[Federal Register Volume 88, Number 122 (Tuesday, June 27, 2023)]
[Rules and Regulations]
[Pages 41724-41771]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-13461]



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Vol. 88

Tuesday,

No. 122

June 27, 2023

Part II





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





Endangered and Threatened Wildlife and Plants; Threatened Species 
Status With Section 4(d) Rule for Western Fanshell and ``Ouachita'' 
Fanshell and Designation of Critical Habitat; Final Rule

  Federal Register / Vol. 88 , No. 122 / Tuesday, June 27, 2023 / Rules 
and Regulations  

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R3-ES-2021-0061; FF09E21000 FXES1111090FEDR 234]
RIN 1018-BE79


Endangered and Threatened Wildlife and Plants; Threatened Species 
Status With Section 4(d) Rule for Western Fanshell and ``Ouachita'' 
Fanshell and Designation of Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine 
threatened species status under the Endangered Species Act of 1973 
(Act), as amended, for the western fanshell (Cyprogenia aberti), a 
freshwater mussel species from Arkansas, Kansas, Missouri, and 
Oklahoma, and the ``Ouachita'' fanshell (Cyprogenia cf. aberti), a 
freshwater mussel species from Arkansas and Louisiana. We also 
designate critical habitat for both species. In total, approximately 
261.4 river miles (420.7 kilometers) in Arkansas and Missouri fall 
within the boundaries of the critical habitat designation for western 
fanshell. In total, approximately 227.7 river miles (366.5 kilometers) 
in Arkansas fall within the boundaries of the critical habitat 
designation for ``Ouachita'' fanshell. In addition, we finalize a rule 
under the authority of section 4(d) of the Act that provides measures 
that are necessary and advisable to provide for the conservation of 
these species. This rule extends the Act's protections to these species 
and their designated critical habitats.

DATES: This rule is effective July 27, 2023.

ADDRESSES: This final rule is available on the internet at https://www.regulations.gov, https://www.fws.gov/species/western-fanshell-cyprogenia-aberti, and https://www.fws.gov/species/ouachita-fanshell-cyprogenia-sp-cf-aberti. Comments and materials we received are 
available for public inspection at https://www.regulations.gov under 
Docket No. FWS-R3-ES-2021-0061.
    Supporting materials we used in preparing this rule, such as the 
species status assessment report, are available at https://www.fws.gov/species/western-fanshell-cyprogenia-aberti, https://www.fws.gov/species/ouachita-fanshell-cyprogenia-sp-cf-aberti, and https://www.regulations.gov under Docket No. FWS-R3-ES-2021-0061. For the 
critical habitat designation, the coordinates or plot points or both 
from which the maps are generated are included in the decision file for 
this critical habitat designation and are available at https://www.regulations.gov at Docket No. FWS-R3-ES-2021-0061, and on the 
Service's websites at https://www.fws.gov/species/western-fanshell-cyprogenia-aberti for western fanshell and https://www.fws.gov/species/ouachita-fanshell-cyprogenia-sp-cf-aberti for ``Ouachita'' fanshell.

FOR FURTHER INFORMATION CONTACT: For information about the western 
fanshell, contact John Weber, Field Supervisor, U.S. Fish and Wildlife 
Service, Missouri Ecological Services Field Office, 101 Park DeVille 
Drive, Suite A, Columbia, MO 65203-0057; telephone 573-234-2132. For 
information about the ``Ouachita'' fanshell, contact Melvin Tobin, 
Field Supervisor, U.S. Fish and Wildlife Service, Arkansas Ecological 
Services Field Office, 110 South Amity Road, Suite 300, Conway, AR 
72032-8975; telephone 501-513-4473. 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 endangered 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 
western fanshell and ``Ouachita'' fanshell meet the definition of 
threatened species; therefore, we are listing them as such and 
finalizing a designation of their critical habitat. Both listing a 
species as an endangered or threatened species and designating critical 
habitat can be completed only by issuing a rule through the 
Administrative Procedure Act rulemaking process (5 U.S.C. 551 et seq.).
    What this document does. This rule lists the western fanshell and 
``Ouachita'' fanshell as threatened species and issues regulations 
under section 4(d) of the Act (a ``4(d) rule'') for the conservation of 
both species. This rule designates critical habitat for the western 
fanshell in 6 units totaling approximately 261.4 river miles (river mi) 
(420.7 kilometers (km)) within portions of 6 counties in Arkansas and 4 
counties in Missouri. Additionally, this rule designates critical 
habitat for the ``Ouachita'' fanshell in 3 units totaling approximately 
227.7 river mi (366.5 km) within portions of 12 counties in Arkansas.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species based on 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 western fanshell and 
``Ouachita'' fanshell are threatened due to the following threats: 
water quality degradation, altered flow, landscape changes, and habitat 
fragmentation (Factor A). These threats are reasonably expected to be 
exacerbated by continued urbanization, and threats of water quality 
(temperature) and flow are especially exacerbated by climate change 
(Factor E).
    Section 4(a)(3) of the Act requires the Secretary of the Interior 
(Secretary), to the maximum extent prudent and determinable, to 
designate critical habitat concurrent with listing. Section 3(5)(A) of 
the Act defines critical habitat as (i) the specific areas within the 
geographical area occupied by the species, at the time it is listed, on 
which are found those physical or biological features (I) essential to 
the conservation of the species and (II) which may require special 
management considerations or protections; and (ii) specific areas 
outside the geographical area occupied by the species at the time it is 
listed, upon a determination by the Secretary that such areas are 
essential for the conservation of the species. Section 4(b)(2) of the 
Act states that the Secretary must make the designation on the basis of 
the best scientific data available and after taking into consideration 
the economic impact, the impact on national security, and any other 
relevant impacts of specifying any particular area as critical habitat. 
Also,

[[Page 41725]]

although this critical habitat designation was proposed when the 
regulatory definition of ``habitat'' (85 FR 81411; December 16, 2020) 
and the regulations at 50 CFR 17.90 concerning exclusions from critical 
habitat designation (85 FR 82376; December 18, 2020) were in place and 
in effect, those two regulations have been rescinded (87 FR 37757, June 
24, 2022; 87 FR 43433, July 21, 2022) and no longer apply to any 
designations of critical habitat. Therefore, for this final rule 
designating critical habitat for the western fanshell and ``Ouachita'' 
fanshell, we apply the regulations at 50 CFR 424.19 and the 2016 joint 
(with the National Marine Fisheries Service of the National Oceanic and 
Atmospheric Administration) Policy Regarding Implementation of Section 
4(b)(2) of the Act (81 FR 7226; February 11, 2016).

Previous Federal Actions

    Please refer to our March 3, 2022, proposed rule (87 FR 12338) for 
detailed descriptions of previous Federal actions concerning the 
western fanshell and ``Ouachita'' fanshell.

Peer Review

    A species status assessment (SSA) team prepared an SSA report for 
the western fanshell and ``Ouachita'' fanshell. 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 western 
fanshell and ``Ouachita'' fanshell, including the impacts of past, 
present, and future factors (both negative and beneficial) affecting 
each species.
    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 
2016, memorandum updating and clarifying the role of peer review of 
listing actions under the Act, we solicited independent scientific 
review of the information contained in the SSA report. As discussed in 
our March 3, 2022, proposed rule (87 FR 12338), we sent the SSA report 
to five independent peer reviewers and received two responses. The peer 
reviews can be found at https://www.regulations.gov under Docket No. 
FWS-R3-ES-2021-0061. In preparing the March 3, 2022, proposed rule, we 
incorporated the results of these reviews, as appropriate, into the SSA 
report, which was the foundation for the proposed rule and this final 
rule. A summary of the peer review comments and our responses can be 
found in the Summary of Comments and Recommendations below.

Summary of Changes From the Proposed Rule

    This final rule incorporates changes from our March 3, 2022, 
proposed rule (87 FR 12338) based on the comments that we received and 
respond to in this document, and this rule considers efforts in 
Arkansas and Kansas to conserve the western fanshell and ``Ouachita'' 
fanshell. We made minor, nonsubstantive changes to the SSA report in 
response to comments we received (e.g., we added information on and 
citations for forestry best management practices in the discussion of 
threats in the SSA report). The information we received during the 
comment period did not change our determination that the western 
fanshell and ``Ouachita'' fanshell are threatened species.
    Substantive comments we received during the public comment period 
for the March 3, 2022, proposed rule (see Summary of Comments and 
Recommendations, below) include a request to exclude critical habitat 
from the State of Kansas because of overlap with existing State 
critical habitat designations. Subsequently, the Service approved an 
amendment, submitted by the State of Kansas, to include the western 
fanshell as a covered species under The Kansas Aquatic Species 
Conservation Agreement: A Programmatic Safe Harbor Agreement and 
Candidate Conservation Agreement with Assurances for Fourteen Aquatic 
Species in Kansas (hereafter, the ``Kansas Agreement'') on December 13, 
2022.
    Based on our analysis, which incorporates the value of the Kansas 
Agreement plus two additional agreements in Arkansas, in this final 
rule, we are excluding proposed Unit WF 4 in Arkansas, and all proposed 
critical habitat in Kansas (including proposed Units WF 3 and WF 9, as 
well as a portion of proposed Unit WF 8) for the western fanshell, a 
net decrease of 98.5 river mi (158.4 km) from the proposed designation 
(see table 2, below). We are also excluding proposed Unit OF 2 and a 
portion of proposed Unit OF 4 in Arkansas for ``Ouachita'' fanshell, a 
net decrease of 66.8 river mi (107.4 km) from the proposed designation 
(see table 3, below). More information can be found below under 
Consideration of Impacts under Section 4(b)(2) of the Act, Exclusions 
Based on Other Relevant Impacts.
    To minimize disruptions to surveys and research, we added to the 
4(d) rule a temporary exception for purposeful take that results from 
capture, handling, and release of western fanshell and ``Ouachita'' 
fanshell related to presence/absence surveys, studies to document 
habitat use, and population monitoring by individuals permitted to 
conduct these same activities for other species of mussels for a period 
of 6 months from this final rule's effective date (see DATES, above). 
After the 6-month period, a permit pursuant to section 10(a)(1)(A) of 
the Act is required for the capture and handling of western fanshell 
and ``Ouachita'' fanshell.

Summary of Comments and Recommendations

    In our March 3, 2022, proposed rule (87 FR 12338), we requested 
that all interested parties submit written comments on or before May 2, 
2022. We also contacted appropriate Federal and State agencies, 
scientific experts and organizations, and other interested parties and 
invited them to comment on the proposed rule. Newspaper notices 
inviting general public comment were published in the following 
newspapers: Daily Journal (March 5, 2022), Joplin Globe (March 4, 
2022), Wayne County Journal Banner (March 7, 2022), Daily American 
Republic (March 5, 2022), Arkansas Democratic Gazette (March 6, 2022), 
Examiner-Enterprise (March 8, 2022), Tulsa World (March 6, 2022), 
Independence Daily Reporter (March 5, 2022), The Morning Sun (March 8, 
2022), The Eureka Herald (March 9, 2022), and The Galena Sentinel Times 
(March 9, 2022). We did not receive any requests for a public hearing. 
All substantive information received during the comment period has 
either been incorporated directly into this final rule or is addressed 
below.

Peer Reviewer Comments

    As discussed in Peer Review above, we received comments from two 
peer reviewers on the draft SSA report. We reviewed all comments we 
received from the peer reviewers for substantive issues and new 
information regarding the information contained in the SSA report. The 
peer reviewers generally concurred with our methods and conclusions and 
provided support for thorough and descriptive narratives of assessed 
issues, additional information and citations, clarifications, and 
suggestions to improve the final SSA report. A theme from one reviewer 
indicated that the SSA under-represents available science, specifically 
related to the water quality, flow, and landscape conditions described 
in the SSA. We incorporated available species-specific and river-
specific data into the SSA, including existing high stream

[[Page 41726]]

temperatures and expected rises in the future, the percent of forest 
along an occupied stream, and the density of road crossings. Otherwise, 
no substantive changes to our analyses and conclusions within the SSA 
report were deemed necessary, and peer reviewer comments are addressed 
in version 1.0 of the SSA report.

State Agency Comments

    We received comments from agencies in two States: Kansas and 
Oklahoma.
    (1) Comment: The Kansas Department of Wildlife and Parks (KDWP) 
suggested that overlapping Federal critical habitat with State-
designated critical habitat would not provide additional net benefits 
to the species and requested that we exclude all areas of proposed 
critical habitat in Kansas that are currently designated as State 
critical habitat.
    Our Response: The Service is not relieved of its statutory 
obligation to designate critical habitat based on the contention that 
it will not provide additional conservation benefit (see Ctr. for 
Biological Diversity v. Norton, 240 F. Supp. 2d 1090 (D. Ariz. 2003)). 
However, subsequent to their comment on the proposed rule, the KDWP 
submitted an application to amend the Kansas Agreement to include the 
western fanshell as a covered species. We approved the amendment on 
December 13, 2022. We have determined that the benefits of exclusion 
outweigh the benefits of inclusion of proposed critical habitat in the 
State of Kansas (including proposed Units WF 3 and WF 9, as well as a 
portion of proposed Unit WF 8) for western fanshell, and we are, 
therefore, excluding proposed critical habitat in Kansas from this 
final designation. See Consideration of Impacts under Section 4(b)(2) 
of the Act, below, for more information.
    (2) Comment: The KDWP requested that the 4(d) rule include a 
requirement for consultation with KDWP for channel and bank restoration 
projects, if mussels are found during surveys, to obtain proper State 
permits.
    Our Response: For channel and bank restoration projects, the 4(d) 
rule excepts take incidental to otherwise lawful activities. This means 
that to qualify under this exception, project proponents must satisfy 
all Federal, State, and local permitting requirements. Therefore, we 
have not made any changes to the 4(d) rule in response to this comment.
    (3) Comment: The KDWP recommended that the 4(d) rule include a 
requirement to conduct surveys for species prior to commencing 
transportation project activities and to relocate species in 
consultation with the Service and KDWP.
    Our Response: The exception for incidental take for transportation 
projects in the 4(d) rule covers only those activities that avoid or do 
not include instream disturbance; transportation projects with instream 
disturbance are not covered by this exception. Therefore, requirements 
for surveys are not necessary in this exception, and we have made no 
changes to the 4(d) rule in response to this comment.
    (4) Comment: The KDWP suggested that we add an exception to the 
4(d) rule that all activities associated with conducting scientific 
presence/absence surveys, studies to document habitat use, population 
monitoring, evaluation of potential impacts to the species, and 
relocation efforts be exempt from Service permitting requirements, 
provided that the individual holds a valid scientific collecting permit 
for mussels from the appropriate State wildlife agency.
    Our Response: During the public comment period, we specifically 
sought comments on inclusion of the suggested exception in the 4(d) 
rule. However, we have determined that permitting requirements and 
regulations vary by State and that including this exception in the 4(d) 
rule would not provide for the conservation of the species. Therefore, 
we are not including the suggested exception in this final 4(d) rule.
    To allow time for us to process applications for amendments to 
existing permit holders, the final 4(d) rule does temporarily except 
purposeful take that results from capture, handling, and release of 
western fanshell and ``Ouachita'' fanshell related to presence/absence 
surveys, studies to document habitat use, and population monitoring by 
individuals permitted to conduct these same activities for other 
species of mussels for a period of 6 months from this final rule's 
effective date (see DATES, above).
    (5) Comment: The KDWP suggested that we include an exception in the 
4(d) rule for the temporary collection of females for propagation when 
used in conjunction with approved species recovery efforts by State and 
Federal hatcheries, as well as an exception for holding offspring 
during these efforts, and the Oklahoma Department of Wildlife 
Conservation (ODWC) requested that we include an exception in the 4(d) 
rule for mussel community surveys that are conducted or sponsored by a 
State wildlife agency.
    Our Response: This final 4(d) rule includes an exception for take, 
as set forth at 50 CFR 17.31(b). This provision allows any employee or 
agent of the Service, National Marine Fisheries Service, or State 
conservation agency that is operating a conservation program pursuant 
to the terms of a cooperative agreement with the Service in accordance 
with section 6(c) of the Act, who is designated by that agency for such 
purposes when acting in the course of official duties, to take those 
threatened species of wildlife that are covered by an approved 
cooperative agreement to carry out conservation programs. The temporary 
collection of females for propagation by State hatcheries, holding 
females and offspring for propagation for recovery purposes at State 
hatcheries, and surveys conducted by a State agency or an agent of the 
State are covered under this exception if the activity is included in 
the State's cooperative agreement with the Service. Therefore, an 
additional exception in the 4(d) rule is not necessary, and we made no 
changes to the final rule in response to this comment.
    (6) Comment: The ODWC stated that surveys for western fanshell in 
Oklahoma from 1989 onward have shown the species to be rare and lacking 
a self-sustaining population within the State of Oklahoma. The ODWC 
also indicated that a future mussel community project is planned for 
the Oklahoma portions of the Caney and Verdigris rivers, which will 
provide updated status information for western fanshell in those 
portions.
    Our Response: The most recently documented occurrences of western 
fanshell in Oklahoma from 2006 are likely part of a population 
inhabiting Middle Verdigris River, including both sides of the Kansas-
Oklahoma State line. Available data indicate that population is 
increasing in abundance and is successfully recruiting new juveniles. 
We look forward to updated information from Oklahoma.

Public Comments

    (7) Comment: One commenter stated the scientific literature does 
not justify recognition of ``Ouachita'' fanshell as a distinct species, 
specifically referencing Kim and Roe (2021) findings that more work is 
necessary before the ``genetically distinct clusters'' are formally 
recognized, and the commenter expressed concern with the Service 
listing ``Ouachita'' fanshell as an undescribed species.
    Our Response: We acknowledge that ``Ouachita'' fanshell has not 
been formally recognized by the scientific

[[Page 41727]]

community. However, there is compelling scientific evidence supporting 
its eventual recognition. Kim and Roe (2021, p. 10) found that 
Cyprogenia west of the Mississippi River, within the range of C. 
aberti, form two distinct lineages (Ozark and Ouachita regions) and 
both entities are distinct enough to warrant recognition as separate 
species. We acknowledge that more samples are needed from the Arkansas 
River drainage in Kansas because these samples formed a sister clade to 
the Ozark region C. aberti populations and were also a distinct group 
in the Bayesian clustering analysis (Kim and Roe 2021, p. 10). Because 
Fall and Verdigris rivers in the Arkansas River basin are the type 
localities for the names Unio aberti (Conrad 1850) and Unio popenoi 
(Call 1855), determining the affinities of the Fall and Verdigris River 
populations is essential to the correct name assignment for C. aberti. 
This is the primary reason cited by Kim and Roe (2021, p. 10) for 
waiting on taxonomic changes until additional geographic sampling 
occurs in the Arkansas River basin, specifically pertaining to C. 
aberti from the Ozark region and Arkansas River basin.
    The process for naming a newly recognized species may sometimes 
take longer even though the science has been accepted. We acknowledge 
that questions remain surrounding the application of a specific name to 
``Ouachita'' fanshell, as discussed above; however, this does not 
invalidate the scientific validity of ``Ouachita'' fanshell as a 
separate species. The Act requires us to use the best scientific and 
commercial data available, which indicate that the ``Ouachita'' 
fanshell is a separate species from western fanshell. Therefore, we are 
listing the ``Ouachita'' fanshell as it is currently described. We will 
update this mussel's entry on the List of Endangered and Threatened 
Wildlife once a name has been formally established in the future.
    (8) Comment: One commenter stated that the western fanshell is 
already listed and receives protections under State law in Kansas, 
including State critical habitat; therefore, listing the western 
fanshell as threatened is unnecessary for the conservation of the 
species.
    Our Response: 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 endangered within the foreseeable future 
throughout all or a significant portion of its range). In determining 
whether a species meets the Act's definition of an endangered or 
threatened species, under section 4(b)(1)(A) of the Act, we are 
required to make that determination based solely on the best scientific 
and commercial data available. Based on the best available scientific 
and commercial data, we have determined that western fanshell and 
``Ouachita'' fanshell are threatened species due to the following 
threats: water quality degradation, altered flow, landscape changes, 
and habitat fragmentation (Factor A). These threats are reasonably 
expected to be exacerbated by continued urbanization, and threats of 
water quality (temperature) and flow are especially exacerbated by 
climate change (Factor E). Based on our analysis, we have determined 
that the western fanshell and ``Ouachita'' fanshell meet the Act's 
definition of threatened species; therefore, we are listing them as 
such and finalizing a designation of their critical habitat. Under 16 
U.S.C. 1531(b), the purposes of listing and designation of critical 
habitat under the Act for these mussel species and other listed species 
are to provide, in part, a means whereby the ecosystems upon which they 
depend may be conserved and to provide a program for the species' 
conservation.
    (9) Comment: One commenter suggested expanding the 4(d) rule to 
expressly include all conservation efforts beneficial to the species, 
such as scientific studies and monitoring, as well as an exception from 
take for conservation efforts (including propagation and holding of 
offspring until they can be stocked). The commenter suggested that 
without this expansion, conservation efforts would be complicated and 
neighboring landowners would be less willing to participate in 
conservation programs or to allow conservation efforts on their lands 
because of the risk of liability under the Act.
    Our Response: Existing agreements between the Service and State 
wildlife agencies under section 6 of the Act already provide 
authorization for the States to perform surveys and conduct other 
conservation work on listed species. As noted above (see our response 
to (4) Comment), we have concluded that an exception to requirements 
for obtaining a permit for surveys under section 10(a)(1)(A) of the Act 
would not provide for the conservation of the species due to varying 
permitting requirements and regulations among States. Programs are 
available to private landowners for managing habitat for listed 
species; permits can also be obtained to protect private landowners 
from the take prohibition when such taking is incidental to, and not 
the purpose of, the carrying out of an otherwise lawful activity. 
Private landowners may contact their local Service field office to 
obtain information about these programs and permits.
    However, this final 4(d) rule does temporarily except purposeful 
take that results from capture, handling, and release of western 
fanshell and ``Ouachita'' fanshell related to presence/absence surveys, 
studies to document habitat use, and population monitoring by 
individuals permitted to conduct these same activities for other 
species of mussels for a period of 6 months from this final rule's 
effective date (see DATES, above).
    (10) Comment: One commenter expressed concern that listing could 
frustrate the KDWP and private landowners and complicate conservation 
measures taken by them for the conservation of the western fanshell and 
other aquatic species.
    Our Response: We understand that listing the western fanshell may 
generate concern about the effect on conservation efforts. The KDWP 
applied for an amendment to include the western fanshell as a covered 
species under the Kansas Agreement, which we approved on December 13, 
2022. Inclusion of the species in the Kansas Agreement will enhance 
engagement with private landowners to implement conservation actions 
for the species by providing assurances to landowners and removing 
regulatory uncertainty.
    (11) Comment: One commenter stated that the areas proposed as 
critical habitat for western fanshell in Kansas overlap with critical 
habitat for State-listed species and, therefore, are redundant and 
unnecessary.
    Our Response: The Service is not relieved of its statutory 
obligation to designate critical habitat based on the contention that 
it will not provide additional conservation benefit. In Ctr. for 
Biological Diversity v. Norton, 240 F. Supp. 2d 1090 (D. Ariz. 2003), 
the court held that the Act does not direct us to designate critical 
habitat only in those areas where ``additional'' special management 
considerations or protection are needed. See also Cape Hatteras Access 
Preservation Alliance v. U.S. Dept. of Interior, 731 F.Supp.2d (D.D.C. 
2010). If any area provides the PBFs essential to the conservation of 
the species, even if that area is already well managed or protected, 
that area may still qualify as critical habitat under the statutory 
definition.
    (12) Comment: One commenter stated that the proposed rule's 
description of water quality threats is generic and fails

