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Rule2026-08146

Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Rayed Bean, Sheepnose, Snuffbox, and Spectaclecase Mussels

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Published

April 27, 2026

Effective

May 27, 2026

Issuing agencies

Interior DepartmentFish and Wildlife Service

Abstract

We, the U.S. Fish and Wildlife Service (Service), are designating critical habitat for the rayed bean (Villosa fabalis), sheepnose (Plethobasus cyphyus), snuffbox (Epioblasma triquetra), and spectaclecase (Cumberlandia monodonta), all species of freshwater mussel, under the Endangered Species Act of 1973, as amended (Act). Specifically, we designate approximately 599 river miles (rmi) (964 river kilometers (rkm)) in 15 units as critical habitat for rayed bean; approximately 801 rmi (1,289 rkm) in 11 units as critical habitat for sheepnose; approximately 2,425 rmi (3,902 rkm) in 38 units as critical habitat for snuffbox; and approximately 1,140 rmi (1,835 rkm) in 12 units as critical habitat for spectaclecase. Portions of these designations overlap among the four species; in total, approximately 3,814 unique rmi (6,138 rkm) of critical habitat within 76 units across 17 States (Alabama, Arkansas, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Mississippi, Missouri, New York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin) fall within the boundaries of the critical habitat designations.

Full Text

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[Federal Register Volume 91, Number 80 (Monday, April 27, 2026)]
[Rules and Regulations]
[Pages 22590-22702]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-08146]

[[Page 22589]]

Vol. 91

Monday,

No. 80

April 27, 2026

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; Designation of Critical
Habitat for the Rayed Bean, Sheepnose, Snuffbox, and Spectaclecase
Mussels; Proposed Rule

Federal Register / Vol. 91 , No. 80 / Monday, April 27, 2026 / Rules
and Regulations

[[Page 22590]]

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R3-ES-2024-0144; FXES1111090FEDR-267-FF09E21000]
RIN 1018-BH73

Endangered and Threatened Wildlife and Plants; Designation of
Critical Habitat for the Rayed Bean, Sheepnose, Snuffbox, and
Spectaclecase Mussels

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are
designating critical habitat for the rayed bean (Villosa fabalis),
sheepnose (Plethobasus cyphyus), snuffbox (Epioblasma triquetra), and
spectaclecase (Cumberlandia monodonta), all species of freshwater
mussel, under the Endangered Species Act of 1973, as amended (Act).
Specifically, we designate approximately 599 river miles (rmi) (964
river kilometers (rkm)) in 15 units as critical habitat for rayed bean;
approximately 801 rmi (1,289 rkm) in 11 units as critical habitat for
sheepnose; approximately 2,425 rmi (3,902 rkm) in 38 units as critical
habitat for snuffbox; and approximately 1,140 rmi (1,835 rkm) in 12
units as critical habitat for spectaclecase. Portions of these
designations overlap among the four species; in total, approximately
3,814 unique rmi (6,138 rkm) of critical habitat within 76 units across
17 States (Alabama, Arkansas, Illinois, Indiana, Iowa, Kentucky,
Michigan, Minnesota, Mississippi, Missouri, New York, Ohio,
Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin) fall
within the boundaries of the critical habitat designations.

DATES: This rule is effective May 27, 2026.

ADDRESSES: This final rule is available on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. Comments and materials we received are available
for public inspection at <a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-
R3-ES-2024-0144.
Availability of supporting materials: Supporting materials we used
in preparing this rule, such as the species status assessment reports
and recovery plan, are available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> at
Docket No. FWS-R3-ES-2024-0144, or at the Service's website on each
individual species' page (rayed bean: <a href="https://www.fws.gov/species/rayed-bean-villosa-fabalis">https://www.fws.gov/species/rayed-bean-villosa-fabalis</a>; sheepnose: <a href="https://www.fws.gov/species/sheepnose-plethobasus-cyphyus">https://www.fws.gov/species/sheepnose-plethobasus-cyphyus</a>; snuffbox: <a href="https://www.fws.gov/species/snuffbox-epioblasma-triquetra">https://www.fws.gov/species/snuffbox-epioblasma-triquetra</a>; spectaclecase: <a href="https://www.fws.gov/species/spectaclecase-cumberlandia-monodonta">https://www.fws.gov/species/spectaclecase-cumberlandia-monodonta</a>). The coordinates or plot
points or both from which the critical habitat maps are generated are
included in the decision file for this critical habitat designation and
are available at <a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-R3-ES-
2024-0144.

