[Federal Register Volume 88, Number 161 (Tuesday, August 22, 2023)]
[Proposed Rules]
[Pages 57046-57060]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-17667]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R2-ES-2023-0069; FF09E21000 FXES1111090FEDR 234]
RIN 1018-BE77
Endangered and Threatened Wildlife and Plants; Endangered Species
Status for Toothless Blindcat and Widemouth Blindcat
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 toothless blindcat (Trogloglanis pattersoni) and widemouth
blindcat (Satan eurystomus), two cavefish species from the Edwards
Aquifer in Bexar County, Texas, as 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 toothless
blindcat and widemouth blindcat. After a review of the best available
scientific and commercial information, we find that listing both
species is warranted. If we finalize this rule as proposed, it would
extend the Act's protections to these species. We have determined that
designation of critical habitat is not prudent.
DATES: We will accept comments received or postmarked on or before
October 23, 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 6, 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-2023-0069,
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-2023-0069, 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 at https://www.regulations.gov at Docket No. FWS-R2-ES-2023-0069.
FOR FURTHER INFORMATION CONTACT: Karen Myers, Field Supervisor, U.S.
Fish and Wildlife Service, Austin Ecological Services Field Office,
1505 Ferguson Lane, Austin, TX 78754; telephone 512-937-7371.
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
toothless blindcat and widemouth blindcat both meet the definition of
an endangered species; therefore, we are proposing to list both as
such. Listing a species as an endangered or threatened species can be
completed only by issuing a rule through the Administrative Procedure
Act rulemaking process (5 U.S.C. 551 et seq.).
What this document does. We propose to list the toothless blindcat
and the widemouth blindcat as endangered species under the Act.
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 the toothless blindcat and
widemouth blindcat are endangered due to the threat of mortality from
groundwater well pumping (Factor E).
The toothless blindcat and the widemouth blindcat occupy a limited
range, and populations of both species have likely been severely
reduced since the introduction of groundwater wells in the late 19th to
early 20th centuries. The lethal discharge of the species through
groundwater wells could potentially impact the populations directly,
with an estimated cumulative loss of thousands of individuals.
Additionally, the assumed life history traits (such as increased age at
first reproduction, lower numbers of reproductively active females,
reduced numbers of eggs, slower growth rates, and longer life spans) of
both species make them more susceptible to long-term impacts on
demographic structure in the form of lower numbers of sexually mature
fish, reduced reproductive output, and diminished recruitment of
younger individuals.
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. We have determined
that designating critical habitat for the toothless blindcat and
widemouth blindcat is not prudent because the main driver of both
species' status is direct mortality resulting from groundwater well
pumping (Factor E). The wells constructed in blindcat habitat are not
affecting the species through habitat destruction or modification;
instead, it is the capture, entrainment, and death of individuals due
to uptake from groundwater well pumping that threatens the species.
Since we have determined that the present or threatened destruction,
modification, or curtailment of both species' habitats or range is not
a threat to the toothless blindcat or the widemouth blindcat, we
determine that designation of critical habitat is not prudent for the
species.
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
[[Page 57047]]
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, ranges, 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 ranges, including distribution patterns
and the locations of any additional populations of these species;
(d) Historical and current population levels, and current and
projected trends; and
(e) Past and ongoing conservation measures for these species, their
habitats, or both.
(2) Threats and conservation actions affecting these 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 these species.
(c) Existing regulations or conservation actions that may be
addressing threats to these species.
(3) Additional information concerning the historical and current
status of these species.
(4) Information regarding our determination that designating
critical habitat for the toothless blindcat and widemouth blindcat is
not prudent.
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 determinations 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 one or both of these
species is threatened instead of endangered, or we may conclude that
one or both of these species does not warrant listing as either an
endangered species or a threatened species. In our final rule, we will
clearly explain our rationale and the basis for our final decisions,
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 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
We identified the toothless blindcat and widemouth blindcat as
category 2 candidates in our December 30, 1982, candidate notice of
review (CNOR) (47 FR 58454). Category 2 candidates were defined as taxa
for which we had information indicating that proposing to list the
species was possibly appropriate, but for which substantial data were
not available to biologically support a proposed rule. Both species
remained so designated in subsequent CNORs (50 FR 37958, September 18,
1985; 54 FR 554, January 6, 1989; 56 FR 58804, November 21, 1991; 59 FR
58982, November 15, 1994). In our February 28, 1996, CNOR (61 FR 7596),
we discontinued the designation of category 2 species as candidates;
therefore, the toothless blindcat and widemouth blindcat were no longer
candidate species.
In August 1995, we received a petition from the American Society of
Ichthyologists and Herpetologists (ASIH) and the Desert Fishes Council.
The petition was to list three species, including the toothless
blindcat and widemouth blindcat (ASIH 1995, entire). Subsequently, in
1998, we published a 90-day finding that the petition did not present
substantial information indicating that these species warranted listing
(63 FR 48166; September 9, 1998).
On June 25, 2007, we received a petition dated June 18, 2007, from
Forest Guardians (now WildEarth Guardians) to list 475 species,
including the toothless blindcat and widemouth blindcat, in the
southwestern United States as endangered or threatened species and to
designate critical habitat under the Act (Forest Guardians 2007,
entire). 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
listing the toothless blindcat and widemouth blindcat may be warranted.
Peer Review
A species status assessment (SSA) team prepared an SSA report for
the toothless blindcat and widemouth blindcat. 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,
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we solicited independent scientific review of the information contained
in the toothless blindcat and widemouth blindcat SSA report (Service
2022, entire). We sent the SSA report to six independent peer reviewers
and received four responses. Results of this structured peer review
process can be found at https://www.regulations.gov under Docket No.
FWS-R2-ES-2023-0069. 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 four
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 content of the SSA report. The peer reviewers
generally concurred with our methods and conclusions, and provided
additional information, clarifications, and suggestions to improve the
SSA. One peer reviewer questioned assumptions related to groundwater
well mortality and habitat connectivity. Our review of the best
available information regarding the impact of anthropogenic mortality
(such as well mortality) on fish species similar to the toothless and
widemouth blindcats (that is, fish species that are subterranean, are
long-lived, and have reduced reproductive capacity) supports the
findings of the SSA.
I. Proposed Listing Determination
Background
A thorough review of the taxonomy, life history, and ecology of the
toothless blindcat (Trogloglanis pattersoni) and widemouth blindcat
(Satan eurystomus) is presented in the SSA report (Service 2022,
entire).
The toothless blindcat and widemouth blindcat are cavefish endemic
to the San Antonio segment of the Edwards Aquifer in Bexar County,
Texas. They inhabit a deep, inaccessible subterranean region of the
aquifer, with all known specimens of both species having been collected
from groundwater wells at depths at or greater than 308 meters (m)
(1,010 feet (ft)). The toothless blindcat and the widemouth blindcat
are members of the catfish (Siluriformes) family Ictaluridae, and are
the only members of their respective genera, Trogloglanis and Satan
(Arce-H et al. 2017, pp. 406-407, 415).
