shelter and periphyton growth. While Tryonia 
spp. are found on a variety of substrate types, there is some evidence 
that coarse substrates may promote higher abundances of Quitobaquito 
tryonia (Bogan 2018, entire; Williams and Sorensen 2019, p. 2).
    For a thorough review of the taxonomy, life history, and ecology of 
the Quitobaquito tryonia, please refer to the SSA report (Service 2022, 
pp. 4-7).

Regulatory and Analytical Framework

Regulatory Framework

    Section 4 of the Act (16 U.S.C. 1533) and the implementing 
regulations in title 50 of the Code of Federal Regulations set forth 
the procedures for determining whether a species is an endangered 
species or a threatened species, issuing protective regulations for 
threatened species, and designating critical habitat for endangered and 
threatened species. In 2019, jointly with the National Marine Fisheries 
Service, the Service issued a final rule that revised the regulations 
in 50 CFR part 424 regarding how we add, remove, and reclassify 
endangered and threatened species and the criteria for designating 
listed species' critical habitat (84 FR 45020; August 27, 2019). On the 
same day, the Service also issued final regulations that, for species 
listed as threatened species after September 26, 2019, eliminated the 
Service's general protective regulations automatically applying to 
threatened species the prohibitions that section 9 of the Act applies 
to endangered species (84 FR 44753; August 27, 2019).
    The Act defines an ``endangered species'' as a species that is in 
danger of extinction throughout all or a significant portion of its 
range, and a ``threatened species'' as a species that is likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether any species is an endangered species or a threatened 
species because of any of the following factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    These factors represent broad categories of natural or human-caused 
actions or conditions that could have an effect on a species' continued 
existence. In evaluating these actions and conditions, we look for 
those that may have a negative effect on individuals of the species, as 
well as other actions or conditions that may ameliorate any negative 
effects or may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). The term ``threat'' 
may encompass--either together or separately--the source of the action 
or condition or the action or condition itself.
    However, the mere identification of any threat(s) does not 
necessarily mean that the species meets the statutory definition of an 
``endangered species'' or a ``threatened species.'' In determining 
whether a species meets either definition, we must evaluate all 
identified threats by considering the species' expected response and 
the effects of the threats--in light of those actions and conditions 
that will ameliorate the threats--on an individual, population, and 
species level. We evaluate each threat and its expected effects on the 
species, then analyze the cumulative effect of all of the threats on 
the species as a whole. We also consider the cumulative effect of the 
threats in light of those actions and conditions that will have 
positive effects on the species, such as any existing regulatory 
mechanisms or conservation efforts. The Secretary determines whether 
the species meets the definition of an ``endangered species'' or a 
``threatened species'' only after conducting this cumulative analysis 
and describing the expected effect on the species now and in the 
foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as we can 
reasonably determine that both the future threats and the species' 
responses to those threats are likely. In other words, the foreseeable 
future is the period of time in which we can make reliable predictions. 
``Reliable'' does not mean ``certain''; it means sufficient to provide 
a reasonable degree of confidence in the prediction. Thus, a prediction 
is reliable if it is reasonable to depend on it when making decisions.
    It is not always possible or necessary to define the foreseeable 
future as a particular number of years. Analysis of the foreseeable 
future uses the best scientific and commercial data available and 
should consider the timeframes applicable to the relevant threats and 
to the species' likely responses to those threats in view of its life-
history characteristics. Data that are typically relevant to assessing 
the species' biological response include species-specific factors such 
as lifespan, reproductive rates or productivity, certain behaviors, and 
other demographic factors.

Analytical Framework

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

[[Page 62729]]

    To assess Quitobaquito tryonia viability, we used the three 
conservation biology principles of resiliency, redundancy, and 
representation (Shaffer and Stein 2000, pp. 306-310). Briefly, 
resiliency is the ability of the species to withstand environmental and 
demographic stochasticity (for example, wet or dry, warm or cold 
years), redundancy is the ability of the species to withstand 
catastrophic events (for example, droughts, large pollution events), 
and representation is the ability of the species to adapt to both near-
term and long-term changes in its physical and biological environment 
(for example, climate conditions, pathogens). In general, species 
viability will increase with increases in resiliency, redundancy, and 
representation (Smith et al. 2018, p. 306). Using these principles, we 
identified the species' ecological requirements for survival and 
reproduction at the individual, population, and species levels, and 
described the beneficial and risk factors influencing the species' 
viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the 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. We use this information to inform our regulatory 
decision.
    The following is a summary of the key results and conclusions from 
the SSA report; the full SSA report can be found at Docket No. FWS-R2-
ES-2023-0073 on https://www.regulations.gov and at https://www.fws.gov/office/arizona-ecological-services.

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
species and its resources, and the threats that influence the species' 
current and future condition, in order to assess the species' overall 
viability and the risks to that viability. For the Quitobaquito tryonia 
to maintain viability, its populations must be highly resilient with 
sufficient redundancy and representation. Several factors influence the 
resiliency of the Quitobaquito tryonia populations, including: (1) the 
reduction of spring discharge, (2) effects of climate change, (3) 
spring modification, and (4) conservation actions. These resiliency 
factors and habitat elements are discussed in detail in the SSA report 
(Service 2022, entire) and are summarized here.

Species Needs

Spring Flow
    Spring flow in spring systems is maintained by groundwater, and 
individual springs may range widely in size, water chemistry, 
morphology, landscape setting, and persistence (Springer and Stevens 
2009, p. 84). Groundwater recharge of aquifers occurs through 
precipitation, through surface water from rivers, or as an 
anthropogenic input from irrigation and municipal returns (Tr[ccaron]ek 
and Zojer 2010, p. 87). A decline in groundwater recharge or increase 
in groundwater discharge (e.g., from groundwater withdrawal, drought, 
or increased evapotranspiration) can lead to reductions, disruptions, 
or cessation of spring flow. While the Quitobaquito tryonia possesses 
an operculum (Johnson et al. 2013, p. 248), which enables the shell to 
be sealed, this only provides protection from drying for a very limited 
period of time (i.e., hours to days).
Water Quality
    While the full suite of water quality conditions that the 
Quitobaquito tryonia prefers has not been determined, water quality 
measurements have been recorded for some parameters in springs 
inhabited by the Quitobaquito tryonia or other closely related species. 
The water chemistry of a spring is strongly influenced by aquifer 
geology. Several habitat variables, such as dissolved oxygen, pH, 
conductivity, and temperature, may influence the distribution and 
abundance of springsnails (O'Brien and Blinn 1999, pp. 231-232; 
Mladenka and Minshall 2001, pp. 209-211; Malcom et al. 2005, p. 75; 
Martinez and Thome 2006, pp. 12-15; Lysne et al. 2007, p. 650). No 
known sources of contaminants are present in the Quitobaquito Springs 
system, although some concern has been raised regarding the aerial 
application of agricultural pesticides in the Rio Sonoyta watershed of 
Mexico and the threat of wind drift (NPS 2006a, p. 1). However, a 
contaminant study from the early 1990s found no evidence of 
contamination from sediment samples taken from Quitobaquito Pond (King 
et al. 1996, pp. 3-5).
Substrate and Vegetation
    While Tryonia spp. are found on a variety of substrate types, there 
is some evidence that coarse substrates may promote higher abundances 
of Quitobaquito tryonia. Bogan (2018, entire) noted differences in 
densities of Quitobaquito tryonia within the 200-m (700-ft) spring 
channel at Quitobaquito Springs. The spring channel at Quitobaquito 
Springs is a concrete-lined channel with riffle, run, and pool habitat 
types. The NPS regularly manages vegetation along the stream channel to 
reduce submerged and emergent vegetation, creating a mosaic of 
available habitats and ensuring water can flow freely through the 
channel. Within the channel, Quitobaquito tryonia were densest in 
gravel riffles, followed by concrete runs and riffles, then vegetated 
pools. However, surveys by Arizona Game and Fish Department (AZGFD) 
biologists at Quitobaquito Springs have not found any Quitobaquito 
tryonia along the densely vegetated margins of the pond, located at the 
terminus of the spring channel (Williams and Sorensen 2019, p. 2).
    Organ Pipe Cactus National Monument was established in 1937, but 
cattle operations near Quitobaquito, Williams, and Burro Springs 
continued until large-scale cattle operations ended in 1976 (Warren and 
Anderson 1987, p. 1). In 1978, the remaining cattle were removed from 
the Monument (Bennett and Kunzmann 1989, pp. 15, 21-22). After the 
large-scale cattle operations ended, spring sources became dense with 
vegetation and standing water was reduced (Warren and Anderson 1987, p. 
13). These effects of intensive livestock grazing on vegetation change 
and soil disturbance ended in 1978-79 across the Springs at Organ Pipe 
Cactus National Monument. Occasionally, trespass cattle and other 
livestock (i.e., horses and burros) still occur within the greater 
Organ Pipe Cactus National Monument, but they are not common near 
Quitobaquito Springs. The concrete channel that was installed in 1989 
(NPS 1992, pp. 28-30) also created a more stable system within the 
Springs, so the Quitobaquito tryonia population experiences less of an 
effect of vegetation change, soil disturbance, and reductions/
fluctuations in preferred substrates.

Risk Factors for the Quitobaquito Tryonia

    We reviewed the potential risk factors (i.e., threats, stressors) 
that could be currently affecting the Quitobaquito tryonia. In this 
proposed rule, we will discuss only those factors in detail that

[[Page 62730]]

could meaningfully impact the status of the species. Those risk factors 
that are unlikely to have significant effects on the Quitobaquito 
tryonia, such as vegetation and soil disturbance, invasive species, and 
predation, are not discussed here but are evaluated in the SSA report. 
For example, the introduction of nonnative or invasive predators has 
the potential to negatively affect the Quitobaquito tryonia (Hershler 
1998, p. 14; Sada 2017, p. 11). However, nonnative predators such as 
bullfrogs, crayfish, and cichlids are not currently present in areas 
occupied by the Quitobaquito tryonia. Quitobaquito Springs is a remote, 
isolated natural water, and is neither a destination for anglers (e.g., 
bait bucket dump), nor is stocked with fish from State or Federal 
hatcheries. The primary risk factors (i.e., threats) affecting the 
status of the Quitobaquito tryonia are the reduction of spring 
discharge (Factor A), effects of climate change (Factor E), and spring 
modification (Factor A).
Reduction of Spring Discharge
    Quitobaquito Springs complex is likely supplied by prehistoric 
water (i.e., water that was deposited many millennia before current 
day) stored beneath an area centered around Aguajita Wash with the 
Quitobaquito Hills roughly delineating the western boundary, shallow 
bedrock to the east, and Rio Sonoyta to the south (Carruth 1996, pp. 
18, 20; see figure 4.2 in the SSA report for a map of the area). 
Groundwater recharge in the approximately 100-square-mile area is 
primarily from the limited infiltration (5-10 percent) of local 
rainfall (6.6 inches/year; Carruth 1996, p. 18). The historically 
consistent spring flows at Quitobaquito Springs were highly dependent 
on large, stored water volumes (Carruth 1996, p. 21). However, long-
term spring flow has declined over the last 25 years (see figure 1, 
below; Zamora 2018, p. 146; Zamora et al. 2020, pp. 5-6). Although it 
is uncertain how impacts to the regional aquifer may affect 
Quitobaquito Springs complex outputs (Carruth 1996, p. 21; Zamora et 
al. 2020, p. 15), stressors on the Rio Sonoyta aquifer may include 
municipal water usage for the city of Sonoyta (Sonora, Mexico); local 
agriculture (i.e., irrigated crop fields and cattle ranching); and 
water usage associated with local construction of the U.S.-Mexico 
border wall.
    The City of Sonoyta has grown in human population since the late 
1960s (Brown 1991, p. 6). By 1988, there were 212 wells (165 for 
irrigation) pumping in or near the city of Sonoyta (Brown 1991, p. 18). 
Even with the Mexican government placing a moratorium on any new wells 
being dug in 1988, groundwater withdrawals are exceeding recharge to 
the aquifer (Brown 1991, p. 47). Under conditions in the early 1990s, 
annual pumping capacity was approximately 2.5 times greater than the 
annual rate of recharge (Brown 1991, p. 27), and the number of 
irrigated acres has remained constant since 1982 (Brown 1991, p. 47). 
Census data from 1995 to present day show a peak population for Sonoyta 
and the surrounding area in 2010 with steady declines since. While the 
existing pumping infrastructure is capable of greatly exceeding the 
recharge rate in the Rio Sonoyta basin, during a study from 2001 to 
2006, it was observed that many of the irrigation wells, pumps, and 
ditches were not in use (Rosen et al. 2010, p. 13).
    Additionally, beginning in 2020, there has been water withdrawal 
associated with border wall construction between the United States and 
Mexico; this water withdrawal affected the groundwater and aquifer 
systems supplying Quitobaquito Springs. A permit filed by U.S. Customs 
and Border Protection requested 84,000 gallons per day for a 45-day 
build period. Two new wells were drilled to meet the water demand, 
which may hasten the ``drawdown'' of water resources in an area where 
groundwater withdrawals from the nearby Rio Sonoyta alluvial aquifer 
exceed the recharge rate (Brown 1991, p. 27). These new wells were 
located 11 to 13 kilometers (7 to 8 miles) from Quitobaquito Springs to 
minimize any potential stress on spring output (Morawe 2021, pers. 
comm.). Future border wall construction has been paused, but 
construction, and thus water withdrawal, may resume in the future.
    Drought has the potential to impact spring flow by reducing the 
amount of recharge into the groundwater system and increasing 
evaporation of surface water due to extended periods of high ambient 
temperatures. Statewide trends in Arizona over the last 100 years show 
60 percent of the last 20 years were in drought conditions (NOAA 2021, 
unpaginated). Pima County, Arizona, has been in an extended drought 
since 2000, which coincides with continued declines in spring flow 
output at Quitobaquito Springs. Along with drought, a trend of warmer 
and drier conditions in Organ Pipe Cactus National Monument has been 
observed (NPS 2014, entire). Climate change is expected to further 
exacerbate drought conditions.
    As a result of groundwater withdrawals and drought, spring 
discharge has declined at Quitobaquito, Williams, and Burro Springs. 
Monitoring of spring discharge at Quitobaquito Springs began in 1973 
and has continued intermittently through the present day. Methods for 
measuring discharge varied over the years, but long-term spring flow 
measurements show a decline in discharge over the last 25 years (see 
figure 1, below; Zamora 2018, p. 146; Zamora et al. 2020, pp. 5-6). By 
the early 2000s, Williams and Burro Springs had ceased flowing 
completely (NPS 2006b, p. 9), and the species is now considered 
extirpated from these areas, though there is some evidence of 
seasonally intermittent surface water occurring at Williams Spring 
(Williams and Sorensen 2019, p. 3). Burro Spring became intermittent 
sometime prior to 1992 (NPS 1992, p. 28), while Williams Spring still 
maintained perennial discharge during the summer of 1991 (Goodman 1992, 
p. 143).