[[Page 41728]]

to point out which specific contaminants have led to mussel population 
declines in the proposed critical habitat units.
    Our Response: The water quality parameters we considered are 
discussed in the Species Needs, ``Water Quality,'' and Physical or 
Biological Features Essential to the Conservation of the Species 
discussions in the proposed rule (see 87 FR 12338, March 3, 2022, pp. 
12344, 12354) and in the same discussions (below) in this final rule. 
Specific contaminants and their toxicity levels are discussed in the 
SSA report (Service 2022, pp. 53-58). These contaminants include total 
ammonia nitrogen (TAN), nitrates and nitrites, cadmium, copper, zinc, 
and lead. Table 4.4 of the SSA report lists the toxicity levels of each 
contaminant, and table 4.6 shows the data by river (Service 2022, pp. 
35, 41). Water quality data indicate the two fanshell mussels have been 
exposed to nitrates, nitrites, zinc, and copper at concentrations that 
cause acute toxicity and may be exposed to toxic levels of lead in the 
future (Service 2022, p. 55). However, our results indicated that TAN 
and cadmium were not stressors to either species now or in future 
scenarios (Service 2022, p. 36). Water quality data are available for 
each river within the species' ranges but not for each critical habitat 
unit specifically.
    (13) Comment: One commenter noted that ammonia nitrogen levels and 
low dissolved oxygen were not found to be threats and suggested the 
4(d) rule should include an exception for take resulting from standard 
agricultural practices to allow neighboring landowners to continue 
their routine agricultural practices and incentivize partnerships 
between the landowner, State, and Service.
    Our Response: Under section 4(d) of the Act, when we list a species 
as a threatened species, we issue such regulations as deemed necessary 
and advisable to provide for the conservation of the species. In 
species-specific 4(d) rules, we focus our efforts on incentivizing 
known beneficial actions for the species, as well as removing the 
regulatory burden on forms of take that are considered inconsequential 
to the conservation of the species. While the SSA report did not find 
TAN or low dissolved oxygen were threats to either species (Service 
2022, p. 36), our analysis found nitrates, nitrites, and sedimentation 
with agricultural activities as partial sources are threats to both 
species (Service 2022, pp. 40, 55-57). While we carefully considered 
this request, excepting incidental take from agricultural activities 
would not provide a clear conservation benefit to the western fanshell 
or ``Ouachita'' fanshell, and we did not include this exception in the 
final 4(d) rule.
    We acknowledge that building partnerships and promoting cooperation 
of landowners are essential to understanding the status of species on 
non-Federal lands and may be necessary to implement recovery actions 
such as habitat restoration. For private landowners, we offer voluntary 
SHAs that can contribute to the recovery of species, habitat 
conservation plans (HCPs) that allow activities to proceed while 
minimizing effects to species, and funding through the Partners for 
Fish and Wildlife Program to help promote conservation actions.
    (14) Comment: One commenter expressed concern that not many channel 
and bank restoration and transportation projects would qualify as 
projects that do not involve disturbing the water as stipulated in the 
proposed 4(d) rule.
    Our Response: The purpose of the 4(d) rule is to incentivize 
positive conservation actions and streamline the regulatory process for 
minor impacts. To clarify, the exception in the 4(d) rule for channel 
and bank restoration does not require that projects do not disturb 
instream waters. The exception for transportation projects is for those 
projects that avoid instream disturbance in waters occupied by the 
western fanshell or ``Ouachita'' fanshell. We are not excepting take 
from transportation projects with instream disturbance because these 
project types may require incorporation of site-specific measures to 
avoid and minimize effects to the western fanshell or ``Ouachita'' 
fanshell.
    (15) Comment: One commenter expressed concern that critical habitat 
may lead to severe restrictions to private property and restricting 
bank stabilization and channel maintenance activities in the critical 
habitat units will limit stream restoration activities benefiting the 
species.
    Our Response: The designation of critical habitat will not impose 
any restrictions on non-Federal actions for private landowners, 
provided there is no Federal nexus. If there is a Federal nexus and the 
action of the Federal agency may affect the species or its designated 
critical habitat, then the Federal agency will need to consult with the 
Service. However, the 4(d) rule provides, among others, an exception 
for take related to channel and bank restoration projects. Although the 
4(d) rule does not alleviate a Federal agency's obligation to consult 
under section 7 of the Act, this exception for channel and bank 
restoration projects will help to streamline future consultations.

I. Final Listing Determination

Background

    The western fanshell (Cyprogenia aberti) is a freshwater mussel in 
the Unionidae family. Adults are a dull tan with a distinctive ray 
pattern from bands of tiny pigment flecks. The shell is thick, 
compressed to moderately inflated, and round to triangular (up to 3 
inches (76 millimeters)), with a wrinkled or rough appearance (Conrad 
1850, p. 10; McMurray et al. 2012, p. 30; Oesch 1995, pp. 143-144; Roe 
2004, pp. 4-5).
    Recent molecular analysis of Cyprogenia identified the fanshell 
from the Ouachita River basin in Arkansas and Louisiana as an 
independent evolutionary lineage (Kim and Roe 2021, p. 10; Chong et al. 
2016, pp. 2445-2449). There is uncertainty regarding what name is 
available for the Ouachita River drainage fanshell. Further taxonomic 
changes are pending additional geographic sampling to understand the 
correct name assignment (Kim and Roe 2021, p. 10), but this does not 
invalidate the distinctiveness of the Ouachita River basin Cyprogenia 
as a separate species.
    The Arkansas Wildlife Action Plan refers to the species as the 
``Ouachita'' fanshell (C. cf. aberti) (Arkansas Game and Fish 
Commission 2015, p. 974). Based on this information, we find the 
``Ouachita'' fanshell is a listable entity under the Act, and we follow 
this naming convention until a specific epithet can be designated.
    The western fanshell is currently found in the Lower Mississippi-
St. Francis, Neosho-Verdigris, and Upper White River basins, within the 
States of Arkansas, Kansas, Missouri, and Oklahoma (Service 2022, pp. 
22-29; see figure 1, below). It is considered extirpated from the Lower 
Arkansas basin. The ``Ouachita'' fanshell currently occurs in the Lower 
Red-Ouachita basin in Arkansas and historically in Louisiana (Service 
2022, pp. 29-32; see figure 2, below).
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    Both species are typically found in large creeks and rivers with 
good water quality, moderate to swift current, and gravel-sand 
substrates, but specific information on microhabitat requirements is 
lacking. Like all mussels, these two species of fanshell are omnivores 
that primarily filter-feed on a wide variety of microscopic particulate 
matter suspended in the water column, including phytoplankton, 
zooplankton, bacteria, detritus, and dissolved organic matter (Haag 
2012, p. 26). As with most freshwater mussels,

[[Page 41731]]

the fanshell mussels have a unique life cycle that relies on fish hosts 
for successful reproduction (Barnhart et al. 2008, pp. 371-373; Vaughn 
and Taylor 1999, p. 913; Barnhart 1997, p. 12).
    Thorough reviews of the taxonomy, life history, and ecology of the 
western fanshell and ``Ouachita'' fanshell are presented in detail in 
the SSA report (Service 2022, pp. 9-16).

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 threats on the 
species as a whole. We also consider the cumulative effect of the 
threats in light of those actions and conditions that will have 
positive effects on the species, such as any existing regulatory 
mechanisms or conservation efforts. The Secretary determines whether 
the species meets the definition of an ``endangered species'' or a 
``threatened species'' only after conducting this cumulative analysis 
and describing the expected effect on the species now and in the 
foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as the 
Services can reasonably determine that both the future threats and the 
species' responses to those threats are likely. In other words, the 
foreseeable future is the period of time in which we can make reliable 
predictions. ``Reliable'' does not mean ``certain''; it means 
sufficient to provide a reasonable degree of confidence in the 
prediction. Thus, a prediction is reliable if it is reasonable to 
depend on it when making decisions.
    It is not always possible or necessary to define the foreseeable 
future as a particular number of years. Analysis of the foreseeable 
future uses the best scientific and commercial data available and 
should consider the timeframes applicable to the relevant threats and 
to the species' likely responses to those threats in view of its life-
history characteristics. Data that are typically relevant to assessing 
the species' biological response include species-specific factors such 
as lifespan, reproductive rates or productivity, certain behaviors, and 
other demographic factors.
Analytical Framework
    The SSA report documents the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of both species, including an assessment of potential 
threats to the species. The SSA report does not represent our decision 
on whether either species should be listed as an endangered or 
threatened species under the Act. However, it does provide the 
scientific basis that informs our regulatory decisions, which involve 
the further application of standards within the Act and its 
implementing regulations and policies.
    To assess the western fanshell's and ``Ouachita'' fanshell's 
viability, we used the three conservation biology principles of 
resiliency, redundancy, and representation (Shaffer and Stein 2000, pp. 
306-310). Briefly, resiliency is the ability of the species to 
withstand environmental and demographic stochasticity (for example, wet 
or dry, warm or cold years), redundancy is the ability of the species 
to withstand catastrophic events (for example, droughts, large 
pollution events), and representation is the ability of the species to 
adapt to both near-term and long-term changes in its physical and 
biological environment (for example, climate conditions, pathogens). In 
general, species viability will increase with increases in resiliency, 
redundancy, and representation (Smith et al. 2018, p. 306). Using these 
principles, we identified the species' ecological requirements for 
survival and reproduction at the individual, population, and species 
levels and described the beneficial and risk factors influencing the 
species' viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the individual species' life-
history needs. The next stage involved an assessment of the historical 
and current condition of the

[[Page 41732]]

species' demographics and habitat characteristics, including an 
explanation of how the species arrived at its current condition. The 
final stage of the SSA involved making predictions about the species' 
responses to positive and negative environmental and anthropogenic 
influences. Throughout all of these stages, we used the best available 
information to characterize viability as the ability of a species to 
sustain populations in the wild over time. We use this information to 
inform our regulatory decision.
    The following is a summary of the key results and conclusions from 
the SSA report for the western fanshell and ``Ouachita'' fanshell; the 
full SSA report can be found in Docket No. FWS-R3-ES-2021-0061 at 
https://www.regulations.gov.

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
western fanshell and ``Ouachita'' fanshell, their resources, and the 
threats that influence both species' current and future condition, to 
assess each species' overall viability and the risks to that viability.
Species Needs
    Fanshell mussels feed primarily on a wide variety of microscopic 
particulate matter, including phytoplankton, zooplankton, bacteria, 
detritus, and dissolved organic matter (Haag 2012, p. 26). Juveniles 
likely pedal feed in the sediment, whereas adults filter-feed from the 
water column.
    As with most freshwater mussels, both fanshell mussels rely on a 
host fish for reproduction. The female mussel holds the fertilized eggs 
internally as they develop into larvae. Once mature, the larvae are 
released as glochidia, which attach on the gills, head, or fins of 
fishes (Barnhart et al. 2008, pp. 371-373; Vaughn and Taylor 1999, p. 
913). Glochidia encyst (enclose in a cyst-like structure) on the host's 
tissue and draw nutrients from the fish. The glochidia for the fanshell 
mussels remain encysted for about a month until transformation to the 
juvenile stage, at which point they release from the fish and drop to 
the substrate (Barnhart 1997, p. 12). Glochidia die if they fail to 
find a host fish, attach to the wrong species of host fish, attach to a 
fish that has developed immunity from prior infestations, or attach to 
the wrong location on a host fish (Bogan 1993, p. 599; Neves 1991, p. 
254).
    Logperch (Percina caprodes) is a suitable fish host for both 
fanshell species in all river basins (Eckert 2003, pp. 18-19). 
Slenderhead darter (Percina phoxocephala) and orangebelly darter 
(Etheostoma radiosum) are suitable hosts for ``Ouachita'' fanshell 
(Eckert 2003, p. 46), while slenderhead darter, fantail darter 
(Etheostoma flabellare), rainbow darter (Etheostoma caeruleum), and 
orangebelly darter are suitable hosts for western fanshell, but only 
for their respective sympatric fanshell mussel population (Eckert 2003, 
p. 33). In other words, glochidia had greater success transforming on 
darters from the same stream as the mussel. For example, a higher 
percentage of glochidia from Ouachita River transformed on orangebelly 
darters from Ouachita River than on orangebelly darters from Verdigris 
River (Eckert 2003, p. 11).
    We assessed the best available information to identify the physical 
and biological needs to support individual fitness at all life stages 
for the western fanshell and ``Ouachita'' fanshell. Full descriptions 
of all needs are available in chapter 2 of the SSA report (Service 
2022, pp. 9-16). Based upon the best available scientific and 
commercial information, the resource needs for both species are 
characterized as:
     Stable river channels and banks (for example, stable 
riffles, sometimes with runs, and mid-channel island habitats that 
provide flow refuges), consisting of mixed sand, gravel, and cobble 
substrates with low to moderate amounts of fine sediment and attached 
filamentous algae;
     A hydrologic flow regime (the severity, frequency, 
duration, and seasonality of discharge over time) that maintains the 
benthic habitats where the species are found and the river connectivity 
with the floodplain;
     Habitat connectivity (that is, a lack of barriers for 
passage of host fish, which are necessary for dispersal of mussels);
     Water and sediment quality, such as (but not limited to) 
dissolved oxygen above 3 parts per million (ppm), ammonia generally 
below 1.0 ppm total ammonia-nitrogen, temperatures generally below 80 
degrees Fahrenheit ([deg]F) (27 degrees Celsius ([deg]C)), low 
concentrations of metals, and an absence of excessive total suspended 
solids and other pollutants;
     The presence and abundance of fish hosts (logperch, 
slenderhead darter, fantail darter, rainbow darter, and orangebelly 
darter) necessary for recruitment of the fanshell mussels; and
     Appropriate food sources (phytoplankton, zooplankton, 
protozoans, detritus, and dissolved organic matter) in adequate supply.
Threats Analysis
    We identified water quality degradation, altered flow, landscape 
changes, and habitat fragmentation, all of which are exacerbated by the 
effects of climate change, as the primary threats affecting the western 
fanshell and ``Ouachita'' fanshell (Service 2022, p. 53). We 
acknowledge that invasive species can have individual and, in some 
circumstances, population-level effects to mussels. However, the best 
available data do not support that invasive species are a driving force 
affecting the current or future conditions of these two fanshell 
mussels (Service 2022, pp. 64-65). The primary threats are discussed 
below.
    Given that both of the fanshells' ranges include medium to large 
rivers with some populations fragmented by dams and creation of 
navigation channels, we delineated separate populations for each 
watershed through which these streams flow (if there was an occurrence 
record for the stream in that watershed), based on the hydrologic unit 
code (HUC) (Seaber et al. 1987, entire; U.S. Geological Survey 2018, 
entire) at the fourth of six levels (that is, the HUC-8 watershed), and 
termed these ``management units'' (MUs). MUs represent areas with one 
or more populations capable of dispersal and interaction. As a result, 
some watersheds have been combined into one management unit because of 
a lack of dispersal barriers and some divided into multiple management 
units. MUs were identified as most appropriate for assessing 
population-level resiliency because the stream level was determined to 
be too coarse of a scale to estimate the condition factors influencing 
resiliency (Service 2022, p. 17). We defined a MU as currently extant 
if it contains live or recent dead individuals observed in surveys from 
2000 to the present (Service 2022, p. 22).
Water Quality
    Chemical contaminants are a major threat in the decline of mussel 
species (Cope et al. 2008, p. 451; Richter et al. 1997, p. 1081; 
Strayer et al. 2004, p. 436; Wang et al. 2007a, p. 2029). Chemicals 
enter rivers through point and nonpoint discharges, including spills, 
industrial and municipal effluents, and residential and agricultural 
runoff. These sources contribute organic compounds, heavy metals, 
nutrients, pesticides, and a wide variety of newly emerging 
contaminants, such as pharmaceuticals, to the aquatic environment.
    The western fanshell has been exposed to zinc and copper at

[[Page 41733]]

concentrations that cause acute toxicity (Service 2022, p. 41) and may 
be exposed to toxic levels of lead in the future (Service 2022, 
appendix I-D-I-E). Metals from mine water runoff (for example, the Tri-
State Mining District in southwest Missouri and southeast Kansas) 
contributed to mussel declines in Shoal Creek and Spring River in the 
Arkansas River basin (Angelo et al. 2007, p. 467; EcoAnalysts, Inc. 
2018, p. 59).
    Nutrients, such as nitrogen and phosphorus, primarily occur in 
runoff from livestock farms, feedlots, heavily fertilized row crops and 
pastures (Peterjohn and Correll 1984, p. 1471), post timber management 
activities, and urban and suburban runoff (including residential lawns 
and leaking septic tanks). Sources of ammonia include agricultural 
wastes (animal feedlots and nitrogenous fertilizers), municipal 
wastewater treatment plants, and industrial waste (Augspurger et al. 
2007, p. 2569), as well as precipitation and natural processes 
(decomposition of organic nitrogen) (Augspurger et al. 2003, p. 2569; 
Goudreau et al. 1993, p. 212; Hickey and Martin 1999, p. 44; Newton et 
al. 2003, p. 1243). As discussed above under Species Needs, both 
fanshell species require dissolved oxygen above 3 ppm and ammonia 
generally below 1.0 ppm total ammonia-nitrogen. We analyzed total 
ammonia nitrogen data in rivers occupied by the two fanshell mussel 
species but did not find concentrations at levels expected to result in 
acute or chronic toxicity to mussels (Service 2022, p. 41, appendix I-
D-I-E). In addition, nutrient enrichment increases primary 
productivity, and the associated algae respiration depletes dissolved 
oxygen levels. However, available water quality data indicate that 
hypoxia (low dissolved oxygen) is not occurring in occupied streams and 
is not currently a threat to the fanshell mussels.
Flow
    Reductions in the diversity and abundance of mussels are 
principally attributed to habitat alteration caused by inundation of 
free-flowing rivers and streams (Neves et al. 1997, p. 60), which has 
occurred in portions of the fanshell mussels' ranges (for example, 
White, Ouachita, Caddo, and Neosho rivers). The construction of 
reservoirs and other impoundments permanently alters the hydrology, 
with deleterious effects to fish host movement and mussel dispersal.
    The water released from the hypolimnion (lower layers of the lake) 
in large reservoirs is cold and often devoid of oxygen and necessary 
nutrients, which adversely affects mussel survival. Cold water can 
stunt mussel growth and delay or hinder spawning (Vaughn and Taylor 
1999, p. 917). Reservoirs, like Bull Shoals on the White River in 
north-central Arkansas, that release cold water from the bottom of the 
reservoir (in part to support nonnative rainbow trout and brown trout 
recreational fisheries) can affect water temperatures for many 
kilometers downstream. These cold releases create an extinction 
gradient, where freshwater mussels are absent or present in low numbers 
near the dam, and abundance does not rebound until some distance 
downstream where ambient conditions raise the water temperature to 
within the tolerance limits of mussels (Vaughn and Taylor 1999, pp. 
915-916).
    In addition to low water temperature limits, freshwater mussels 
also have an upper water temperature threshold. As described above 
under Species Needs, both fanshell species require water temperatures 
generally below 80 [deg]F (27 [deg]C).
    In ``Ouachita'' fanshell occupied streams from 1990 to 2018, the 
percent of water temperature samples exceeding 27 [deg]C ranged from 
6.9 to 15.4 percent, with maximum water temperature ranging from 30.3 
[deg]C to 36.6 [deg]C. In western fanshell MUs from 1990 to 2018, the 
percent of water temperature samples exceeding 27 [deg]C ranged from 0 
to 12.6 percent, with maximum water temperature ranging from 22.0 
[deg]C to 35.8 [deg]C.
    Recruitment in some species of mussels is significantly related to 
components of spring and summer flow (Ries et al. 2016, p. 711). High 
velocity flows during spawning can decrease fertilization success (Ries 
et al. 2016, p. 712) and affect juvenile settling (Daraio et al. 2010, 
p. 838; Hardison and Layzer 2001, p. 77). Mussel beds may be 
constrained by threshold limits at both flow extremes. Under low flow 
conditions, mussels may require a minimum flow to transport nutrients, 
oxygen, and waste products. Under high flow conditions, areas with 
relatively low flow may provide a refuge for mussels (Steuer et al. 
2008, p. 67). Fanshell mussels undoubtedly evolved in the presence of 
extreme hydrological conditions to some degree, including severe 
droughts leading to dewatering, and heavy rains leading to damaging 
scour events and movement of mussels and substrate, although the 
frequency, duration, and intensity of these events may be different 
from today. Streamflow and overall discharge for rivers inhabited by 
western and ``Ouachita'' fanshell mussels will likely decline due to 
climate change and projected increases in temperatures and evaporation 
rates, resulting in more frequent and intense droughts (LaFontaine et 
al. 2019, entire).
    Excessive sediments adversely affect riverine mussel populations 
requiring clean, stable streams (Brim Box and Mossa 1999, p. 99; Ellis 
1936, pp. 39-40). Specific biological effects include reduced feeding 
and respiratory efficiency from clogged gills, disrupted metabolic 
processes, reduced growth rates, limited burrowing activity, physical 
smothering, and disrupted host fish attraction mechanisms (Ellis 1936, 
pp. 39-40; Hartfield and Hartfield 1996, p. 373; Marking and Bills 
1979, p. 210; Vannote and Minshall 1982, pp. 4105-4106; Waters 1995, 
pp. 173-175). The physical effects of sediment on mussel habitat 
include changes in suspended and bed material load; changes in bed 
sediment composition associated with increased sediment production and 
runoff in the watershed; channel changes in form, position, and degree 
of stability; changes in depth or the width and depth ratio that 
affects light penetration and flow regime, actively aggrading (filling) 
or degrading (scouring) channels; and changes in channel position. 
These effects to habitat may dislodge, transport downstream, or leave 
mussels stranded (Brim Box and Mossa 1999, pp. 109-112; Kanehl and 
Lyons 1992, pp. 4-5; Vannote and Minshall 1982, p. 4106).
    Most sediment transport occurs during floods (Clark and Mangham 
2019, pp. 6-7; Kondolf 1997, p. 533). An increase in flooding severity 
results in greater sediment transport, with important effects to 
substrate stability and benthic habitats for freshwater mussels, as 
well as other organisms that are dependent on stable benthic habitats 
(Kondolf 1997, p. 535). High base flows can incise channels, erode 
riverbanks, scour mussel beds, and remove substrate preferred by 
mussels. Over time, the physical force of these higher base flows can 
dislodge mussels from the sediment and permanently alter the 
geomorphology of rivers (Clark and Mangham 2019, pp. 6-7; Kondolf 1997, 
p. 533).
    Runoff from impervious surfaces prevalent in urban areas affects 
the natural hydrology of streams by increasing flood magnitude, 
duration, and frequency (Bressler et al. 2009, p. 292). Frequent floods 
in urban areas scour stream substrate and banks, thereby increasing 
erosion and sedimentation and altering geomorphology. Geomorphic 
changes, such as changes in channel width, occur with impervious areas 
as low as 2 to 10 percent (Booth and Jackson 1997, p.