The toothless blindcat and widemouth blindcat occur in a very deep
portion of the San Antonio segment of the Edwards Aquifer, where they
can likely move through the groundwater flowing through a system of
interconnected subterranean conduits (Ford and Williams 2007, pp. 103-
106, 112-114; Culver and Pipan 2009, pp. 5-8; Veni 2012, pp. 603-608;
White 2012, pp. 383-386). These caves and conduits are formed in the
rock layers of the Edwards Aquifer through dissolution by groundwater
(Livingston et al. 1936, pp. 72-73; Petitt and George 1956, p. 16;
Maclay and Small 1986, p. 61).
Due to their deep subterranean habitat, the toothless blindcat and
widemouth blindcat exhibit several stygomorphic (adaptations to
subterranean conditions) characteristics, including depigmentation,
absence of fully developed eyes, and short lateral line canals
(Lundberg 1982, pp. 77-78; Langecker and Longley 1993, pp. 978-980;
Lundberg et al. 2017, pp. 163-164). Blindcats lack scales and possess
eight barbels (whisker-like sensory organs) arranged around the snout
and mouth (Eigenmann 1919, p. 398; Hubbs and Bailey 1947, pp. 5, 10;
Lundberg 1982, p. 16; Burr et al. 2020, p. 42). The toothless blindcat
and widemouth blindcat appear to be among the smallest known catfishes,
reaching total lengths of up to 103.8 millimeters (mm) (4.1 inches
(in)) and 136.9 mm (5.4 in), respectively (Hubbs and Bailey 1947, pp.
8-10, 12-14; Suttkus 1961, pp. 62-63; Lundberg 1982, pp. 10-11;
Langecker and Longley 1993, p. 977; Burr et al. 2020, p. 26).
The toothless blindcat lacks teeth, and its jaw is thin and papery
with a funnel-like mouth positioned ventrally below the snout (Hubbs
and Bailey 1947, pp. 5, 11-12; Lundberg 1982, pp. 15-16). The widemouth
blindcat possesses well-developed teeth, a robust jaw, and a larger
mouth positioned transversely at the depressed and flat snout (Hubbs
and Bailey 1947, p. 5). From their jaw and mouth morphology, as well as
specimen stomach contents, we infer that the toothless blindcat is a
detrivore that feeds on biofilm and other organic material, whereas the
widemouth blindcat is likely an opportunistic predator capable of
taking sizeable prey (Longley and Karnei 1978a, pp. 31, 34; Lundberg et
al. 2017, pp. 160, 162).
There is documentation of toothless blindcat individuals being
expelled from eight wells and widemouth blindcat individuals from five
wells, with overlapping expulsions at two wells (Zara Environmental
2020, pp. 11-12; Diaz 2021, p. 30). Wells that have produced the
species are relatively close, with an average distance between wells of
4.5 kilometers (km) (2.8 miles (mi)) for the toothless blindcat and 6.3
km (4.0 mi) for the widemouth blindcat (Service 2022, p. 45). Given the
potential for hydrogeological connectivity, the species likely exist as
single sympatric subterranean populations. Well depth ranges from 308 m
(1,010 ft) to 582 m (1,909 ft) (Zara Environmental 2020, pp. 14-23),
making these species some of the deepest known cavefish (Trajano 2001,
p. 140; Fi[scaron]er et al. 2014, p. 976). These wells are distributed
along a southwest to northeast trending line through Bexar County,
roughly paralleling the southeastern boundary of the aquifer's artesian
zone. The artesian zone of the Edwards Aquifer is where hydraulic
pressure of groundwater forces water to the surface, where the water
escapes through springs, seeps, or wells drilled into the aquifer
(Lindgren et al. 2004, pp. 35, 39-40).
The southeastern extent of the artesian zone represents the limit
of freshwater in the Edwards Aquifer (Hovorka et al. 1995, p. 3; Sharp
and Smith 2019, pp. 151-152). Groundwater from the aquifer's artesian
zone is considered high-quality with low dissolved solids ranging from
300 to 500 milligrams/liter (mg/l) (Petitt and George 1956, p. 76;
Maclay et al. 1980, p. 8). To the southeast of the artesian zone,
dissolved solids increase and the groundwater becomes progressively
more saline (Groschen 1993, pp. 2, 7; Groschen and Buszka 1997, pp. 1-
3). The contact point where freshwater (i.e., <1,000 mg/l dissolved
solids) generally meets saline water (i.e., >1,000 mg/l) is termed the
``freshwater/saline-water interface'' (Arnow 1959, p. 40; Maclay et al.
1980, p. 10; Groschen 1993, p. 2; Groschen and Buszka 1997, pp. 1, 3).
All wells where blindcats have been expelled occur just to the
northwest of the freshwater/saline-water interface on the freshwater
side.
Neither blindcat species has ever been directly observed in its
natural subterranean habitat, but we can infer the species' needs from
their location and from the life-history of other cavefish species.
Subterranean habitat for the toothless blindcat and widemouth blindcat
appears to be centered in an area of greater aquifer permeability in
Bexar County (Maclay 1995, pp. 26-27; Hovorka et al. 1996, pp. 50, 54-
57; Hovorka et al. 2004, p. 19). Concentrated groundwater flow in this
area has likely resulted in the formation of enlarged faults,
fractures, and cavernous openings that provide suitable physical
habitat for the blindcats (Lindgren et al. 2004, pp. 16).
The area along the freshwater/saline-water interface is likely an
area of focused groundwater movement due to
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greater porosity and permeability in that area (Maclay and Small 1986,
p. 66; Hovorka et al. 1996, pp. 50, 54-57; Worthington 2003, pp. 16,
20, 23-24; Hovorka et al. 2004, pp. 19, 42; Lindgren et al. 2004, pp.
11, 15, 17-21, 26). We infer the importance of this location for these
species from the hydraulic connectivity and the existence of aquifer
food resources at great depth near this interface (Birdwell and Engel
2009, pp. 153-155; Engel and Randall 2011, pp. 313-314, 318; Hutchins
et al. 2013, pp. 254-255; Bishop et al. 2014, pp. 90-91; Hutchins et
al. 2016, pp. 1535-1539). Due to the historical absence of human-
related contamination, we also infer that the toothless blindcat and
widemouth blindcat are adapted to and require groundwater of a certain
quality from the Edwards Aquifer that is relatively free of
anthropogenic contaminants.
Longevity and reproduction of the toothless blindcat and widemouth
blindcat is not known but can be inferred from other cavefish species.
Cavefishes are generally characterized by life history traits such as
increased age at first reproduction, lower numbers of reproductively
active females, reduced numbers of eggs, slower growth rates, and
longer life spans (Poulson 1963, pp. 266, 268, 275; Trajano 1997, p.
367; Trajano 2001, pp. 152-153; Trajano and Bichuette 2007, p. 114;
Niemiller and Poulson 2010, pp. 220-227, 232-235; Secutti and Trajano
2021, p. 103). Estimated lifespans of other cavefish range from 8 to 45
years (Niemiller and Poulson 2010, p. 226; Trajano 1997, p. 367;
Trajano 2001, pp. 151-152; Trajano and Bichuette 2007, p. 114; Secutti
and Trajano 2021, p. 103).