FOR FURTHER INFORMATION CONTACT: Rayed bean and snuffbox: Erin Knoll,
Field Supervisor, U.S. Fish and Wildlife Service, Ohio Ecological
Services Field Office; telephone 614-416-8993; <a href="/cdn-cgi/l/email-protection#adc8dfc4c3f2c6c3c2c1c1edcbdade83cac2db">[email&#160;protected]</a>;
sheepnose: Kraig McPeek, Field Supervisor, U.S. Fish and Wildlife
Service, Illinois-Iowa Ecological Services Field Office; telephone 309-
757-5800; <a href="/cdn-cgi/l/email-protection#deb5acbfb7b981b3bdaebbbbb59eb8a9adf0b9b1a8">[email&#160;protected]</a>; spectaclecase: Rob Tawes, Field
Supervisor, U.S. Fish and Wildlife Service, Minnesota-Wisconsin
Ecological Services Field Office; telephone 612-240-6343;
<a href="/cdn-cgi/l/email-protection#8dffe2efe8fff9d2f9ecfae8fecdebfafea3eae2fb">[email&#160;protected]</a>. Individuals in the United States who are deaf,
deafblind, hard of hearing, or have a speech disability may dial 711
(TTY, TDD, or TeleBraille) to access telecommunications relay services.
Individuals outside the United States should use the relay services
offered within their country to make international calls to the point-
of-contact in the United States.

SUPPLEMENTARY INFORMATION:

Executive Summary

Why we need to publish a rule. Under the Act (16 U.S.C. 1531 et
seq.), when we determine that any species is an endangered or
threatened species, we are required to designate critical habitat to
the maximum extent prudent and determinable. We are finalizing a
designation of critical habitat for four species of freshwater mussels.
Designation of 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 will designate critical habitat
for the rayed bean, sheepnose, snuffbox, and spectaclecase mussels;
these four freshwater mussel species have been listed as endangered
species under the Act since 2012 (See 77 FR 8632, February 14, 2012,
and 77 FR 14914, March 13, 2012).
The basis for our action. Under section 4(a)(3) of the Act, if we
determine a species is an endangered or threatened species, the
Secretary of the Interior (Secretary) must designate critical habitat
to the maximum extent prudent and determinable. 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.

Previous Federal Actions

Please refer to the December 13, 2024, proposed critical habitat
rule (89 FR 101100) for a detailed description of previous Federal
actions concerning the rayed bean, sheepnose, snuffbox, and
spectaclecase mussels.

Peer Review

A species status assessment (SSA) team prepared an SSA report for
each of the four mussel species. The SSA team was composed of Service
biologists, in consultation with other species experts. The SSA reports
represent a compilation of the best scientific and commercial data
available concerning the status of the species, including the impacts
of past, present, and future factors (both negative and beneficial)
affecting the species.
In accordance with our joint policy on peer review published in the
Federal Register on July 1, 1994 (59 FR 34270), and our August 22,
2016, memorandum updating and clarifying the role of peer review in
listing and recovery actions under the Act (<a href="https://www.fws.gov/sites/default/files/documents/peer-review-policy-directors-memo-2016-08-22.pdf">https://www.fws.gov/sites/default/files/documents/peer-review-policy-directors-memo-2016-08-22.pdf</a>), we solicited independent scientific review of the information
contained in the SSA reports for the rayed bean (Service 2022a,
entire), sheepnose (Service 2022b, entire), snuffbox (Service 2022c,
entire), and spectaclecase (Service 2022d, entire). As discussed in the
proposed rule, we sent the SSA reports to 10 independent peer