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1084; Dunne and Leopold 1978, pp. 275-277; Morisawa and LaFlure 1979, 
figure 11). Initial degradation of fish communities and lower larval 
densities have been associated with as low as 10 percent impervious 
areas (Limburg and Schmidt 1990, pp. 1241-1242; Steedman 1988, pp. 498-
499). Unpaved road networks also interact with streams, delivering 
sediment runoff and increasing water velocity entering stream channels, 
thereby increasing stream energy, eroding streambanks, scouring 
channels, and increasing flooding (Coffin 2007, pp. 397-398).
Landscape Alterations
    Many rivers where the western fanshell and ``Ouachita'' fanshell 
occur are threatened by land use activities and changes (for example, 
increased urbanization, alteration of riparian buffers, improperly 
designed and maintained unpaved roads). Urbanization of a watershed can 
result in increased pollutant loads from stormwater runoff, altered 
flow, decreased bank stability, and increased water temperature. 
Urbanization can also indirectly increase channel erosion and 
downstream sedimentation by increasing the frequency and volume of 
channel-altering storm flows (Hammer 1972, p. 1530; Leopold 1968, 
entire). These effects of urbanization can lower fish species richness 
and density, leading to predictable changes in species composition, and 
these changes can accrue rapidly (less than 10 years) and are 
detectable at low levels (approximately 5 to 10 percent urbanization) 
(Walters et al. 2005, p. 1). In 2016, 80 percent of the western and 
``Ouachita'' fanshell MUs had 5 percent or greater urban land use, but 
all were less than 10 percent (Service 2022, appendix I-A).
    The amount of impervious surface and riparian forest cover 
influences stream hydrology and water quality (Brabec et al. 2002, pp. 
505-507). Riparian forest cover intercepts and moderates the timing of 
runoff, buffers temperature extremes, filters pollutants in runoff, 
provides woody debris to stream channels that enhances aquatic food 
webs, and stabilizes excessive erosion. Furthermore, the removal of 
riparian trees in forested watersheds has a strong influence on stream 
invertebrate communities (Wallace et al. 1997, entire). In 2016, forest 
cover ranged from 70 to 76 percent in ``Ouachita'' fanshell MUs and 
from 12 to 77 percent in western fanshell MUs (Service 2022, appendix 
I-A).
    Agricultural practices, such as livestock grazing and tilling on 
land adjacent to streams, can lead to soil erosion and subsequent 
runoff of fine sediments, nutrients, and pesticides (for example, 
Schulz and Liess 1999, p. 155). Watersheds with the most habitat 
converted to farmland often have the greatest levels of mussel richness 
decline (Poole and Downing 2004, p. 123). In 2016, agricultural land 
use ranged from 5 to 13 percent in ``Ouachita'' fanshell MUs and from 
17 to 68 percent in western fanshell MUs and decreased in all MUs for 
both species from 2011 to 2016 (Service 2022, appendix I-A).
    Roads adversely affect watershed integrity by intercepting, 
concentrating, and diverting water. Roads directly affect natural 
sediment and hydrologic regimes by altering stream flow, sediment 
loading, sediment transport and deposition, channel morphology, channel 
stability, substrate composition, stream temperature, water quality, 
and riparian condition (Lee et al. 1997, pp. 1102-1104). Hydrologic 
effects are sensitive to road density, with increased peak flows 
evident at road densities of 2 to 3 kilometers (km)/square kilometers 
(km\2\) (Forman and Alexander 1998, p. 223). In 2016, unpaved road 
density in all the western and ``Ouachita'' fanshell mussel MUs were 
1.6 km/km\2\ or less.
Habitat Fragmentation
    Hydrologic and geomorphic processes directly relate to habitat 
extent. The number and distribution of habitat patches and their 
connectivity influence species population health. Historically, the two 
fanshell species likely occurred throughout the river basins described 
in the SSA report (Service 2022, pp. 22-32). Large-scale reductions in 
mussel diversity and abundance are largely due to habitat changes 
caused by impoundments (Neves et al. 1997, p. 63). The number of 
impoundments in ``Ouachita'' fanshell MUs ranges from 3 to 51, and in 
western fanshell MUs ranges from 4 to 73.
Effects of Climate Change
    We examined information on the anticipated effects of climate 
change, including changes to water temperatures and precipitation 
patterns. In its 5th Assessment Report, the Intergovernmental Panel on 
Climate Change (IPCC) adopted ``representative concentration pathways'' 
(RCPs), which are greenhouse gas concentration trajectories, to 
describe potential future climate outcomes, depending on the amount of 
greenhouse gases that are emitted in the future (IPCC 2014, pp. 126-
127). Under RCP4.5 and RCP8.5, the seasonal averages of 30 Coupled 
Model Intercomparison Project 5 (CMIP5) models from 1950 to 2100 
indicate warming air temperatures in the Lower Mississippi River 
region, with a central tendency of less than 2 inches change in 
precipitation (Alder and Hostetler 2013, pp. 2-3). We expect changes in 
stream temperatures to reflect changes in air temperature, at a rate of 
an approximately 0.6-0.8 [deg]C increase in stream water temperature 
for every 1 [deg]C increase in air temperature (Morrill et al. 2005, 
pp. 1-2, 15). These water temperature changes will have implications 
for temperature-dependent water quality parameters (such as dissolved 
oxygen and ammonia toxicity), spawning, and physiological effects to 
thermally sensitive species.
    Future increases in the frequency and severity of both extreme 
drought and extreme rainfall are expected to transform many ecosystems 
in the Southeast, including Arkansas (Carter et al. 2018, pp. 743-808). 
Mussels are highly sensitive to secondary effects of drought (for 
example, water temperature, etc.), but their ability to withstand 
severe drought is highly dependent on where they occur (Haag and Warren 
2008, p. 1165) and sufficient time between sequential drought events 
for mussel populations to recover (Vaughn et al. 2015, pp. 1297-1298).
    We also considered whether the threats discussed above may be 
exacerbated by small population size (or low condition). Although there 
are populations in low condition in all the basins in which the two 
species occur, none of the basins have seen their populations reduced 
to one or two populations in low condition.
Regulatory Mechanisms
State Protections
    In Kansas, the western fanshell is listed as State endangered with 
designated critical habitats under the Kansas Nongame and Endangered 
Species Conservation Act. Under State law, any time an eligible project 
is proposed that will impact the species' preferred habitats within its 
probable range in Kansas, the project sponsor must contact the KDWP 
regarding potential permit requirements. In addition, Kansas manages 
the take and possession of mussels for personal use and prohibits the 
personal take of any mussel species listed as endangered or threatened 
by Kansas or the Federal Government. The western fanshell and 
``Ouachita'' fanshell do not receive protection under State law in any 
other States.

[[Page 41735]]

Other Regulatory Mechanisms
    The U.S. Forest Service (2005, p. 58) established a wildlife and 
fish habitat road density objective of less than or equal to 1.6 km/2.6 
km\2\ on the Ouachita National Forest in west-central Arkansas, which 
includes the Ouachita Headwaters and Caddo MUs for ``Ouachita'' 
fanshell. The Arkansas Unpaved Roads Program, authorized by that 
State's Act 898 of the 90th General Assembly in 2015, establishes a 
proactive, incentive-based management program that results in 
utilization of best management practices on unpaved roads to minimize 
erosion and maintain and improve the health of priority lakes and 
rivers (TNC 2017, entire), including those where both fanshell mussel 
species occur.
Current Conditions
    We described current (and future) conditions using categories that 
estimate the overall condition (resiliency) of the western fanshell and 
``Ouachita'' fanshell populations. These categories are based on an 
evaluation of multiple population and habitat factors (Service 2022, 
pp. 17-21). In the absence of species-specific genetic information, we 
used contiguous hydrologic units at the HUC-4 level to assess the 
species' genetic, ecological, and geographical diversity 
(representation), and we used the number of populations and MUs to 
describe the species' redundancy.
Western Fanshell
    The western fanshell's current range includes a total of 11 MUs 
across three HUC-4 units: Neosho-Verdigris (2 MUs), Lower Mississippi-
St. Francis (3 MUs), and Upper White (6 MUs) river drainages of 
Arkansas, Missouri, Kansas, and Oklahoma. Historically, the western 
fanshell occurred in another 14 MUs and is presumed extirpated from the 
Lower Arkansas (HUC-4) river drainage. Of the current MUs, three (27 
percent) are estimated to be highly resilient, three (27 percent) are 
estimated to be moderately resilient, and five (46 percent) are 
estimated to have low resiliency (Service 2022, pp. 37-46). The habitat 
conditions across the 11 extant populations are medium to high (Service 
2022, p. 42).
``Ouachita'' Fanshell
    The ``Ouachita'' fanshell currently occurs in four MUs within 
portions of the Ouachita River basin (HUC-4) in Arkansas. One MU is 
presumed extirpated. Of the current MUs, one (25 percent) is estimated 
to be highly resilient, one (25 percent) is estimated to be moderately 
resilient, and two (50 percent) are estimated to have low resiliency 
(Service 2022, pp. 47-49). The habitat conditions across the four 
extant populations are medium to high (Service 2022, p. 50).

Future Conditions

    We forecasted the western fanshell's and ``Ouachita'' fanshell's 
responses to plausible future scenarios of varying environmental 
conditions. The future scenarios project the threats into the future 
and consider the impacts those threats could have on the viability of 
the western fanshell and ``Ouachita'' fanshell. We apply the concepts 
of resiliency, redundancy, and representation to the future scenarios 
to describe possible future conditions of the western fanshell and 
``Ouachita'' fanshell. The scenarios described in the SSA report 
represent the plausible upper and lower bounds of the future conditions 
for each species. Uncertainty is inherent in any projection of future 
condition, so we must consider plausible scenarios to make our 
determinations. When assessing the future, viability is not a specific 
state, but rather a continuous measure of the likelihood that the 
species will sustain populations over time.
    In the SSA, we considered two future scenarios. Scenario 1 assesses 
the species' responses to moderate increases in stressors influencing 
the western fanshell and ``Ouachita'' fanshell populations, although 
current conservation practices would remain in place. Scenario 2 
assesses the species' responses to severe increases in stressors. We 
projected these two scenarios over a 40-year period. We restricted our 
evaluation to 40 years primarily due to limitations projecting non-
modeled, extrapolated future conditions for water quality, road 
density, and habitat fragmentation. A full description of the future 
scenarios and our methods is available in the SSA report (Service 2022, 
pp. 67-72).
    Under Scenario 1, populations of both fanshell species are 
projected to decline in resiliency and redundancy over time as 
conditions moderately decline from current conditions. For western 
fanshell, we project five (45 percent) of the currently extant MUs to 
become extirpated. Of the remaining six populations, four (67 percent) 
would be in medium condition, and two (33 percent) in low condition, 
with no MUs in high condition. For ``Ouachita'' fanshell, we project 
two (50 percent) of the currently extant MUs to become extirpated. Of 
the remaining two populations, one (50 percent) would be in medium 
condition, and one (50 percent) in low condition, with no MUs in high 
condition. Neither species loses any areas of representation although 
redundancy is reduced within the representation units (HUC-4 river 
basins) for both species. However, we do not expect reduced adaptive 
capacity of either species to future environmental change in the next 
40 years.
    While our projections under Scenario 2 do not anticipate additional 
extirpations (and therefore further loss of redundancy) from those 
observed under Scenario 1, we expect all remaining populations of both 
species to be in low condition in 40 years. All extant HUC-4 river 
basins would remain occupied for both species. However, we do not 
expect reduced adaptive capacity of either species to future 
environmental change in the next 40 years.
    We note that, by using the SSA framework to guide our analysis of 
the scientific information documented in the SSA report, we have not 
only analyzed individual effects on the species, but we have also 
analyzed their potential cumulative effects. We incorporate the 
cumulative effects into our SSA analysis when we characterize the 
current and future condition of the species. To assess the current and 
future condition of the species, we undertake an iterative analysis 
that encompasses and incorporates the threats individually and then 
accumulates and evaluates the effects of all the 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.

Determination of Status for the Western Fanshell and ``Ouachita'' 
Fanshell

    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures for determining 
whether a species meets the definition of an endangered species or a 
threatened species. The Act defines an ``endangered species'' as a 
species that is in danger of extinction throughout all or a significant 
portion of its range, and a ``threatened species'' as a species that is 
likely to become an endangered species within the foreseeable future 
throughout all or a significant portion of its range. The Act requires 
that we determine whether a species meets the definition of endangered 
species or threatened species because of any of the following factors: 
(A) The present or threatened destruction, modification, or

[[Page 41736]]

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.
    In conducting our status assessment of the western fanshell and 
``Ouachita'' fanshell, we evaluated all identified threats under the 
Act's section 4(a)(1) factors and assessed how the cumulative impact of 
all threats acts on the viability of the species as a whole. That is, 
all the anticipated effects from both habitat-based and direct 
mortality-based threats are examined in total and then evaluated in the 
context of what those combined negative effects will mean to the 
current and future condition of the western fanshell and ``Ouachita'' 
fanshell. However, for the majority of potential threats, the effect on 
the western fanshell and ``Ouachita'' fanshell (e.g., total losses of 
individual mussels or their habitat) cannot be quantified with 
available information. Instead, we use the best available information 
to gauge the magnitude of each individual threat on the western 
fanshell and ``Ouachita'' fanshell, and then assess how those effects 
combined (and may be ameliorated by any existing regulatory mechanisms 
or conservation efforts) will impact the western fanshell's or 
``Ouachita'' fanshell's current and future viability.
Western Fanshell--Status Throughout All of Its Range
    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the Act's section 4(a)(1) 
factors, we determined that the western fanshell has experienced a 
reduction in populations/MUs from historical conditions. However, the 
species still ranges over three of four major drainages (HUC-4 
representation units) in which it historically occurred. Eleven of 27 
historical MUs are extant. Of those 11, 3 MUs are currently in high 
condition, 3 in medium condition, and 5 in low condition. The majority 
(54 percent) of the MUs are in high or medium condition. Representation 
is maintained with at least one MU in high condition in each of the 3 
extant representation units. With 11 extant MUs across three HUC-4s, 
the species currently retains redundancy to withstand and survive 
potential catastrophic events, although there is no imminent 
catastrophic threat. Therefore, after assessing the best available 
information, we conclude that the species is not currently in danger of 
extinction throughout all of its range.
    However, the following threats currently acting on the western 
fanshell will likely continue into the foreseeable future and decrease 
the condition of the species further over time: water quality 
degradation, altered flow, landscape changes, and habitat fragmentation 
(Factor A). These threats are reasonably expected to be exacerbated by 
continued urbanization, and threats of water quality (temperature) and 
flow are especially exacerbated by climate change (Factor E). These 
threats will continue to impact the species into the foreseeable 
future, and the existing regulatory mechanisms (Factor D) are not 
adequately reducing the impact of these threats on the species. The 
best available data do not indicate that the western fanshell is 
currently impacted at the population level by overutilization for 
commercial, recreational, scientific, or educational purposes (Factor 
B) or predation or disease (Factor C), nor do the best available data 
indicate that the species will be impacted by these factors in the 
future.
    Given the projection of threats 40 years into the future, the 
number of western fanshell populations will decline with the projected 
loss of five MUs, reducing the species' redundancy. Across the 
plausible future scenarios, resiliency also declines with zero to four 
populations projected to be in medium condition and two to six 
populations in low condition. No populations are projected to be in 
high condition in the foreseeable future. Representation is projected 
to remain across the range, but the considerable loss of redundancy and 
resiliency makes the species likely to become in danger of extinction 
in the foreseeable future throughout its range. Thus, after assessing 
the best available information, we conclude that the western fanshell 
is likely to become in danger of extinction within the foreseeable 
future throughout all of its range.
Western Fanshell--Status Throughout a Significant Portion of Its Range
    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. The court in Center for Biological Diversity v. Everson, 435 
F. Supp. 3d 69 (D.D.C. 2020) (Everson), 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'' (Final Policy; 79 FR 37578; July 
1, 2014) that provided if the Services determine that a species is 
threatened throughout all of its range, the Services will not analyze 
whether the species is endangered in a significant portion of its 
range.
    Therefore, we proceed to evaluating whether the species is 
endangered in a significant portion of its range--that is, whether 
there is any portion of the species' range for which both (1) the 
portion is significant; and (2) the species is in danger of extinction 
in that portion. Depending on the case, it might be more efficient for 
us to address the ``significance'' question or the ``status'' question 
first. We can choose to address either question first. Regardless of 
which question we address first, if we reach a negative answer with 
respect to the first question that we address, we do not need to 
evaluate the other question for that portion of the species' range.
    Following the court's holding in Everson, we now consider whether 
there are any significant portions of the species' range where the 
species is in danger of extinction now (i.e., endangered). In 
undertaking this analysis for the western fanshell, we choose to 
address the status question first--we consider information pertaining 
to the geographic distribution of both the species and the threats that 
the species faces to identify any portions of the range where the 
species may be endangered.
    We evaluated the range of the western fanshell to determine if the 
species is in danger of extinction now in any portion of its range. The 
range of a species can theoretically be divided into portions in an 
infinite number of ways. We focused our analysis on portions of the 
species' range that may meet the definition of an endangered species. 
For the western fanshell, we considered whether the threats or their 
effects on the species are greater in any biologically meaningful 
portion of the species' range than in other portions such that the 
species is in danger of extinction now in that portion.
    We examined the following threats: water quality degradation, 
altered flow, landscape changes, and habitat fragmentation, including 
cumulative effects. We evaluated multiple factors--including various 
water quality parameters, land cover data, road density, and barriers--
that contribute to these primary threats. These habitat factors are in 
a medium to high condition across the species' range with the exception 
of the Spring River MU, which has low water quality and low landscape 
conditions. However, overall habitat for the Spring River MU is medium 
condition. Based on this assessment, we found that threats are

[[Page 41737]]

acting similarly within the occupied river basins across the species' 
range. We found no locations where threats are more concentrated in any 
portion of the western fanshell's range at a biologically meaningful 
scale. There are no threats that are having greater impacts on the 
species in any one area. Therefore, there is no biologically meaningful 
portion that has a different status from the overall rangewide status. 
Thus, there are no portions of the species' range where the species has 
a different status from its rangewide status. Therefore, no portion of 
the species' range provides a basis for determining that the species is 
in danger of extinction in a significant portion of its range, and we 
determine that the species is likely to become in danger of extinction 
within the foreseeable future throughout all of its range. This does 
not conflict with the courts' holdings in Desert Survivors v. U.S. 
Department of the Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 
2018) and Center for Biological Diversity v. Jewell, 248 F. Supp. 3d 
946, 959 (D. Ariz. 2017) because, in reaching this conclusion, we did 
not apply the aspects of the Final Policy, including the definition of 
``significant'' that those court decisions held to be invalid.
Western Fanshell--Determination of Status
    Our review of the best available scientific and commercial 
information indicates that the western fanshell meets the Act's 
definition of a threatened species. Therefore, we are listing the 
western fanshell as a threatened species in accordance with sections 
3(20) and 4(a)(1) of the Act.
``Ouachita'' Fanshell--Status Throughout All of Its Range
    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the Act's section 4(a)(1) 
factors, we determined that the ``Ouachita'' fanshell has experienced a 
reduction in resiliency and redundancy from historical conditions. The 
species is extant in four MUs within one major drainage (HUC-4 
representation unit). The species historically occurred in Bayou 
Bartholomew in Louisiana. Of the four extant MUs, one is currently in 
high condition, one in medium condition, and two in low condition. The 
species appears to be endemic to the Ouachita River basin. Although the 
species is known from only one representation unit, half of the extant 
populations are in high or medium condition, maintaining the species' 
representation. The species currently retains redundancy to withstand 
and survive potential catastrophic events, although there is no 
imminent catastrophic threat. Therefore, we determined that the species 
is not currently in danger of extinction throughout all of its range.
    The following threats currently acting on the ``Ouachita'' fanshell 
will likely continue into the foreseeable future and decrease the 
condition of the species further over time: water quality degradation, 
altered flow, landscape changes, and habitat fragmentation (Factor A). 
These threats are reasonably expected to be exacerbated by continued 
urbanization, and threats of water quality (temperature) and flow are 
especially exacerbated by climate change (Factor E). These threats will 
continue to impact the species into the foreseeable future, and the 
existing regulatory mechanisms (Factor D) are not adequately reducing 
the impact of these threats on the species. The best available data do 
not indicate that the ``Ouachita'' fanshell is currently impacted at 
the population level by overutilization for commercial, recreational, 
scientific, or educational purposes (Factor B) or predation or disease 
(Factor C), nor do the best available data indicate that the species 
will be impacted by these factors in the future.
    Given the projection of threats 40 years into the future, the 
number of ``Ouachita'' fanshell populations will decline with the 
projected loss of two MUs, reducing the species' redundancy. Resiliency 
also declines with three to four populations projected to be in low 
condition and zero to one population(s) in medium condition. No 
populations are projected to be in high condition in the foreseeable 
future. As the species occurs in only the Ouachita River basin, 
representation is projected to remain, but the considerable loss of 
redundancy and resiliency makes the species likely to become in danger 
of extinction in the foreseeable future throughout its range. Thus, 
after assessing the best available information, we conclude that the 
``Ouachita'' fanshell is likely to become in danger of extinction 
within the foreseeable future throughout all of its range.
``Ouachita'' Fanshell--Status Throughout a Significant Portion of Its 
Range
    See above, under Western Fanshell--Status Throughout a Significant 
Portion of Its Range, for a description of our evaluation methods and 
our policy application.
    In undertaking the analysis for the ``Ouachita'' fanshell, we 
choose to address the status question first--we consider information 
pertaining to the geographic distribution of both the species and the 
threats that the species faces to identify any portions of the range 
where the species may be endangered. For the ``Ouachita'' fanshell, we 
considered whether the threats or their effects on the species are 
greater in any biologically meaningful portion of the species' range 
than in other portions such that the species is in danger of extinction 
now in that portion.
    We examined the following threats: water quality degradation, 
altered flow, landscape changes, and habitat fragmentation, including 
cumulative effects. We evaluated multiple factors--including various 
water quality parameters, land cover data, road density, and barriers--
that contribute to these primary threats. These habitat factors are in 
a medium to high condition across the species' range with no habitat 
factors in low condition. Based on this assessment, we found that 
threats are acting similarly across the species' range. We found no 
locations where threats are more concentrated in any portion of the 
``Ouachita'' fanshell's range at a biologically meaningful scale. There 
are no threats that are having greater impacts on the species in any 
one area. Therefore, there is no biologically meaningful portion that 
has a different status from the overall rangewide status. Thus, there 
are no portions of the species' range where the species has a different 
status from its rangewide status. Therefore, no portion of the species' 
range provides a basis for determining that the species is in danger of 
extinction in a significant portion of its range, and we determine that 
the species is likely to become in danger of extinction within the 
foreseeable future throughout all of its range. This does not conflict 
with the courts' holdings in Desert Survivors v. U.S. Department of the 
Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 2018) and Center for 
Biological Diversity v. Jewell, 248 F. Supp. 3d 946, 959 (D. Ariz. 
2017) because, in reaching this conclusion, we did not apply the 
aspects of the Final Policy, including the definition of 
``significant'' that those court decisions held to be invalid.
``Ouachita'' Fanshell--Determination of Status
    Our review of the best available scientific and commercial 
information indicates that the ``Ouachita'' fanshell meets the Act's 
definition of a threatened species. Therefore, we are listing the 
``Ouachita'' fanshell as a threatened species in accordance with 
sections 3(20) and 4(a)(1) of the Act.