Because the blindcats are cavefish, we assume that age at first
reproduction for the toothless blindcat and widemouth blindcat is
likely older than 2 years of age, and the age at reproductive maturity
is likely 6 years of age or older; this is older than the age at first
reproduction for surface catfish species and similar to or older than
the age of reproductive maturity for the northern cavefish (Niemiller
and Poulson 2010, p. 221). Also, like other cavefishes (Niemiller and
Poulson 2010, pp. 221-222), we assume that only a fraction (3 percent
to 13 percent) of female toothless blindcats and widemouth blindcats
produce offspring on an annual basis. Clutch size is likely comparable
to the small clutches produced by Noturus species (fewer than 200
eggs). Adult toothless blindcats and widemouth blindcats probably reach
significant ages for catfishes, with maximum ages of multiple decades
(more than 25 years). The toothless blindcat and widemouth blindcat
inhabit a subterranean system that is well-buffered from immediate
seasonal changes. However, seasonality of reproduction cannot be
dismissed, as these fish may respond to periods of high or low
groundwater flow in relation to aquifer recharge.
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.
[[Page 57050]]
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 these 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 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.
To assess the viability of the toothless blindcat and the widemouth
blindcat, 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 these 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 both individual species' life-
history needs. The next stage involved an assessment of the historical
and current condition of each species' demographics and habitat
characteristics, including an explanation of how the species arrived at
its current condition. The final stage of the SSA involved making
predictions about the species' responses to positive and negative
environmental and anthropogenic influences. Throughout all of these
stages, we used the best available information to characterize
viability as the ability of a species to sustain populations in the
wild over time which we then used to inform our regulatory decision.
The following is a summary of the key results and conclusions from
the SSA report; the full SSA report can be found at Docket No. FWS-R2-
ES-2023-0069 on https://www.regulations.gov.
Summary of Biological Status and Threats
In this discussion, we review the biological condition of the
toothless blindcat and the widemouth blindcat and their resources, and
the threats that influence these species' current and future condition,
in order to assess these species' overall viability and the risks to
that viability.
Species Needs
Adequate Population Size
Both species of blindcats are assumed to have potentially numbered
in the tens of thousands of individuals historically (Trajano 2001, pp.
145-146; Service 2022, pp. 43-44). Due to the toothless blindcat being
in a lower trophic level as a detrivore and the widemouth blindcat
being in a higher trophic level as a predator, we assume the population
of the widemouth blindcat is smaller than that of the toothless
blindcat (Trajano 2001, p. 145). Adequate population size at sufficient
density is needed for both species to access mates for reproduction and
withstand stochastic events. Mortality events in long-lived,
reproductively constrained fish populations can have prolonged impacts
on population demographics, including reduced numbers of sexually
mature fish, reduced reproductive output, and diminished recruitment of
younger individuals (Adams 1980, p. 7; Heppell et al. 2005, pp. 213-
214, 217; Graening et al. 2010, pp. 74-75; Whiterod et al. 2018, pp.
622-626). Representation among various age-classes is needed to support
recruitment of sexually mature adults to maintain adequate population
sizes (Adams 1980, pp. 2-7; Poulson 2001, pp. 354-357; Hsieh et al.
2010, pp. 167-176).
Intact and Interconnected Subterranean Void Space
The toothless blindcat and widemouth blindcat inhabit subterranean
voids of sufficient size and connectivity within the Edwards Aquifer.
The species' occurrence from multiple wells along a southwest to
northeast trending line in Bexar County suggests that the ranges of
both species might be relatively continuous. Subterranean networks of
water-filled conduits can facilitate gene flow through the water-filled
voids of aquifers (Chippindale 2009, pp. 8-9; V[ouml]r[ouml]s et al.
2018, p. 217; Corbin 2020, p. 75; Falniowski et al. 2021, pp. 4979-
4980, 4985-4986; Grego and Pe[scaron]i[cacute] 2021, pp. 68, 73-74).
Both fish species use these connected areas for dispersal, foraging,
and reproduction (Service 2022, pp. 29-37, 44-45).
Adequate Groundwater Quantity
Sufficient volumes of groundwater are needed to fill subterranean
void space and provide dispersal corridors for the species within a
narrow band of the Edwards Aquifer. The region of the aquifer these
species inhabit is an area of significant groundwater flow (Maclay and
Small 1986, p. 66; Hovorka et al. 1996, pp. 50, 54-57; Worthington
2003, pp. 16, 20, 23-24, 31-32; Hovorka et al. 2004, pp. 19, 42;
Lindgren et al. 2004, pp. 11, 15, 17-21, 26).
Suitable Water Quality
Over millions of years, both the toothless blindcat and widemouth
blindcat have evolved to very deep aquifer conditions, including the
water quality at these depths. Thus, they likely need water quality
that matches natural aquifer conditions, including a pH of 7-8, a
consistent temperature around 28 degrees Celsius ([deg]C) (82 degrees
Fahrenheit ([deg]F)), specific conductivity between 465-482
microsiemens per centimeter ([micro]S/cm), and relatively free of
contaminants (Karnei 1978, pp. 115-116; Service 2022, pp. 37-41).
Chemolithoautotrophic Food Web
Subterranean systems at great depths and without direct connections
to the surface are often isolated from surface sources of organic
matter (Akob and K[uuml]sel 2011, p. 3534; Hubalek et al. 2016, pp.
2447-2448; It[auml]vaara et al. 2016, pp. 4, 6-8). Instead, food webs
in these settings may be based on microbial production of organic
carbon from inorganic materials in a process termed
chemolithoautotrophy (Engel 2007, pp. 187-188). Microbes involved in
chemolithoautotrophy include a wide range of bacteria and fungi adapted
to
[[Page 57051]]
the extreme conditions (such as high pressure and high salinity) of the
deep subsurface (Amend and Teske 2005, pp. 145-147; Engel 2007, p. 188;
Akob and K[uuml]sel 2011, pp. 3534, 3236; It[auml]vaara et al. 2016,
pp. 3-4, 20-22). The toothless blindcat is believed to be a detrivore
that feeds on bacterial biofilms. The widemouth blindcat is
hypothesized to be a predator that feeds on groundwater invertebrates
and potentially suitably sized toothless blindcats. For both species to
persist, they need a functional chemolithoautotrophic food web in an
undegraded condition. Because groundwater in the Edwards Aquifer
originates from precipitation and stream runoff, infusion of surface-
borne nutrients to toothless blindcat and widemouth blindcat habitat
cannot be discounted and may play some role in the deep aquifer food
web. However, no accounts detailing surface-borne nutrient presence at
great aquifer depth have been published to date.
Summary of Threats
We reviewed the potential threats that could be currently affecting
the toothless blindcat and the widemouth blindcat. In this proposed
rule, we will discuss only those threats in detail that could
meaningfully impact the status of either species (a more in-depth
analysis of all potential threats can be found in the SSA report
(Service 2022, pp. 54-61, 87-95). We conducted a thorough analysis of
threats to groundwater quality in terms of degradation due to
pollutants and other contaminants and threats to groundwater quantity
in the form of pumping and climate change. We found that while these
threats may impact the species, they are not likely to have effects at
the population or species level. For example, groundwater contamination
has the potential to impact the toothless blindcat and widemouth
blindcat (Service 2022, pp. 60-61). However, because of the depth of
the species' habitat and the thick impermeable rock layer covering it,
groundwater contamination is not a primary threat for the status of the
toothless blindcat or the widemouth blindcat. Similarly, because of the
depth of the species' habitat, groundwater quantity to support habitat
for the fishes has not experienced change from historical conditions.