[[Page 62731]]

[GRAPHIC] [TIFF OMITTED] TP13SE23.001

Effects of Climate Change
    There is a broad consensus among climate models that arid 
ecosystems are especially vulnerable to the impacts of climate change 
(Seager et al. 2007, pp. 1181-1184; Weiss and Overpeck 2005, p. 2075; 
Archer and Predick 2008, p. 24). The current prognosis of climate 
change impacts on the Sonoran Desert includes fewer frost days; warmer 
temperatures; greater water demand by plants, animals, and people; and 
an increased frequency of extreme weather events (such as heat waves, 
droughts, and floods) (Weiss and Overpeck 2005, p. 2074; Archer and 
Predick 2008, p. 24). For the southwestern United States, the following 
influences of climate change are projected: (1) Continued warming with 
longer and hotter heat waves in summer; (2) decreased average 
precipitation in the southern portion; (3) more frequent and intense 
extreme precipitation in winter; (4) decreased late-season snowpack; 
(5) decreased river flow and soil moisture; (6) more frequent and 
intense flooding in some seasons and some parts of the Southwest, and 
less frequent and intense in other seasons; and (7) hotter, more 
severe, and more frequent droughts in parts of the Southwest (Garfin et 
al. 2013, pp. 5-6).
    Reductions in annual rainfall associated with climate change, 
coupled with hotter temperatures that are projected with very high 
confidence, will likely bring reductions in aquifer inputs due to 
reduced recharge and higher evaporation rates, and will likely have 
negative effects on aquifers across the Southwest. Virtually every 
plausible future climate scenario projects longer dry spells between 
rains, which can have more severe impacts on the landscape, especially 
in spring and summer (Lenart 2007, entire). It is therefore possible 
that some existing Quitobaquito tryonia habitat will periodically dry 
up in the spring and summer during the current century. Bigger and more 
frequent floods caused by more intense, heavy rainfall events are also 
expected episodically in the winter (Overpeck et al. 2013, p. 6) and 
may be even more destructive as riparian vegetation declines within the 
greater system, although flooding may not have as pronounced of an 
effect on the concrete-lined channel of Quitobaquito Springs. Climate 
change trends are highly likely to continue (Overpeck et al. 2013, 
entire). Climatic impacts on the Quitobaquito tryonia will likely be 
further complicated by interactions with other factors (e.g., 
interactions with nonnative species and other habitat-disturbing 
activities).
Spring Modification
    Spring modifications include channel modification, surface water 
diversions, and impoundment at springs. Spring modifications may occur 
for development, management, or restoration purposes and have been 
extensively documented at Quitobaquito Springs, although some 
modification also occurred at Williams Spring. These modifications may 
be either beneficial or detrimental to springsnail populations 
depending on the context. Human alterations of springheads to 
concentrate or divert discharge negatively affect spring systems and 
have resulted in the decline or loss of springsnail populations 
throughout the southwestern United States and northern Mexico (Unmack 
and Minckley 2008, p. 20; Hershler et al. 2011, p. 12; Hershler et al. 
2014, pp. 51, 53, 56, 58-63). Surface water diversions are sources of 
multiple stresses to springs, including altering physical integrity, 
creating conditions that favor nonnative aquatic species, and degrading 
habitat conditions for native riparian vegetation (Sada 2017, pp. 10-
11). Additionally, the presence of pipes, dikes, dams, impoundments, 
channel modifications and dredging, or spring boxes indicate further 
stress in the form of spring diversions and loss of occupancy of 
springsnails at some sites. Although surface water diversions can cause 
stress to springs and springsnails, populations of springsnails in 
historically disturbed habitats can recover if the disturbance is low 
in magnitude and infrequent (Sada 2017, p. 22).
    While restoration may be a temporary source of stress to a spring 
system and springsnails, there is often an overall benefit to 
springsnails by improving all of the species' needs within a spring 
(e.g., water quality, substrate and vegetation, and spring flow). 
Aquatic habitat at Quitobaquito Springs was severely reduced in the 
1970s when

[[Page 62732]]

flow from the Southwest Spring was directed into an underground pipe. 
However, a restoration project in 1989 restored aboveground flow 
through channel modification and the creation of a concrete-lined 
stream that mimics riffle, run, and pool habitats; that stream is 
currently inhabited by the Quitobaquito tryonia.
Summary
    Several historical and ongoing influences, including reductions in 
spring discharge, effects of climate change, and spring modification, 
may affect the viability of the Quitobaquito tryonia. The most 
pervasive threat to the species is the historical and ongoing loss or 
decline in spring discharge. Quitobaquito tryonia populations in two 
springs (Burro and Williams) are now extirpated because of a loss of 
perennial flow, while Quitobaquito Springs has seen a documented 
decline in discharge. The causes of the decline in spring discharge are 
not definitive but are likely related to ongoing drought conditions and 
groundwater pumping. Climate change is expected to exacerbate these 
conditions. Spring modification has had both positive and negative 
influences on the viability of the Quitobaquito tryonia. Historical 
anthropogenic modification of Quitobaquito Springs severely curtailed 
available habitat, while ongoing conservation efforts have restored 
spring channel habitat.

Species Condition

    The current condition of the Quitobaquito tryonia considers the 
risks to the populations that are currently occurring. In the SSA 
report, for each population, we developed and assigned condition 
categories for one demographic factor and three habitat factors that 
are important for the viability of the Quitobaquito tryonia. We used 
abundance to measure demographics of the populations, and we 
characterized habitat using spring flow, water quality, and substrate 
and vegetation as our metrics. The condition scores for each factor 
were then used to determine an overall condition of each population: 
high, moderate, low, or extirpated.
    The Quitobaquito Springs population is in high condition for all 
metrics, with an overall high population resiliency. Hillside Seep #2 
is in low condition for abundance, moderate condition for spring flow 
and substrate and vegetation, and high condition for water quality, for 
an overall moderate population resiliency (see table 1, below). 
Williams Spring and Burro Spring are extirpated.

                                                 Table 1--Current Condition of the Quitobaquito Tryonia
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Demographic metric                               Habitat metric
                                    ----------------------------------------------------------------------------------------------   Current population
             Population                                                                                         Substrate and            resiliency
                                            Abundance              Spring flow           Water quality            vegetation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Quitobaquito Springs...............  High..................  High..................  High.................  High.................  High.
Hillside Seep #2...................  Low...................  Moderate..............  High.................  Moderate.............  Moderate.
Williams Spring....................  Extirpated............  Extirpated............  Extirpated...........  Extirpated...........  Extirpated.
Burro Spring.......................  Extirpated............  Extirpated............  Extirpated...........  Extirpated...........  Extirpated.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Repopulation of extirpated locations (Williams Spring and Burro 
Spring) is unlikely because although the springs may be intermittent, 
perennial surface water is absent, making habitat unsuitable for the 
Quitobaquito tryonia (Williams and Sorensen 2019, p. 3). The exact date 
when the Quitobaquito tryonia became extirpated from these locations is 
unknown, but habitat was deemed unsuitable for springsnails in 2004, 
and no Quitobaquito tryonia were found at this time or during 
subsequent visits (Martinez and Sorensen 2016, p. 4; Williams and 
Sorensen 2019, p. 3).
    Redundancy for the Quitobaquito tryonia is characterized by having 
multiple, sufficiently resilient populations distributed across the 
spring systems historically occupied by the species for the species to 
be able to withstand catastrophic events. Species that are well-
distributed across their historical range are less susceptible to the 
risk of extirpation (Carroll et al. 2010, entire; Redford et al. 2011, 
entire). Currently, because there are two extant populations with 
moderate or high resiliency and two extirpated populations, redundancy 
of the species has been reduced from historical levels. Additionally, 
the Quitobaquito tryonia has always been a highly localized endemic (it 
historically occupied springs occurring within a 1-kilometer (0.6-mile) 
radius of one another); the two extant populations are separated by 
roughly only 100 m (328 ft). Thus, a catastrophic event (such as 
drought) is highly likely to simultaneously affect both remaining 
populations of the Quitobaquito tryonia. Conversely, despite their 
proximity, the populations are isolated and not connected by overland 
flow; thus, some catastrophic events, such as the introduction of an 
invasive species, may only affect one of the two populations. However, 
this isolation would also limit the ability of the Quitobaquito tryonia 
to naturally recolonize given its limited dispersal ability. Because of 
the species' small size and dependence on water, dispersal events are 
rare and opportunistic, with overland transportation likely occurring 
by ``hitchhiking'' on birds or other animals (Hershler et al. 2005, pp. 
1755-1756, 1763). Therefore, species redundancy for the Quitobaquito 
tryonia is currently limited to two populations that occur within a 
reduced geographical extent, which reduces the species' ability to 
withstand catastrophic events.
    Representation reflects a species' capacity to adapt to changing 
environmental conditions over time and can be characterized by genetic 
and ecological diversity within and among populations. We describe 
species representation in terms of habitat variability across its 
historical range because data on the species' life history, 
demographics, and population genetics are lacking. Quitobaquito Springs 
has the greatest discharge of the four springs. It is possible that 
some local adaptation to water temperature, flow velocity, and/or 
community interactions occurred among the populations. Gene flow 
between populations is unlikely due to the isolation of separate 
springs and the species' limited dispersal ability. Because the species 
is limited in range and dispersal abilities and the spring habitats of 
its populations share several characteristics, the adaptive capacity, 
and thus the species' representation, is limited.
    As part of the SSA, we also developed two future condition 
scenarios at two time steps (10 years and 40 years into the future) to 
capture the range of uncertainties regarding future threats and the 
projected responses by the Quitobaquito tryonia. Our scenarios

[[Page 62733]]

assumed a continued rate changing climate conditions, water 
withdrawals, or drought that may impact groundwater levels and the rate 
of spring flow decline, as well as those factors at increased levels. 
Because we determined that the current condition of the Quitobaquito 
tryonia is consistent with an endangered species (see Determination of 
Status, below), we are not presenting the results of the future 
scenarios in this proposed rule. Please refer to the SSA report 
(Service 2022) for the full analysis of future scenarios.
    We note that, by using the SSA framework (Service 2016) to guide 
our analysis of the scientific information documented in the SSA 
report, we have analyzed the cumulative effects of identified threats 
and conservation actions on the species. To assess the current and 
future condition of the species, we evaluate the effects of all the 
relevant 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 habitat management actions can benefit the viability of the 
Quitobaquito tryonia by reducing or removing threats to the species. 
The concrete channel that was installed in 1989 (NPS 1992, pp. 28-30) 
created a more stable system within the spring population that is less 
affected by vegetation change, soil disturbance, and reductions/
fluctuations in preferred substrates. The concrete channel prevents 
establishment of dense vegetative stands that may impede flow, which is 
required to maintain species viability. Additionally, staff at Organ 
Pipe Cactus National Monument regularly remove dense aquatic vegetation 
from the spring channel to maintain stream flow and provide a mosaic of 
habitat types throughout the spring channel (Raymond et al. 2019, pp. 
18-19; Martin 2023a, pers comm.). Quitobaquito tryonia are less 
abundant in pool habitat and on aquatic vegetation compared to run or 
riffle habitat and on other substrates (Bogan 2018, entire; Williams 
and Sorensen 2019, p. 11; Sorensen 2021, pp. 5-8, 12). Aquatic 
vegetation removal may result in the loss of some Quitobaquito tryonia 
individuals, but this action is necessary to maintain flow of the 
spring channel.