[[Page 22591]]

reviewers and received 9 responses. The peer reviews can be found at
<a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-R3-ES-2024-0144. In
preparing the proposed rule, we incorporated the results of these
reviews, as appropriate, into the SSA report, which was the foundation
for the proposed rule and this final rule. A summary of the peer review
comments and our responses can be found in the December 13, 2024,
proposed rule (89 FR 101100).

Summary of Changes From the Proposed Rule

After considering the comments we received during the public
comment period for our December 13, 2024, proposed rule to designate
critical habitat for the rayed bean, sheepnose, snuffbox, and
spectaclecase mussels (89 FR 101100) and relevant information that
became available since the proposed rule published, we made changes to
this final critical habitat rule. No changes were required for our
economic analysis after considering public comments; however, we
updated the screening memo to reflect relevant changes necessary for
addressing recent Executive Orders as well as the updated unit
descriptions, described below. These minor updates did not result in
any changes to the overall findings of the screening memo; thus, we
consider the July 3, 2025, economic analysis as final (Industrial
Economics, Incorporated (IEc) 2025, entire). We made many small,
nonsubstantive changes throughout this document that do not affect the
designations (e.g., making minor edits for clarity throughout the rule,
updating references to enacted and rescinded Executive Orders and
Department of the Interior Secretary's Orders). Below is a summary of
changes made in this final rule.
(1) We made minor edits to the Summary of Essential Physical or
Biological Features to clarify which physical or biological features
are essential to the conservation of each species in an effort to
resolve confusion expressed during the public comment period.
Specifically, we added explicit statements about which substrate types
are considered suitable habitat for each species using information that
was presented in table 1 of the Physical or Biological Features
Essential to the Conservation of the Species section of the proposed
critical habitat rule (89 FR 101100 at 101105; December 13, 2024).
(2) In an effort to resolve confusion expressed during the public
comment period, we made minor edits to the Criteria Used to Identify
Critical Habitat section to clarify the methodology used to identify
areas as critical habitat for each species. During the public comment
period, multiple commenters were confused about the application of
``risk'' terminology in the Criteria Used to Identify Critical Habitat
compared to the ``risk'' evaluation described in the SSA report. In the
proposed rule, the term ``risk'' was used in a general sense of the
term to describe what was meant by a ``high-condition'' or ``moderate-
condition'' population, in plain language, rather than indicate
identified risks acting on a population as described in the SSA report.
This unintentional conflation of terms resulted in some confusion
around how we delineated critical habitat units. As such, in this final
rule, we removed the term ``risk'' from our methodology to reduce
confusion and better convey our approach for defining areas as critical
habitat.
(3) We extended the critical habitat designation for rayed bean
(RABE) 9: Allegheny River to include additional areas upstream of the
proposed designation in areas that are considered to be occupied by the
species and that contain the physical or biological features based on
information we received during the comment period. Specifically, we
extended the critical habitat designation in the Allegheny River