Aquifer water levels where the blindcats reside show no evidence of
long-term decline, even at times of prolonged drought and unregulated
pumping (Maclay 1995, pp. 48, 52; Lindgren et al. 2004, 40-41, 45). In
addition, management of groundwater withdrawals from the San Antonio
segment has been in place since the late 1990s (National Research
Council 2015, pp. 24-27, 29, 32-36; National Academies of Sciences,
Engineering, and Medicine 2018, pp. 7-8, 109, 152; Hardberger 2019, pp.
193-194; Payne et al. 2019, p. 199) and pumped volumes have decreased
since 2008 (Service 2022, pp. 80-81). Flow protection measures are in
place that principally protect the two largest spring systems in the
region (Comal Spring and San Marcos Spring systems), but those measures
also benefit water levels deeper in the aquifer. We also note that,
while competition with exotic species was identified in our 90-day
finding (74 FR 66866; December 16, 2009) as a potential threat, a
thorough review of the literature and consultation with experts
revealed no evidence of exotic species competing with or otherwise
impacting either species. The primary threat affecting the status of
the toothless blindcat and the widemouth blindcat is mortality through
groundwater well uptake (Factor E).
Groundwater Wells
Prior to well drilling and extraction of groundwater from the
Edwards Aquifer in the late 19th century, the toothless blindcat and
widemouth blindcat were unaffected by anthropogenic surface activities
given the substantial depth of their habitat and the layers of
impermeable rock that separated that habitat from the surface.
Extraction of groundwater from wells represented a new and nearly
constant stressor impacting both species' populations. Well mortality
is currently the most direct and observable anthropogenic agent of
mortality for both species. No toothless blindcat or widemouth blindcat
expelled from groundwater wells has survived for any extended period,
and many specimens are ejected mangled and dead due to battering as
they are forced to the surface.
In Bexar County, the drilling of wells to meet public supply and
irrigation demands began in the late 1880s (Livingston et al. 1936, p.
87; Petitt and George 1956, p. 44). The existence of the toothless
blindcat and widemouth blindcat was only documented through individual
fish expelled from groundwater wells in the early 20th century
(Eigenmann 1919, pp. 397, 399-400; Hubbs and Bailey 1947, pp. 1, 4-11).
More than 1,500 wells were drilled in Bexar County by 1953, with 250
wells being large capacity (i.e., 25-76 centimeters (cm) (10-30 in) in
diameter) (Petitt and George 1956, p. 44; Maclay 1995, p. 43), with
additional large capacity wells drilled during the 1950s across the
City of San Antonio and Bexar County (Petitt and George 1956, p. 47;
Arnow 1959, pp. 24, 29). Until 1996, groundwater extraction in Bexar
County was completely unregulated, with no restrictions on well
capacity, volumes of water discharged, or groundwater waste (Miller
2005, pp. 172-173; Gulley 2015, p. 2; Mace 2019, p. 208). From 1939 to
2000, annual groundwater withdrawals increased by an average of
5,550,660 cubic meters (m\3\) (4,500 acre-feet (ac-ft)) per year
(Lindgren et al. 2004, pp. 35-36). As of September 28, 2022, the Texas
Water Development Board (2022, unpaginated) lists 307 active wells, at
depths of more than 300 m (984 ft), that access the artesian zone of
the Edwards Aquifer in Bexar County.
The additive effect of anthropogenic mortality on cavefishes has
been studied for only a few taxa. Cavefish exhibit delayed maturity,
reduced fecundity, low mortality, and longer lifespans (Pianka 1970, p.
592; Bichuette and Trajano 2021, p. 2). Because cavefish have few
offspring, the loss of individuals can have a substantial effect on the
population; any fish that is killed does not survive to reproduce and
contribute individuals to the population in the future. The Ozark
cavefish (Amblyopsis rosae) is one example of the long-lasting impact
of anthropogenic mortality. After the impact of human threats,
populations of this species skewed towards older individuals with few
younger fish present (Service 1989, p. 7; Graening et al. 2010, pp. 74-
75). It was not until the 2000s, after a multi-decade period of
recovery following the legal prohibition against collection, that a
larger proportion of younger Ozark cavefish began to appear in
populations, indicating the cessation of adult capture and the
successful recruitment of juvenile fish (Graening et al. 2010, pp. 74-
75).
Several deep-sea fishes also have similar life-history traits as
cavefishes, including production of fewer and larger eggs, delayed
sexual maturity, extended longevities, and roles as top predators in
their respective systems (Poulson 2001, pp. 350, 357). Deep-sea fishes
have been better studied regarding their response to anthropogenic
mortality in the form of fishing (Adams 1980, pp. 1-2). Taxa such as
orange roughy (Hoplostethus atlanticus), Patagonian toothfish
(Dissostichus eleginoides), and other deep-sea species are very
sensitive to overfishing (Adams 1980, pp. 4-5; Heppell et al. 2005, pp.
211-212). Fishing operations often target adult size classes that are
slow to recruit into populations, which can lead to decreased egg
production (Heppell et al. 2005, pp. 213-214, 217). As a result, deep-
sea fish populations are slow to recover (i.e., multiple decades) from
[[Page 57052]]
harvesting pressure due to reduced reproductive capacity (Adams 1980,
p. 7; Whiterod et al. 2018, pp. 622-626).
The toothless blindcat and widemouth blindcat are among the oldest
cavefishes in North America (Arce-H et al. 2017, pp. 421, 425). Both
species, which are some of the deepest dwelling among known cavefishes,
evolved over millions of years to inhabit very deep aquifer conditions
(Trajano 2001, p. 140; Fi[scaron]er et al. 2014, p. 976). The
environmental stressors that typically affect and influence shallow
subterranean systems (such as flooding, drying of cave passages/
streams, and reduced surface nutrient input) are presumed to not
operate, or are muted, at the depths where the blindcats occur. The
deep artesian zone of the Edwards Aquifer provides a stable nutrient
source (chemolithoautotrophy), consistent water quality (decades old
groundwater), and very attenuated responses to climatic changes
(temperature changes) on the surface. Given their long evolutionary
history, the toothless blindcat and widemouth blindcat have life
history traits that make them comparable to, if not more sensitive
than, most other cavefishes in their response to increased loss of
individuals from their populations.
While cavefish collection and deep-sea fishing removes larger size-
class fish, loss of toothless blindcats and widemouth blindcats to
groundwater pumping is plausibly size-indiscriminate. Wells extracting
groundwater have the potential to remove blindcats at all life stages
given that motile life stages move through water-saturated voids and
are thus likely pelagic. Blindcats observed or collected from
groundwater wells have been juveniles to adults. No eggs or smaller
size classes (e.g., larvae or fry) of either species have been reported
to date. It is unlikely that eggs or larvae are not expelled from wells
along with juveniles and adults. Rather, as larger individuals of both
species are often severely mangled as they are forced up wells, it is
probable that similarly transported eggs and larvae are physically
destroyed and not visually discernable.