Determination of Quitobaquito Tryonia'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 in danger of extinction throughout all or a significant portion 
of its range, and a ``threatened species'' as a species likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether a species meets the definition of an endangered 
species or a threatened species because of any of the following 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence.

Status Throughout All of Its Range

    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the Act's section 4(a)(1) 
factors, we find that although the Quitobaquito tryonia has 
sufficiently resilient extant populations, it has declined in number of 
populations from known historical levels. Our analysis revealed several 
factors that caused this decline and pose a meaningful risk to the 
viability of the species. These threats are primarily related to 
habitat changes (Factor A) and include the reduction of spring 
discharge and spring modification, in addition to effects of climate 
change (Factor E).
    The Quitobaquito tryonia is known from four historical populations, 
but two of those have become extirpated (Williams Spring and Burro 
Spring). As a narrow endemic species, it historically occupied springs 
occurring within a 1-kilometer (0.6-mile) radius. Because the Williams 
Spring and Burro Spring populations are extirpated, current redundancy 
of the species has been reduced 50 percent from historical levels. The 
Quitobaquito tryonia has always been a highly localized endemic, and 
the two extant populations (Quitobaquito Springs and Hillside Seep #2) 
are only separated by roughly 100 m (328 ft). Therefore, a catastrophic 
event, such as drought, is highly likely to simultaneously affect both 
remaining populations of the Quitobaquito tryonia.
    The most pervasive threat to the species is the historical and 
ongoing loss or decline in spring discharge. The species' populations 
at two springs (Burro Spring and Williams Spring) are extirpated 
because of a loss of perennial flow, while the Quitobaquito Springs 
complex has seen a documented decline in discharge. From January 2020 
to October 2021, daily mean discharge ranged from 26 to 51 lpm and 
averaged 35 lpm, which is a decrease from recorded levels from 1981 to 
1992 of 57 to 151 lpm and averaged 106 lpm (Carruth 1996, p. 15). 
Although discharge at Hillside Seep #2 has not been measured, it is a 
less wetted area and has even lower flow velocity than Quitobaquito 
Springs (AZGFD 2021, p. 3). The causes of the decline in spring 
discharge are likely related to ongoing drought conditions and 
groundwater pumping. Climate change is expected to exacerbate these 
conditions with increased temperatures, and more severe and frequent 
droughts. Historical modification of the spring complex has severely 
curtailed available habitat, and the loss of spring flow is ongoing and 
expected to continue (see figure 1, above).
    Despite their proximity, the populations are isolated and not 
connected by overland flow, and this isolation also limits the ability 
of the Quitobaquito tryonia to naturally recolonize given the species' 
lack of dispersal ability. Because of the species' small size and 
dependence on water, dispersal events are rare and opportunistic, with 
overland transportation likely occurring by ``hitchhiking'' on birds or 
other animals (Hershler et al. 2005, pp. 1755-1756, 1763). Therefore, 
gene flow between the populations is limited or nonexistent.
    In summary, the Quitobaquito tryonia is more susceptible to 
extirpation from catastrophic events and has reduced adaptive capacity. 
The number of known populations has already been reduced by 50 percent 
because of loss of spring flow, which is continuing to occur and is 
impacting the remaining two populations. The species is currently in 
danger of extinction because reduction of spring discharge, spring 
modification, and the effects of climate change are all risks that have 
historically impacted, and are currently impacting, the species and are 
reducing its viability across its range. We do not find the species 
meets the definition of a threatened species because the species has 
already shown declines in the number and resiliency of populations. Two 
of the four known populations have already become extirpated due to the 
threats mentioned above. Although

[[Page 62734]]

one population is currently in high condition and the other population 
is currently in moderate condition, both are currently experiencing 
impacts from the aforementioned threats. Because current redundancy is 
reduced from known historical levels, and representation is limited due 
to the close proximity of the two remaining populations, the species is 
vulnerable to catastrophic and stochastic events. Thus, after assessing 
the best available information, we determine that the Quitobaquito 
tryonia is in danger of extinction throughout all of its range.

Status Throughout a Significant Portion of Its Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. We have determined that the Quitobaquito tryonia is in 
danger of extinction throughout all of its range and accordingly did 
not undertake an analysis of any significant portion of its range. 
Because the Quitobaquito tryonia warrants listing as endangered 
throughout all of its range, our determination does not conflict with 
the decision in Center for Biological Diversity v. Everson, 435 F. 
Supp. 3d 69 (D.D.C. 2020), which vacated the provision 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) 
providing that if the Service determines that a species is threatened 
throughout all of its range, the Service will not analyze whether the 
species is endangered in a significant portion of its range.

Determination of Status

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

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition as a listed 
species, planning and implementation of recovery actions, requirements 
for Federal protection, and prohibitions against certain practices. 
Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies, 
including the Service, and the prohibitions against certain activities 
are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Section 4(f) of the Act calls for the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The goal of this process is to restore listed 
species to a point where they are secure, self-sustaining, and 
functioning components of their ecosystems.
    The recovery planning process begins with development of a recovery 
outline made available to the public soon after a final listing 
determination. The recovery outline guides the immediate implementation 
of urgent recovery actions while a recovery plan is being developed. 
Recovery teams (composed of species experts, Federal and State 
agencies, nongovernmental organizations, and stakeholders) may be 
established to develop and implement recovery plans. The recovery 
planning process involves the identification of actions that are 
necessary to halt and reverse the species' decline by addressing the 
threats to its survival and recovery. The recovery plan identifies 
recovery criteria for review of when a species may be ready for 
reclassification from endangered to threatened (``downlisting'') or 
removal from protected status (``delisting''), and methods for 
monitoring recovery progress. Recovery plans also establish a framework 
for agencies to coordinate their recovery efforts and provide estimates 
of the cost of implementing recovery tasks. Revisions of the plan may 
be done to address continuing or new threats to the species, as new 
substantive information becomes available. The recovery outline, draft 
recovery plan, final recovery plan, and any revisions will be available 
on our website as they are completed (https://www.fws.gov/program/endangered-species), or from our Arizona Ecological Services Field 
Office (see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    If this species is listed, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost-share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the State of Arizona would be 
eligible for Federal funds to implement management actions that promote 
the protection or recovery of the Quitobaquito tryonia. Information on 
our grant programs that are available to aid species recovery can be 
found at: https://www.fws.gov/service/financial-assistance.
    Although the Quitobaquito tryonia is only proposed for listing 
under the Act at this time, please let us know if you are interested in 
participating in recovery efforts for this species. Additionally, we 
invite you to submit any new information on this species whenever it 
becomes available and any information you may have for recovery 
planning purposes (see FOR FURTHER INFORMATION CONTACT).
    Section 7 of the Act is titled ``Interagency Cooperation'' and 
mandates all Federal action agencies to use their existing authorities 
to further the conservation purposes of the Act and to ensure that 
their actions are not likely to jeopardize the continued existence of 
listed species or adversely modify critical habitat. Regulations 
implementing section 7 are codified at 50 CFR part 402.
    Section 7(a)(2) states that each Federal action agency shall, in 
consultation with the Secretary, ensure that any action they authorize, 
fund, or carry out is not likely to jeopardize the continued existence 
of a listed species or result in the destruction or adverse 
modification of designated critical habitat. Each Federal agency shall 
review its action at the earliest possible time to determine whether it 
may affect listed species or critical habitat. If a determination is 
made that the action may affect listed species or critical habitat, 
formal

[[Page 62735]]

consultation is required (50 CFR 402.14(a)), unless the Service concurs 
in writing that the action is not likely to adversely affect listed 
species or critical habitat. At the end of a formal consultation, the 
Service issues a biological opinion, containing its determination of 
whether the Federal action is likely to result in jeopardy or adverse 
modification.
    In contrast, section 7(a)(4) of the Act requires Federal agencies 
to confer with the Service on any action that is likely to jeopardize 
the continued existence of any species proposed to be listed under the 
Act or result in the destruction or adverse modification of critical 
habitat proposed to be designated for such species. Although the 
conference procedures are required only when an action is likely to 
result in jeopardy or adverse modification, action agencies may 
voluntarily confer with the Service on actions that may affect species 
proposed for listing or critical habitat proposed to be designated. In 
the event that the subject species is listed or the relevant critical 
habitat is designated, a conference opinion may be adopted as a 
biological opinion and serve as compliance with section 7(a)(2) of the 
Act.
    Examples of discretionary actions for the Quitobaquito tryonia that 
may be subject to conference and consultation procedures under section 
7 of the Act are land management or other landscape-altering activities 
on Federal lands administered by the National Park Service as well as 
actions on State, Tribal, local, or private lands that require a 
Federal permit (such as a permit from the U.S. Army Corps of Engineers 
under section 404 of the Clean Water Act (33 U.S.C. 1251 et seq.) or a 
permit from the Service under section 10 of the Act) or that involve 
some other Federal action (such as funding from the Federal Highway 
Administration, Federal Aviation Administration, or the Federal 
Emergency Management Agency). Federal actions not affecting listed 
species or critical habitat--and actions on State, Tribal, local, or 
private lands that are not federally funded, authorized, or carried out 
by a Federal agency--do not require section 7 consultation. Federal 
agencies should coordinate with the local Service Field Office (see FOR 
FURTHER INFORMATION CONTACT) with any specific questions on section 7 
consultation and conference requirements.
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to endangered wildlife. 
The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR 
17.21, make it illegal for any person subject to the jurisdiction of 
the United States to commit, to attempt to commit, to solicit another 
to commit, or to cause to be committed any of the following: (1) Import 
endangered wildlife into, or export from, the United States; (2) take 
(which includes harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect, or to attempt to engage in any such conduct) 
endangered wildlife within the United States or on the high seas; (3) 
possess, sell, deliver, carry, transport, or ship, by any means 
whatsoever, any such wildlife that has been taken illegally; (4) 
deliver, receive, carry, transport, or ship in interstate or foreign 
commerce in the course of commercial activity; or (5) sell or offer for 
sale in interstate or foreign commerce. Certain exceptions to these 
prohibitions apply to employees or agents of the Service, the National 
Marine Fisheries Service, other Federal land management agencies, and 
State conservation agencies.
    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits for endangered wildlife are codified at 50 CFR 17.22. 
With regard to endangered wildlife, a permit may be issued for 
scientific purposes, for enhancing the propagation or survival of the 
species, or for take incidental to otherwise lawful activities. The 
statute also contains certain exemptions from the prohibitions, which 
are found in sections 9 and 10 of the Act.
    It is the policy of the Services, as published in the Federal 
Register on July 1, 1994 (59 FR 34272), to identify, to the extent 
known at the time a species is listed, specific activities that would 
not be considered likely to result in violation of section 9 of the 
Act. To the extent possible, activities that would be considered likely 
to result in violation would also be identified in as specific a manner 
as possible. The intent of this policy is to increase public awareness 
of the effect of a proposed listing on proposed and ongoing activities 
within the range of the species proposed for listing.
    At this time, we are unable to identify specific activities that 
would not be considered likely to result in a violation of section 9 of 
the Act beyond what is already clear from the descriptions of 
prohibitions or already excepted through our regulations at 50 CFR 
17.21 (e.g., 50 CFR 17.21(c)(2), which provides that any person may 
take endangered wildlife in defense of his own life or the lives of 
others). Also, as discussed above, certain activities that are 
prohibited under section 9 may be permitted under section 10 of the 
Act.
    To the extent currently known, the following is a list of examples 
of activities that would be considered likely to result in violation of 
section 9 of the Act in addition to what is already clear from the 
descriptions of the prohibitions found at 50 CFR 17.21:
    (1) Unauthorized handling or collecting of the Quitobaquito 
tryonia.
    (2) Destruction/alteration of Quitobaquito tryonia habitat by 
discharge of fill material, draining, ditching, tiling, pond 
construction, stream channelization or diversion, or removal or 
destruction of emergent aquatic vegetation; or diversion or alteration 
of surface or ground water flow into or out of the Quitobaquito Springs 
complex (i.e., due to roads, impoundments, discharge pipes, storm water 
detention basins, etc.) or in any body of water in which the 
Quitobaquito tryonia is known to occur.
    (3) Direct or indirect destruction of riparian habitat where the 
Quitobaquito tryonia occurs.
    (4) Introduction of nonnative species that compete with or prey 
upon the Quitobaquito tryonia, such as the introduction of nonnative 
fish and crayfish species into any waters in which the Quitobaquito 
tryonia is known to occur.
    (5) Release of biological control agents that attack any life stage 
of this species in or near Quitobaquito tryonia habitat.
    (6) Discharge of chemicals or fill material into any waters in 
which the Quitobaquito tryonia is known to occur.
    The list above is intended to be illustrative and not exhaustive; 
additional activities that would be considered likely to result in 
violation of section 9 of the Act may be identified during coordination 
with the local field office, and in some instances (e.g., with new or 
site-specific information), the Service may conclude that one or more 
activities identified here would not be considered likely to result in 
violation of section 9. Questions regarding whether specific activities 
would constitute violation of section 9 of the Act should be directed 
to the Arizona Ecological Services Field Office (see FOR FURTHER 
INFORMATION CONTACT).

II. Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features

[[Page 62736]]

    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Our regulations at 50 CFR 424.02 define the geographical area 
occupied by the species as an area that may generally be delineated 
around species' occurrences, as determined by the Secretary (i.e., 
range). Such areas may include those areas used throughout all or part 
of the species' life cycle, even if not used on a regular basis (e.g., 
migratory corridors, seasonal habitats, and habitats used periodically, 
but not solely by vagrant individuals).
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that each Federal action agency ensure, in 
consultation with the Service, that any action they authorize, fund, or 
carry out is not likely to result in the destruction or adverse 
modification of designated critical habitat. The designation of 
critical habitat does not affect land ownership or establish a refuge, 
wilderness, reserve, preserve, or other conservation area. Such 
designation also does not allow the government or public to access 
private lands. Such designation does not require implementation of 
restoration, recovery, or enhancement measures by non-Federal 
landowners. Rather, designation requires that, where a landowner 
requests Federal agency funding or authorization for an action that may 
affect an area designated as critical habitat, the Federal agency 
consult with the Service under section 7(a)(2) of the Act. If the 
action may affect the listed species itself (such as for occupied 
critical habitat), the Federal agency would have already been required 
to consult with the Service even absent the designation because of the 
requirement to ensure that the action is not likely to jeopardize the 
continued existence of the species. Even if the Service were to 
conclude after consultation that the proposed activity is likely to 
result in destruction or adverse modification of the critical habitat, 
the Federal action agency and the landowner are not required to abandon 
the proposed activity, or to restore or recover the species; instead, 
they must implement ``reasonable and prudent alternatives'' to avoid 
destruction or adverse modification of critical habitat.
    Under the first prong of the Act's definition of critical habitat, 
areas within the geographical area occupied by the species at the time 
it was listed are included in a critical habitat designation if they 
contain physical or biological features (1) which are essential to the 
conservation of the species and (2) which may require special 
management considerations or protection. For these areas, critical 
habitat designations identify, to the extent known using the best 
scientific data available, those physical or biological features that 
are essential to the conservation of the species (such as space, food, 
cover, and protected habitat).
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 
habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information from the SSA report and information developed during the 
listing process for the species. Additional information sources may 
include any generalized conservation strategy, criteria, or outline 
that may have been developed for the species; the recovery plan for the 
species; articles in peer-reviewed journals; conservation plans 
developed by States and counties; scientific status surveys and 
studies; biological assessments; other unpublished materials; or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. We recognize that critical habitat designated at a 
particular point in time may not include all of the habitat areas that 
we may later determine are necessary for the recovery of the species. 
For these reasons, a critical habitat designation does not signal that 
habitat outside the designated area is unimportant or may not be needed 
for recovery of the species. Areas that are important to the 
conservation of the species, both inside and outside the critical 
habitat designation, will continue to be subject to: (1) Conservation 
actions implemented under section 7(a)(1) of the Act; (2) regulatory 
protections afforded by the requirement in section 7(a)(2) of the Act 
for Federal agencies to ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species; and (3) the prohibitions found in section 9 of the Act. 
Federally funded or permitted projects affecting listed species outside 
their designated critical habitat areas may still result in jeopardy 
findings in some cases. These protections and conservation tools will 
continue to contribute to recovery of the species. Similarly, critical 
habitat designations made on the basis of the best available 
information at the time of designation will not control the direction 
and substance of future recovery plans, habitat conservation plans 
(HCPs), or other species conservation planning efforts if new 
information available at the time of those planning efforts calls for a 
different outcome.

Physical or Biological Features Essential to the Conservation of the 
Species

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12(b), in determining which areas we will designate as 
critical habitat from within the geographical area occupied by the 
species at the time of listing, we consider the physical or biological

[[Page 62737]]

features that are essential to the conservation of the species and 
which may require special management considerations or protection. The 
regulations at 50 CFR 424.02 define ``physical or biological features 
essential to the conservation of the species'' as the features that 
occur in specific areas and that are essential to support the life-
history needs of the species, including, but not limited to, water 
characteristics, soil type, geological features, sites, prey, 
vegetation, symbiotic species, or other features. A feature may be a 
single habitat characteristic or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity. For example, 
physical features essential to the conservation of the species might 
include gravel of a particular size required for spawning, alkaline 
soil for seed germination, protective cover for migration, or 
susceptibility to flooding or fire that maintains necessary early-
successional habitat characteristics. Biological features might include 
prey species, forage grasses, specific kinds or ages of trees for 
roosting or nesting, symbiotic fungi, or absence of a particular level 
of nonnative species consistent with conservation needs of the listed 
species. The features may also be combinations of habitat 
characteristics and may encompass the relationship between 
characteristics or the necessary amount of a characteristic essential 
to support the life history of the species.
    In considering whether features are essential to the conservation 
of the species, we may consider an appropriate quality, quantity, and 
spatial and temporal arrangement of habitat characteristics in the 
context of the life-history needs, condition, and status of the 
species. These characteristics include, but are not limited to, space 
for individual and population growth and for normal behavior; food, 
water, air, light, minerals, or other nutritional or physiological 
requirements; cover or shelter; sites for breeding, reproduction, or 
rearing (or development) of offspring; and habitats that are protected 
from disturbance.
    Brooded young, juvenile, and adult Quitobaquito tryonia all need 
adequate spring flow and water quality to meet their resource 
functions, which include feeding, growth, survival, and breeding 
(Hershler 1984, p. 68; Hershler and Sada 2002, p. 256; Martinez and 
Thome 2006, p. 14). Specifically, spring flow must be perennial to 
prevent desiccation and maintain stable water quality parameters.
    Quitobaquito tryonia need adequate periphyton growth for food. 
Tryonia species are likely herbivores or detritivores that primarily 
graze on periphyton and macrophytes by scraping surfaces with their 
file-like radula (Pyron and Brown 2015, pp. 386, 401). Periphyton is a 
mixture of algae, bacteria, detritus, fungi, diatoms, and protozoa 
contained within a polysaccharide matrix known as a biofilm that grows 
on exposed surfaces, such as macrophytes or substrate (Lysne et al. 
2007, p. 649). Production of periphyton and algae in a natural spring 
system is likely tied to water quality, nutrient availability, and 
exposure to sunlight (Brown et al. 2008, p. 488; Martinez and Thome 
2006, p. 14). Additionally, larger substrates (such as gravel or 
cobble) develop a richer periphyton coating than finer substrates 
(Brown and Lydeard 2010, p. 285). Therefore, periphyton is essential to 
the Quitobaquito tryonia because it is its primary food source.
    Suitable substrate is important for shelter and periphyton growth. 
Substrate characteristics influence the abundance and productivity of 
springsnails. Tryonia spp. appear to use a broad array of substrate 
types, including cobble, gravel, sand, and silt (Hershler et al. 2011, 
entire), although Quitobaquito tryonia appear to be most abundant on 
hard substrates within the spring channel at Quitobaquito Springs 
(Bogan 2018, entire). We assume that if a substrate type has a higher 
density of Quitobaquito tryonia, then that substrate is preferred by 
the species when compared to other suitable substrates. Presumed 
preferred substrates include hard and/or coarse substrates, such as 
cobble and gravel, which increase springsnail productivity by promoting 
robust periphyton growth. Other suitable substrate includes fine-
grained sediment, such as sand and silt. Suitable substrates still 
provide adequate food resources but are not as productive as presumed 
preferred substrates because of limited periphyton growth. Therefore, 
habitat with presumed preferred substrates or a combination of presumed 
preferred and suitable substrates is essential to the species.
    Aquatic vegetation is also important for shelter and periphyton 
growth. Vegetation density influences the abundance and productivity of 
springsnails. We assume that vegetation that occurs at lower densities 
is preferable to the Quitobaquito tryonia when compared to higher 
densities of vegetation. Important vegetation includes native 
macrophytes, such as sedges (Schoenoplectus spp.) and rushes (Juncus 
spp.), occurring at low densities that do not impede spring flow. Other 
native macrophytes may also be considered suitable for shelter and 
periphyton growth when they occur at higher densities. Therefore, 
habitat including aquatic vegetation present at levels that do not 
impede spring flow is essential to the species.
    The introduction of nonnative or invasive predators has the 
potential to negatively affect springsnails (Hershler 1998, p. 14; Sada 
2017, p. 11). The nonnative New Zealand mudsnail (Potamopyrgus 
antipodarum) is an invasive freshwater snail of the family Hydrobiidae 
that is known to compete with and slow the growth of native freshwater 
snails, including springsnails (Lysne and Koetsier 2008, pp. 103, 105; 
Lysne et al. 2007, pp. 647-653). New Zealand mudsnails may outcompete 
hydrobiid snails for food and shelter resources. Nonnative crayfish 
(notably Faxonius virilis and Procambarus clarkii) are known predators 
to springsnails and have been found in springs and streams at and near 
springsnail sites in Arizona. Crayfish have been found to consume 
snails that occupy similar habitats as springsnails and their eggs 
(Fernandez and Rosen 1996, pp. 24-25). Therefore, the absence of 
nonnative species, or a level of nonnative species low enough that it 
does not impede resource availability for or result in mortality of 
Quitobaquito tryonia individuals, is essential to the Quitobaquito 
tryonia.
    Tryonia and other springsnails show a pattern of decreasing 
abundance with distance from the spring source (Hershler and Sada 2002, 
p. 256; Martinez and Thome 2006, p. 14; Rogowski 2012, pp. 34, 37), 
indicating that water chemistry such as stable dissolved oxygen, pH, 
conductivity, and temperature, as well as absence of or low enough 
levels of contaminants, may influence the distribution and abundance of 
springsnails (O'Brien and Blinn 1999, pp. 231-232; Mladenka and 
Minshall 2001, pp. 209-211; Malcom et al. 2005, p. 75; Martinez and 
Thome 2006, pp. 12-15; Lysne et al. 2007, p. 650). However, the full 
suite of water quality conditions that the Quitobaquito tryonia prefers 
has not been determined. Nevertheless, we assume that overall 
sufficient water quality that provides appropriate conditions for the 
Quitobaquito tryonia is essential to the species.