upstream from its confluence with Oswayo Creek near Portville
(Cattaraugus County, New York) to the Allegheny River's confluence with
Sartwell Creek near Burtville (McKean County, Pennsylvania). We also
extended the critical habitat designation in Oswayo Creek upstream from
the New York/Pennsylvania State Line in Allegany County, New York, and
McKean County, Pennsylvania, upstream to Oswayo Creek's confluence with
Honeoye Creek in Potter County, Pennsylvania. Finally, we added Honeoye
Creek from its confluence with Oswayo Creek upstream to the New York/
Pennsylvania State Line in Allegany County, New York, and Potter
County, Pennsylvania. In total, these revisions to RABE 9 result in an
increase of approximately 49 river miles (rmi) (79 river kilometers
(rkm)) of critical habitat from the areas we proposed.
(4) We extended the critical habitat designation for RABE 10:
Middle Allegheny River to include additional stream segments upstream
and downstream of the proposed designation in areas that are considered
to be occupied by the species and that contain the physical or
biological features, based on information we received during the
comment period. Specifically, we added Oil Creek from the Oil Creek
State Park Ice Control Dam in Venango County, Pennsylvania, downstream
to Oil Creek's confluences with the Allegheny River in Oil City
(Venango County, Pennsylvania). Additionally, we extended critical
habitat downstream in the Allegheny River from its previous terminus at
Lock and Dam Number 5 in Armstrong County, Pennsylvania, downstream to
the Allegheny River's mouth at the Kiskiminetas River in Armstrong
County, Pennsylvania. These revisions to RABE 10 result in an increase
of approximately 8 rmi (13 rkm) of critical habitat from the areas we
proposed.
(5) We updated the unit description for RABE 15: Tippecanoe River
within the preamble and the regulatory text and updated the map within
the regulatory text. Specifically, we divided RABE 15: Tippecanoe River
into two subunits within a larger unit instead of describing it all as
a single unit; however, the overall designation did not change. As
written in the proposed rule, the critical habitat designation excluded
Lakes Shafer and Freeman and the stretch of the Tippecanoe River
between the two lakes, which resulted in two disjunct portions of
critical habitat on the Tippecanoe River--now referred to as subunits.
Although the unit description did not include the two lakes and the
stretch of the Tippecanoe River as critical habitat (i.e., this area
was excluded by text), this segment was inadvertently included within
the regulatory maps of the proposed rule (89 FR 101100 at 101148-
101149). We updated the map in this final rule to show only the
subunits as critical habitat within RABE 15: Tippecanoe River.
(6) We updated the unit description for snuffbox (SNBO) 2:
Embarrass River within the preamble and the regulatory text by dividing
the unit into two subunits instead of describing it all as a single
unit; however, the overall designation did not change. As written in
the proposed rule, the unit description was not clear that there was a
break within the critical habitat unit that corresponds to Caroline
Pond 247 in Shawano County, Wisconsin. As such, we updated the unit
description so that subunit SNBO 2a contains the South Fork Embarrass
River portion of the unit and subunit SNBO 2b contains the Embarrass
River and North Fork Embarrass River portions of the unit. We updated
the unit map within the regulatory text to show the subunit
designations.
(7) We updated the unit description for SNBO 9: French Creek within
the preamble and the regulatory text and updated the unit map within
the regulatory text. Specifically, we divided