Additionally, unlike discrete collection and fishing events,
groundwater pumping operates over much longer and sustained time frames
given demands for groundwater. On an annual basis, wells may operate
for several continuous months during the growing season for
agricultural irrigation or nearly year-round for industrial and public
water supply. The operational lifespan of many Bexar County wells is
several decades long (e.g., more than 60 years; Service 2022, pp. 70-
80). Consequently, there has likely been very limited opportunity for
cessation of this stressor where wells intercept toothless blindcat and
widemouth blindcat habitat. In essence, groundwater wells may
constitute near-permanent population sinks that can result in the
mortality of most blindcats at all life stages. Loss of immature and
adult individuals would constrain population growth through reductions
in egg production and recruitment of mature adults. The impact of
groundwater well mortality on toothless blindcat and widemouth blindcat
populations could be substantial, with the potential to expel
substantial numbers of toothless blindcats and widemouth blindcats over
their operational lifespans (see Current Condition, below; Longley and
Karnei 1978a, p. 36; Longley and Karnei 1978b, p. 39; Service 2022, pp.
74-79).
We note that, by using the SSA framework 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 these species. To assess the current and future condition of
these 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
In the early 1990s, federal litigation (Sierra Club v. Secretary of
the Interior, No. MO-91-CA-069, U.S. District Court for the Western
District of Texas) directed the Service to make determinations
regarding minimum spring flows and aquifer levels necessary to support
listed species occurring in the Comal Spring and San Marcos Spring
systems. The Service produced a recovery plan with that guidance in
1996 (Service 1996, entire). Another outcome of litigation was the
creation, in 1993, of the Edwards Aquifer Authority by the State of
Texas to manage groundwater withdrawals (by nonexempt wells) from the
San Antonio segment of the Edwards Aquifer (National Research Council
2015, pp. 24-26; Hardberger 2019, pp. 193-194; Payne et al. 2019, p.
199). The regulatory area of the Edwards Aquifer Authority includes all
or a portion of Bexar, Comal, Hays, Medina, and Uvalde Counties.
The Edwards Aquifer Authority developed a habitat conservation
plan, approved by the Service in 2013, which provides measures to
minimize and mitigate take of the nine listed species related to
covered activities (National Research Council 2015, pp. 27, 29, 32-36;
RECON Environmental, Inc. 2021, pp. 3-55-3-67). Covered activities
include groundwater withdrawals for drinking water supplies and
irrigation as well as recreational activities (National Research
Council 2015, pp. 32-36; RECON Environmental, Inc. 2021, pp. 2-1-2-16).
The voluntary minimization and mitigation measures of the plan are
based on maintaining sufficient minimum flows at Comal Spring and San
Marcos Spring to sustain listed species during a reoccurrence of
prolonged drought conditions (National Research Council 2015, pp. 32-
36; National Academies of Sciences, Engineering, and Medicine 2018, pp.
67-68; Service 2022, p. 64). A review of the Edwards Aquifer Habitat
Conservation Plan suggests that flow protection measures, including
groundwater modeling efforts, appear to be effective in meeting flow
requirements of covered species (National Academies of Sciences,
Engineering, and Medicine 2018, pp. 7-8, 109, 152). Additionally,
volumes of groundwater pumped from the San Antonio segment of the
Edwards Aquifer have decreased since 2008 (Service 2022, pp. 64-65).
The toothless blindcat and widemouth blindcat are not included in
the habitat conservation plan because the plan's actions are most
applicable to spring-dwelling species that inhabit upper portions of
the Edwards Aquifer (RECON Environmental, Inc., pp. 1-9). However,
protection of sustained flow at the Comal Spring and San Marcos Spring
systems does provide overarching protection for species that inhabit
deep portions of the San Antonio segment. Persistence of surface
discharge at those spring systems suggests that deeper levels of the
aquifer have not been appreciably reduced and remain water-saturated
(Maclay 1995, pp. 48, 52; Lindgren et al. 2004, 40-41, 45).
An additional conservation measure is land protection efforts by
the City of San Antonio's Edwards Aquifer Protection Program (Stone and
Schindel 2002, pp. 38-39; Carnett 2022, unpaginated). In 2000, San
Antonio passed Proposition 3, an initiative to fund the acquisition
(fee-simple and conservation easements) of open space
[[Page 57053]]
to protect the contributing and recharge zones of the aquifer in Bexar
County (Romero 2018, p. 2). That program was reapproved in 2005, 2010,
and 2015, with additional funds to acquire open space (Reilly and
Carter 2018, pp. 1-3-1-5). The effort was later expanded to acquire
lands in Medina and Uvalde Counties that contain larger portions of the
Edwards Aquifer's contributing and recharge zones (Romero 2018, pp. 5-
6, 8). The dedicated sales tax expired in 2021, with 97,124 hectares
(240,000 acres) acquired under the Edwards Aquifer Protection Program
(Carnett 2022, unpaginated). The City of San Antonio recently approved
an alternative funding stream to support land acquisitions through the
commitment of $100 million over 10 years (Carnett 2022, unpaginated).
Protection of open space has the potential to reduce the impacts of
development (for example, run-off from impervious cover, fertilizer
applications, and wastewater) and maintain aquifer recharge (Reilly and
Carter 2018, pp. 3-2, 3-6; Romero 2018, pp. 5-6).
Several other entities also have measures to protect groundwater
from contamination. These entities include the Edwards Aquifer
Authority's Aboveground Storage Tank Program, Agricultural Secondary
Containment Assistance Program, and Abandoned Well Program, among
others (Edwards Aquifer Authority 2022, unpaginated). The San Antonio
Water System implemented several water quality protection measures
including development regulations (City of San Antonio Code of
Ordinances, chapter 34, article VI, division 6, Aquifer Protection
Ordinance No. 81491) for properties over the contributing and recharge
zones, review of building permits and master development plans,
regulation of underground storage tanks, and commercial/industrial
compliance (San Antonio Water System 2022, unpaginated).
Current Condition
To assess the current conditions of the toothless blindcat and
widemouth blindcat, we established analysis units immediately around
well sites with documented records of the toothless blindcat or
widemouth blindcat (``immediate area analysis units''), as well as a
larger area encompassing these smaller units (``potential area of
occurrence'') in order to assess threats to the fishes in a more
spatially extensive area with a potentially contiguous subterranean
system of voids within the aquifer. Neither of these units define
populations but rather geographic areas we presume are areas of
potential occupancy or areas that are important to or could influence
both species' survival. The SSA report further details the methodology
and rationale for creating these units (Service 2022, pp. 67-68).
Eight wells that historically produced toothless blindcat (six
wells) and widemouth blindcat (four wells; two of which overlap with
the toothless blindcat wells) have either been capped, plugged, or
destroyed. Three wells that produced toothless blindcats (one of which
also produced widemouth blindcats) are presumed to still operate, as we
do not have access to the wells to confirm, nor do we have evidence to
the contrary. Including these three wells, the immediate area analysis
units contain a combined total of 27 active groundwater wells. Most of
these wells are for agricultural irrigation or public water supply. The
average age of these wells is 68 years, with the oldest well drilled in
1933 and the latest in 1985. Seventeen wells in the analysis units have
been abandoned, plugged, or destroyed, including historical blindcat
wells. Besides the documented blindcat wells in the analysis units,
only 1 of the 24 active wells has ever been sampled for blindcats due
to lack of access.