[[Page 62738]]

Summary of Essential Physical or Biological Features

    We derive the specific physical or biological features essential to 
the conservation of the Quitobaquito tryonia from studies of the 
species' habitat, ecology, and life history as described below. 
Additional information can be found in the SSA report (Service 2022, 
entire; available on https://www.regulations.gov under Docket No. FWS-
R2-ES-2023-0073). We have determined that the following physical or 
biological features are essential to the conservation of the 
Quitobaquito tryonia:
    (1) Perennially free-flowing spring water with sufficient flow 
rate.
    (2) Sufficient amount of periphyton to support all life stages of 
the Quitobaquito tryonia.
    (3) Presence of hard or coarse substrates (including cobble and 
gravel) or a combination of coarse and fine substrates (including sand 
and/or silt).
    (4) Aquatic emergent and submergent vegetation, including native 
macrophytes such as sedges (Schoenoplectus spp.) and rushes (Juncus 
spp.), occurring at densities that do not impede spring flow.
    (5) Water quality parameters that support all life stages of the 
Quitobaquito tryonia, including:
    (a) Adequate levels of temperature, pH, and conductivity; and
    (b) Absence of contaminants, or a level of contaminants low enough 
that it does not negatively impact necessary water quality conditions 
for Quitobaquito tryonia individuals.
    (6) Absence of nonnative species, or a level of nonnative species 
low enough that it does not impede resource availability for or result 
in mortality of Quitobaquito tryonia individuals.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features which are essential to the conservation of 
the species and which may require special management considerations or 
protection. The features essential to the conservation of the 
Quitobaquito tryonia may require special management considerations or 
protection to reduce the following threats: (1) reduction of spring 
discharge, (2) effects of climate change, and (3) spring modification.
    Management activities that could ameliorate these threats and 
protect the quantity and quality of the habitat include, but are not 
limited to: (1) decreasing groundwater pumping to maintain spring flow 
that supports spring habitat; (2) removing dense aquatic vegetation 
from the spring channel to maintain stream flow and provide a mosaic of 
habitat types throughout the spring channel; and (3) controlling and 
removing introduced nonnative predators and competitors, such as 
crayfish.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available to designate critical habitat. In accordance 
with the Act and our implementing regulations at 50 CFR 424.12(b), we 
review available information pertaining to the habitat requirements of 
the species and identify specific areas within the geographical area 
occupied by the species at the time of listing and any specific areas 
outside the geographical area occupied by the species to be considered 
for designation as critical habitat. We are not currently proposing to 
designate any areas outside the geographical area occupied by the 
species because we have not identified any unoccupied areas that meet 
the definition of critical habitat. No unoccupied areas have at least 
one essential physical or biological feature and a reasonable certainty 
of contributing to conservation of the species.
    In order to analyze possible habitat locations, in November 2018, 
several seeps to the northwest of Quitobaquito Springs were surveyed, 
but none had perennial spring flow (Williams and Sorensen 2019, p. 9), 
which is essential for the Quitobaquito tryonia. In October 2020, two 
seeps east of Quitobaquito Pond were surveyed; Quitobaquito tryonia 
were detected at only Hillside Seep #2, one of the two surveyed 
locations. In November 2021, several additional seeps east of 
Quitobaquito Pond were surveyed and Hillside Seep #1 and #2 were 
revisited. Five seeps had low flow and possible springsnail habitat, 
but no Quitobaquito tryonia were found (Sorensen 2021, p. 10). There 
are other unnamed seeps that occur within the broader Quitobaquito 
Springs area that have yet to be fully surveyed for the Quitobaquito 
tryonia, but none of them occur in the historical range of the species. 
It is unknown how many seeps in the area have the perennial flow 
necessary for brooded young, juvenile, and adult Quitobaquito tryonia 
to meet their resource functions, which include feeding, growth, 
survival, and breeding (Service 2022, p. 13). Specifically, spring flow 
must be perennial to prevent desiccation and maintain stable water 
quality parameters (Hershler 1984, p. 68; Hershler and Sada 2002, p. 
256; Johnson et al. 2013, p. 248; Martinez and Thome 2006, p. 14). 
Therefore, for a seep to be suitable habitat and have reasonable 
certainty that it would contribute to the conservation of the 
Quitobaquito tryonia, it must contain the essential physical or 
biological feature of perennially free-flowing spring water with 
sufficient flow rate. In the current condition and in all plausible 
future scenarios, it is unlikely that any of the seeps in the area 
would contain or be able to be managed to achieve the spring flow 
necessary for the Quitobaquito tryonia, especially when conditions are 
exacerbated by climate change. Accordingly, for those springs that 
occur outside of the historical range, we cannot identify the exact 
habitat parameters that will ensure the success of the species there. 
Therefore, there are no areas other than those included in this 
proposed critical habitat designation that we are reasonably certain 
would contribute to the conservation of the Quitobaquito tryonia.
    We are proposing to designate critical habitat units that we have 
determined based on the best scientific data available are known to be 
currently occupied and contain the physical or biological features 
essential to the conservation of the Quitobaquito tryonia. Additional 
areas outside the aquatic habitat within each subunit are included in 
the proposed designation to assist in maintaining the hydrology of the 
aquatic features. Sources of occupancy data on the Quitobaquito tryonia 
are from all available reports since monitoring of the species began in 
2002 (Martinez and Sorensen 2016, entire; Bogan 2018, entire; Williams 
and Sorensen 2019, entire; AZGFD 2021, entire; Sorensen 2022, entire). 
We determined localities to be occupied at the time of listing if they 
are identified as extant in the SSA report (Service 2022, pp. 16-20). 
Extirpated populations are not included because the spring sources that 
supported them no longer have the essential physical or biological 
features to support the species now or in the future. Specifically, 
these areas no longer have water, and it is unlikely that groundwater 
would support spring flow in these areas.
    We obtained information on ecology and habitat requirements of the 
Quitobaquito tryonia from multiple sources, as identified in the SSA 
report as explained above (Service 2022, pp. 7-13). For mapping of 
proposed critical habitat, we used Organ Pipe Cactus

[[Page 62739]]

National Monument geo-referenced data of aquatic habitats that have 
perennial spring flow, adequate water quality, and substrates and 
aquatic vegetation that support extant populations of the Quitobaquito 
tryonia. There are two areas that contain the physical or biological 
features needed by the Quitobaquito tryonia: a human-made concrete 
spring run and a natural seep. We delineated the extent of critical 
habitat along the spring run by the physical boundary of the concrete 
channel and southwest spring trench with an average width of 2 m (6.4 
ft) along this length to capture areas where water pools along the 
channel. Water provided by the springs does not flow outside of this 
human-made channel and corresponding pools. For Hillside Seep #2, we 
delineated the extent of critical habitat along the seep from the point 
of origin of the seep downhill a distance of 15.2 m (50 ft), which is 
the longest known length of flow from the seep (Service 2022, p. 20). 
We included all area within 5 m (16.4 ft) of this length to capture any 
future hydrological changes of flow patterns that may occur over time 
in this area, both upslope and downslope of the seep. This also 
captures the habitat associated with the upslope and downslope of the 
watershed. In other words, this area incorporates most of the habitat 
that has the potential to impact the seep and any Quitobaquito tryonia 
individuals depending on that seep (Martin 2023b, pers. comm.). We used 
two different methods because the water in the channel is confined 
within a human-made concrete structure, and the seep is naturally 
occurring, so there is more variability in width of sheet flow 
(overland storm runoff).
    In summary, for areas within the geographical area occupied by the 
species at the time of listing, we delineated critical habitat unit 
boundaries using the following criteria:
    (1) We compiled all available data from observations of the 
Quitobaquito tryonia;
    (2) We identified, based on the best scientific data available, 
populations that are extant at the time of listing (current) versus 
those that are extirpated;
    (3) We identified areas containing the components comprising the 
essential physical or biological features that may require special 
management considerations or protection; and
    (4) We circumscribed boundaries of potential critical habitat based 
on the above information that reflect current habitat conditions.
    While the human-made concrete spring run that provides habitat for 
the Quitobaquito tryonia is included in the proposed critical habitat 
designation for the species, when determining proposed critical habitat 
boundaries, we made every effort to avoid including other developed 
areas such as lands covered by buildings, pavement, and other 
structures because such lands lack physical or biological features 
necessary for the Quitobaquito tryonia. The scale of the maps we 
prepared under the parameters for publication within the Code of 
Federal Regulations may not reflect the exclusion of such other 
developed lands. Any such lands inadvertently left inside critical 
habitat boundaries shown on the maps of this proposed rule have been 
excluded by text in the proposed rule and are not proposed for 
designation as critical habitat. Therefore, if the critical habitat is 
finalized as proposed, a Federal action involving these lands would not 
trigger section 7 consultation with respect to critical habitat and the 
requirement of no adverse modification unless the specific action would 
affect the physical or biological features in the adjacent critical 
habitat. We propose to designate as critical habitat areas that we have 
determined are occupied at the time of listing (i.e., currently 
occupied) and that contain one or more of the physical or biological 
features that are essential to support the life-history processes of 
the species.
    One unit, composed of two subunits, is proposed for designation 
based on one or more of the physical or biological features being 
present to support the Quitobaquito tryonia's life-history processes. 
Both subunits contain all of the identified physical or biological 
features and support multiple life-history processes.
    The proposed critical habitat designation is defined by the map, as 
modified by any accompanying regulatory text, presented at the end of 
this document under Proposed Regulation Promulgation. We include more 
detailed information on the boundaries of the critical habitat 
designation in the preamble of this document. We will make the 
coordinates or plot points or both on which the map is based available 
to the public on https://www.regulations.gov at Docket No. FWS-R2-ES-
2023-0073 and on our internet site at https://www.fws.gov/office/arizona-ecological-services.

Proposed Critical Habitat Designation

    We are proposing one unit, composed of two subunits, as critical 
habitat for the Quitobaquito tryonia. The critical habitat area we 
describe below constitutes our current best assessment of areas that 
meet the definition of critical habitat for the Quitobaquito tryonia. 
Table 2 shows the proposed critical habitat unit and the approximate 
area of each subunit. Both subunits of the Quitobaquito Unit are 
occupied.

                      Table 2--Proposed Critical Habitat Unit for the Quitobaquito Tryonia
                      [Area estimates reflect all area within critical habitat boundaries]
----------------------------------------------------------------------------------------------------------------
                                                                            Size of Unit in
      Critical Habitat Unit        Critical Habitat    Land Ownership by        Feet\2\            Occupied?
                                        Subunit              Type             (Meters\2\)
----------------------------------------------------------------------------------------------------------------
Quitobaquito Unit...............  A. Spring Channel.  Federal (NPS).....  4,455 (414).......  Yes.
                                  B. Hillside Seep    Federal (NPS).....  1,640 (152).......  Yes.
                                   #2.
                                 -------------------------------------------------------------------------------
    Total.......................  ..................  ..................  6,095 (566)
----------------------------------------------------------------------------------------------------------------
Note: Area sizes may not sum due to rounding.

    We present brief descriptions of both subunits, and reasons why 
they meet the definition of critical habitat for the Quitobaquito 
tryonia, below.

Subunit A: Spring Channel

    Subunit A in the Quitobaquito Unit consists of 4,455 square feet 
(ft\2\) (414 square meters (m\2\)) of the spring channel. This subunit 
is occupied and contains all of the physical or biological features 
essential to the conservation of the species. This subunit is entirely 
on Federal (NPS) land within Organ Pipe Cactus National Monument. 
Threats that are occurring in this area include decline in spring flow 
from groundwater withdrawal and drought, effects of

[[Page 62740]]

climate change, and spring modification. This subunit may require 
special management considerations, such as vegetation removal, and to 
the extent possible, protection from future groundwater withdrawals in 
close proximity. NPS is already actively managing this unit by 
periodically removing a portion of emergent and submerged vegetation to 
improve water flow from the spring source, and NPS has worked with U.S. 
Customs and Border Protection on placement of wells for border 
construction activities.