[[Page 41738]]

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 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 Arkansas Ecological Services Field 
Office for ``Ouachita'' fanshell or Missouri Ecological Services Field 
Office for western fanshell (see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    Once 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 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the States of Arkansas, Kansas, 
Missouri, and Oklahoma will be eligible for Federal funds to implement 
management actions that promote the protection or recovery of the 
western fanshell or ``Ouachita'' fanshell or both species. Information 
on our grant programs that are available to aid species recovery can be 
found at: https://www.fws.gov/service/financial-assistance.
    Please let us know if you are interested in participating in 
recovery efforts for the western fanshell or ``Ouachita'' fanshell. 
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(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is listed as an endangered or 
threatened species and with respect to its critical habitat, if any is 
designated. Regulations implementing this interagency cooperation 
provision of the Act are codified at 50 CFR part 402. Section 7(a)(2) 
of the Act requires Federal agencies to ensure that activities they 
authorize, fund, or carry out are not likely to jeopardize the 
continued existence of any endangered or threatened species or destroy 
or adversely modify its critical habitat. If a Federal action may 
affect a listed species or its critical habitat, the responsible 
Federal agency must enter into consultation with the Service.
    Federal agency actions within the species' habitat that may require 
conference or consultation or both as described in the preceding 
paragraph may include, but are not limited to, management and any other 
landscape-altering activities on Federal lands administered by the 
following agencies:
    (1) U.S. Army Corps of Engineers (channel dredging and maintenance; 
dam projects including flood control, navigation, hydropower, bridge 
projects, stream restoration, and Clean Water Act (33 U.S.C. 1251 et 
seq.) permitting).
    (2) U.S. Department of Agriculture, including the Natural Resources 
Conservation Service and Farm Service Agency (technical and financial 
assistance for projects) and the Forest Service (aquatic habitat 
restoration, fire management plans, fuel reduction treatments, forest 
plans, mining permits).
    (3) U.S. Department of Energy (renewable and alternative energy 
projects).
    (4) Federal Energy Regulatory Commission (interstate pipeline 
construction and maintenance, dam relicensing, and hydrokinetics).
    (5) U.S. Department of Transportation (highway and bridge 
construction and maintenance).
    (6) U.S. Fish and Wildlife Service (issuance of section 10 permits 
for enhancement of survival, HCPs, and SHAs; National Wildlife Refuge 
planning and refuge activities; Partners for Fish and Wildlife program 
projects benefiting these species or other listed species; Wildlife and 
Sportfish Restoration program sportfish stocking).
    (7) Environmental Protection Agency (water quality criteria, 
permitting).
    (8) Office of Surface Mining (land resource management plans, 
mining permits, oil and natural gas permits, renewable energy 
development).
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of a listing on 
proposed and ongoing activities within the range of the listed species. 
The discussion below regarding protective regulations under

[[Page 41739]]

section 4(d) of the Act complies with our policy.

II. Final Rule Issued Under Section 4(d) of the Act

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the Secretary shall issue such regulations as she deems 
necessary and advisable to provide for the conservation of species 
listed as threatened. The U.S. Supreme Court has noted that statutory 
language like ``necessary and advisable'' demonstrates a large degree 
of deference to the agency (see Webster v. Doe, 486 U.S. 592 (1988)). 
Conservation is defined in the Act to mean the use of all methods and 
procedures which are necessary to bring any endangered species or 
threatened species to the point at which the measures provided pursuant 
to the Act are no longer necessary. Additionally, the second sentence 
of section 4(d) of the Act states that the Secretary may by regulation 
prohibit with respect to any threatened species any act prohibited 
under section 9(a)(1), in the case of fish or wildlife, or section 
9(a)(2), in the case of plants. Thus, the combination of the two 
sentences of section 4(d) provides the Secretary with wide latitude of 
discretion to select and promulgate appropriate regulations tailored to 
the specific conservation needs of the threatened species. The second 
sentence grants particularly broad discretion to the Service when 
adopting the prohibitions under section 9.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld rules 
developed under section 4(d) as a valid exercise of agency authority 
where they prohibited take of threatened wildlife or include a limited 
taking prohibition (see Alsea Valley Alliance v. Lautenbacher, 2007 
U.S. Dist. Lexis 60203 (D. Or. 2007); Washington Environmental Council 
v. National Marine Fisheries Service, 2002 U.S. Dist. Lexis 5432 (W.D. 
Wash. 2002)). Courts have also upheld 4(d) rules that do not address 
all of the threats a species faces (see State of Louisiana v. Verity, 
853 F.2d 322 (5th Cir. 1988)). As noted in the legislative history when 
the Act was initially enacted, ``once an animal is on the threatened 
list, the Secretary has an almost infinite number of options available 
to [her] with regard to the permitted activities for those species. 
[She] may, for example, permit taking, but not importation of such 
species, or [s]he may choose to forbid both taking and importation but 
allow the transportation of such species'' (H.R. Rep. No. 412, 93rd 
Cong., 1st Sess. 1973).
    Exercising our authority under section 4(d), we have developed a 
rule that is designed to address the western fanshell's and 
``Ouachita'' fanshell's specific threats and conservation needs. 
Although the statute does not require us to make a ``necessary and 
advisable'' finding with respect to the adoption of specific 
prohibitions under section 9, we find that this rule as a whole 
satisfies the requirement in section 4(d) of the Act to issue 
regulations deemed necessary and advisable to provide for the 
conservation of the western fanshell and ``Ouachita'' fanshell. As 
discussed above under Summary of Biological Status and Threats, we have 
concluded that the western fanshell and ``Ouachita'' fanshell are 
likely to become in danger of extinction within the foreseeable future 
primarily due to water quality degradation, changes to flow, and 
impoundments, which are expected to be exacerbated by continued 
urbanization and effects of climate change.
    The provisions of this 4(d) rule will promote conservation of the 
western fanshell and ``Ouachita'' fanshell by encouraging management of 
the landscape in ways that meet both land management considerations and 
conservation needs of the western fanshell and ``Ouachita'' fanshell. 
The provisions of this rule are one of many tools that the Service will 
use to promote the conservation of the western fanshell and 
``Ouachita'' fanshell.
    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are 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.
    This obligation does not change in any way for a threatened species 
with a species-specific 4(d) rule. Actions that result in a 
determination by a Federal agency of ``not likely to adversely affect'' 
continue to require the Service's written concurrence and actions that 
are ``likely to adversely affect'' a species require formal 
consultation and the formulation of a biological opinion.

Provisions of the 4(d) Rule

    The protective regulations for western fanshell and ``Ouachita'' 
fanshell incorporate prohibitions from section 9(a)(1) of the Act to 
address the threats to the species. In particular, this 4(d) rule will 
provide for the conservation of the western fanshell and ``Ouachita'' 
fanshell by prohibiting the following activities, unless they fall 
within specific exceptions or are otherwise authorized or permitted: 
Importing or exporting; take; possession and other acts with unlawfully 
taken specimens; delivering, receiving, carrying, transporting, or 
shipping in interstate or foreign commerce in the course of commercial 
activity; or selling or offering for sale in interstate or foreign 
commerce.
    As discussed above under Summary of Biological Status and Threats, 
we have concluded that the western fanshell and ``Ouachita'' fanshell 
are likely to become in danger of extinction within the foreseeable 
future primarily due to water quality degradation, changes to flow, and 
impoundments, which are expected to be exacerbated by continued 
urbanization and effects of climate change.
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulation at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Regulating 
take will help preserve the species' remaining populations, slow their 
rate of decline, and decrease synergistic, negative effects from other 
stressors. Therefore, we prohibit take of the western fanshell and 
``Ouachita'' fanshell, except for take resulting from those actions and 
activities specifically excepted by the 4(d) rule.

[[Page 41740]]

    The 4(d) rule provides for the conservation of the species by 
allowing exceptions, including certain standard exceptions, to take 
prohibitions caused by actions and activities that, while they may have 
some minimal level of disturbance to the western fanshell and 
``Ouachita'' fanshell, will not have a negative impact (i.e., will have 
only de minimis impacts) on the species' conservation. The exceptions 
to these prohibitions include incidental take associated with (1) 
Channel and bank restoration projects; (2) silviculture and forest 
management that implements best management practices; and (3) 
transportation projects that avoid instream disturbance in waters 
occupied by the species.
    The first exception is for incidental take resulting from channel 
and bank restoration projects for creation of natural, physically 
stable, ecologically functioning streams, taking into consideration 
connectivity with floodplain and groundwater aquifers. This exception 
includes a requirement that bank restoration projects require planting 
appropriate native vegetation, including woody species appropriate for 
the region and habitat. This exception also includes a requirement for 
surveys and relocation prior to commencement of restoration actions 
(and, if applicable, monitoring after relocation) for western fanshell 
and ``Ouachita'' fanshell that would otherwise be negatively affected 
by the actions. Actions related to restoration activities that would 
negatively affect western fanshell and ``Ouachita'' fanshell include 
individual mussels being removed, dislodged, crushed, and/or killed by 
heavy equipment operations and rip-rap placement; removal, destruction, 
and/or replacement of habitat; increased turbidity from streambed 
disturbance; and alterations to flow and turbidity from permanent 
(weirs) or temporary (causeways) structures needed for construction.
    The second exception is for incidental take resulting from 
silviculture and forest management activities that use State-approved 
best management practices to protect water and sediment quality and 
stream and riparian habitat. Best management practices are designed to 
reduce sedimentation, erosion, and bank destruction, thereby protecting 
instream habitat for these species.
    The third exception is for incidental take resulting from 
transportation projects that do not include activities that disturb 
instream habitat. Bridge designs that include spanning the stream and 
avoiding stream bank disturbance reduce sedimentation and erosion, 
thereby protecting instream habitat for these species.
    In addition, as discussed above under Summary of Changes from the 
Proposed Rule, the 4(d) rule temporarily excepts purposeful take that 
results from capture, handling, and release of western fanshell and 
``Ouachita'' fanshell related to presence/absence surveys, studies to 
document habitat use, and population monitoring by individuals 
permitted to conduct these same activities for other species of mussels 
for a period of 6 months from this final rule's effective date (see 
DATES, above). This provision will allow time for us to process 
applications for amendments to existing permit holders.
    We may issue permits to carry out otherwise prohibited activities, 
including those described above, involving threatened wildlife under 
certain circumstances. Regulations governing permits are codified at 50 
CFR 17.32. With regard to threatened wildlife, a permit may be issued 
for the following purposes: for scientific purposes, to enhance 
propagation or survival, for economic hardship, for zoological 
exhibition, for educational purposes, for incidental taking, or for 
special purposes consistent with the purposes of the Act. The statute 
also contains certain exemptions from the prohibitions, which are found 
in sections 9 and 10 of the Act.
    We recognize the special and unique relationship with our State 
natural resource agency partners in contributing to the conservation of 
listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we must cooperate to the 
maximum extent practicable with the States in carrying out programs 
authorized by the Act. Therefore, any qualified employee or agent of a 
State conservation agency that is a party to a cooperative agreement 
with us in accordance with section 6(c) of the Act, who is designated 
by his or her agency for such purposes, is able to conduct activities 
designed to conserve the western fanshell and ``Ouachita'' fanshell 
that may result in otherwise prohibited take without additional 
authorization.
    Nothing in this 4(d) rule changes in any way the recovery planning 
provisions of section 4(f) of the Act, the consultation requirements 
under section 7 of the Act, or our ability to enter into partnerships 
for the management and protection of the western fanshell and 
``Ouachita'' fanshell. However, interagency cooperation may be further 
streamlined through planned programmatic consultations for the species 
between us and other Federal agencies, where appropriate.

III. Critical Habitat for the Western Fanshell and ``Ouachita'' 
Fanshell

Background

    Section 4(a)(3) of the Act requires that, to the maximum extent 
prudent and determinable, we designate a species' critical habitat 
concurrently with listing the species. 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
    (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).
    This critical habitat designation was proposed when the regulations 
defining ``habitat'' (85 FR 81411; December 16, 2020) and governing the 
4(b)(2) exclusion process for the Service (85 FR 82376; December 18, 
2020) were in place and in effect. However, those two regulations have 
been rescinded (87 FR 37757; June 24, 2022, and 87 FR 43433; July 21, 
2022) and no longer apply to any designations of critical habitat. 
Therefore, for this final rule designating critical habitat for the 
western fanshell and ``Ouachita'' fanshell, we apply the regulations at 
424.19 and the 2016 Joint Policy on 4(b)(2) exclusions (81 FR 7226; 
February 11, 2016).
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures

[[Page 41741]]

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, 
habitat restoration, 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 Federal agencies 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 
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 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. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the Federal agency would be required to consult 
with the Service under section 7(a)(2) of the Act. However, even if the 
Service were to conclude that the proposed activity would 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 and commercial 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 other 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 the 4(d) rule. 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 these 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, HCPs, or other species conservation planning 
efforts if new information available at the time of these planning 
efforts calls for a different outcome.

Physical or Biological Features Essential to the Conservation of the 
Species

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12(b), in determining which areas we will designate as 
critical habitat from within the geographical area occupied by the 
species at the time of listing, we consider the physical or biological 
features that are essential to the conservation of the species and 
which may require special management considerations or protection. The 
regulations at 50 CFR 424.02 define ``physical or biological features 
essential to the conservation of the species'' as the features that 
occur in specific areas and that are essential to support the life-
history needs of the species, including, but not limited to, water 
characteristics, soil type, geological features, sites, prey, 
vegetation, symbiotic species, or other features. A feature may be a 
single habitat characteristic or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity. For example, 
physical features essential to the conservation of the species might 
include gravel of a particular size required for spawning, alkaline 
soil for seed germination, protective cover for migration, or 
susceptibility to flooding or fire that maintains necessary early-
successional habitat characteristics. Biological features might include 
prey species, forage grasses, specific kinds or ages of trees for 
roosting or nesting, symbiotic fungi, or a particular level of 
nonnative species consistent with conservation needs of the listed 
species. The features may also be combinations

[[Page 41742]]

of habitat characteristics and may encompass the relationship between 
characteristics or the necessary amount of a characteristic essential 
to support the life history of the species.
    In considering whether features are essential to the conservation 
of the species, we may consider an appropriate quality, quantity, and 
spatial and temporal arrangement of habitat characteristics in the 
context of the life-history needs, condition, and status of the 
species. These characteristics include, but are not limited to, space 
for individual and population growth and for normal behavior; food, 
water, air, light, minerals, or other nutritional or physiological 
requirements; cover or shelter; sites for breeding, reproduction, or 
rearing (or development) of offspring; and habitats that are protected 
from disturbance.
    As described above under Summary of Biological Status and Threats, 
western fanshell and ``Ouachita'' fanshell occur in large creeks and 
rivers. Occasional or regular interaction among individuals in 
different river reaches not interrupted by a barrier likely occurs, but 
in general, interaction is strongly influenced by habitat fragmentation 
and distance between occupied river or stream reaches. Once released 
from their fish host, freshwater mussels are benthic (bottom-dwelling), 
generally sedentary aquatic organisms and closely associated with 
appropriate habitat patches within a river or stream.
    We derive the specific physical or biological features essential 
for the western fanshell and ``Ouachita'' fanshell from studies of 
these species' (or appropriate surrogate species') habitat, ecology, 
and life history. The primary habitat elements that influence 
resiliency of the western fanshell and ``Ouachita'' fanshell include 
water quality, water quantity, substrate, habitat connectivity, and the 
presence of host fish species to ensure recruitment. These features are 
also described above as species needs under Summary of Biological 
Status and Threats, and a full description is available in the SSA 
reports; the individuals' needs are summarized below in Table 1.

               Table 1--Requirements for Life Stages of Western Fanshell and ``Ouachita'' Fanshell
----------------------------------------------------------------------------------------------------------------
           Life stage                      Resource needs--habitat requirements                 References
----------------------------------------------------------------------------------------------------------------
All Life Stages.................  Water Quality: Naturally clean, high quality water     Allen et al. 2007, pp.
                                   with little or no harmful pollutants (that is,         80-85; Augspurger et
                                   pollutants occur below tolerance limits of mussels,    al. 2003, p. 2569;
                                   fish hosts, prey). The values below are based on the   Bringolf et al. 2007a,
                                   best available science and assume mussels respond to   p. 2094; 2007b, p.
                                   average values of a constituent over time (acute or    2086; Cope et al.
                                   chronic exposure).                                     2008, p. 455; Fuller
                                  [rtarr8] Dissolved oxygen >3 milligrams per liter (mg/  1974, pp. 240-246;
                                   L).                                                    Gillis et al. 2008,
                                  [rtarr8] Low salinity/total dissolved solids.           pp. 140-141; Gray et
                                  [rtarr8] Low nutrient concentrations:                   al. 2002, pp. 155-156;
                                  [rtarr8] Total ammonia nitrogen <0.3-1.0 mg/L at pH     Kolpin et al. 2002,
                                   8.0 and 25 [deg]C.                                     pp. 1208-1210; Spooner
                                                                                          and Vaughn 2008, p.
                                                                                          311; Steingraeber et
                                                                                          al. 2007, p. 297; Wang
                                                                                          et al. 2007a, 2007b,
                                                                                          2010, 2013, entire.
                                     [rtarr8] Nitrate <2.0 mg/L.
                                  [rtarr8] Nitrite <55.8 mg/L.
                                  [rtarr8] Low concentrations of metals:
                                  [rtarr8] Cadmium <0.014 mg/L at 50 mg/L calcium
                                   carbonate (CaCO3) hardness.
                                  [rtarr8] Zinc <0.120 mg/L at 50 mg/L CaCO3 hardness.
                                  [rtarr8] Lead <0.205 mg/L at 50 mg/L CaCO3 hardness.
                                  [rtarr8] Copper <0.005 mg/L in moderately hard water.
                                  [rtarr8] Natural, unaltered ambient water temperature
                                   generally <27 [deg]C.
                                  Water Quantity: Flowing water in sufficient quantity   Galbraith and Vaughn
                                   to support the life-history requirements of mussels    2009, p. 46; Allen and
                                   and their fish hosts.                                  Vaughn 2010, p. 390;
                                                                                          Peterson et al. 2011,
                                                                                          p. 115; Daraio et al.
                                                                                          2010, p. 838.
Gamete (sperm, egg development,   [rtarr8] Sexually mature males and females with        Haag 2012, pp. 38-39;
 fertilization) Glochidia.         appropriate water temperatures for spawning,           Galbraith and Vaughn
                                   fertilization, and brooding.                           2009, pp. 45-46;
                                  [rtarr8] Presence of fish hosts (of appropriate         Barnhart et al. 2008,
                                   species) with sufficient flow to allow attachment,     p. 372.
                                   encystment, relocation, excystment, and dispersal of
                                   glochidia.
Juvenile, sub-adult, and adult    [rtarr8] Stable substrate comprised of mixed sand,     Allen and Vaughn 2010,
 (from excyst- ment to maturity).  gravel and cobble, and appropriate for burrowing,      pp. 384-385; Haag
                                   pedal feeding, and survival.                           2012, pp. 26-42;
                                  [rtarr8] Appropriate food sources (phytoplankton,       Eckert 2003, pp. 18-
                                   zooplankton, protozoans, detritus, dissolved organic   19, 33.
                                   matter) in adequate supply.
                                  [rtarr8] Presence and abundance of fish hosts
                                   available for recruitment.
----------------------------------------------------------------------------------------------------------------

Summary of Essential Physical or Biological Features

    We derive the specific physical or biological features essential to 
the conservation of the western fanshell and ``Ouachita'' fanshell from 
studies of the species' habitat, ecology, and life history as described 
below. Additional information can be found in chapter 2 of the SSA 
report (Service 2022, pp. 9-16), which is available on https://www.regulations.gov under Docket No. FWS-R3-ES-2021-0061. We have 
determined that the following physical or biological features are 
essential to the conservation of western fanshell and ``Ouachita'' 
fanshell:
    (1) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species are found and to maintain stream connectivity, specifically 
providing for the exchange of nutrients and sediment for maintenance of 
the mussels' and fish hosts' habitat and food availability, maintenance 
of spawning habitat for native host fishes, and the ability for newly 
transformed juveniles to settle and become established in their 
habitats. Adequate flows ensure delivery of oxygen, enable 
reproduction, deliver food to filter-feeding mussels, and reduce 
contaminants and fine sediments from interstitial spaces.
    (2) Suitable substrates and connected instream habitats, 
characterized by geomorphically stable stream channels and banks (that 
is, channels that maintain lateral dimensions,

[[Page 41743]]

longitudinal profiles, and sinuosity patterns over time without an 
aggrading or degrading bed elevation) with habitats that support a 
diversity of freshwater mussel and native fish (such as stable riffle-
run-pool habitats that provide flow refuges consisting of silt-free 
gravel and coarse sand substrates).
    (3) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including, but not limited to: dissolved oxygen 
(generally above 3 parts per million (ppm)) and water temperature 
(generally below 80 degrees Fahrenheit ([deg]F) (27 degrees Celsius 
([deg]C)). Additionally, water and sediment should be low in ammonia 
(generally below 1.0 ppm total ammonia-nitrogen) and heavy metals, and 
lack excessive total suspended solids and other pollutants.
    (4) The presence and abundance of fish hosts necessary for 
recruitment of the western fanshell and ``Ouachita'' fanshell. For the 
western fanshell, this includes logperch (Percina caprodes), rainbow 
darter (Etheostoma caeruleum), slenderhead darter (Percina 
phoxocephala), fantail darter (Etheostoma flabellare), or orangebelly 
darter (Etheostoma radiosum). For the ``Ouachita'' fanshell, this 
includes logperch (Percina caprodes), slenderhead darter (Percina 
phoxocephala), or orangebelly darter (Etheostoma radiosum).