In the larger potential area of occurrence, a total of 82 active
groundwater wells are established, including the active blindcat wells.
Most of these wells are used for irrigation, public water supply, and
industrial purposes. Primary water uses of the remaining wells are for
aquaculture, domestic purposes, and livestock. Average age of active
wells is 66 years, with the earliest wells drilled in 1915 and most
recent in 2020. There are 36 abandoned, plugged, or destroyed wells in
the potential area of occurrence. The four wells that have been sampled
in this area showed no evidence of either blindcat species (Karnei
1978, pp. 68-70; Zara Environmental 2010, p. 68; 2020, p. 10).
Well Mortality Estimates
Researchers who have sampled groundwater wells for the toothless
blindcat and widemouth blindcat have developed catch-per-unit-effort
estimates for their sampling efforts (Longley and Karnei 1978a, pp. 35-
36; 1978b, pp. 36, 38-40; Zara Environmental 2020, pp. 23-27). Catch
per unit effort was expressed as volume of groundwater exiting a well
to produce one individual of either species. Available estimates were
based on surveys of toothless blindcat and widemouth blindcat
populations that had already been subjected to several decades of
unregulated groundwater extraction. The status of both blindcat
species' populations prior to groundwater pumping is unknown, although
it is known that both species experienced mortality once wells were
established. It is plausible that, at the time of survey efforts (late
1970s and 2008 to 2014), toothless blindcat and widemouth blindcat
population resiliency had already been diminished to some extent from
past well mortality.
We assume that a higher catch per unit effort at a well, or lower
volume of groundwater required to produce a single individual, may
reflect larger blindcat populations. The highest catch per unit effort
for both the toothless blindcat and widemouth blindcat comes from
estimates for the Artesia Pump Station Well, with one toothless
blindcat caught with every 65,000 m\3\ (53 ac-ft) of groundwater and
one widemouth blindcat caught with every 129,515 m\3\ (105 ac-ft) of
groundwater (see Table 1 below; Longley and Karnei 1978a, pp. 35-36;
1978b, pp. 36, 38-40).
We apply those estimates of catch per unit effort to estimate
blindcat well mortality. These estimates of blindcat well mortality do
not account for variability in distribution and extent of suitable
blindcat habitat, fish abundances by site, well size and discharge
capacity, periods of discharge (intermittent or constant), location of
well casing relative to potential habitat, and reporting of discharged
volumes. Complete data on those and other variables are not available.
Estimates of well mortality also only apply to assumed losses of
larger juvenile and adult fishes. Catch per unit effort has never been
developed for larvae and very small juveniles. The following estimates
of well mortality will therefore be underestimates, as no data exist on
loss of those life stages. Research on other cavefishes and deep-sea
fishes with similar life history traits suggests that sustained loss of
individuals, especially sexually mature fish, can result in reduced
population sizes and changes in demographic structure.
To estimate average annual mortality, we examined pumped
groundwater volume data available for 51 wells in the potential area of
occurrence between the years of 2010 to 2017 (Edwards Aquifer Authority
2021, unpaginated). Using the annual average volume of groundwater
pumped from all 51 wells, 10,401,411 m\3\ (8,433 ac-ft), multiplied by
the estimated catch per unit effort, 159 toothless blindcats and 80
widemouth blindcats may have been expelled from wells annually. This is
likely an underestimate of losses, as it does not
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include losses of other immature stages, such as larvae or fry. These
numbers could be higher still considering the remaining active wells
for which pumped data are not available. Abandoned and plugged wells
would have also contributed to past mortality during their operational
lifespans.
Most wells in the potential area of occurrence have been in
operation for multiple decades (average age of 66 years). To illustrate
the potential total loss of blindcats to wells operated over several
decades, we assigned the average annual volume discharged (calculated
from three wells from 2010 to 2017) to all wells for all years between
the completion of a well to 2021 (the latest year for which data were
available). As we assume the blindcats have long lifespans, the
likelihood that individuals will encounter the capture zone of an
active groundwater well increases over time. Wells operating over
several decades, and discharging relatively moderate volumes of
groundwater, could result in the loss of over a thousand toothless
blindcats and several hundred widemouth blindcats per individual well
(see Table 1 below, Service 2022, p. 77).
Table 1--Estimated Potential Loss of Toothless Blindcats and Widemouth Blindcats to Groundwater Wells
----------------------------------------------------------------------------------------------------------------
Total
estimated
number of
Individuals individuals
Species Volume to produce one individual lost per year lost in 51
per well wells within
potential area
of occurrence
----------------------------------------------------------------------------------------------------------------
Toothless blindcat............................ 65,000 m \3\.................... 159 535,194
(53 ac-ft)......................
Widemouth blindcat............................ 129,515 m \3\................... 80 269,280
(105 ac-ft).....................
----------------------------------------------------------------------------------------------------------------
Estimates are for the wells within the potential area of occurrence with water volume data (n = 51), given
operational lifespan (average age of 66 years), and catch per unit effort reported for Artesia Pump Station
Well (Longley and Karnei 1978a, pp. 35-36; 1978b, pp. 36, 38-40).
In addition to the estimated loss from moderate capacity wells,
greater capacity wells have been drilled in or near the potential area
of occurrence, but data are lacking regarding their historical
discharge volumes. The following mortality estimates for larger
capacity wells further illustrate the potential impact high volume
wells could have on blindcat numbers over decades of operation.
In 1941, San Antonio Public Service Company Well 4 was drilled to a
depth of 314 m (1,032 ft) (Livingston 1942, p. 1; Petitt and George
1956, p. 47). That well is approximately 2.4 km (1.5 mi) to the
northeast of Bexar Metropolitan Water District Well (a widemouth
blindcat locality) and 7.5 km (4.7 mi) to the southwest of the Artesia
Pump Station Well (a toothless blindcat and widemouth blindcat
locality). It is conceivable that blindcat habitat extended to that
location, although the well has never been sampled for either fish
species.
Flow at San Antonio Public Service Company Well 4 has been recorded
at 1.05 m \3\ per second (m \3\/sec) (37 cubic feet per second (ft \3\/
sec)) (Livingston 1942, pp. 3-4). Flow at that rate over 12 months
would result in discharge of 33,134,800 m \3\ (26,863 ac-ft) of
groundwater and potentially 507 toothless and/or 266 widemouth
blindcats per year. If that well operated at that capacity over its 81-
year operational lifespan, 41,055 toothless blindcats and 20,723
widemouth blindcats could have potentially been expelled from the well.
Well 4 is still in operation based on Texas Water Development Board
records.
In 1891, the first of a series of 20 to 30 cm (8 to 12 in) diameter
wells were drilled in what would become the Market Street Pump Station
(Ewing 2000, pp. 13, 15, 22; Eckhardt 2016, unpaginated). The 1891 well
was 271 m (890 ft) deep and produced 4,144,499 m \3\ (3,360 ac-ft) of
groundwater per year (Ewing 2000, pp. 13, 22). Three additional wells
were drilled in 1894, one well with an annual pumped capacity of
7,598,248 m \3\ (6,160 ac-ft) and two wells at 4,144,499 m \3\ (3,360
ac-ft) (Ewing 2000, p. 22). The total annual pumping capacity of these
four wells would have been 20,031,745 m \3\ (16,240 ac-ft). If
blindcats entered the capture zones of these wells, 305 toothless
blindcats and 155 widemouth blindcats could have been discharged per
year.