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SNBO 9: French Creek into two subunits within a larger unit instead of
describing it all as a single unit; however, the overall designation
did not change. As written in the proposed rule, the unit description
was not clear that there was a break in the area designated as critical
habitat within the mainstem of the French Creek that corresponds with
areas that are not considered to be occupied by the species and that do
not contain the physical or biological features essential to the
conservation of the species as a result of impounded habitat for Union
City Lake. As such, we updated the unit description within this final
rule to describe two subunits. SNBO 9 subunit A contains the areas
designated as critical habitat upstream of Union City Lake, and SNBO 9
subunit B contains the areas downstream of the Union City Dam that
creates Union City Lake. With regard to the unit map, despite the West
Branch French Creek being included in the proposed unit descriptions,
this segment was inadvertently omitted from the map within the proposed
rule's regulatory text (89 FR 101100 at 101169; December 13, 2024). We
updated the unit map to show the area designated as critical habitat
within the West Branch French Creek.
(8) We updated the critical habitat designation for SNBO 13: Little
Kanawha River by removing a portion of the Little Kanawha River from
its confluence with the Hughes River downstream to the Little Kanawha
River's confluence with the Ohio River in Parkersburg (Wood County,
West Virginia). Based on information we received during the comment
period, this stretch of the Little Kanawha River is not considered to
be either historically or currently occupied habitat for the snuffbox
as it does not contain the physical or biological features essential to
the conservation of the species and is heavily impacted by siltation.
Thus, this area does not meet our definition of critical habitat. The
updated SNBO 13 designation now terminates at the confluence of the
Little Kanawha River and the Hughes River near Greencastle (Wirt
County, West Virginia), but it still includes the Hughes River portion
of the designation. This revision to SNBO 13 results in a decrease of
approximately 18 rmi (29 rkm) from the areas we proposed.
(9) We updated the critical habitat designation for SNBO 14:
Kanawha River by removing the upstream portion of the Elk River between
Sutton Dam in Braxton and Webster Counties, West Virginia, and the
Pisgah Ridge Road/Elk Street crossing near the town of Clay (Clay
County, West Virginia). Based on information we received in the comment
period, this portion of the Elk River is not considered to be
historically or currently occupied by the species. Despite apparent
suitability and the lack of significant movement barriers, the lack of
known records within this stretch of river indicates that some unknown
environmental factors are limiting the ability of this river segment to
support the species. As such, this area does not meet our definition of
critical habitat for snuffbox. The updated SNBO 14 now begins at the
Pisgah Ridge Road/Elk Street crossing near Clay (Clay County, West
Virginia), and extends downstream in the area we proposed. This
revision to SNBO 14: Kanawha River results in a decrease of
approximately 49 rmi (79 rkm) from the areas we proposed.
(10) We extended the critical habitat designation for SNBO 16:
Little Darby Creek further downstream in occupied areas where the
physical or biological features are present, based on information we
received during the comment period. The proposed unit stopped at the
U.S. Highway 40 Bridge crossing near the village of West Jefferson
(Madison County, Ohio); however, the unit now extends downstream to the
Little Darby Creek's confluence with the Big Darby Creek (Franklin
County, Ohio). This revision to SNBO 16: Little Darby Creek results in
an increase of approximately 7 rmi (11 rkm) from the areas we proposed.
(11) We extended the critical habitat designation for SNBO 17: Big
Darby Creek further downstream in occupied areas where the physical or
biological features are present, based on information we received
during the comment period. The proposed unit stopped at the State
Highway 665 Bridge west of the unincorporated community of Darbydale
(Franklin County, Ohio); however, it now extends downstream to the Big
Darby Creek's confluence with the Scioto River near the city of
Circleville (Pickaway County, Ohio). This revision of SNBO 17: Big
Darby Creek results in an increase of approximately 31 rmi (50 rkm)
from the areas we proposed.
(12) We updated the unit description for SNBO 27: Tippecanoe River
within the preamble and the regulatory text and updated the map within
the regulatory text. Specifically, we divided SNBO 27: Tippecanoe River
into two subunits within a larger unit instead of describing it all as
a single unit; however, the overall designation did not change. As
written in the proposed rule, the critical habitat designation excluded
Lakes Shafer and Freeman and the stretch of the Tippecanoe River
between the two lakes, which resulted in two disjunct portions of
critical habitat on the Tippecanoe River--now referred to as subunits.
Although the unit description did not include the two lakes and the
stretch of the Tippecanoe River as critical habitat (i.e., this area
was excluded by text), this segment was inadvertently included within
the regulatory maps of the proposed rule (89 FR 101100 at 101184-
101185). We updated the map in this final rule to show only the
subunits as critical habitat within SNBO 27: Tippecanoe River.
(13) We made minor updates to all unit descriptions to reflect
changes in the status (i.e., proposed or final) of critical habitat
designations to reflect the best scientific data available at the time
of publication for this final rule.
(14) We updated the spectaclecase (SPCA) 9: Clinch River Unit to
resolve a mapping error that overestimated the actual river mileage of
the designation. This update resulted in an approximately 3 river mile
(5 river kilometer) decrease in the total critical habitat for that
unit and the overall total designation for spectaclecase. Given the
overlap of this unit with the other designations, the total amount of
unique river miles in the designation across the four species remains
unchanged.
(15) We updated each species' critical habitat unit description
summary tables (table 2 through table 5, below) to include a summary of
approximate river mileage by land ownership type (i.e., Federal, State,
Local). Within the proposed rules, these tables only reported river
mileages by Public and Private land ownership types.