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features which are essential to the conservation of 
the species and which may require special management considerations or 
protection.
    The features essential to the conservation of the western fanshell 
and ``Ouachita'' fanshell may require special management considerations 
or protections to reduce the following threats: (1) Alteration of the 
natural flow regime (modifying the natural hydrograph and seasonal 
flows), including water withdrawals, resulting in flow reduction and 
available water quantity; (2) urbanization of the landscape, including 
(but not limited to) land conversion for urban and commercial use, 
infrastructure (pipelines, roads, bridges, utilities), and urban water 
uses (resource extraction activities, water supply reservoirs, 
wastewater treatment, etc.); (3) significant alteration of water 
quality and nutrient pollution from a variety of activities, such as 
industrial and municipal effluents, mining, and agricultural 
activities; (4) land use activities that remove large areas of forested 
wetlands and riparian systems; (5) dam construction and culvert and 
pipe installation that create barriers to movement for the western 
fanshell and ``Ouachita'' fanshell, or their host fishes; (6) changes 
and shifts in seasonal precipitation patterns as a result of climate 
change; and (7) other watershed and floodplain disturbances that 
release sediments, pollutants, or nutrients into the water.
    Management activities that could ameliorate these threats include, 
but are not limited to: Use of best management practices designed to 
reduce sedimentation, erosion, and bank destruction; protection of 
riparian corridors and woody vegetation; moderation of surface and 
ground water withdrawals to maintain natural flow regimes; improved 
stormwater management; and reduction of other watershed and floodplain 
disturbances that release sediments, pollutants, or nutrients into the 
water.
    In summary, we find that the occupied areas we are designating as 
critical habitat contain the physical or biological features that are 
essential to the conservation of the species and which may require 
special management considerations or protection. Special management 
considerations or protection may be required of the Federal action 
agency to eliminate, or to reduce to negligible levels, the threats 
affecting the physical and biological features of each unit.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available to designate critical habitat. In accordance 
with the Act and our implementing regulations at 50 CFR 424.12(b), we 
review available information pertaining to the habitat requirements of 
the species and identify specific areas within the geographical area 
occupied by the species at the time of listing and any specific areas 
outside the geographical area occupied by the species to be considered 
for designation as critical habitat. We are not designating any areas 
outside the geographical area occupied by the western fanshell or 
``Ouachita'' fanshell because we have not identified any unoccupied 
areas that meet the definition of critical habitat. We have determined 
that occupied areas are sufficient to conserve these species.
Methodology Used For Selection of Units
    First, we included current populations with high or medium 
resiliency. These populations show recruitment or varied age class 
structure and could be used for recovery actions to augment other 
populations through propagation activities or direct translocations 
within their basins. We defined a population as ``current'' if it 
contains live or recent dead individuals observed in surveys from 2000 
to present (Service 2022, p. 22).
    Second, we evaluated spatial representation and redundancy across 
the species' ranges, to include last remaining population(s) in major 
river basins.
    Third, we examined the overall contribution of populations in low 
condition and threats to those populations. We considered adjacency and 
connectivity to high and medium populations, as well as isolated 
populations with potentially important genetic or adaptive traits, and 
we did not include populations that have potentially low likelihood of 
recovery due to low abundance and limited distribution or populations 
currently under high levels of threats.
    Sources of data for these critical habitat designations include 
information from State agencies throughout the species' ranges and 
numerous survey reports on streams throughout the species' ranges 
(Service 2022, entire). We have also reviewed available information 
that pertains to the habitat requirements of these species. Sources of 
information on habitat requirements include studies conducted at 
occupied sites and published in peer-reviewed articles, agency reports, 
and data collected during monitoring efforts (Service 2022, entire).
    In summary, for areas within the geographic area occupied by these 
species at the time of listing, we delineated critical habitat unit 
boundaries using a precise set of criteria. Specifically, we identified 
river and stream reaches with observations from 2000 to present. We 
determined it is reasonable to find these areas occupied, given the 
variable data associated with timing and frequency of mussel surveys 
conducted throughout the species' ranges and available State heritage 
databases, and information supports the likelihood of both species' 
continued presence in these areas within this timeframe. Specific 
habitat areas were delineated, based on Natural Heritage Element 
Occurrences, published reports, and unpublished

[[Page 41744]]

survey data provided by States. These areas provide habitat for western 
fanshell and ``Ouachita'' fanshell populations and are large enough to 
be self-sustaining over time, despite fluctuations in local conditions. 
The areas within the critical habitat units represent continuous river 
and stream reaches of free-flowing habitat patches capable of 
sustaining host fishes and allowing for seasonal transport of 
glochidia, which are essential for reproduction and dispersal of 
western fanshell and ``Ouachita'' fanshell.
    We consider portions of the following rivers and streams to be 
occupied by these species at the time of listing, and appropriate for 
critical habitat designation:
    (1) Western fanshell--Black River, Fall River, Middle Fork Little 
Red River, St. Francis River, South Fork Spring River, Spring River, 
Strawberry River, and Verdigris River (see Final Critical Habitat 
Designation, below).
    (2) ``Ouachita'' fanshell--Little Missouri River, Ouachita River, 
and Saline River (see Final Critical Habitat Designation, below).
Critical Habitat Maps
    When determining critical habitat boundaries, we made every effort 
to avoid including developed areas, such as lands covered by buildings, 
pavement, and other structures, because such lands lack physical or 
biological features necessary for the western fanshell and ``Ouachita'' 
fanshell. The scale of the maps we prepared under the parameters for 
publication within the Code of Federal Regulations may not reflect the 
exclusion of such developed lands. Any such lands inadvertently left 
inside critical habitat boundaries shown on the maps of this rule have 
been excluded by text in the rule and are not designated as critical 
habitat. Therefore, a Federal action involving these lands will not 
trigger section 7 consultation under the Act with respect to critical 
habitat and the requirement of no adverse modification unless the 
specific action will affect the physical or biological features in the 
adjacent critical habitat.
    We are designating as critical habitat stream reaches that we have 
determined are occupied at the time of listing (i.e., currently 
occupied) and that contain one or more of the physical or biological 
features that are essential to support life-history processes of the 
species. Six units for the western fanshell and three units for the 
``Ouachita'' fanshell are designated based on the presence of the 
physical or biological features that support the western fanshell's or 
``Ouachita'' fanshell's life-history processes. Some units contain all 
of the identified physical or biological features and support multiple 
life-history processes. Some units contain only some of the physical or 
biological features necessary to support the western fanshell's or 
``Ouachita'' fanshell's particular use of that habitat.
    The critical habitat designation is defined by the map or maps, as 
modified by any accompanying regulatory text, presented at the end of 
this document under Regulation Promulgation. We include more detailed 
information on the boundaries of the critical habitat designation in 
the discussion of individual units below. We will make the coordinates 
or plot points or both on which each map is based available to the 
public on https://www.regulations.gov at Docket No. FWS-R3-ES-2021-
0061, and on our internet sites at https://www.fws.gov/species/western-fanshell-cyprogenia-aberti for western fanshell and https://www.fws.gov/species/ouachita-fanshell-cyprogenia-sp-cf-aberti for 
``Ouachita'' fanshell.

Final Critical Habitat Designation

    We are designating a total of 261.4 river miles (river mi) (420.7 
kilometers (km)) in 6 units as critical habitat for the western 
fanshell and a total of 227.7 river mi (366.5 km) in 3 units as 
critical habitat for the ``Ouachita'' fanshell. All units are occupied 
by their respective species. The critical habitat areas we describe 
below constitute our current best assessment of areas that meet the 
definition of critical habitat for the western fanshell and 
``Ouachita'' fanshell. The six areas designated as critical habitat for 
the western fanshell are: Upper Black River (Unit WF 1), Lower Black/
Strawberry River (Unit WF 2), St. Francis River (Unit WF 5), South Fork 
Spring River (Unit WF 6), Spring River (AR) (Unit WF 7), and Spring 
River (MO) (Unit WF 8). The three areas designated as critical habitat 
for the ``Ouachita'' fanshell are: Little Missouri River (Unit OF 1), 
Ouachita River (Unit OF 3), and Saline River (Unit OF 4). For both the 
western fanshell and ``Ouachita'' fanshell, unit numbers are not 
sequential because of exclusions we are making in this final rule; see 
Exclusions Based on Other Relevant Impacts, below, for more 
information. Tables 2 and 3 show the critical habitat units and the 
approximate river miles of each unit.

        Table 2--Critical Habitat Units for the Western Fanshell
      [Area estimates reflect all land within critical habitat unit
                               boundaries]
------------------------------------------------------------------------
                                   Adjacent riparian
      Critical habitat unit        land ownership by      River miles
                                          type            (kilometers)
------------------------------------------------------------------------
WF 1. Upper Black River.........  Public (Federal,             13.7 (22)
                                   State).                     51 (82.1)
                                  Private............
WF 2. Lower Black/Strawberry      Public (State).....        10.9 (17.5)
 River.                           Private............      100.4 (161.6)
WF 5. St. Francis River.........  Public (Federal,           12.6 (20.2)
                                   State).                   36.7 (59.1)
                                  Private............
WF 6. South Fork Spring River...  Private............        13.4 (21.6)
WF 7. Spring River (AR).........  Private............        14.2 (22.9)
WF 8. Spring River (MO).........  Private............         8.5 (13.7)
                                                      ------------------
    Totals......................  Public.............        37.2 (59.7)
                                  Private............        224.2 (361)
                                                      ------------------
                                     Total...........      261.4 (420.7)
------------------------------------------------------------------------
Note: River miles may not sum due to rounding.


[[Page 41745]]


      Table 3--Critical Habitat Units for the ``Ouachita'' Fanshell
      [Area estimates reflect all land within critical habitat unit
                               boundaries]
------------------------------------------------------------------------
                                   Adjacent riparian
      Critical habitat unit        land ownership by      River miles
                                          type            (kilometers)
------------------------------------------------------------------------
OF 1. Little Missouri River.....  Private............        22.9 (36.9)
OF 3. Ouachita River............  Private............        53.5 (86.1)
OF 4. Saline River..............  Public (State).....          0.5 (0.8)
                                  Private............      150.8 (242.7)
                                                      ------------------
    Totals......................  Public.............          0.5 (0.8)
                                  Private............      227.2 (365.7)
                                                      ------------------
                                     Total...........      227.7 (366.5)
------------------------------------------------------------------------
Note: River miles may not sum due to rounding.

    We present brief descriptions of all units and reasons why they 
meet the definition of critical habitat for the western fanshell or 
``Ouachita'' fanshell, below.
WF 1: Upper Black River
    Unit WF 1 consists of 64.7 river mi (104.1 km) of Black River in 
Butler and Wayne Counties, Missouri, from Clearwater Dam southwest of 
Piedmont, Wayne County, extending downstream to Butler County Road 658 
crossing southeast of Poplar Bluff, Butler County. Unit WF 1 includes 
the river channel up to the ordinary high water mark. Riparian lands 
that border the unit include approximately 51 river mi (82.1 km; 79 
percent) in private ownership and 13.7 river mi (22 km; 21 percent) in 
public (Federal or State) ownership. Approximately 2.7 miles of the 
public ownership in this unit are State lands associated with Missouri 
Department of Conservation's (MDC) Bradley A. Hammer Memorial 
Conservation Area, Dan River Access, Hilliard Access, and Stephen J. 
Sun Conservation Area. Eleven miles are Federal land associated with 
the U.S. Forest Service's (USFS) Mark Twain National Forest and U.S. 
Army Corps of Engineers (USACE) Clearwater Recreation Area. General 
land use within the adjacent riparian areas of this unit includes 
forest, agriculture, several State-managed game lands, the town of Mill 
Spring, and city of Poplar Bluff. Clearwater Dam is operated by the 
USACE. Unit WF 1 is occupied by the species and contains all of the 
physical or biological features essential to the conservation of the 
species. This unit does not overlap with any designated critical 
habitat for other listed species.
    Threats identified within the unit include degradation of habitat 
and water quality from impoundments, channelization, and point and 
nonpoint source water pollution, including siltation and pollution 
associated with agriculture, development, and wastewater treatment 
plants. Special management considerations or protection measures to 
reduce or alleviate the threats may include reducing water quality 
degradation and habitat loss associated with agriculture, development, 
and wastewater treatment plants (see Special Management Considerations 
or Protection, above).
WF 2: Lower Black/Strawberry River
    Unit WF 2 consists of 111.3 river mi (179.1 km) of Black River and 
Strawberry River in Independence, Jackson, Lawrence, and Sharp Counties 
in Arkansas. Unit WF 2 includes the river channel up to the ordinary 
high water mark. Black River makes up 54.6 river mi (87.9 km) from the 
mouth of Spring River northeast of Black Rock, extending downstream to 
the mouth of Strawberry River northeast of Dowdy, Independence County, 
Arkansas. Strawberry River makes up 56.7 river mi (91.2 km) from the 
mouth of Lave Creek north of Evening Shade, Sharp County, extending 
downstream to the confluence with Black River northeast of Dowdy, 
Independence County, Arkansas. Riparian lands that border the unit 
include approximately 100.4 river mi (161.6 km; 90 percent) in private 
ownership and 10.9 river mi (17.5 km; 10 percent) in public (State) 
ownership. The public land ownership in this unit is associated with 
Arkansas Game and Fish Commission's Shirey Bay Rainey Brake Wildlife 
Management Area on Black River. The Nature Conservancy's Strawberry 
River Preserve and Ranch on Strawberry River is also in this unit. 
General land use within the adjacent riparian areas of this unit 
includes forest, agriculture, State-managed game lands, the town of 
Powhatan, and city of Black Rock. Unit WF 2 is occupied by the species 
and contains one or more of the physical or biological features 
essential to the species' conservation. There is overlap of 70.3 river 
mi (113.1 km) of this unit with designated critical habitat for 
rabbitsfoot (Quadrula cylindrica cylindrica) (see 50 CFR 17.95(f) and 
80 FR 24692, April 30, 2015).
    Threats identified within the unit include degradation of habitat 
and water quality from impoundments, channelization, and point and 
nonpoint source water pollution, including siltation and pollution 
associated with agriculture, development, unpaved roads, and wastewater 
treatment plants. Special management considerations or protection 
measures to reduce or alleviate the threats may include reducing water 
quality degradation and habitat loss associated with agriculture, 
development, and wastewater treatment plants (see Special Management 
Considerations or Protection, above).
WF 5: St. Francis River
    Unit WF 5 consists of 49.3 river mi (79.3 km) of St. Francis River 
in Madison and Wayne Counties, Missouri, extending from the mouth of 
Wachita Creek west of Fredericktown, Madison County, downstream to the 
mouth of Big Creek northwest of Silva, Wayne County. Unit WF 5 includes 
the river channel up to the ordinary high water mark. Riparian lands 
that border the unit include approximately 36.7 river mi (59.1 km; 74 
percent) in private ownership and 12.6 river mi (20.2 km; 26 percent) 
in public (Federal or State) ownership. Approximately 2.4 river mi of 
the public ownership in this unit are State lands associated with MDC's 
Coldwater Conservation Area, Mill Stream Gardens, and Roselle Access. 
Ten miles are Federal land associated with the USFS's Mark Twain 
National Forest. General land use within the adjacent riparian areas of 
this unit is predominantly forest and pasture with isolated occurrences 
of developed areas. Unit WF 5 is occupied by the species and contains 
one or more of the physical or biological features essential

[[Page 41746]]

to the species' conservation. Unit WF 5 entirely overlaps with 
designated critical habitat for rabbitsfoot (see 50 CFR 17.95(f) and 80 
FR 24692, April 30, 2015).
    Threats identified within the unit include degradation of habitat 
and water quality from impoundments and point and nonpoint source water 
pollution, including siltation and pollution associated with 
development, unpaved roads, and wastewater treatment plants. Special 
management considerations or protection measures to reduce or alleviate 
the threats may include reducing water quality degradation and habitat 
loss associated with agriculture, development, and wastewater treatment 
plants (see Special Management Considerations or Protection, above).
WF 6: South Fork Spring River
    Unit WF 6 consists of 13.4 river mi (21.6 km) of South Fork Spring 
River in Fulton County, Arkansas, from the mouth of Camp Creek east of 
Salem, Fulton County, extending downstream to the Arkansas Highway 289 
crossing northwest of Cherokee Village in Fulton County. Unit WF 6 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership. General land use within the adjacent riparian 
areas of this unit is predominantly forest, agriculture, and pasture 
with isolated occurrences of developed areas. Unit WF 6 is occupied by 
the species and contains one or more of the physical or biological 
features essential to the species' conservation. This unit does not 
overlap with any designated critical habitat for other listed species.
    Threats identified within the unit include degradation of habitat 
and water quality from point and nonpoint source water pollution, 
including siltation and pollution associated with agriculture, 
development, unpaved roads, and wastewater treatment plants. Special 
management considerations or protection measures to reduce or alleviate 
the threats may include reducing water quality degradation and habitat 
loss associated with agriculture, development, and wastewater treatment 
plants (see Special Management Considerations or Protection, above).
WF 7: Spring River (AR)
    Unit WF 7 consists of 14.2 river mi (22.9 km) of Spring River in 
Lawrence and Randolph Counties, Arkansas, from the mouth of Wells Creek 
at Ravenden, extending downstream to the mouth of Stennitt Creek 
southeast of Imboden, Lawrence County. Unit WF 7 includes the river 
channel up to the ordinary high water mark. Approximately 100 percent 
of the riparian lands that border the unit are in private ownership. 
General land use within the adjacent riparian areas of this unit 
includes forest, agriculture, pasture, and the towns of Imboden and 
Ravenden. Unit WF 7 is occupied by the species and contains one or more 
of the physical or biological features essential to the species' 
conservation. Unit WF 7 entirely overlaps with designated critical 
habitat for rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 
2015).
    Threats identified within the unit include degradation of habitat 
and water quality from point and nonpoint source water pollution, 
including siltation and pollution associated with agriculture, 
development, unpaved roads, and wastewater treatment plants. Special 
management considerations or protection measures to reduce or alleviate 
the threats may include reducing water quality degradation and habitat 
loss associated with agriculture, development, and wastewater treatment 
plants (see Special Management Considerations or Protection, above).
WF 8: Spring River (MO)
    Unit WF 8 consists of 8.5 river mi (13.7 km) of Spring River in 
Jasper County, Missouri, from the mouth of North Fork Spring River east 
of Asbury, Jasper County, Missouri, extending downstream to the Kansas 
State line, then from where it re-enters Missouri to the mouth of 
Center Creek west of Carl Junction, Jasper County, Missouri. Unit WF 8 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership. General land use within the adjacent riparian 
areas of this unit is predominantly forest, agriculture, and pasture, 
with isolated occurrences of developed areas. Unit WF 8 is occupied by 
the species and contains one or more of the physical or biological 
features essential to the species' conservation. Unit WF 8 entirely 
overlaps with designated critical habitat for Neosho mucket and 
rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015).
    Threats identified within the unit include degradation of habitat 
and water quality from point and nonpoint source water pollution, 
including siltation and pollution associated with agriculture, 
development, unpaved roads, wastewater treatment plants, and historical 
heavy metal mining. Special management considerations or protection 
measures to reduce or alleviate the threats may include reducing water 
quality degradation and habitat loss associated with agriculture, 
development, wastewater treatment plants, and heavy metal contamination 
(see Special Management Considerations or Protection, above).
    In our March 3, 2022, proposed rule, we proposed Unit WF 8 as 
including 15 river mi (24.1 km) of Spring River in Jasper County, 
Missouri, and Cherokee County, Kansas. The Kansas Agreement covers 6.5 
river miles (10.5 km) of the proposed Unit WF 8, and we have excluded 
that portion of the proposed unit from this final designation (see 
Exclusions Based on Other Relevant Impacts, below).
OF 1: Little Missouri River
    Unit OF 1 consists of 22.9 river mi (36.9 km) of Little Missouri 
River in Clark, Nevada, and Ouachita Counties, Arkansas, from the mouth 
of Garland Creek northeast of Prescott, Nevada County, downstream to 
the mouth of Horse Branch north of Red Hill, Ouachita County. Unit OF 1 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership. General land use within the adjacent riparian 
areas of this unit includes forest and agriculture. Unit OF 1 is 
occupied by the species and contains one or more of the physical or 
biological features essential to the species' conservation. This unit 
does not overlap with any designated critical habitat for other listed 
species.
    Threats identified within the unit include dams, impoundments, and 
point and nonpoint source water pollution, including siltation and 
pollution associated with a variety of land uses. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include reducing water quality degradation and habitat loss 
and fragmentation (see Special Management Considerations or Protection, 
above).
OF 3: Ouachita River
    Unit OF 3 consists of 53.5 river mi (86.1 km) of Ouachita River in 
Clark, Dallas, and Ouachita Counties, Arkansas, from the mouth of L'Eau 
Frais Creek southeast of Arkadelphia, Clark County, downstream to the 
mouth of Ecore Fabre Bayou north of Camden, Ouachita County. Unit OF 3 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership. There is a Wetlands Reserve Program easement 
within the unit. General land use within the adjacent riparian areas of 
this unit

[[Page 41747]]

includes forest, agriculture, and pasture. Unit OF 3 is occupied by the 
species and contains one or more of the physical or biological features 
essential to the species' conservation. There is overlap of 22.8 river 
mi (36.7 km) of this unit with designated critical habitat for 
rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015).
    Threats identified within the unit include dams, impoundments, and 
point and nonpoint source water pollution, including siltation and 
pollution associated with a variety of land uses. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include reducing water quality degradation and habitat loss 
and fragmentation (see Special Management Considerations or Protection, 
above).
OF 4: Saline River
    Unit OF 4 consists of 151.3 river mi (243.5 km) of Saline River in 
Ashley, Bradley, Cleveland, Dallas, Drew, and Grant Counties, Arkansas, 
from U.S. Highway 270 east of Poyen, Grant County, downstream to the 
mouth of Mill Creek north of Stillions, Ashley County. Unit OF 4 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership and less than 1 percent is in public 
ownership. The public ownership in this unit is State-owned land 
associated with Jenkins Ferry State Park. General land use within the 
adjacent riparian areas of this unit includes forest, agriculture, 
pasture, the town of Tull, and city of Benton. Unit OF 4 is occupied by 
the species and contains one or more of the physical or biological 
features essential to the species' conservation. There is overlap of 
74.2 river mi (119.4 km) of this unit with designated critical habitat 
for the rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 
2015).
    Threats identified within the unit include dams, impoundments, 
mining, development, and point and nonpoint source water pollution, 
including siltation and pollution associated with development in the 
headwaters and a variety of other land uses. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include reducing water quality degradation and habitat loss 
and fragmentation (see Special Management Considerations or Protection, 
above).
    In our March 3, 2022, proposed rule, we proposed Unit OF 4 as 
including 185.3 river mi (298.2 km) of Saline River in Ashley, Bradley, 
Cleveland, Dallas, Drew, Grant, and Saline Counties, Arkansas. The 
Headwaters Agreement covers 34.1 river miles (54.9 km) of the proposed 
Unit OF 4, and we have excluded that portion of the proposed unit from 
this final designation (see Exclusions Based on Other Relevant Impacts, 
below).