By 1924, the Market Street pump station had 12 wells with a
combined capacity of pumping 59,404,485 m \3\ (48,160 ac-ft) per year
(Ewing 2000, p. 15). The pump station's 1924 capacity of 59,404,485 m
\3\ (48,160 ac-ft) could have resulted in the discharge of 9,086
toothless blindcats and 4,587 widemouth blindcats over a 10-year
period. At that same rate, from 1924 to 2022, 89,051 toothless
blindcats and 44,491 widemouth blindcats would have been expelled from
wells over that 98-year period. The Market Street pump station is still
in operation today with several large capacity wells (Eckhardt 2016,
unpaginated).
While these scenarios of blindcat losses due to wells are
hypothetical estimates, they provide insight into the scale of well
mortality for the toothless blindcat and widemouth blindcat. We know
that both species are ejected by groundwater wells and die. It is
evident that wells extracting water from the artesian zone remove
blindcats and that large capacity wells have the potential to expel
thousands of individuals over a well's operational lifespan. However,
the location and depth of wells influence their ability to affect
blindcat populations; only certain wells will intercept areas occupied
by toothless and/or widemouth blindcats. That said, very productive
groundwater wells likely intercept larger water-filled voids that would
serve as blindcat habitat (Maclay 1995, p. 43).
Conclusions
The most significant stressor to populations of the toothless and
widemouth blindcats is mortality due to groundwater pumping.
Individuals of both species are forced up artesian and pumped wells
where they are physically damaged and killed. Wells with long
operational lifespans could have resulted in the deaths of thousands to
tens of thousands of individuals. All life stages of the blindcats are
expected to experience mortality due to the action of groundwater
wells. The greatest loss of
[[Page 57055]]
blindcats potentially occurred from the early 1940s into the early
1960s, when the largest number of groundwater wells were drilled in the
potential area of occurrence within the Edwards Aquifer.
The widemouth blindcat has not been observed from any well since
1984. Due to groundwater pumping, the species may have declined to
undetectable numbers (Ferretti et al. 2008, pp. 960-962) or become
functionally extinct (i.e., permanent reproductive failure prior to
true extinction; Ricciardi et al. 1998, p. 617; Delord 2007, p. 659;
Bull et al. 2009, p. 419; Roberts et al. 2017, p. 1193). Toothless
blindcats, however, have been taken from the Aldridge 209 Well most
years between 2008 and 2013 and from 2020 to 2022. The species appears
to be persisting in this area but seemingly in low numbers. Between
2008 and 2013, material potentially representing 13 individual
toothless blindcats was taken from the Aldridge 209 Well (Zara
Environmental 2020, pp. 11, 18-20). Between 2021 and 2022, material
potentially comprising four toothless blindcats was taken from the same
well (Diaz 2021, p. 29). Whether abundance of the species at that site
has declined over the well's 67-year operational lifespan is unknown.
We assume that numbers of the toothless blindcats at the Aldridge 209
Well are likely lower than prior to 1955, when the well was first
drilled. The next most recent records for the toothless blindcat are at
Tschirhart Well in 2010. The status of both species at other wells is
unknown, as they remain unsampled since the late 1970s to 1980s due to
lack of sampling access.
While pumping has resulted in the directly mortality of both
species, groundwater quantity to support habitat for the fishes has not
experienced change from historical conditions. In contrast to surface
aquifer levels, which occasionally decline, the exceedingly deep
aquifer water levels where the fishes reside show no evidence of long-
term decline, even at times of prolonged drought and unregulated
pumping (Maclay 1995, pp. 48, 52; Lindgren et al. 2004, 40-41, 45). In
addition, management of groundwater withdrawals from the San Antonio
segment has been in place since the late 1990s (Service 2022, pp. 62-
66) and pumped volumes have decreased since 2008 (Service 2022, pp. 64-
65). Flow protection measures are in place that principally protect the
Comal Spring and San Marcos Spring systems, but those measures also
benefit water levels deeper in the aquifer. Groundwater contamination
does not appear to have been a widespread or prevalent stressor for
either species. In terms of drinking water standards, contaminants in
the San Antonio segment occur in relatively low concentrations. The
presence of contaminants also decreases with depth in the aquifer where
older water is less affected by contamination. Complete analyses of the
impact of the threats of groundwater quantity, climate change, and
contamination on the toothless blindcat and the widemouth blindcat can
be found in the SSA report (Service 2022, pp. 81-85).
Based on available information, we expect that the resiliency of
both species' populations has been reduced from pre-1950 levels, the
period of new groundwater well establishment in the analysis unit.
Although populations of the toothless blindcat and widemouth blindcat
have been postulated as large (Longley and Karnei 1978a, p. 36; 1978b,
p. 39; Trajano 2001, pp. 145-146), the extensive estimated mortality
from groundwater wells has likely taken a toll on those potential
numbers. Additionally, because the toothless blindcat and the widemouth
blindcat exist as single sympatric subterranean populations, both
species effectively lack redundancy and have limited representation.
This places the toothless and widemouth blindcats at greater risk from
stochastic events and anthropogenic stressors, such as groundwater well
mortality. Well mortality has likely reduced the abundance of both
blindcats. Furthermore, the life history traits of both species suggest
that sustained loss of individuals, especially sexually mature fish,
can result in reduced population sizes and changes in demographic
structure in the form of lower numbers of sexually mature fish, reduced
reproductive output, and diminished recruitment of younger individuals.
Future Condition
As part of the SSA, we evaluated the future conditions of the
toothless blindcat and widemouth blindcat by examining the most
plausible future projections for human population growth, groundwater
demands, and climate change. Our projections show ongoing well
mortality through groundwater pumping, but no significant change to
toothless blindcat and widemouth blindcat habitat due to groundwater
quality and quantity (Service 2022, pp. 81-86). Because we determined
that the current conditions of both species are consistent with an
endangered species (see Determination of the Toothless Blindcat's and
Widemouth Blindcat's Status, below), we are not presenting the results
of the future scenarios in this proposed rule. Please refer to the SSA
report (Service 2022, pp. 86-95) for the full analysis of future
scenarios.
Determination of the Toothless Blindcat's and Widemouth Blindcat'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 Their Ranges
We find that mortality resulting from the pumping of groundwater
wells (Factor E) is the primary threat to both species. The species
occupy a limited range, and populations of both species have likely
been severely reduced since the introduction of groundwater wells in
the late 19th to early 20th century. There are currently 82 active
groundwater wells in the potential area of occurrence (Service 2022, p.
72). No toothless blindcat or widemouth blindcat expelled from
groundwater wells has survived for any extended period, and many
specimens are ejected mangled and dead due to battering as they are
forced to the surface. Discharge and sampling data indicate an
individual well operating over several decades (that is, since the
1950s), and discharging relatively moderate volumes of groundwater
could conservatively result in losses of over a thousand toothless
blindcats and several hundred widemouth blindcats.