Summary of Comments and Recommendations

In the proposed rule published on December 13, 2024 (89 FR 101100),
we requested that all interested parties submit written comments on the
proposal by February 11, 2025. We also contacted appropriate Federal
and State agencies, Tribal entities, scientific experts and
organizations, and other interested parties and invited them to comment
on the proposal. Newspaper notices inviting general public comment were
published in USA Today on December 20, 2024. 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.

Federal Agency Comments

(1) Comment: One Federal Agency requested that we exclude critical
habitat under section 4(b)(2) of the Act.

[[Page 22593]]

Specifically, they requested that portions of Unit SPCA 2 (in the
Mississippi River) that are ``not suitable habitat'' for the
spectaclecase mussel be excluded from the critical habitat designation;
the agency commented that excluding areas of ``not suitable habitat''
would reduce the burden placed on project proponents in evaluating
areas which are known to not provide any additional protection for the
species.
Our response: The Act requires the Service to designate critical
habitat for listed species to the maximum extent prudent and
determinable and does not restrict such designation to particular land
ownership. Rather, areas that meet the definition of critical habitat,
as determined on the basis of the best scientific data available, are
proposed for designation. However, section 4(b)(2) of the Act further
provides that the Secretary, in designating critical habitat and making
revisions, shall take into consideration the economic impact, the
impact on national security, and any other relevant impact of
specifying any particular area as critical habitat. According to our
Policy Regarding Implementation of Section 4(b)(2) of the Endangered
Species Act (81 FR 7226; February 11, 2016), we consider six elements
when considering whether or not to exclude an area from critical
habitat: (1) partnerships and conservation plans; (2) conservation
plans permitted under section 10 of the Act; (3) national security and
homeland security impacts; (4) Tribal lands; (5) Federal lands; and (6)
economic impacts. The Secretary may then choose to exercise their
discretion to exclude any area from critical habitat if they determine
that the benefit of exclusion outweighs the benefits of specifying such
areas as part of the critical habitat, unless that exclusion would
result in the extinction of the species. Under the Services' Policy
Regarding Implementation of Section 4(b)(2) of the Endangered Species
Act (81 FR 7226; February 11, 2016), a proponent of such an exclusion
must provide a reasoned rationale for such exclusion, including
measures undertaken to conserve species and habitat on the land at
issue (such that the benefit of inclusion is reduced).
Regarding the request for the Secretary to use their discretion to
exclude areas of ``not suitable habitat'' of Unit SPCA 2 in the
Mississippi River from the critical habitat designation for
spectaclecase this unit is occupied by the species and contains the
physical or biological features essential to the conservation of the
species. Moreover, habitat for and evidence of the species has been
found within the navigation channel and throughout the large pools
within the unit. The commenter did not provide any information to
support their request to remove areas because they are ``not suitable
habitat.'' These areas are occupied by the species and any
discretionary Federal action would need to comply with the provisions
of section 7(a)(2) as required under the Act. Accordingly, we did not
exclude areas within Unit SPCA 2 from the critical habitat designation.