Effects of Critical Habitat Designation

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

[[Page 41748]]

Application of the ``Adverse Modification'' Standard
    The key factor related to the destruction or adverse modification 
determination is whether implementation of the proposed Federal action 
directly or indirectly alters the designated critical habitat in a way 
that appreciably diminishes the value of the critical habitat as a 
whole for the conservation of the listed species. As discussed above, 
the role of critical habitat is to support physical or biological 
features essential to the conservation of a listed species and provide 
for the conservation of the species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may violate section 
7(a)(2) of the Act by destroying or adversely modifying such habitat, 
or that may be affected by such designation.
    Activities that we may, during a consultation under section 7(a)(2) 
of the Act, consider likely to destroy or adversely modify critical 
habitat include, but are not limited to, actions that would: (1) Alter 
the geomorphology of the species' stream and river habitats (for 
example, instream excavation or dredging, impoundment, channelization, 
sand and gravel mining, clearing riparian vegetation, and discharge of 
fill materials); (2) significantly alter the existing flow regime where 
these species occur (for example, impoundment, urban development, water 
diversion, water withdrawal, water draw-down, and hydropower 
generation); (3) significantly alter water chemistry or water quality 
(for example, hydropower discharges, or the release of chemicals, 
biological pollutants, or heated effluents into surface water or 
connected groundwater at a point source or by dispersed release 
(nonpoint source)); or (4) significantly alter streambed material 
composition and quality by increasing sediment deposition or 
filamentous algal growth (for example, construction projects, gravel 
and sand mining, oil and gas development, coal mining, livestock 
grazing, irresponsible logging practices, and other watershed and 
floodplain disturbances that release sediments or nutrients into the 
water).

Exemptions

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

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

    Section 4(b)(2) of the Act states that the Secretary shall 
designate and make revisions to critical habitat on the basis of the 
best available scientific data after taking into consideration the 
economic impact, national security impact, and any other relevant 
impact of specifying any particular area as critical habitat. The 
Secretary may exclude an area from critical habitat based on economic 
impacts, impacts on national security, or any other relevant impacts. 
Exclusion decisions are governed by the regulations at 50 CFR 424.19 
and the Policy Regarding Implementation of Section 4(b)(2) of the 
Endangered Species Act (2016 Policy; 81 FR 7226, February 11, 2016)--
both of which were developed jointly with National Marine Fisheries 
Service (NMFS). We also refer to a 2008 Department of the Interior 
Solicitor's opinion entitled, ``The Secretary's Authority to Exclude 
Areas from a Critical Habitat Designation under Section 4(b)(2) of the 
Endangered Species Act'' (M-37016). We explain each decision to exclude 
areas, as well as decisions not to exclude, to demonstrate that the 
decision is reasonable.
    The Secretary may exclude any particular area if she determines 
that the benefits of such exclusion outweigh the benefits of including 
such area as part of the critical habitat, unless she determines, based 
on the best scientific data available, that the failure to designate 
such area as critical habitat will result in the extinction of the 
species. In making the determination to exclude a particular area, the 
statute on its face, as well as the legislative history, are clear that 
the Secretary has broad discretion regarding which factor(s) to use and 
how much weight to give to any factor.
    We describe below the process that we undertook for deciding 
whether to exclude any areas--taking into consideration each category 
of impacts and our analyses of the relevant impacts.
Exclusions Based on Economic Impacts
    Section 4(b)(2) of the Act and its implementing regulations require 
that we consider the economic impact that may result from a designation 
of critical habitat. In order to consider economic impacts, we prepared 
an incremental effects memorandum (IEM) and screening analysis which, 
together with our narrative and interpretation of effects, we consider 
our economic analysis of the critical habitat designation and related 
factors (Service 2021, entire). The analysis, dated March 19, 2021, was 
made available for public review from March 3, 2022, through May 2, 
2022 (87 FR 12338; March 3, 2022). The economic analysis addressed 
probable economic impacts of critical habitat designation for the 
western fanshell and ``Ouachita'' fanshell. Following the close of the 
comment period, we reviewed and evaluated all information submitted 
during the comment period that may pertain to our consideration of the 
probable incremental economic impacts of this critical habitat 
designation. Additional information relevant to the probable 
incremental economic impacts of critical habitat designation for the 
western fanshell and ``Ouachita'' fanshell is summarized below and 
available in the screening analysis for the species (Industrial 
Economics, Inc. 2021, entire), available at https://www.regulations.gov.
    Executive Orders (E.O.s) 12866 and 13563 direct Federal agencies to 
assess the costs and benefits of available regulatory alternatives in 
quantitative (to the extent feasible) and qualitative terms. Consistent 
with the E.O. regulatory analysis requirements, our effects analysis 
under the Act may take into consideration impacts to both directly and 
indirectly affected entities, where practicable and reasonable. If 
sufficient data are available, we assess, to the extent practicable, 
the probable impacts to both directly and indirectly affected entities. 
As part of our screening analysis, we considered the types of economic 
activities that are likely to occur within the areas likely affected by 
the critical habitat designation. In our evaluation of the probable 
incremental economic impacts that may result from the designation of 
critical habitat for the western fanshell and ``Ouachita'' fanshell, 
first we identified, in the IEM dated February 1, 2021 (Service 2021, 
entire), probable incremental economic impacts associated with the 
following categories of activities: Instream excavation or dredging; 
impoundments; channelization; sand and gravel mining;

[[Page 41749]]

clearing riparian vegetation; discharge of fill materials; urban 
development; water diversion; water withdrawal; water draw-down; 
hydropower generation and discharges; release of chemicals, biological 
pollutants, or heated effluents into surface water or connected ground 
water at a point source or by dispersed release (nonpoint); 
construction projects; oil and gas development; coal mining; livestock 
grazing; timber harvest; and other watershed or floodplain activities 
that release sediments or nutrients into the water. We considered each 
industry or category individually. Additionally, we considered whether 
their activities have any Federal involvement.
    Critical habitat designation generally will not affect activities 
that do not have any Federal involvement; under the Act, the 
designation of critical habitat affects activities conducted, funded, 
permitted, or authorized by Federal agencies only. In areas where the 
western fanshell or ``Ouachita'' fanshell are present, Federal agencies 
are required to consult with the Service under section 7 of the Act on 
activities they fund, permit, or implement that may affect the species. 
Consultations to avoid the destruction or adverse modification of 
critical habitat will be incorporated into the existing consultation 
process.
    In our IEM, we attempted to clarify the distinction between the 
effects that would result from the species being listed and those 
attributable to the critical habitat designation (i.e., difference 
between the jeopardy and adverse modification standards) for the 
western fanshell's and ``Ouachita'' fanshell's critical habitat. 
Because we are designating critical habitat for the western fanshell 
and ``Ouachita'' fanshell concurrently with listing the species, it has 
been our experience that it is more difficult to discern which 
conservation efforts are attributable to the species' being listed and 
those which will result solely from the designation of critical 
habitat; this is particularly difficult where there is no unoccupied 
critical habitat and, thus, there will be consultations for all areas 
based on the species' presence in those areas. However, the following 
specific circumstances in this case help to inform our evaluation: (1) 
The essential physical or biological features identified for critical 
habitat are the same features essential for the life requisites of the 
species, and (2) any actions that would result in sufficient harm or 
harassment to constitute jeopardy to the western fanshell or 
``Ouachita'' fanshell would also likely adversely affect the essential 
physical or biological features of critical habitat. The IEM outlines 
our rationale concerning this limited distinction between baseline 
conservation efforts and incremental impacts of the designation of 
critical habitat for this species. This evaluation of the incremental 
effects has been used as the basis to evaluate the probable incremental 
economic impacts of this designation of critical habitat.
    The final critical habitat designation for the western fanshell 
includes six units, all of which are occupied by the species. Ownership 
of riparian lands adjacent to the units includes 224.2 river mi (361 
km; 86 percent) in private ownership and 37.2 river mi (59.7 km; 14 
percent) in public (Federal or State government) ownership. The final 
critical habitat designation for the ``Ouachita'' fanshell includes 
three units, all of which are occupied by the species. Ownership of 
riparian lands adjacent to the units includes 227.2 river mi (365.7 km; 
99.8 percent) in private ownership and 0.5 river mi (0.8 km; 0.2 
percent) in public (State government) ownership.
    Total incremental costs of critical habitat designation for the 
western fanshell are not expected to exceed $48,000 (2021 dollars) per 
year (Industrial Economics, Inc. 2021, p. 18). With the exclusion of 
proposed Units WF 3, 4, and 9 and the Kansas portion of proposed Unit 
WF 8, we anticipate these costs will be even lower. Total incremental 
costs of critical habitat designation for the ``Ouachita'' fanshell are 
not expected to exceed $30,000 (2021 dollars) per year (Industrial 
Economics, Inc. 2021, p. 18). With the exclusion of proposed Unit OF 2 
and a portion of proposed Unit OF 4, we anticipate these costs will 
also be lower. The costs are reflective of: (1) All units are 
considered occupied, (2) project modifications requested to avoid 
adverse modification are likely to be the same as those recommended to 
avoid jeopardy in occupied habitat for these species, and (3) the 
designations receive baseline protection from the presence of critical 
habitat for co-occurring listed mussel species with similar habitat 
needs in 54 percent of the western fanshell's designated critical 
habitat and in 43 percent of the ``Ouachita'' fanshell's designated 
critical habitat. Because consultation will be required as a result of 
the listing of the western fanshell and ``Ouachita'' fanshell and is 
already required in some of these areas as a result of the presence of 
other listed species and critical habitats, the economic costs of the 
critical habitat designation will likely be primarily limited to 
additional administrative efforts to consider adverse modification for 
these two species in section 7 consultations (Industrial Economics, 
Inc. 2021, p. 12).
    Based on the consultation history regarding historical projects and 
activities overlapping the critical habitat area for the western 
fanshell, the number of future consultations, including technical 
assistance efforts, is likely to be no more than 23 per year across all 
six units. Based on the consultation history regarding historical 
projects and activities overlapping the critical habitat area for the 
``Ouachita'' fanshell, the number of future consultations, including 
technical assistance efforts, is likely to be no more than 15 per year 
across all three units. Overall, transportation and utilities 
activities are expected to result in the largest portion of 
consultations for both the western and ``Ouachita'' fanshells and, 
therefore, incur the highest costs. The geographic distribution of 
future section 7 consultations and associated costs are likely to be 
most heavily concentrated in western fanshell Unit 2 and ``Ouachita'' 
fanshell Unit 4. However, even assuming consultation activity increases 
substantially, incremental administrative costs are still likely to 
remain well under $100 million per year (Industrial Economics, Inc. 
2021, p. 18).
    We solicited data and comments from the public regarding the 
economic analysis, as well as all aspects of the March 3, 2022, 
proposed rule (87 FR 12338). We did not receive any additional 
information on economic impacts during the public comment period to 
determine whether any specific areas should be excluded from the final 
critical habitat designation under authority of the Act's section 
4(b)(2) and our implementing regulations at 50 CFR 424.19.
    As discussed above, we considered the economic impacts of the 
critical habitat designation, and the Secretary is not exercising her 
discretion to exclude any areas from this designation of critical 
habitat for the western fanshell and ``Ouachita'' fanshell based on 
economic impacts.
    A copy of the IEM and screening analysis with supporting documents 
may be obtained by contacting the Missouri Ecological Services Field 
Office (see FOR FURTHER INFORMATION CONTACT) or by downloading from the 
internet at https://www.regulations.gov.
Exclusions Based on Impacts on National Security and Homeland Security
    In preparing this rule, we determined that there are no lands 
within the designated critical habitat for western fanshell or 
``Ouachita'' fanshell that are

[[Page 41750]]

owned or managed by the DoD or Department of Homeland Security; 
therefore, we anticipate no impact on national security or homeland 
security. We did not receive any additional information during the 
public comment period for the proposed designation regarding impacts of 
the designation on national security or homeland security that would 
support excluding any specific areas from the final critical habitat 
designation under authority of section 4(b)(2) of the Act and our 
implementing regulations at 50 CFR 424.19, as well as the 2016 Policy.
Exclusions Based on Other Relevant Impacts
    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts on national 
security as discussed above. To identify other relevant impacts that 
may affect the exclusion analysis, we consider a number of factors, 
including whether there are permitted conservation plans covering the 
species in the area such as HCPs, SHAs, or CCAAs, or whether there are 
non-permitted conservation agreements and partnerships that would be 
encouraged by designation of, or exclusion from, critical habitat. In 
addition, we look at whether Tribal conservation plans or partnerships, 
Tribal resources, or government-to-government relationships of the 
United States with Tribal entities may be affected by the designation. 
We also consider any State, local, social, or other impacts that might 
occur because of the designation.
    When identifying the benefits of inclusion for an area, we consider 
the additional regulatory benefits that area would receive due to the 
protection from destruction or adverse modification as a result of 
actions with a Federal nexus, the educational benefits of mapping 
essential habitat for recovery of the listed species, and any benefits 
that may result from a designation due to State or Federal laws that 
may apply to critical habitat.
    In the case of western fanshell and ``Ouachita'' fanshell, the 
benefits of critical habitat include public awareness of the presence 
of the species and the importance of habitat protection, and, where a 
Federal nexus exists, increased habitat protection for western fanshell 
and ``Ouachita'' fanshell due to protection from destruction or adverse 
modification of critical habitat.
    When identifying the benefits of exclusion, we consider, among 
other things, whether exclusion of a specific area is likely to result 
in conservation, or in the continuation, strengthening, or 
encouragement of partnerships. Additionally, continued implementation 
of an ongoing management plan that provides equal to or more 
conservation than a critical habitat designation would reduce the 
benefits of including that specific area in the critical habitat 
designation.
    We evaluate the existence of a conservation plan when considering 
the benefits of inclusion. We consider a variety of factors, including, 
but not limited to, whether the plan is finalized; how it provides for 
the conservation of the essential physical or biological features; 
whether there is a reasonable expectation that the conservation 
management strategies and actions contained in a management plan will 
be implemented into the future; whether the conservation strategies in 
the plan are likely to be effective; and whether the plan contains a 
monitoring program or adaptive management to ensure that the 
conservation measures are effective and can be adapted in the future in 
response to new information.
    After identifying the benefits of inclusion and the benefits of 
exclusion, we carefully weigh the two sides to evaluate whether the 
benefits of exclusion outweigh those of inclusion. If our analysis 
indicates that the benefits of exclusion outweigh the benefits of 
inclusion, we then determine whether exclusion would result in 
extinction of the species. If exclusion of an area from critical 
habitat will result in extinction, we will not exclude it from the 
designation.
    Based on the information provided by entities seeking exclusion, as 
well as any additional public comments we received, and the best 
scientific data available, we evaluated whether certain lands in the 
proposed critical habitat Units WF 3, WF 4, WF 8, WF 9, OF 2, and OF 4 
are appropriate for exclusion from this final designation under section 
4(b)(2) of the Act. If our analysis indicates that the benefits of 
excluding lands from the final designation outweigh the benefits of 
designating those lands as critical habitat, then the Secretary may 
exercise her discretion to exclude the lands from the final 
designation. In the paragraphs below, we provide a detailed balancing 
analysis of the areas being excluded under section 4(b)(2) of the Act.
Private or Other Non-Federal Conservation Plans Related to Permits 
Under Section 10 of the Act
    HCPs for incidental take permits under section 10(a)(1)(B) of the 
Act provide for partnerships with non-Federal entities to minimize and 
mitigate impacts to listed species and their habitat. In some cases, 
HCP permittees agree to do more for the conservation of the species and 
their habitats on private lands than designation of critical habitat 
would provide alone. We place great value on the partnerships that are 
developed during the preparation and implementation of HCPs.
    CCAAs and SHAs are voluntary agreements designed to conserve 
candidate and listed species, respectively, on non-Federal lands. In 
exchange for actions that contribute to the conservation of species on 
non-Federal lands, participating property owners are covered by an 
``enhancement of survival'' permit under section 10(a)(1)(A) of the 
Act, which authorizes incidental take of the covered species that may 
result from implementation of conservation actions, specific land uses, 
and, in the case of SHAs, the option to return to a baseline condition 
under the agreements. We also provide enrollees assurances that we will 
not impose further land-, water-, or resource-use restrictions, or 
require additional commitments of land, water, or finances, beyond 
those agreed to in the agreements.
    When we undertake a discretionary section 4(b)(2) exclusion 
analysis, we will always consider areas covered by an approved CCAA/
SHA/HCP, and we anticipate consistently excluding such areas if 
incidental take caused by the activities in those areas is covered by 
the permit under section 10 of the Act and the CCAA/SHA/HCP meets all 
of the following three factors (see the 2016 Policy for additional 
details):
    a. The permittee is properly implementing the CCAA/SHA/HCP and is 
expected to continue to do so for the term of the agreement. A CCAA/
SHA/HCP is properly implemented if the permittee is, and has been, 
fully implementing the commitments and provisions in the CCAA/SHA/HCP, 
implementing agreement, and permit.
    b. The species for which critical habitat is being designated is a 
covered species in the CCAA/SHA/HCP, or very similar in its habitat 
requirements to a covered species. The recognition that we extend to 
such an agreement depends on the degree to which the conservation 
measures undertaken in the CCAA/SHA/HCP would also protect the habitat 
features of the similar species.
    c. The CCAA/SHA/HCP specifically addresses the habitat of the 
species for which critical habitat is being designated and meets the 
conservation needs of the species in the planning area.

[[Page 41751]]

The Kansas Aquatic Species Conservation Agreement: A Programmatic Safe 
Harbor Agreement and Candidate Conservation Agreement With Assurances 
for Fourteen Aquatic Species in Kansas (``Kansas Agreement'')
    In 2021, the Secretary of the KDWP signed the Kansas Agreement, and 
on December 13, 2022, the Service approved an amendment to this 
agreement, submitted by the State of Kansas, to include western 
fanshell as a covered species. The Kansas Agreement was part of an 
application for an enhancement-of-survival permit under section 
10(a)(1)(A) of the Act. The Kansas Agreement facilitates the 
introduction, reintroduction, augmentation, and translocation, and 
conserves the habitat, of imperiled native aquatic species in the State 
of Kansas. The Kansas Agreement, a programmatic SHA and CCAA, is 
between the KDWP and the Service (collectively, ``the Parties'').
    The Kansas Agreement covers all eligible, non-Federal lands in the 
State of Kansas for all eligible non-Federal landowners who wish to 
participate in the Kansas Agreement (``cooperators''). Non-Federal 
lands are those lands owned by non-Federal landowners which include, 
but are not limited to, State, Tribal, regional, or local governments; 
private or nonprofit organizations; or private citizens. By entering 
into this agreement, the Parties are using the Service's SHA and CCAA 
programs to further the conservation of the Nation's fish and wildlife. 
Both components of the Kansas Agreement and their associated permits 
target non-Federal lands in Kansas, whose owners or land managers are 
willing to engage in habitat management actions to benefit the species 
covered by the agreement (the ``covered species'').
    The duration of the Kansas Agreement is 50 years from its effective 
date. Each participating landowner, or cooperator, will enroll in the 
SHA, CCAA, or both through a landowner management agreement 
(``landowner agreement''). Once the landowner agreement is signed, KDWP 
will issue the cooperator a certificate of inclusion (COI). The 
duration of the landowner agreements entered into under the Kansas 
Agreement and the associated COI will be for the remaining duration of 
the permit unless another time period is agreed upon by the Parties and 
the cooperator.
    The conservation goals of the Kansas Agreement are to increase the 
resiliency, redundancy, and representation of the covered species' 
populations through reintroductions and to protect, enhance, and expand 
habitat availability (stream bed and banks). Under the Kansas 
Agreement, cooperators will maintain habitat available to the covered 
species and will assist with habitat conservation for the remainder of 
the term of the Kansas Agreement. Cooperators will facilitate the 
ability to reintroduce and augment populations and manage enrolled 
lands, as agreed to in their landowner agreement, in a manner that 
maintains existing habitat and improves and restores habitat for the 
covered species.
    Expected outcomes of implementing the Kansas Agreement include the 
protection, enhancement, and restoration of instream habitat; improved 
water quality; reduced erosion and sedimentation; improved riparian 
habitat; and improved land use practices on enrolled lands during the 
term of the Kansas Agreement. The Kansas Agreement covers activities 
that will maintain existing or baseline riparian habitat, ensure the 
connectivity of covered species, and adhere to best management 
practices to protect water quantity and quality. Cooperators are 
encouraged to include habitat management actions on enrolled lands that 
will enhance the habitat beyond the documented baseline or existing 
conditions. These activities could include establishment and 
enhancement of stream buffers; installation and maintenance of erosion 
and pollution control measures; cessation, reduction, or modification 
of land use practices, such as pesticide application, animal or vehicle 
activity in streamside areas, or ground disturbance; capture and 
treatment of stormwater or other runoff to improve water quality, and 
fish passage improvement projects. The Kansas Agreement includes the 
plains minnow, Topeka shiner, and Neosho madtom within the range of 
western fanshell and although these are not host fish for western 
fanshell, improvements to their habitat and populations would also 
benefit western fanshell host fish. Implementation of these activities 
would maintain and/or improve the physical or biological features of 
adequate flow, suitable substrate and connected instream habitat, water 
and sediment quality, and the presence and abundance of host fish. The 
reintroduction activities included in the Kansas Agreement will 
increase the probability that covered species will expand their range, 
survive, and recruit new cohorts in reintroduced areas. Under the 
Kansas Agreement, the criteria for eligible landowners with land 
neighboring western fanshell habitat is: ``Mainstem of waterbody where 
reintroduction occurs extending onto adjoining parcels, plus direct 
tributaries containing suitable habitat. Eligible property must also 
support suitable habitat for mainstem and direct tributaries (i.e., 
perennial flows and the presence of host fish species).'' The Kansas 
Agreement in its entirety can be found at: https://ecos.fws.gov/ecp/report/conservation-plan?plan_id=4829.
The Amended Programmatic Safe Harbor Agreement and Programmatic 
Candidate Conservation Agreement With Assurances for the Speckled 
Pocketbook, Yellowcheek Darter, Rabbitsfoot, and Nineteen Other Aquatic 
Species of Greatest Conservation Need in the Upper Little Red River 
Watershed, Arkansas (the ``Upper Little Red River Agreement'')
    In 2015, the Arkansas Game and Fish Commission (AGFC) and three 
other parties signed the Upper Little Red River Agreement, which 
includes western fanshell as a covered species. The Upper Little Red 
River Agreement was part of an application for an enhancement-of-
survival permit under section 10(a)(1)(A) of the Act. The agreement 
facilitates the conservation of habitat for 22 imperiled aquatic 
species in the upper Little Red River watershed in the State of 
Arkansas. The Upper Little Red River Agreement, a programmatic SHA and 
a CCAA, is between the AGFC, the Service, The Nature Conservancy, and 
Natural Resources Conservation Service (NRCS) (collectively, ``the 
Parties'').
    The Upper Little Red River Agreement covers all eligible, non-
Federal lands in the upper Little Red River watershed for all eligible 
non-Federal landowners (``cooperators'') who wish to participate in 
this agreement. Non-Federal lands are those lands owned by non-Federal 
landowners which include, but are not limited to, State, Tribal, 
regional, or local governments; private or nonprofit organizations; or 
private citizens. By entering into the Upper Little Red River 
Agreement, the Parties are using the Service's SHA and CCAA programs to 
further the conservation of the Nation's fish and wildlife. Both 
components of this agreement and their associated permits target non-
Federal lands in the upper Little Red River watershed in Arkansas, 
whose owners or land managers are willing to engage in habitat 
management actions to benefit the species covered by the agreement (the 
``covered species'').
    The duration of the Upper Little Red River Agreement is 29 years 
from its effective date, and the permit for the