Subunit B: Hillside Seep #2

    Subunit B in the Quitobaquito Unit consists of 1,640 ft\2\ (152 
m\2\) of a seep located approximately 338 ft (103 m) from the spring 
channel. This subunit is occupied and contains all of the physical or 
biological features essential to the conservation of the species. This 
subunit is entirely on Federal (NPS) land within Organ Pipe Cactus 
National Monument. Threats that are occurring in this area include 
decline in spring flow from groundwater withdrawal and drought, effects 
of climate change, and spring modification. This subunit may require 
the same special management considerations and protection as Subunit A. 
The NPS may manage this unit similar to the management discussed for 
Subunit A by periodically removing a portion of emergent and submerged 
vegetation.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they authorize, fund, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species. In 
addition, section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any agency action which is likely to 
jeopardize the continued existence of any species proposed to be listed 
under the Act or result in the destruction or adverse modification of 
proposed critical habitat.
    We published a final rule revising the definition of destruction or 
adverse modification on August 27, 2019 (84 FR 44976). Destruction or 
adverse modification means a direct or indirect alteration that 
appreciably diminishes the value of critical habitat as a whole for the 
conservation of a listed species.
    Compliance with the requirements of section 7(a)(2) is documented 
through our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect, and 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species and/or 
destroy or adversely modify critical habitat, we provide reasonable and 
prudent alternatives to the project, if any are identifiable, that 
would avoid the likelihood of jeopardy and/or destruction or adverse 
modification of critical habitat. We define ``reasonable and prudent 
alternatives'' (at 50 CFR 402.02) as alternative actions identified 
during consultation that:
    (1) Can be implemented in a manner consistent with the intended 
purpose of the action,
    (2) Can be implemented consistent with the scope of the Federal 
agency's legal authority and jurisdiction,
    (3) Are economically and technologically feasible, and
    (4) Would, in the Service Director's opinion, avoid the likelihood 
of jeopardizing the continued existence of the listed species and/or 
avoid the likelihood of destroying or adversely modifying critical 
habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    Regulations at 50 CFR 402.16 set forth requirements for Federal 
agencies to reinitiate consultation if any of the following four 
conditions occur: (1) the amount or extent of taking specified in the 
incidental take statement is exceeded; (2) new information reveals 
effects of the action that may affect listed species or critical 
habitat in a manner or to an extent not previously considered; (3) the 
identified action is subsequently modified in a manner that causes an 
effect to the listed species or critical habitat that was not 
considered in the biological opinion or written concurrence; or (4) a 
new species is listed or critical habitat designated that may be 
affected by the identified action. The reinitiation requirement applies 
only to actions that remain subject to some discretionary Federal 
involvement or control. As provided in 50 CFR 402.16, the requirement 
to reinitiate consultations for new species listings or critical 
habitat designation does not apply to certain agency actions (e.g., 
land management plans issued by the Bureau of Land Management in 
certain circumstances).

Application of the ``Destruction or Adverse Modification'' Standard

    The key factor related to the destruction or adverse modification 
determination is whether implementation of the proposed Federal action 
directly or indirectly alters the designated critical habitat in a way 
that appreciably diminishes the value of the critical habitat for the 
conservation of the listed species. As discussed above, the role of 
critical habitat is to support physical or biological features 
essential to the conservation of a listed species and provide for the 
conservation of the species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may violate section 
7(a)(2) of the Act by destroying or adversely modifying such habitat, 
or that may be affected by such designation.
    Activities that we may, during a consultation under section 7(a)(2) 
of the Act, consider likely to destroy or adversely modify critical 
habitat include, but are not limited to:
    (1) Actions that would decrease the amount of water available in 
the spring channel or seep used by the Quitobaquito tryonia. Such 
activities could include, but are not limited to, groundwater pumping, 
impoundment, and water diversion. These activities could decrease the 
amount of springflow so that the spring channel or seep becomes 
smaller, intermittent, or dry, and thereby could reduce the amount of 
space, prey, and cover available for Quitobaquito tryonia.
    (2) Actions that would alter habitat used by the Quitobaquito 
tryonia. Such actions could include the maintenance of springheads, 
stream or channel courses, and ponds. Maintaining springheads and 
human-made or natural spring channels will maximize the amount of 
springflow available to Quitobaquito tryonia. The spring channel that 
supports Quitobaquito tryonia was channelized and requires constant 
management to stop encroaching vegetation from completely filling in 
the channel.
    (3) Actions that would impact water quality of the spring system 
used by the Quitobaquito tryonia. Such activities could include, but 
are not limited to, presence of contaminants, livestock grazing, and 
spring modification.

[[Page 62741]]

Exemptions

Application of Section 4(a)(3) of the Act

    Section 4(a)(3)(B)(i) of the Act (16 U.S.C. 1533(a)(3)(B)(i)) 
provides that the Secretary shall not designate as critical habitat any 
lands or other geographical areas owned or controlled by the Department 
of Defense (DoD), or designated for its use, that are subject to an 
integrated natural resources management plan (INRMP) prepared under 
section 101 of the Sikes Act Improvement Act of 1997 (16 U.S.C. 670a), 
if the Secretary determines in writing that such plan provides a 
benefit to the species for which critical habitat is proposed for 
designation. No DoD lands with a completed INRMP are within the 
proposed critical habitat designation.

Consideration of Impacts Under Section 4(b)(2) of the Act

    Section 4(b)(2) of the Act states that the Secretary shall 
designate and make revisions to critical habitat on the basis of the 
best available scientific data after taking into consideration the 
economic impact, national security impact, and any other relevant 
impact of specifying any particular area as critical habitat. The 
Secretary may exclude an area from designated critical habitat based on 
economic impacts, impacts on national security, or any other relevant 
impacts. Exclusion decisions are governed by the regulations at 50 CFR 
424.19 and the Policy Regarding Implementation of Section 4(b)(2) of 
the Endangered Species Act (hereafter, the ``2016 Policy''; 81 FR 7226, 
February 11, 2016), both of which were developed jointly with the 
National Marine Fisheries Service (NMFS). We also refer to a 2008 
Department of the Interior Solicitor's opinion entitled, ``The 
Secretary's Authority to Exclude Areas from a Critical Habitat 
Designation under Section 4(b)(2) of the Endangered Species Act'' (M-
37016).
    In considering whether to exclude a particular area from the 
designation, we identify the benefits of including the area in the 
designation, identify the benefits of excluding the area from the 
designation, and evaluate whether the benefits of exclusion outweigh 
the benefits of inclusion. If the analysis indicates that the benefits 
of exclusion outweigh the benefits of inclusion, the Secretary may 
exercise discretion to exclude the area only if such exclusion would 
not result in the extinction of the species. In making the 
determination to exclude a particular area, the statute on its face, as 
well as the legislative history, are clear that the Secretary has broad 
discretion regarding which factor(s) to use and how much weight to give 
to any factor. In our final rules, we explain any decision to exclude 
areas, as well as decisions not to exclude, to make clear the rational 
basis for our decision. We describe below the process that we use for 
taking into consideration each category of impacts and any initial 
analyses of the relevant impacts.

Consideration of Economic Impacts

    Section 4(b)(2) of the Act and its implementing regulations require 
that we consider the economic impact that may result from a designation 
of critical habitat. To assess the probable economic impacts of a 
designation, we must first evaluate specific land uses or activities 
and projects that may occur in the area of the critical habitat. We 
then must evaluate the impacts that a specific critical habitat 
designation may have on restricting or modifying specific land uses or 
activities for the benefit of the species and its habitat within the 
areas proposed. We then identify which conservation efforts may be the 
result of the species being listed under the Act versus those 
attributed solely to the designation of critical habitat for this 
particular species. The probable economic impact of a proposed critical 
habitat designation is analyzed by comparing scenarios both ``with 
critical habitat'' and ``without critical habitat.''
    The ``without critical habitat'' scenario represents the baseline 
for the analysis, which includes the existing regulatory and socio-
economic burden imposed on landowners, managers, or other resource 
users potentially affected by the designation of critical habitat 
(e.g., under the Federal listing as well as other Federal, State, and 
local regulations). Therefore, the baseline represents the costs of all 
efforts attributable to the listing of the species under the Act (i.e., 
conservation of the species and its habitat incurred regardless of 
whether critical habitat is designated). The ``with critical habitat'' 
scenario describes the incremental impacts associated specifically with 
the designation of critical habitat for the species. The incremental 
conservation efforts and associated impacts would not be expected 
without the designation of critical habitat for the species. In other 
words, the incremental costs are those attributable solely to the 
designation of critical habitat, above and beyond the baseline costs. 
These are the costs we use when evaluating the benefits of inclusion 
and exclusion of particular areas from the final designation of 
critical habitat should we choose to conduct a discretionary section 
4(b)(2) exclusion analysis.
    Executive Orders (E.O.s) 12866 and 13563 direct Federal agencies to 
assess the costs and benefits of available regulatory alternatives in 
quantitative (to the extent feasible) and qualitative terms. Executive 
Order 14094 reaffirms the principles of E.O. 12866 and E.O. 13563 and 
states that regulatory analysis should facilitate agency efforts to 
develop regulations that serve the public interest, advance statutory 
objectives, and are consistent with E.O. 12866, E.O. 13563, and the 
Presidential Memorandum of January 20, 2021 (Modernizing Regulatory 
Review). Consistent with the E.O. regulatory analysis requirements, our 
effects analysis under the Act may take into consideration impacts to 
both directly and indirectly affected entities, where practicable and 
reasonable. If sufficient data are available, we assess to the extent 
practicable the probable impacts to both directly and indirectly 
affected entities. Section 3(f) of E.O. 12866, as amended by E.O. 
14094, identifies four criteria when a regulation is considered a 
``significant regulatory action'' and requires additional analysis, 
review, and approval if met. The criterion relevant here is whether the 
designation of critical habitat may have an economic effect of $200 
million or more in any given year (section 3(f)(1)). Therefore, our 
consideration of economic impacts uses a screening analysis to assess 
whether a designation of critical habitat for the Quitobaquito tryonia 
is likely to exceed the economically significant threshold.
    For this particular designation, we developed an incremental 
effects memorandum (IEM) considering the probable incremental economic 
impacts that may result from this proposed designation of critical 
habitat. The information contained in our IEM was then used to develop 
a screening analysis of the probable effects of the designation of 
critical habitat for the Quitobaquito tryonia (IEc 2023, entire). We 
began by conducting a screening analysis of the proposed designation of 
critical habitat in order to focus our analysis on the key factors that 
are likely to result in incremental economic impacts. The purpose of 
the screening analysis is to filter out particular geographical areas 
of critical habitat that are already subject to such protections and 
are, therefore, unlikely to incur incremental economic impacts. In 
particular, the screening analysis considers baseline costs (i.e., 
absent critical habitat designation) and includes any probable 
incremental economic impacts where land and water use may already be 
subject to

[[Page 62742]]