These losses of individual fish to groundwater wells over time
suggest that both species were, and will continue to be, impacted from
actively pumped wells. Although population sizes for the toothless
blindcat and widemouth blindcat may have historically been large, we
project that
[[Page 57056]]
thousands to tens of thousands of fish have been lost to groundwater
wells since the early 1900s, and that the resiliency of both species'
populations has been reduced. Both the toothless blindcat and the
widemouth blindcat are long-lived and pelagic, and thus more likely to
encounter a well over their lifespan and be captured by well uptake.
These species have life-history traits that limit reproductive capacity
and recruitment, as documented in other cavefish species. These same
traits make the blindcats more susceptible to long-lasting population
impacts from well mortality losses.
The widemouth blindcat has not been observed at a well since the
mid-1980s, and toothless blindcat has only been expelled from a single
groundwater well multiple times between 2008 and 2013 and from 2020 to
2022. The toothless blindcat thus appears to be persisting at this
location in low numbers. Well mortality has likely reduced the
abundances of both blindcats along with effects on demographic
structure in the form of lower numbers of sexually mature fish, reduced
reproductive output, and diminished recruitment of younger individuals.
Given these impacts and the limited range of both species, it is
unlikely that even relatively robust populations of the toothless
blindcat and widemouth blindcat could indefinitely sustain continued
losses from well mortality. Both species have limited redundancy and
representation, making the loss of resiliency from well mortality
particularly detrimental.
After evaluating threats to the species and assessing the
cumulative effect of the threats under the Act's section 4(a)(1)
factors, we conclude that both species have experienced and continue to
experience the deleterious impacts of well mortality to such an extent
that both species are currently in danger of extinction, rather than at
some point in the foreseeable future. Therefore, both species meet the
Act's definition of an endangered species rather than that of a
threatened species. Thus, after assessing the best available
information, we determine that both the toothless blindcat and the
widemouth blindcat are in danger of extinction throughout all of their
ranges.
Status Throughout a Significant Portion of Their Ranges
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 toothless blindcat and widemouth
blindcat are in danger of extinction throughout all of their ranges and
accordingly did not undertake an analysis of any significant portion of
their ranges. Because the toothless blindcat and widemouth blindcat
warrant listing as endangered throughout all of their ranges, 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 both the toothless blindcat and widemouth
blindcat meet the Act's definition of an endangered species. Therefore,
we propose to list both the toothless blindcat and the widemouth
blindcat as 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 Austin 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 ranges 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 these species are 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
[[Page 57057]]
academic community, and nongovernmental organizations. In addition,
pursuant to section 6 of the Act, the State of Texas would be eligible
for Federal funds to implement management actions that promote the
protection or recovery of the toothless blindcat and widemouth
blindcat. 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 toothless blindcat and widemouth blindcat are only
proposed for listing under the Act at this time, please let us know if
you are interested in participating in recovery efforts for these
species. Additionally, we invite you to submit any new information on
these 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 consultation is required (see 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 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 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 toothless blindcat and
the widemouth blindcat that may be subject to conference and
consultation procedures under section 7 are land management or other
landscape-altering activities on Federal lands administered by the U.S.
Department of Agriculture 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, above)
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 will
not be considered likely to result in violation of section 9 of the
Act. To the extent possible, activities that will be considered likely
to result in violation will 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 or would not be 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., any person may take endangered wildlife in defense of his
own life or the lives of others). As discussed above, certain
activities that are prohibited under section 9 may be permitted under
section 10 of the Act. Questions regarding whether specific activities
would constitute a violation of section 9 of the Act should be directed
to the Austin 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
(a) Essential to the conservation of the species, and
[[Page 57058]]
(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, or
other species conservation planning efforts if new information
available at the time of those planning efforts calls for a different
outcome.
Prudency Determination
Section 4(a)(3) of the Act, as amended, and implementing
regulations (50 CFR 424.12) require that, to the maximum extent prudent
and determinable, the Secretary shall designate critical habitat at the
time the species is determined to be an endangered or threatened
species. Our regulations (50 CFR 424.12(a)(1)) state that the Secretary
may, but is not required to, determine that a
[[Page 57059]]
designation would not be prudent in the following circumstances:
(i) The species is threatened by taking or other human activity and
identification of critical habitat can be expected to increase the
degree of such threat to the species;
(ii) The present or threatened destruction, modification, or
curtailment of a species' habitat or range is not a threat to the
species, or threats to the species' habitat stem solely from causes
that cannot be addressed through management actions resulting from
consultations under section 7(a)(2) of the Act;
(iii) Areas within the jurisdiction of the United States provide no
more than negligible conservation value, if any, for a species
occurring primarily outside the jurisdiction of the United States;
(iv) No areas meet the definition of critical habitat; or
(v) The Secretary otherwise determines that designation of critical
habitat would not be prudent based on the best scientific data
available.
As discussed above, there are no significant habitat-based threats
that currently, or would in the future, limit habitat for the toothless
blindcat and the widemouth blindcat. The present or threatened
destruction, modification, or curtailment of the blindcats' habitat or
range is not a threat to the species. In light of the particular
circumstances of these two species, we have determined that designation
of critical habitat is not prudent. We reach this conclusion largely
because of the nature of the main threat for these species: direct
mortality resulting from groundwater well pumping (Factor E). The wells
constructed in these blindcats' habitat are not affecting the species
through habitat destruction or modification; instead, it is the
capture, entrainment, and death of individuals due to the pumping of
groundwater wells that is a threat to the species. Designation of
critical habitat would not provide any additional protective measures
or benefits that address this specific threat. In addition, the
designation of critical habitat would not provide otherwise unavailable
information to guide conservation efforts for these species. Therefore,
a designation of critical habitat would not be advantageous for these
species.
Since we have determined that the present or threatened
destruction, modification, or curtailment of both species' habitat or
range is not a threat to the toothless blindcat and the widemouth
blindcat, in accordance with 50 CFR 424.12(a)(1), we determine that
designation of critical habitat is not prudent for the toothless
blindcat and the widemouth blindcat.
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.
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 Secretary's Order
3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal
Trust Responsibilities, and the Endangered Species Act), we readily
acknowledge our responsibilities to work directly with Tribes in
developing programs for healthy ecosystems, to acknowledge that Tribal
lands are not subject to the same controls as Federal public lands, to
remain sensitive to Indian culture, and to make information available
to Tribes. No Tribal lands were identified within the range of the
toothless blindcat or widemouth blindcat.
References Cited
A complete list of references cited in this proposed rule is
available on the internet at https://www.regulations.gov and upon
request from the Austin 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 Austin
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 entries for ``Blindcat, toothless'' and
``Blindcat, widemouth'' in alphabetical order under FISHES to read as
follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
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Listing citations and
Common name Scientific name Where listed Status applicable rules
----------------------------------------------------------------------------------------------------------------
* * * * * * *
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Fishes
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[[Page 57060]]
* * * * * * *
Blindcat, toothless............ Trogloglanis Wherever found.... E [Federal Register
pattersoni. citation when
published as a final
rule].
Blindcat, widemouth............ Satan eurystomus.. Wherever found.... E [Federal Register
citation when
published as a final
rule].
* * * * * * *
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Wendi Weber,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-17667 Filed 8-21-23; 8:45 am]
BILLING CODE 4333-15-P