[[Page 41752]]

Upper Little Red River Agreement expires on January 1, 2044. Each 
participating landowner, or cooperator, will enroll in the SHA, CCAA, 
or both through a property owner management agreement (POMA). Once the 
POMA is signed, the enrolling Party will issue the cooperator a 
certificate of inclusion (COI). The duration of the POMAs entered into 
under the Upper Little Red River Agreement and the associated COI will 
be for the remaining duration of the permit unless another time period 
is agreed upon by the Parties and cooperator.
    The conservation goals of the Upper Little Red River Agreement are 
to protect, enhance, and expand habitat availability (stream bed and 
banks); reduce sediment and pollutant runoff, thereby enhancing water 
quality and instream habitat (water and stream bed); and allow for 
subsequent natural population expansion or, if necessary, 
reintroduction of the covered species in the upper Little Red River 
watershed. Under the Upper Little Red River Agreement, cooperators will 
maintain habitat available to the covered species and will assist with 
habitat conservation for the remainder of the term of the Upper Little 
Red River Agreement. Cooperators will manage their enrolled lands in a 
manner that maintains existing habitat and improves and restores 
habitat for the covered species.
    Expected outcomes of implementing the Upper Little Red River 
Agreement include the protection, enhancement, and restoration of 
instream habitat; improved water quality; reduced erosion and 
sedimentation; improved riparian habitat; and improved land use 
practices on enrolled lands during the term of this agreement. 
Implementation of these activities would maintain and/or improve the 
physical or biological features of suitable substrate and connected 
instream habitat and water and sediment quality. The conservation 
activities included in the Upper Little Red River Agreement will 
increase the probability that covered species will expand their range, 
survive, and recruit new cohorts. A copy of the Upper Little Red River 
Agreement may be obtained by contacting the Arkansas Ecological 
Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Programmatic Safe Harbor Agreement and Candidate Conservation Agreement 
With Assurances for the Arkansas Fatmucket, Pink Mucket, Spectaclecase, 
Rabbitsfoot, Harperella, and Twenty Other Aquatic Species of Greatest 
Conservation Need in the Upper Saline, Caddo, and Ouachita River 
(Headwaters) Watersheds, Arkansas (the ``Headwaters Agreement'')
    In 2016, the AGFC and three other parties signed the Headwaters 
Agreement, which includes the ``Ouachita'' fanshell, which at the time 
was known as the western fanshell, as a covered species. The Headwaters 
Agreement was part of an application for an enhancement-of-survival 
permit under section 10(a)(1)(A) of the Act. The Headwaters Agreement 
facilitates the conservation of habitat of 25 imperiled aquatic species 
in the upper Saline, Caddo, and Ouachita River watersheds that occur in 
Saline, Grant, Garland, Hot Spring, Clark, Pike, Montgomery, and Polk 
Counties in the State of Arkansas. The Headwaters Agreement, a 
programmatic SHA and a CCAA, is between the AGFC, the Service, The 
Nature Conservancy, and Natural Resources Conservation Service (NRCS) 
(collectively, ``the Parties'').
    The Headwaters Agreement is structured identically to the 
aforementioned Upper Little Red River Agreement. The duration of the 
Headwaters Agreement is 35 years from its effective date, and the 
permit for the Headwaters Agreement expires on September 12, 2051. Each 
participating landowner, or cooperator, will enroll in the SHA, CCAA, 
or both, through a property owner management agreement (POMA). Once the 
POMA is signed, the enrolling Party will issue the cooperator a 
certificate of inclusion (COI). The duration of the POMAs entered into 
under the Headwaters Agreement and the associated COI will be for the 
remaining duration of the permit unless another time period is agreed 
upon by the Parties and cooperator.
    Expected outcomes of implementing the Headwaters Agreement include 
the protection, enhancement, and restoration of instream habitat; 
improved water quality; reduced erosion and sedimentation; improved 
riparian habitat; and improved land use practices on enrolled lands 
during the term of this agreement. Implementation of these activities 
would maintain and/or improve the physical or biological features of 
suitable substrate and connected instream habitat and water and 
sediment quality. The conservation activities included in the 
Headwaters Agreement will increase the probability that covered species 
will expand their range, survive, and recruit new cohorts. A copy of 
the Headwaters Agreement may be obtained by contacting the Arkansas 
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Benefits of Inclusion
    The principal benefit of including an area in critical habitat 
designation is the requirement of Federal agencies to ensure that 
actions that they fund, authorize, or carry out are not likely to 
result in the destruction or adverse modification of any designated 
critical habitat, which is the regulatory standard of section 7(a)(2) 
of the Act under which consultation is completed. In areas where a 
listed species occurs, Federal agencies must consult with the Service 
on actions that may affect a listed species and refrain from actions 
that are likely to jeopardize the continued existence of such 
species.The analysis of effects to critical habitat is a separate and 
different analysis from that of the effects to the species.Therefore, 
the difference in outcomes of these two analyses represents the 
regulatory benefit of critical habitat.Because all of the proposed 
critical habitat units for western fanshell and ``Ouachita'' fanshell 
are occupied by the species, there would be consultations for all areas 
based on the species' presence in those areas. As discussed above under 
Exclusions Based on Economic Impacts, we found limited distinction 
between baseline conservation efforts and incremental impacts of the 
designation of critical habitat for this species. Therefore, critical 
habitat designation may provide a limited regulatory benefit for the 
western fanshell and ``Ouachita'' fanshell on lands covered under the 
three agreements described above when there is a Federal nexus present 
for a project that might adversely modify critical habitat.
    Another possible benefit of including lands in critical habitat is 
public education regarding the special management considerations 
required and potential conservation value of an area that may help 
focus conservation efforts on areas of high conservation value for 
certain species.We consider any information about the western fanshell 
and ``Ouachita'' fanshell and their habitats that reaches a wide 
audience, including parties engaged in conservation activities, to be 
valuable. Designation of critical habitat would provide educational 
benefits by informing Federal agencies and the public about the 
presence of listed species for all units.

[[Page 41753]]

    In summary, we find that the benefits of inclusion of approximately 
64.4 river mi (103.6 km) of waterways in proposed Units WF 3, WF 8, and 
WF 9 in the State of Kansas and approximately 100.9 river mi (162.4 km) 
of waterways in proposed Unit WF 4 and proposed Units OF 2 and OF 4 in 
the State of Arkansas are: (1) A regulatory benefit when there is a 
Federal nexus present for a project that might adversely modify 
critical habitat; and (2) educational benefits for the western 
fanshell, ``Ouachita'' fanshell, and their habitats.
Benefits of Exclusion
    The benefits of excluding approximately 64.4 river mi (103.6 km) of 
Kansas waterways and approximately 100.9 river mi (162.4 km) of 
Arkansas waterways under the three SHA and CCAA agreements from the 
designation of critical habitat for the western fanshell and 
``Ouachita'' fanshell are substantial and include: (1) Continuance and 
strengthening of our effective working relationship with private 
landowners to promote voluntary, proactive conservation of the western 
fanshell, ``Ouachita'' fanshell, and their habitats; (2) allowance for 
continued meaningful collaboration and cooperation in working toward 
species recovery, including conservation benefits that might not 
otherwise occur; (3) inclusion of a monitoring program to ensure the 
conservation measures are effective; and (4) encouragement to develop 
additional conservation easements and other conservation and management 
plans in the future for other federally listed and sensitive species.
    Some landowners may perceive critical habitat as an unfair and 
unnecessary regulatory burden. According to some, the designation of 
critical habitat on (or adjacent to) private lands may reduce the 
likelihood that landowners will support and carry out conservation 
actions (Main et al. 1999, pp. 1,263-1,265; Bean 2002, p. 412). The 
magnitude of this negative outcome is greatly amplified in situations 
where active management measures (such as reintroduction, fire 
management, and control of invasive species) are necessary for species 
conservation (Bean 2002, pp. 412-414). We find that the exclusion of 
these specific areas of non-federally owned lands from the critical 
habitat designation for western fanshell and ``Ouachita'' fanshell can 
contribute to species recovery and provide a superior level of 
conservation than critical habitat can provide alone. We find that, 
where consistent with the discretion provided by the Act, it is 
necessary to implement policies that provide positive incentives to 
private landowners to voluntarily conserve natural resources and that 
remove or reduce disincentives to conservation (Wilcove et al. 1996, 
pp. 1-15; Bean 2002, entire).
    Additionally, partnerships with non-Federal landowners are vital to 
the conservation of listed species, especially on non-Federal lands; 
therefore, the Service is committed to supporting and encouraging such 
partnerships through the recognition of positive conservation 
contributions. In the case considered here, excluding these areas from 
critical habitat will help foster the partnerships the landowners and 
land managers in question have developed with Federal and State 
agencies and local conservation organizations, will encourage the 
continued implementation of voluntary conservation actions for the 
benefit of the western fanshell and ``Ouachita'' fanshell and their 
habitats on these lands, and may also serve as a model and aid in 
fostering future cooperative relationships with other parties here and 
in other locations for the benefit of other endangered or threatened 
species. Therefore, we consider the positive effect of excluding from 
critical habitat areas managed by active conservation partners to be a 
significant benefit of exclusion.
Benefits of Exclusion Outweigh the Benefits of Inclusion
    We evaluated the exclusion of approximately 165.3 river mi (266 km) 
of waterways adjacent to private land within the areas covered by the 
Kansas Agreement, Upper Little Red River Agreement, and Headwaters 
Agreement from our designation of critical habitat, and we determined 
the benefits of excluding these lands outweigh the benefits of 
including them as critical habitat for the western fanshell and 
``Ouachita'' fanshell.
    We conclude that the additional regulatory and educational benefits 
of including these lands as critical habitat are relatively small 
because of the limited distinction between actions to avoid jeopardy 
and adverse modification. These benefits are further reduced by the 
existence of these three agreements, which include habitat conservation 
that addresses the special management considerations.
    Furthermore, the potential educational and informational benefits 
of critical habitat designation on areas containing the physical and 
biological features essential to the conservation of the western 
fanshell and ``Ouachita'' fanshell would be minimal because the 
landowners and land managers under consideration have demonstrated 
their knowledge of the species and its habitat needs in the process of 
developing their partnerships with the Service.
    In contrast, the benefits derived from excluding the subject areas 
and enhancing our partnership with these landowners and land managers 
is significant. Because voluntary conservation efforts for the benefit 
of listed species on non-Federal lands are so valuable, the Service 
considers the maintenance and encouragement of conservation 
partnerships to be a significant benefit of exclusion. The development 
and maintenance of effective working partnerships with non-Federal 
landowners for the conservation of listed species is particularly 
important in areas such as Arkansas and Kansas, States with relatively 
little Federal landownership but many species of conservation concern. 
Excluding these areas from critical habitat will help foster the 
partnerships the landowners and land managers in question have 
developed with Federal and State agencies and local conservation 
organizations and will encourage the continued implementation of 
voluntary conservation actions for the benefit of the western fanshell 
and ``Ouachita'' fanshell and their habitats on these lands. The 
current active conservation efforts on some of these areas contribute 
to our knowledge of the species through monitoring and scientific 
research. In addition, these partnerships not only provide a benefit 
for the conservation of these species but may also serve as a model and 
aid in fostering future cooperative relationships with other parties in 
these areas of Arkansas and Kansas and in other locations for the 
benefit of other endangered or threatened species.
    We find that excluding areas from critical habitat that are 
receiving both long-term conservation and management for the purpose of 
protecting the habitat that supports the western fanshell and 
``Ouachita'' fanshell will preserve our partnership with the private 
landowners in the States of Arkansas and Kansas and will encourage 
future collaboration towards conservation and recovery of listed 
species. The partnership benefits are significant and outweigh the 
small potential regulatory, educational, and ancillary benefits of 
including the land in the final critical habitat designation for the 
western fanshell and ``Ouachita'' fanshell. Therefore, the agreements 
provide greater protection of habitat for the western fanshell and 
``Ouachita'' fanshell than could be gained through

[[Page 41754]]

the project-by-project analysis resulting from a critical habitat 
designation.
Exclusion Will Not Result in Extinction of the Species
    We determined that the exclusion of approximately 165.3 river mi 
(266 km) of waterways within the boundaries of the States of Arkansas 
and Kansas covered by the Kansas Agreement, Upper Little Red River 
Agreement, and Headwaters Agreement will not result in extinction of 
the western fanshell or ``Ouachita'' fanshell. Protections afforded to 
the western fanshell and ``Ouachita'' fanshell and their habitats by 
these three agreements provide assurances that these species will not 
go extinct as a result of excluding these lands from the critical 
habitat designation.
    An important consideration as we evaluate these exclusions and 
their potential effect on the species in question is that critical 
habitat does not carry with it a regulatory requirement to restore or 
actively manage habitat for the benefit of listed species; the 
regulatory effect of critical habitat is only the avoidance of 
destruction or adverse modification of critical habitat should an 
action with a Federal nexus occur. It is, therefore, advantageous for 
the conservation of these species to support the proactive efforts of 
non-Federal landowners who are contributing to the enhancement of 
essential habitat features for listed species through exclusion. The 
jeopardy standard of section 7 of the Act will also provide protection 
in these occupied areas when there is a Federal nexus.
Summary of Exclusions
    As discussed above, based on the information provided by entities 
seeking exclusion, as well as any additional public comments received, 
we evaluated whether certain lands in the proposed critical habitat 
were appropriate for exclusion from this final designation pursuant to 
section 4(b)(2) of the Act. We are excluding the following areas from 
critical habitat designation for the ``Ouachita'' fanshell and western 
fanshell: Unit OF 2, the upper portion of Unit OF 4, Unit WF 3, Unit WF 
4, the Kansas portion of Unit WF 8, and Unit WF 9. Tables 4 and 5, 
below, provide approximate areas that meet the definition of critical 
habitat but which we are excluding under section 4(b)(2) of the Act 
from this final critical habitat designation.

                    Table 4--Areas Excluded by Critical Habitat Unit for the Western Fanshell
----------------------------------------------------------------------------------------------------------------
                                                         Proposed critical                       Final critical
             Proposed critical habitat unit               habitat  (river     Area excluded     habitat  (river
                                                              mi (km))       (river mi (km))        mi (km))
----------------------------------------------------------------------------------------------------------------
WF 3: Fall River.......................................        45.5 (73.2)        45.5 (73.2)                  0
WF 4: Middle Fork Little Red River.....................        34.1 (54.9)        34.1 (54.9)                  0
WF 8: Spring River.....................................          15 (24.1)         6.5 (10.5)         8.5 (13.7)
WF 9: Verdigris River..................................          12.4 (20)          12.4 (20)                  0
----------------------------------------------------------------------------------------------------------------


                 Table 5--Areas Excluded by Critical Habitat Unit for the ``Ouachita'' Fanshell
----------------------------------------------------------------------------------------------------------------
                                                         Proposed critical                       Final critical
             Proposed critical habitat unit               habitat  (river     Area excluded     habitat  (river
                                                              mi (km))       (river mi (km))        mi (km))
----------------------------------------------------------------------------------------------------------------
OF 2: Ouachita Headwaters..............................        32.7 (52.6)        32.7 (52.6)                  0
OF 4: Saline River.....................................      185.3 (298.2)        34.1 (54.9)      151.3 (243.5)
----------------------------------------------------------------------------------------------------------------

Required Determinations

Regulatory Planning and Review (Executive Orders 12866 and 13563)

    Executive Order 12866 provides that the Office of Information and 
Regulatory Affairs (OIRA) in the Office of Management and Budget will 
review all significant rules. OIRA has determined that this rule is not 
significant.
    Executive Order 14094 reaffirms the principles of E.O. 12866 and 
E.O 13563 and states that regulatory analysis should facilitate agency 
efforts to develop regulations that serve the public interest, advance 
statutory objectives, and are consistent with E.O. 12866, E.O. 13563, 
and the Presidential Memorandum of January 20, 2021 (Modernizing 
Regulatory Review). Regulatory analysis, as practicable and 
appropriate, shall recognize distributive impacts and equity, to the 
extent permitted by law. E.O. 13563 emphasizes further that regulations 
must be based on the best available science and that the rulemaking 
process must allow for public participation and an open exchange of 
ideas. We have developed this rule in a manner consistent with these 
requirements.

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

    Under the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et seq.), 
as amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (SBREFA; 5 U.S.C. 801 et seq.), whenever an agency is required to 
publish a notice of rulemaking for any proposed or final rule, it must 
prepare and make available for public comment a regulatory flexibility 
analysis that describes the effects of the rule on small entities 
(i.e., small businesses, small organizations, and small government 
jurisdictions). However, no regulatory flexibility analysis is required 
if the head of the agency certifies the rule will not have a 
significant economic impact on a substantial number of small entities. 
The SBREFA amended the RFA to require Federal agencies to provide a 
certification statement of the factual basis for certifying that the 
rule will not have a significant economic impact on a substantial 
number of small entities.
    According to the Small Business Administration, small entities 
include small organizations such as independent nonprofit 
organizations; small governmental jurisdictions, including school 
boards and city and town governments that serve fewer than 50,000 
residents; and small businesses (13 CFR 121.201). Small businesses 
include manufacturing and mining concerns with fewer than 500 
employees, wholesale trade entities with fewer than 100 employees, 
retail and service businesses with less than $5 million in annual 
sales, general and heavy construction businesses with less than $27.5 
million in annual business, special trade contractors doing less than 
$11.5 million in annual business, and agricultural businesses with 
annual

[[Page 41755]]

sales less than $750,000. To determine if potential economic impacts to 
these small entities are significant, we considered the types of 
activities that might trigger regulatory impacts under this designation 
as well as types of project modifications that may result. In general, 
the term ``significant economic impact'' is meant to apply to a typical 
small business firm's business operations.
    Under the RFA, as amended, and as understood in light of recent 
court decisions, Federal agencies are required to evaluate the 
potential incremental impacts of rulemaking on those entities directly 
regulated by the rulemaking itself; in other words, the RFA does not 
require agencies to evaluate the potential impacts to indirectly 
regulated entities. The regulatory mechanism through which critical 
habitat protections are realized is section 7 of the Act, which 
requires Federal agencies, in consultation with the Service, to ensure 
that any action authorized, funded, or carried out by the agency is not 
likely to destroy or adversely modify critical habitat. Therefore, 
under section 7, only Federal action agencies are directly subject to 
the specific regulatory requirement (avoiding destruction and adverse 
modification) imposed by critical habitat designation. Consequently, it 
is our position that only Federal action agencies will be directly 
regulated by this designation. There is no requirement under the RFA to 
evaluate the potential impacts to entities not directly regulated. 
Moreover, Federal agencies are not small entities. Therefore, because 
no small entities will be directly regulated by this rulemaking, we 
certify that this critical habitat designation will not have a 
significant economic impact on a substantial number of small entities.
    During the development of this final rule, we reviewed and 
evaluated all information submitted during the comment period on the 
proposed rule (87 FR 12338; March 3, 2022) that may pertain to our 
consideration of the probable incremental economic impacts of this 
critical habitat designation. Based on this information, we affirm our 
certification that this critical habitat designation will not have a 
significant economic impact on a substantial number of small entities, 
and a regulatory flexibility analysis is not required.

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

    Executive Order 13211 (Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use) requires 
agencies to prepare Statements of Energy Effects when undertaking 
certain actions. Facilities that provide energy supply, distribution, 
or use occur within some units of the critical habitat designations 
(e.g., dams, pipelines) and may potentially be affected. We determined 
that consultations, technical assistance, and requests for species 
lists may be necessary in some instances. However, in our economic 
analysis, we did not find that these critical habitat designations will 
significantly affect energy supplies, distribution, or use. Therefore, 
this action is not a significant energy action, and no Statement of 
Energy Effects is required.

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

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make the following findings:
    (1) This final rule will not produce a Federal mandate. In general, 
a Federal mandate is a provision in legislation, statute, or regulation 
that would impose an enforceable duty upon State, local, or Tribal 
governments, or the private sector, and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or Tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and Tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or Tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; Aid to Families 
with Dependent Children work programs; Child Nutrition; Food Stamps; 
Social Services Block Grants; Vocational Rehabilitation State Grants; 
Foster Care, Adoption Assistance, and Independent Living; Family 
Support Welfare Services; and Child Support Enforcement. ``Federal 
private sector mandate'' includes a regulation that ``would impose an 
enforceable duty upon the private sector, except (i) a condition of 
Federal assistance or (ii) a duty arising from participation in a 
voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal Government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities that receive 
Federal funding, assistance, or permits, or that otherwise require 
approval or authorization from a Federal agency for an action, may be 
indirectly impacted by the designation of critical habitat, the legally 
binding duty to avoid destruction or adverse modification of critical 
habitat rests squarely on the Federal agency. Furthermore, to the 
extent that non-Federal entities are indirectly impacted because they 
receive Federal assistance or participate in a voluntary Federal aid 
program, the Unfunded Mandates Reform Act would not apply, nor would 
critical habitat shift the costs of the large entitlement programs 
listed above onto State governments.
    (2) We do not believe that this final rule will significantly or 
uniquely affect small governments because it will not produce a Federal 
mandate of $100 million or greater in any year, that is, it is not a 
``significant regulatory action'' under the Unfunded Mandates Reform 
Act. The designation of critical habitat imposes no obligations on 
State or local governments. Therefore, a Small Government Agency Plan 
is not required.

Takings--Executive Order 12630

    In accordance with E.O. 12630 (Government Actions and Interference 
with Constitutionally Protected Private Property Rights), we have 
analyzed the potential takings implications of designating critical 
habitat for the western fanshell and ``Ouachita'' fanshell in a takings 
implications assessment. The Act does not authorize the Service to 
regulate private actions on private lands or confiscate private 
property as a result of critical habitat designation. Designation of 
critical habitat does not affect land ownership, or establish any 
closures, or restrictions on use of or access to the designated areas. 
Furthermore, the designation of critical habitat does not affect 
landowner actions that do not require Federal funding or permits, nor 
does it preclude development of habitat conservation programs or 
issuance of incidental take permits to permit actions that do require 
Federal funding or permits to go forward. However, Federal agencies are 
prohibited from carrying

[[Page 41756]]

out, funding, or authorizing actions that would destroy or adversely 
modify critical habitat. A takings implications assessment has been 
completed and concludes that this designation of critical habitat for 
the western fanshell and ``Ouachita'' fanshell does not pose 
significant takings implications for lands within or affected by the 
designation.