conservation plans, land management plans, best management practices, 
or regulations that protect the habitat area as a result of the Federal 
listing status of the species. Ultimately, the screening analysis 
allows us to focus our analysis on evaluating the specific areas or 
sectors that may incur probable incremental economic impacts as a 
result of the designation.
    The presence of the listed species in occupied areas of critical 
habitat means that any destruction or adverse modification of those 
areas is also likely to jeopardize the continued existence of the 
species. Therefore, designating occupied areas as critical habitat 
typically causes little if any incremental impacts above and beyond the 
impacts of listing the species. As a result, we generally focus the 
screening analysis on areas of unoccupied critical habitat (unoccupied 
units or unoccupied areas within occupied units). Overall, the 
screening analysis assesses whether designation of critical habitat is 
likely to result in any additional management or conservation efforts 
that may incur incremental economic impacts. This screening analysis 
combined with the information contained in our IEM constitute what we 
consider to be our draft economic analysis (DEA) of the proposed 
critical habitat designation for the Quitobaquito tryonia; our DEA is 
summarized in the narrative below.
    As part of our screening analysis, we considered the types of 
economic activities that are likely to occur within the areas likely 
affected by the critical habitat designation. In our evaluation of the 
probable incremental economic impacts that may result from the proposed 
designation of critical habitat for the Quitobaquito tryonia, first we 
identified, in the IEM dated March 8, 2023, probable incremental 
economic impacts associated with the following categories of 
activities: (1) Federal lands management (NPS, Organ Pipe Cactus 
National Monument); (2) groundwater pumping; and (3) border security 
operations (U.S. Customs and Border Protection). We considered each 
industry or category individually. Additionally, we considered whether 
their activities have any Federal involvement. Critical habitat 
designation generally will not affect activities that do not have any 
Federal involvement; under the Act, designation of critical habitat 
only affects activities conducted, funded, permitted, or authorized by 
Federal agencies. If we list the species, in areas where the 
Quitobaquito tryonia is present, Federal agencies would be required to 
consult with the Service under section 7 of the Act on activities they 
authorize, fund, or carry out that may affect the species. If, when we 
list the species, we also finalize this proposed critical habitat 
designation, Federal agencies would be required to consider the effects 
of their actions on the designated habitat, and if the Federal action 
may affect critical habitat, our consultations would include an 
evaluation of measures to avoid the destruction or adverse modification 
of critical habitat.
    In our IEM, we attempted to clarify the distinction between the 
effects that would result from the species being listed and those 
attributable to the critical habitat designation (i.e., difference 
between the jeopardy and adverse modification standards) for the 
Quitobaquito tryonia's critical habitat. Because the designation of 
critical habitat for the Quitobaquito tryonia is being proposed 
concurrently with the listing, it has been our experience that it is 
more difficult to discern which conservation efforts are attributable 
to the species being listed and those which would result solely from 
the designation of critical habitat. However, the following specific 
circumstances in this case help to inform our evaluation: (1) The 
essential physical or biological features identified for critical 
habitat are the same features essential for the life requisites of the 
species, and (2) any actions that would likely adversely affect the 
essential physical or biological features of occupied critical habitat 
are also likely to adversely affect the species itself. The IEM 
outlines our rationale concerning this limited distinction between 
baseline conservation efforts and incremental impacts of the 
designation of critical habitat for this species. This evaluation of 
the incremental effects has been used as the basis to evaluate the 
probable incremental economic impacts of this proposed designation of 
critical habitat.
    The proposed critical habitat designation for the Quitobaquito 
tryonia consists of a single unit with two subunits currently occupied 
by the species. We are not proposing to designate any units of 
unoccupied habitat. The proposed Quitobaquito Unit totals 6,095 square 
feet (566 square meters) and is entirely within federally owned land at 
Organ Pipe Cactus National Monument. In this area, any actions that may 
affect the species or its habitat would also affect designated critical 
habitat, and it is unlikely that there would be any additional 
recommendations or project modifications to avoid adversely modifying 
critical habitat above those we would recommend for avoiding jeopardy. 
Therefore, only administrative costs of conducting any section 7 
consultation are expected in all of the proposed critical habitat 
designation. While this additional analysis will require time and 
resources by both the Federal action agency and the Service, it is 
believed that, in most circumstances, these costs would predominantly 
be administrative in nature and would not be significant.
    We estimate that approximately one informal consultation may occur 
annually in proposed critical habitat areas. Annual incremental costs 
to the Service, Federal action agencies, and third parties associated 
with this consultation are anticipated to be approximately $2,600. The 
designation of critical habitat for the Quitobaquito tryonia, which is 
located on Federal lands, is not expected to trigger additional 
requirements under State or local regulations, nor is the designation 
expected to have perceptional effects on markets. Additional section 7 
efforts to conserve the Quitobaquito tryonia are not predicted to 
result from the designation of critical habitat. As this economic 
screening analysis finds that the designation is not likely to result 
in additional or different project modifications, ancillary economic 
benefits are not anticipated. The above-mentioned administrative costs 
are highly unlikely to exceed $200 million in a given year.
    We are soliciting data and comments from the public on the DEA 
discussed above. During the development of a final designation, we will 
consider the information presented in the DEA and any additional 
information on economic impacts we receive during the public comment 
period to determine whether any specific areas should be excluded from 
the final critical habitat designation under authority of section 
4(b)(2) of the Act, our implementing regulations at 50 CFR 424.19, and 
the 2016 Policy. We may exclude an area from critical habitat if we 
determine that the benefits of excluding the area outweigh the benefits 
of including the area, provided the exclusion will not result in the 
extinction of this species.

Consideration of National Security Impacts

    Section 4(a)(3)(B)(i) of the Act may not cover all DoD lands or 
areas that pose potential national-security concerns (e.g., a DoD 
installation that is in the process of revising its INRMP for a newly 
listed species or a species previously not covered). If a particular 
area is not covered under section 4(a)(3)(B)(i), then national-security 
or homeland-security concerns are not a factor in the process of 
determining what areas meet the definition of

[[Page 62743]]

``critical habitat.'' However, the Service must still consider impacts 
on national security, including homeland security, on those lands or 
areas not covered by section 4(a)(3)(B)(i) because section 4(b)(2) 
requires the Service to consider those impacts whenever it designates 
critical habitat. Accordingly, if DoD, Department of Homeland Security 
(DHS), or another Federal agency has requested exclusion based on an 
assertion of national-security or homeland-security concerns, or we 
have otherwise identified national-security or homeland-security 
impacts from designating particular areas as critical habitat, we 
generally have reason to consider excluding those areas.
    However, we cannot automatically exclude requested areas. When DoD, 
DHS, or another Federal agency requests exclusion from critical habitat 
on the basis of national-security or homeland-security impacts, we must 
conduct an exclusion analysis if the Federal requester provides 
information, including a reasonably specific justification of an 
incremental impact on national security that would result from the 
designation of that specific area as critical habitat. That 
justification could include demonstration of probable impacts, such as 
impacts to ongoing border-security patrols and surveillance activities, 
or a delay in training or facility construction, as a result of 
compliance with section 7(a)(2) of the Act. If the agency requesting 
the exclusion does not provide us with a reasonably specific 
justification, we will contact the agency to recommend that it provide 
a specific justification or clarification of its concerns relative to 
the probable incremental impact that could result from the designation. 
If we conduct an exclusion analysis because the agency provides a 
reasonably specific justification or because we decide to exercise the 
discretion to conduct an exclusion analysis, we will defer to the 
expert judgment of DoD, DHS, or another Federal agency as to: (1) 
Whether activities on its lands or waters, or its activities on other 
lands or waters, have national-security or homeland-security 
implications; (2) the importance of those implications; and (3) the 
degree to which the cited implications would be adversely affected in 
the absence of an exclusion. In that circumstance, in conducting a 
discretionary section 4(b)(2) exclusion analysis, we will give great 
weight to national-security and homeland-security concerns in analyzing 
the benefits of exclusion.
    In preparing this proposal, we have determined that the lands 
within the proposed designation of critical habitat for Quitobaquito 
tryonia are not owned or managed by the DoD or DHS, and, therefore, we 
anticipate no impact on national security or homeland security.

Consideration of Other Relevant Impacts

    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts on national 
security discussed above. To identify other relevant impacts that may 
affect the exclusion analysis, we consider a number of factors, 
including whether there are permitted conservation plans covering the 
species in the area--such as HCPs, safe harbor agreements, or candidate 
conservation agreements with assurances--or whether there are non-
permitted conservation agreements and partnerships that may be impaired 
by designation of, or exclusion from, critical habitat. In addition, we 
look at whether Tribal conservation plans or partnerships, Tribal 
resources, or government-to-government relationships of the United 
States with Tribal entities may be affected by the designation. We also 
consider any State, local, social, or other impacts that might occur 
because of the designation.

Summary of Exclusions Considered Under Section 4(b)(2) of the Act

    In preparing this proposal, we have determined that no HCPs or 
other management plans for the Quitobaquito tryonia currently exist, 
and the proposed designation does not include any Tribal lands or trust 
resources or any lands for which designation would have any economic or 
national security impacts. Therefore, we anticipate no impact on Tribal 
lands, partnerships, or HCPs from this proposed critical habitat 
designation; thus, as described above, we are not considering excluding 
any particular areas from the designation on the basis of the presence 
of conservation agreements or impacts to trust resources.
    However, if through the public comment period we receive 
information that we determine indicates that there are potential 
economic, national security, or other relevant impacts from designating 
particular areas as critical habitat, then as part of developing the 
final designation of critical habitat, we will evaluate that 
information and may conduct a discretionary exclusion analysis to 
determine whether to exclude those areas under the authority of section 
4(b)(2) of the Act and our implementing regulations at 50 CFR 424.19. 
If we receive a request for exclusion of a particular area and after 
evaluation of supporting information we do not exclude, we will fully 
describe our decision in the final rule for this action.

Required Determinations

Clarity of the Rule

    We are required by E.O.s 12866 and 12988 and by the Presidential 
Memorandum of June 1, 1998, to write all rules in plain language. This 
means that each rule we publish must:
    (1) Be logically organized;
    (2) Use the active voice to address readers directly;
    (3) Use clear language rather than jargon;
    (4) Be divided into short sections and sentences; and
    (5) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in ADDRESSES. To better help us 
revise the rule, your comments should be as specific as possible. For 
example, you should tell us the numbers of the sections or paragraphs 
that are unclearly written, which sections or sentences are too long, 
the sections where you feel lists or tables would be useful, etc.

Regulatory Planning and Review (Executive Orders 12866, 13563, and 
14094)

    Executive Order (E.O.) 12866, as reaffirmed by E.O. 13563 and E.O. 
14094, provides that the Office of Information and Regulatory Affairs 
(OIRA) in the Office of Management and Budget (OMB) will review all 
significant rules. OIRA has determined that this rule is not 
significant.
    Executive Order 13563 reaffirms the principles of E.O. 12866 while 
calling for improvements in the Nation's regulatory system to promote 
predictability, to reduce uncertainty, and to use the best, most 
innovative, and least burdensome tools for achieving regulatory ends. 
The Executive order directs agencies to consider regulatory approaches 
that reduce burdens and maintain flexibility and freedom of choice for 
the public where these approaches are relevant, feasible, and 
consistent with regulatory objectives. E.O. 13563 emphasizes further 
that regulations must be based on the best available science and that 
the rulemaking process must allow for public participation and an open 
exchange of ideas.
    Executive Order 14094 reaffirms the principles of E.O. 12866 and 
E.O. 13563 and states that regulatory analysis should facilitate agency 
efforts to develop regulations that serve the

[[Page 62744]]

public interest, advance statutory objectives, and are consistent with 
E.O. 12866, E.O. 13563, and the Presidential Memorandum of January 20, 
2021 (Modernizing Regulatory Review). Regulatory analysis, as 
practicable and appropriate, shall recognize distributive impacts and 
equity, to the extent permitted by law.
    We have developed this proposed rule in a manner consistent with 
these requirements.

Regulatory Flexibility Act (5 U.S.C. 601 et seq.)

    Under the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et seq.), 
as amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (SBREFA; 5 U.S.C. 801 et seq.), whenever an agency is required to 
publish a notice of rulemaking for any proposed or final rule, it must 
prepare and make available for public comment a regulatory flexibility 
analysis that describes the effects of the rule on small entities 
(i.e., small businesses, small organizations, and small government 
jurisdictions). However, no regulatory flexibility analysis is required 
if the head of the agency certifies the rule will not have a 
significant economic impact on a substantial number of small entities. 
The SBREFA amended the RFA to require Federal agencies to provide a 
certification statement of the factual basis for certifying that the 
rule will not have a significant economic impact on a substantial 
number of small entities.
    According to the Small Business Administration, small entities 
include small organizations such as independent nonprofit 
organizations; small governmental jurisdictions, including school 
boards and city and town governments that serve fewer than 50,000 
residents; and small businesses (13 CFR 121.201). Small businesses 
include manufacturing and mining concerns with fewer than 500 
employees, wholesale trade entities with fewer than 100 employees, 
retail and service businesses with less than $5 million in annual 
sales, general and heavy construction businesses with less than $27.5 
million in annual business, special trade contractors doing less than 
$11.5 million in annual business, and agricultural businesses with 
annual sales less than $750,000. To determine whether potential 
economic impacts to these small entities are significant, we considered 
the types of activities that might trigger regulatory impacts under 
this designation as well as types of project modifications that may 
result. In general, the term ``significant economic impact'' is meant 
to apply to a typical small business firm's business operations.
    Under the RFA, as amended, and as understood in light of recent 
court decisions, Federal agencies are required to evaluate the 
potential incremental impacts of rulemaking on those entities directly 
regulated by the rulemaking itself; in other words, the RFA does not 
require agencies to evaluate the potential impacts to indirectly 
regulated entities. The regulatory mechanism through which critical 
habitat protections are realized is section 7 of the Act, which 
requires Federal agencies, in consultation with the Service, to ensure 
that any action authorized, funded, or carried out by the agency is not 
likely to destroy or adversely modify critical habitat. Therefore, 
under section 7, only Federal action agencies are directly subject to 
the specific regulatory requirement (avoiding destruction and adverse 
modification) imposed by critical habitat designation. Consequently, it 
is our position that only Federal action agencies would be directly 
regulated if we adopt the proposed critical habitat designation. The 
RFA does not require evaluation of the potential impacts to entities 
not directly regulated. Moreover, Federal agencies are not small 
entities. Therefore, because no small entities would be directly 
regulated by this rulemaking, the Service certifies that, if made final 
as proposed, the proposed critical habitat designation will not have a 
significant economic impact on a substantial number of small entities.
    In summary, we have considered whether the proposed designation 
would result in a significant economic impact on a substantial number 
of small entities. For the above reasons and based on currently 
available information, we certify that, if made final, the proposed 
critical habitat designation would not have a significant economic 
impact on a substantial number of small business entities. Therefore, 
an initial regulatory flexibility analysis is not required.

Energy Supply, Distribution, or Use--Executive Order 13211

    Executive Order 13211 (Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use) requires 
agencies to prepare statements of energy effects when undertaking 
certain actions. In our economic analysis, we did not find that this 
proposed critical habitat designation would significantly affect energy 
supplies, distribution, or use. Therefore, this action is not a 
significant energy action, and no statement of energy effects is 
required.

Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make the following finding:
    (1) This proposed rule would not produce a Federal mandate. In 
general, a Federal mandate is a provision in legislation, statute, or 
regulation that would impose an enforceable duty upon State, local, or 
Tribal governments, or the private sector, and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or Tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and Tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or Tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; Aid to Families 
with Dependent Children work programs; Child Nutrition; Food Stamps; 
Social Services Block Grants; Vocational Rehabilitation State Grants; 
Foster Care, Adoption Assistance, and Independent Living; Family 
Support Welfare Services; and Child Support Enforcement. ``Federal 
private sector mandate'' includes a regulation that ``would impose an 
enforceable duty upon the private sector, except (i) a condition of 
Federal assistance or (ii) a duty arising from participation in a 
voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal Government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions are not likely to destroy or adversely modify 
critical habitat under section 7. While non-Federal entities that 
receive Federal funding, assistance, or permits, or that otherwise 
require approval or authorization from a Federal agency for an action, 
may be indirectly impacted by the designation of critical habitat, the

[[Page 62745]]

legally binding duty to avoid destruction or adverse modification of 
critical habitat rests squarely on the Federal agency. Furthermore, to 
the extent that non-Federal entities are indirectly impacted because 
they receive Federal assistance or participate in a voluntary Federal 
aid program, the Unfunded Mandates Reform Act would not apply, nor 
would critical habitat shift the costs of the large entitlement 
programs listed above onto State governments.
    (2) We do not believe that this rule would significantly or 
uniquely affect small governments because it will not produce a Federal 
mandate of $200 million or greater in any year, that is, it is not a 
``significant regulatory action'' under the Unfunded Mandates Reform 
Act. The designation of critical habitat imposes no obligations on 
State or local governments. Therefore, a small government agency plan 
is not required.

Takings--Executive Order 12630

    In accordance with E.O. 12630 (Government Actions and Interference 
with Constitutionally Protected Private Property Rights), we have 
analyzed the potential takings implications of designating critical 
habitat for the Quitobaquito tryonia in a takings implications 
assessment. The Act does not authorize the Service to regulate private 
actions on private lands or confiscate private property as a result of 
critical habitat designation. Designation of critical habitat does not 
affect land ownership, or establish any closures, or restrictions on 
use of or access to the designated areas. Furthermore, the designation 
of critical habitat does not affect landowner actions that do not 
require Federal funding or permits, nor does it preclude development of 
habitat conservation programs or issuance of incidental take permits to 
permit actions that do require Federal funding or permits to go 
forward. However, Federal agencies are prohibited from carrying out, 
funding, or authorizing actions that would destroy or adversely modify 
critical habitat. A takings implications assessment has been completed 
for the proposed designation of critical habitat for the Quitobaquito 
tryonia, and it concludes that, if adopted, this designation of 
critical habitat does not pose significant takings implications for 
lands within or affected by the designation.

Federalism--Executive Order 13132

    In accordance with E.O. 13132 (Federalism), this proposed rule does 
not have significant Federalism effects. A federalism summary impact 
statement is not required. In keeping with Department of the Interior 
and Department of Commerce policy, we requested information from, and 
coordinated development of this proposed critical habitat designation 
with, appropriate State resource agencies. From a federalism 
perspective, the designation of critical habitat directly affects only 
the responsibilities of Federal agencies. The Act imposes no other 
duties with respect to critical habitat, either for States and local 
governments, or for anyone else. As a result, the proposed rule does 
not have substantial direct effects either on the States, or on the 
relationship between the Federal government and the States, or on the 
distribution of powers and responsibilities among the various levels of 
government. The proposed designation may have some benefit to these 
governments because the areas that contain the features essential to 
the conservation of the species are more clearly defined, and the 
physical or biological features of the habitat necessary for the 
conservation of the species are specifically identified. This 
information does not alter where and what federally sponsored 
activities may occur. However, it may assist State and local 
governments in long-range planning because they no longer have to wait 
for case-by-case section 7 consultations to occur.
    Where State and local governments require approval or authorization 
from a Federal agency for actions that may affect critical habitat, 
consultation under section 7(a)(2) of the Act would be required. While 
non-Federal entities that receive Federal funding, assistance, or 
permits, or that otherwise require approval or authorization from a 
Federal agency for an action, may be indirectly impacted by the 
designation of critical habitat, the legally binding duty to avoid 
destruction or adverse modification of critical habitat rests squarely 
on the Federal agency.

Civil Justice Reform--Executive Order 12988

    In accordance with E.O. 12988 (Civil Justice Reform), the Office of 
the Solicitor has determined that the rule would not unduly burden the 
judicial system and that it meets the requirements of sections 3(a) and 
3(b)(2) of the Order. We have proposed designating critical habitat in 
accordance with the provisions of the Act. To assist the public in 
understanding the habitat needs of the species, this proposed rule 
identifies the physical or biological features essential to the 
conservation of the species. The proposed areas of critical habitat is 
presented on a map, and the proposed rule provides several options for 
the interested public to obtain more detailed location information, if 
desired.

Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)

    This rule does not contain information collection requirements, and 
a submission to the Office of Management and Budget (OMB) under the 
Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.) is not 
required. We may not conduct or sponsor and you are not required to 
respond to a collection of information unless it displays a currently 
valid OMB control number.

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    Regulations adopted pursuant to section 4(a) of the Act are exempt 
from the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et 
seq.) and do not require an environmental analysis under NEPA. We 
published a notice outlining our reasons for this determination in the 
Federal Register on October 25, 1983 (48 FR 49244). This includes 
listing, delisting, and reclassification rules, as well as critical 
habitat designations. In a line of cases starting with Douglas County 
v. Babbitt, 48 F.3d 1495 (9th Cir. 1995), the courts have upheld this 
position.

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), E.O. 13175 (Consultation and Coordination 
with Indian Tribal Governments), and the Department of the Interior's 
manual at 512 DM 2, we readily acknowledge our responsibility to 
communicate meaningfully with federally recognized Tribes on a 
government-to-government basis. In accordance with Secretaries' Order 
3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal 
Trust Responsibilities, and the Endangered Species Act), we readily 
acknowledge our responsibilities to work directly with Tribes in 
developing programs for healthy ecosystems, to acknowledge that Tribal 
lands are not subject to the same controls as Federal public lands, to 
remain sensitive to Indian culture, and to make information available 
to Tribes. We have determined that no Tribal lands fall within the 
boundaries of the proposed critical habitat for the Quitobaquito 
tryonia, so no Tribal lands would be affected by the proposed 
designation.

[[Page 62746]]

References Cited

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

Authors

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

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

0
1. The authority citation for part 17 continues to read as follows:

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

0
2. In Sec.  17.11, in paragraph (h), amend the List of Endangered and 
Threatened Wildlife by adding an entry for ``Tryonia, Quitobaquito'' in 
alphabetical order under SNAILS to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                              Listing citations
           Common name               Scientific name        Where listed         Status         and applicable
                                                                                                    rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
                                                     Snails
 
                                                  * * * * * * *
Tryonia, Quitobaquito............  Tryonia              Wherever found.....  E               [Federal Register
                                    quitobaquitae.                                            citation when
                                                                                              published as a
                                                                                              final rule]; 50
                                                                                              CFR 17.95(f).\CH\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

0
3. In Sec.  17.95, amend paragraph (f) by adding an entry for 
``Quitobaquito Tryonia (Tryonia quitobaquitae)'' following the entry 
for ``Diamond tryonia (Pseudotryonia adamantina) and Gonzales tryonia 
(Tryonia circumstriata)'' to read as follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and Snails.
* * * * *
Quitobaquito Tryonia (Tryonia quitobaquitae)
    (1) The critical habitat unit and its subunits are depicted for 
Pima County, Arizona, on the map in this entry.
    (2) Within these areas, the physical or biological features 
essential to the conservation of the Quitobaquito tryonia consist of 
the following components:
    (i) Perennially free-flowing spring water with sufficient flow 
rate;
    (ii) Sufficient amount of periphyton to support all life stages of 
the Quitobaquito tryonia;
    (iii) Presence of hard or coarse substrates (including cobble and 
gravel) or a combination of coarse and fine substrates (including sand 
and/or silt);
    (iv) Aquatic emergent and submergent vegetation, including native 
macrophytes such as sedges (Schoenoplectus spp.) and rushes (Juncus 
spp.), occurring at densities that do not impede spring flow;
    (v) Water quality parameters that support all life stages of the 
Quitobaquito tryonia, including:
    (A) Adequate levels of temperature, pH, and conductivity; and
    (B) Absence of contaminants, or a level of contaminants low enough 
that it does not negatively impact necessary water quality conditions 
for Quitobaquito tryonia individuals; and
    (vi) Absence of nonnative species, or a level of nonnative species 
low enough that it does not impede resource availability for or result 
in mortality of Quitobaquito tryonia individuals.
    (3) Critical habitat includes the human-made concrete spring run 
that provides habitat for the Quitobaquito tryonia; critical habitat 
does not include other human-made structures (such as buildings, 
aqueducts, runways, roads, and other paved areas) and the land on which 
they are located existing within the legal boundaries on the effective 
date of the final rule.
    (4) Data layers defining map units were created using ESRI ArcGIS 
mapping software along with various spatial layers. We used ground-
truthed data provided by Organ Pipe Cactus National Monument staff that 
depicts all aquatic habitat used by the Quitobaquito tryonia, including 
southwest Quitobaquito Spring, a human-made trench that connects 
Quitobaquito Springs to a human-made channel, and a human-made channel 
that connects the southwest trench to the pond. ArcGIS was also used to 
calculate area in square feet and square meters, and was used to 
determine longitude and latitude coordinates in decimal degrees. The 
coordinate system used in mapping and calculating area and locations 
within the unit was Universal Transverse Mercator (UTM) conformal 
projection with 1983 North American Datum in Zone 12. The map in this 
entry, as modified by any accompanying regulatory text, establishes the 
boundaries of the critical habitat designation. The coordinates or plot 
points or both on which the map is based are available to the public at 
the Service's internet site at https://www.fws.gov/office/arizona-ecological-services, at https://www.regulations.gov at Docket No. FWS-
R2-ES-2023-0073, and at the field office responsible for this 
designation. You may obtain field office location information by 
contacting one of the Service regional offices, the addresses of which 
are listed at 50 CFR 2.2.
    (5) Quitobaquito Unit, Pima County, Arizona.
    (i) Quitobaquito Unit consists of two subunits:
    (A) Subunit A consists of 4,455 square feet (ft\2\) (414 square 
meters (m\2\)) of the spring channel. This subunit is entirely on 
federally owned land in Organ Pipe Cactus National Monument.
    (B) Subunit B consists of 1,640 ft\2\ (152 m\2\) of a seep located 
approximately 338 ft (103 m) from the spring channel. This subunit is 
entirely on federally owned land in Organ Pipe Cactus National 
Monument.
    (ii) Map of Quitobaquito Unit follows:

Figure 1 to Quitobaquito Tryonia (Tryonia quitobaquitae) paragraph (5)
BILLING CODE 4333-15-P

[[Page 62747]]

[GRAPHIC] [TIFF OMITTED] TP13SE23.002

* * * * *

Stephen Guertin,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-18547 Filed 9-12-23; 8:45 am]
BILLING CODE 4333-15-C