Federalism--Executive Order 13132

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

Civil Justice Reform--Executive Order 12988

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

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

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

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

    Regulations adopted pursuant to section 4(a) of the Act are exempt 
from the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et 
seq.) and do not require an environmental analysis under NEPA. We 
published a notice outlining our reasons for this determination in the 
Federal Register on October 25, 1983 (48 FR 49244). This includes 
listing, delisting, and reclassification rules, as well as critical 
habitat designations and species-specific protective regulations 
promulgated concurrently with a decision to list or reclassify a 
species as threatened. The courts have upheld this position (e.g., 
Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 1995) (critical 
habitat); Center for Biological Diversity v. U.S. Fish and Wildlife 
Service, 2005 WL 2000928 (N.D. Cal. Aug. 19, 2005) (concurrent 4(d) 
rule)).
    However, when any of the areas that meet the definition of 
``critical habitat'' for the species are in States within the 
jurisdiction of the U.S. Court of Appeals for the Tenth Circuit, such 
as that of the western fanshell, we undertake a NEPA analysis for that 
critical habitat designation consistent with the Tenth Circuit's ruling 
in Catron County Board of Commissioners v. U.S. Fish and Wildlife 
Service, 75 F.3d 1429 (10th Cir. 1996). However, with the exclusion of 
all critical habitat within the State of Kansas, which is within the 
Tenth Circuit, we have not prepared an environmental analysis pursuant 
to NEPA.

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), Executive Order 13175 (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. We have identified no Tribal interests 
that will be affected by this rule.

References Cited

    A complete list of all references cited is available on the 
internet at https://www.regulations.gov and upon request from the 
Missouri Ecological Services Field Office for western fanshell and the 
Arkansas Ecological Services Field Office for ``Ouachita'' fanshell 
(see FOR FURTHER INFORMATION CONTACT).

Authors

    The primary authors of this final rule are the staff members of the 
Fish and Wildlife Service's Species Assessment Team and the Missouri 
and Arkansas Ecological Services Field Offices.

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

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

[[Page 41757]]

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 ``Fanshell, `Ouachita' '' and 
``Fanshell, western'' in alphabetical order under CLAMS to read as 
follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                          Listing citations and
           Common name              Scientific name      Where listed         Status         applicable rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
              Clams
 
                                                  * * * * * * *
Fanshell, ``Ouachita''..........  Cyprogenia cf.      Wherever found....  T              88 FR [Insert Federal
                                   aberti.                                                Register page where
                                                                                          the document begins],
                                                                                          June 27, 2023; 50 CFR
                                                                                          17.45(f); \4d\
                                                                                         50 CFR 17.95(f).\CH\
Fanshell, western...............  Cyprogenia aberti.  Wherever found....  T              88 FR [Insert Federal
                                                                                          Register page where
                                                                                          the document begins],
                                                                                          June 27, 2023; 50 CFR
                                                                                          17.45(f); \4d\
                                                                                         50 CFR 17.95(f).\CH\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------


0
3. Amend Sec.  17.45 by adding reserved paragraphs (c) through (e) and 
paragraph (f) to read as follows:


Sec.  17.45  Special rules--snails and clams.

* * * * *
    (c)-(e) [Reserved]
    (f) ``Ouachita'' fanshell (Cyprogenia cf. aberti) and western 
fanshell (Cyprogenia aberti)--(1) Prohibitions. The following 
prohibitions that apply to endangered wildlife also apply to the 
``Ouachita'' fanshell and western fanshell. Except as provided under 
paragraph (f)(2) of this section and Sec. Sec.  17.4 and 17.5, it is 
unlawful for any person subject to the jurisdiction of the United 
States to commit, to attempt to commit, to solicit another to commit, 
or cause to be committed, any of the following acts in regard to this 
species:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken specimens, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of commercial 
activity, as set forth at Sec.  17.21(e) for endangered wildlife.
    (v) Sale or offer for sale, as set forth at Sec.  17.21(f) for 
endangered wildlife.
    (2) Exceptions from prohibitions. In regard to this species, you 
may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take, as set forth at Sec.  17.31(b).
    (iv) Take incidental to an otherwise lawful activity caused by:
    (A) Channel and bank restoration projects for creation of natural, 
physically stable, ecologically functioning streams, taking into 
consideration connectivity with floodplain and groundwater aquifers. 
These projects can be accomplished using a variety of methods, but the 
desired outcome is a natural channel with low shear stress (force of 
water moving against the channel); bank heights that enable 
reconnection to the floodplain; connection of surface and groundwater 
systems, resulting in perennial flows in the channel; riffles and pools 
comprised of existing soil, rock, and wood instead of large imported 
materials; low compaction of soils within adjacent riparian areas; and 
inclusion of riparian wetlands. For bank stabilization projects that 
use bioengineering methods to replace preexisting, bare, eroding stream 
banks with vegetated, stable stream banks, thereby reducing bank 
erosion and instream sedimentation and improving habitat conditions for 
the species, stream banks may be stabilized using native species live 
stakes (live, vegetative cuttings inserted or tamped into the ground in 
a manner that allows the stake to take root and grow), native species 
live fascines (live branch cuttings, usually willows, bound together 
into long, cigar-shaped bundles), or native species brush layering 
(cuttings or branches of easily rooted tree species layered between 
successive lifts of soil fill). Bank restoration projects require 
planting appropriate native vegetation, including woody species 
appropriate for the region and habitat. These projects will not include 
the sole use of quarried rock (rip-rap) or the use of rock baskets or 
gabion structures. To qualify under this exception, restoration 
projects must include the following:
    (1) Surveys to determine presence of ``Ouachita'' fanshell and 
western fanshell prior to the commencement of restoration actions;
    (2) If either mussel is present, coordination with the Service's 
local Ecological Services field office for relocation of ``Ouachita'' 
fanshell and western fanshell mussels to suitable habitat outside of 
the project footprint prior to project implementation; and
    (3) If relocation of mussels occurs, monitoring of relocated 
mussels post-implementation of restoration activities.
    (B) Silviculture practices and forest management activities that 
use State-approved best management practices to protect water and 
sediment quality and stream and riparian habitat.
    (C) Transportation projects that avoid or do not include instream 
disturbance in waters occupied by the species.
    (v) Purposeful take that results from capture, handling, and 
release related to presence/absence surveys, studies to document 
habitat use, and population monitoring by individuals permitted to 
conduct these same activities for other species of mussels until 
January 25, 2024.
    (vi) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.

0
4. In Sec.  17.95, amend paragraph (f) by adding entries for 
```Ouachita' Fanshell (Cyprogenia cf. aberti)'' and ``Western Fanshell 
(Cyprogenia aberti)''

[[Page 41758]]

immediately following the entry for ``Appalachian Elktoe (Alasmidonta 
raveneliana)'' to read as follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and Snails.
* * * * *
``Ouachita'' Fanshell (Cyprogenia cf. aberti)

    (1) Critical habitat units are depicted for Ashley, Bradley, Clark, 
Cleveland, Dallas, Drew, Grant, Nevada, and Ouachita Counties, 
Arkansas, on the maps in this entry.
    (2) Within these areas, the physical or biological features 
essential to the conservation of ``Ouachita'' fanshell consist of the 
following components:
    (i) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species is found and to maintain stream connectivity, specifically 
providing for the exchange of nutrients and sediment for maintenance of 
the mussel's and fish hosts' habitat and food availability, maintenance 
of spawning habitat for native host fishes, and the ability for newly 
transformed juveniles to settle and become established in their 
habitats. Adequate flows ensure delivery of oxygen, enable 
reproduction, deliver food to filter-feeding mussels, and reduce 
contaminants and fine sediments from interstitial spaces.
    (ii) Suitable substrates and connected instream habitats, 
characterized by geomorphically stable stream channels and banks (that 
is, channels that maintain lateral dimensions, longitudinal profiles, 
and sinuosity patterns over time without an aggrading or degrading bed 
elevation) with habitats that support a diversity of freshwater mussel 
and native fish (such as stable riffle-run-pool habitats that provide 
flow refuges consisting of silt-free gravel and coarse sand 
substrates).
    (iii) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including, but not limited to, dissolved oxygen 
(generally above 3 parts per million (ppm)) and water temperature 
(generally below 80 degrees Fahrenheit ([deg]F) (27 degrees Celsius 
([deg]C)). Additionally, water and sediment should be low in ammonia 
(generally below 1.0 ppm total ammonia-nitrogen) and heavy metals, and 
lack excessive total suspended solids and other pollutants.
    (iv) The presence and abundance of fish hosts necessary for 
recruitment of the ``Ouachita'' fanshell, including logperch (Percina 
caprodes), slenderhead darter (Percina phoxocephala), or orangebelly 
darter (Etheostoma radiosum).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
July 27, 2023.
    (4) Data layers defining map units were created by overlaying 
Natural Heritage Element Occurrence data and U.S. Geological Survey 
hydrologic data for stream reaches using ESRI ArcGIS mapping software. 
Critical habitat unit upstream and downstream limits were delineated at 
the nearest road crossing or stream confluence of each occupied reach. 
Data layers defining map units were created with U.S. Geological Survey 
National Hydrography Dataset (NHD) Medium Flowline data. ArcGIS was 
also used to calculate river kilometers and river miles from the NHD 
dataset, and it was used to determine longitude and latitude 
coordinates in decimal degrees. The projection used in mapping and 
calculating distances and locations within the units was EPSG:4269-
NAD83 Geographic. Natural Heritage program and State mussel database 
species presence data from Arkansas were used to select specific river 
and stream segments for inclusion in the critical habitat layer. The 
maps in this entry, as modified by any accompanying regulatory text, 
establish the boundaries of the critical habitat designation. The 
coordinates or plot points or both on which each map is based are 
available to the public at the Service's internet site at https://www.fws.gov/species/ouachita-fanshell-cyprogenia-sp-cf-aberti, at 
https://www.regulations.gov at Docket No. FWS-R3-ES-2021-0061, and at 
the field office responsible for this designation. You may obtain field 
office location information by contacting one of the Service regional 
offices, the addresses of which are listed at 50 CFR 2.2.
    (5) Index map for ``Ouachita'' fanshell critical habitat units 
follows:

BILLING CODE 4333-15-P
Figure 1 to ``Ouachita'' Fanshell (Cyprogenia cf. aberti) paragraph (5)

[[Page 41759]]

[GRAPHIC] [TIFF OMITTED] TR27JN23.002

    (6) Unit OF 1: Little Missouri River; Clark, Nevada, and Ouachita 
Counties, Arkansas.
    (i) Unit OF 1 consists of 22.9 river miles (mi) (36.9 kilometers 
(km)) of Little Missouri River in Clark, Nevada, and Ouachita Counties, 
Arkansas, from the mouth of Garland Creek northeast of Prescott, Nevada 
County, downstream to the mouth of Horse Branch north of Red Hill, 
Ouachita County. Unit OF 1 includes the river channel up to the 
ordinary high water mark. Approximately 100 percent of the riparian 
lands that border the unit are in private ownership.
    (ii) Map of Unit OF 1 follows:

Figure 2 to ``Ouachita'' Fanshell (Cyprogenia cf. aberti) paragraph 
(6)(ii)


[[Page 41760]]


[GRAPHIC] [TIFF OMITTED] TR27JN23.003

    (7) Unit OF 2 has been excluded from this critical habitat 
designation.
    (8) Unit OF 3: Ouachita River; Clark, Dallas, and Ouachita 
Counties, Arkansas.
    (i) Unit OF 3 consists of 53.5 river mi (86.1 km) of Ouachita River 
in Clark, Dallas, and Ouachita Counties, Arkansas, from the mouth of 
L'Eau Frais Creek southeast of Arkadelphia, Clark County, downstream to 
the mouth of Ecore Fabre Bayou north of Camden, Ouachita County. Unit 
OF 3 includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership. There is a Wetlands Reserve Program easement 
within the unit.
    (ii) Map of Unit OF 3 follows:

Figure 3 to ``Ouachita'' Fanshell (Cyprogenia cf. aberti) paragraph 
(8)(ii)

[[Page 41761]]

[GRAPHIC] [TIFF OMITTED] TR27JN23.004

    (9) Unit OF 4: Saline River; Ashley, Bradley, Cleveland, Dallas, 
Drew, and Grant Counties, Arkansas.
    (i) Unit OF 4 consists of 151.3 river mi (243.5 km) of Saline River 
in Ashley, Bradley, Cleveland, Dallas, Drew, and Grant Counties, 
Arkansas, from U.S. Highway 270 east of Poyen, Grant County, downstream 
to the mouth of Mill Creek north of Stillions, Ashley County. Unit OF 4 
includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership, and less than 1 percent is in public 
ownership. The public ownership in this unit is State-owned land 
associated with Jenkins Ferry State Park.
    (ii) Map of Unit OF 4 follows:

Figure 4 to ``Ouachita'' Fanshell (Cyprogenia cf. aberti) paragraph 
(9)(ii)

[[Page 41762]]

[GRAPHIC] [TIFF OMITTED] TR27JN23.005

Western Fanshell (Cyprogenia aberti)

    (1) Critical habitat units are depicted for Fulton, Independence, 
Jackson, Lawrence, Randolph, and Sharp Counties, Arkansas, and Butler, 
Jasper, Madison, and Wayne Counties, Missouri, on the maps in this 
entry.
    (2) Within these areas, the physical or biological features 
essential to the conservation of western fanshell consist of the 
following components:
    (i) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species is found and to maintain stream connectivity, specifically 
providing for the exchange of nutrients and sediment for maintenance of 
the mussel's and fish hosts' habitat and food availability, maintenance 
of spawning habitat for native host fishes, and the ability for newly 
transformed juveniles to settle and become established in their 
habitats. Adequate flows ensure delivery of oxygen, enable 
reproduction, deliver food to filter-feeding mussels,

[[Page 41763]]

and reduce contaminants and fine sediments from interstitial spaces.
    (ii) Suitable substrates and connected instream habitats, 
characterized by geomorphically stable stream channels and banks (that 
is, channels that maintain lateral dimensions, longitudinal profiles, 
and sinuosity patterns over time without an aggrading or degrading bed 
elevation) with habitats that support a diversity of freshwater mussel 
and native fish (such as stable riffle-run-pool habitats that provide 
flow refuges consisting of silt-free gravel and coarse sand 
substrates).
    (iii) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including, but not limited to: dissolved oxygen 
(generally above 3 parts per million (ppm)) and water temperature 
(generally below 80 degrees Fahrenheit ([deg]F) (27 degrees Celsius 
([deg]C)). Additionally, water and sediment should be low in ammonia 
(generally below 1.0 ppm total ammonia-nitrogen) and heavy metals, and 
lack excessive total suspended solids and other pollutants.
    (iv) The presence and abundance of fish hosts necessary for 
recruitment of the western fanshell, including logperch (Percina 
caprodes), rainbow darter (Etheostoma caeruleum), slenderhead darter 
(Percina phoxocephala), fantail darter (Etheostoma flabellare), or 
orangebelly darter (Etheostoma radiosum).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
July 27, 2023.
    (4) Data layers defining map units were created by overlaying 
Natural Heritage Element Occurrence data and U.S. Geological Survey 
hydrologic data for stream reaches using ESRI ArcGIS mapping software. 
Critical habitat unit upstream and downstream limits were delineated at 
the nearest road crossing or stream confluence of each occupied reach. 
Data layers defining map units were created with U.S. Geological Survey 
National Hydrography Dataset (NHD) Medium Flowline data. ArcGIS was 
also used to calculate river kilometers and river miles from the NHD 
dataset, and it was used to determine longitude and latitude 
coordinates in decimal degrees. The projection used in mapping and 
calculating distances and locations within the units was EPSG:4269-
NAD83 Geographic. Natural Heritage program and State mussel database 
species presence data from Arkansas and Missouri were used to select 
specific river and stream segments for inclusion in the critical 
habitat layer. The maps in this entry, as modified by any accompanying 
regulatory text, establish the boundaries of the critical habitat 
designation. The coordinates or plot points or both on which each map 
is based are available to the public at the Service's internet site at 
https://www.fws.gov/species/western-fanshell-cyprogenia-aberti, at 
https://www.regulations.gov at Docket No. FWS-R3-ES-2021-0061, and at 
the field office responsible for this designation. You may obtain field 
office location information by contacting one of the Service regional 
offices, the addresses of which are listed at 50 CFR 2.2.
    (5) Index map for western fanshell critical habitat units follows:

Figure 1 to Western Fanshell (Cyprogenia aberti) paragraph (5)

[[Page 41764]]

[GRAPHIC] [TIFF OMITTED] TR27JN23.006

    (6) Unit WF 1: Upper Black River; Butler and Wayne Counties, 
Missouri.
    (i) Unit WF 1 consists of 64.7 river miles (mi) (104.1 kilometers 
(km)) of Black River in Butler and Wayne Counties, Missouri, from 
Clearwater Dam southwest of Piedmont, Wayne County, extending 
downstream to Butler County Road 658 crossing southeast of Poplar 
Bluff, Butler County. Unit WF 1 includes the river channel up to the 
ordinary high water mark. Riparian lands that border the unit include 
approximately 51 river mi (82.1 km; 79 percent) in private ownership 
and 13.7 river mi (22 km; 21 percent) in public (Federal or State) 
ownership. Approximately 2.7 miles of the public ownership in this unit 
are State lands associated with Missouri Department of Conservation's 
(MDC) Bradley A. Hammer Memorial Conservation Area, Dan River Access, 
Hilliard Access, and Stephen J. Sun Conservation Area. Eleven miles are 
Federal land associated with the U.S. Forest Service's (USFS) Mark 
Twain National Forest and U.S.

[[Page 41765]]

Army Corps of Engineers' Clearwater Recreation Area.
    (ii) Map of Unit WF 1 follows:

Figure 2 to Western Fanshell (Cyprogenia aberti) paragraph (6)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.007

    (7) Unit WF 2: Lower Black/Strawberry River; Independence, Jackson, 
Lawrence, and Sharp Counties, Arkansas.
    (i) Unit WF 2 consists of 111.3 river mi (179.1 km) of Black River 
and Strawberry River in Independence, Jackson, Lawrence, and Sharp 
Counties in Arkansas. Unit WF 2 includes the river channel up to the 
ordinary high water mark. Black River makes up 54.6 river mi (87.9 km) 
from the mouth of Spring River northeast of Black Rock, extending 
downstream to the mouth of

[[Page 41766]]

Strawberry River northeast of Dowdy, Independence County. Strawberry 
River makes up 56.7 river mi (91.2 km) from the mouth of Lave Creek 
north of Evening Shade, Sharp County, extending downstream to the 
confluence with Black River northeast of Dowdy, Independence County. 
Riparian lands that border the unit include approximately 100.4 river 
mi (161.6 km; 90 percent) in private ownership and 10.9 river mi (17.5 
km; 10 percent) in public (State) ownership. The public land ownership 
in this unit is associated with Arkansas Game and Fish Commission's 
Shirey Bay Rainey Brake Wildlife Management Area on Black River. The 
Nature Conservancy's Strawberry River Preserve and Ranch on Strawberry 
River is also in this unit.
    (ii) Map of Unit WF 2 follows:

Figure 3 to Western Fanshell (Cyprogenia aberti) paragraph (7)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.008


[[Page 41767]]


    (8) Units WF 3 and WF 4 have been excluded from this critical 
habitat designation.
    (9) Unit WF 5: St. Francis River; Madison and Wayne Counties, 
Missouri.
    (i) Unit WF 5 consists of 49.3 river mi (79.3 km) of St. Francis 
River in Madison and Wayne Counties, Missouri, extending from the mouth 
of Wachita Creek west of Fredericktown, Madison County, downstream to 
the mouth of Big Creek northwest of Silva, Wayne County. Unit WF 5 
includes the river channel up to the ordinary high water mark. Riparian 
lands that border the unit include approximately 36.7 river mi (59.1 
km; 74 percent) in private ownership and 12.6 river mi (20.2 km; 26 
percent) in public (Federal or State) ownership. Approximately 2.4 
river mi of the public ownership in this unit are State lands 
associated with MDC's Coldwater Conservation Area, Mill Stream Gardens, 
and Roselle Access. Ten miles are Federal land associated with the 
USFS's Mark Twain National Forest.
    (ii) Map of Unit WF 5 follows:

Figure 4 to Western Fanshell (Cyprogenia aberti) paragraph (9)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.009


[[Page 41768]]


    (10) Unit WF 6: South Fork Spring River; Fulton County, Arkansas.
    (i) Unit WF 6 consists of 13.4 river mi (21.6 km) of South Fork 
Spring River in Fulton County, Arkansas, from the mouth of Camp Creek 
east of Salem, Fulton County, extending downstream to the Arkansas 
Highway 289 crossing northwest of Cherokee Village, Fulton County. Unit 
WF 6 includes the river channel up to the ordinary high water mark. 
Approximately 100 percent of the riparian lands that border the unit 
are in private ownership.
    (ii) Map of Unit WF 6 follows:

Figure 5 to Western Fanshell (Cyprogenia aberti) paragraph (10)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.010


[[Page 41769]]


    (11) Unit WF 7: Spring River (AR); Lawrence and Randolph Counties, 
Arkansas.
    (i) Unit WF 7 consists of 14.2 river mi (22.9 km) of Spring River 
in Lawrence and Randolph Counties, Arkansas, from the mouth of Wells 
Creek at Ravenden, extending downstream to the mouth of Stennitt Creek 
southeast of Imboden, Lawrence County. Unit WF 7 includes the river 
channel up to the ordinary high water mark. Approximately 100 percent 
of the riparian lands that border the unit are in private ownership.
    (ii) Map of Unit WF 7 follows:

Figure 6 to Western Fanshell (Cyprogenia aberti) paragraph (11)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.011

    (12) Unit WF 8: Spring River (MO); Jasper County, Missouri.
    (i) Unit WF 8 consists of 8.5 river mi (13.7 km) of Spring River in 
Jasper County, Missouri, from the mouth of North Fork Spring River east 
of Asbury,

[[Page 41770]]

Jasper County, Missouri, extending downstream to the Kansas State line, 
then from where it reenters Missouri to the mouth of Center Creek west 
of Carl Junction, Jasper County, Missouri. Unit WF 8 includes the river 
channel up to the ordinary high water mark. Approximately 100 percent 
of the riparian lands that border the unit are in private ownership.
    (ii) Map of Unit WF 8 follows:

Figure 7 to Western Fanshell (Cyprogenia aberti) paragraph (12)(ii)
[GRAPHIC] [TIFF OMITTED] TR27JN23.012


[[Page 41771]]


    (13) Unit WF 9 has been excluded from this critical habitat 
designation.
* * * * *

Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-13461 Filed 6-26-23; 8:45 am]
BILLING CODE 4333-15-C