Comments From States

(2) Comment: For sheepnose, the West Virginia Division of Natural
Resources and multiple public commenters requested additional critical
habitat across the species' range. They provided information in support
of adding entire units, extending critical habitat upstream or
downstream of proposed units, or both. Specifically, we received a
request from the West Virginia Division of Natural Resources to
consider adding critical habitat within the Ohio River along the border
of West Virginia and Ohio within populations identified in the SSA
report (i.e., Raccoon-Symmes, Upper Ohio-Shade, Little Muskingum-Middle
Island) and the Kanawha River in West Virginia from Kanawha Falls
downstream to the Town of Deepwater. Additionally, we received requests
from public commenters to consider adding critical habitat within the
Ohio River along the border of Illinois, Indiana, Kentucky, Ohio, and
West Virginia within populations identified in the SSA report (i.e.,
Lower Ohio, Lower Ohio-Little Pigeon, Silver-Little Kentucky, Ohio
Brush-Whiteoak, Little Scioto-Tygarts, Raccoon-Symmes, Upper Ohio-
Shade, Little Muskingum-Middle Island); and the Mississippi River from
its confluence with the Chippewa River downstream through Pool 5. As
part of these requests, commenters noted a lack of sampling effort in
these larger waterbodies (e.g., the Ohio River) and the importance of
maintaining connectivity of mussels and their fish hosts between
disjunct tributaries through the mainstems of these larger, navigable
waterbodies.
Our response: Critical habitat is one of the many tools that
supports the continued conservation of imperiled species by guiding
cooperation within the Federal government. While the intent of
designating critical habitat is to identify specific areas that are
indispensable to the conservation of a species, it is important to note
that the lack of critical habitat does not preclude coordination and
implementation of recovery actions. Our decisions on whether or not to
adjust critical habitat, summarized below, are supported by the best
available science to identify areas that contain the physical or
biological features essential to the conservation of the species, as
outlined in our methodology. Additionally, we recognize that the
implementation of multiple tools across additional populations, as
outlined in the recovery plan for these four species, will be crucial
to achieve species' recovery. We assessed all literature and data
provided during the public comment period. In most instances, these
data were redundant with information that was considered as part of the
SSA report (Service 2022b, entire), the recovery plan for these four
species of freshwater mussels (Service 2024, entire), or both, which
formed the basis of our critical habitat designation. Several comments,
however, pertained to decisions associated with the cumulative
population size and reproduction and recruitment metrics outlined in
Appendix C of the sheepnose's SSA report (Service 2022b, pp. C-1-C-4)
and a few of these comments provided new data that we incorporated into
our considerations for this final rule.
We identified critical habitat for sheepnose based on the physical
or biological features essential to the conservation of sheepnose and
considering the data provided for and population conditions estimated
within the sheepnose SSA (Service 2022b, entire), the four mussel
recovery plan (Service 2024, entire), and the public comment period for
the proposed rule (89 FR 101100; December 13, 2024). All population
conditions were estimated in accordance with the best scientific data
available, and expert opinions were integrated under certain
conditions, as discussed in Appendix C of the SSA report (Service
2022b, pp. C-1-C-4). Condition category assignments were otherwise
data-driven for a comparative approach across populations, resulting in
instances where text descriptions capturing expert opinions within the
SSA report may not exactly align with the assessed Current Demographic
Condition category or subcategories for a given population.
After assessing all additional data received during the public
comment period in conjunction with the data used to develop the
proposed designation of critical habitat (89 FR 101100; December 13,
2024), we determined that in all instances--except for one--the data
were duplicative of information that we already considered or did not
result in a change in the current demographic condition of the
population. As such, these data do not result in changes that meet our
criteria

[[Page 22594]]

for considering portions of the Ohio River (Lower Ohio, Lower Ohio-
Little Pigeon, Silver-Little Kentucky, Ohio Brush-Whiteoak, Little
Scioto-Tygarts, Upper Ohio-Shade, Little Muskingum-Middle Island),
upper Mississippi River from its confluence with the Chippewa River
downstream through Pool 5 (Buffalo-Whitewater), or the Kanawha River in
West Virginia from Kanawha Falls downstream to the Town of Deepwater
(Upper Kanawha) as critical habitat for the sheepnose.
For the Raccoon-Symmes population, however, we received data that
resulted in the current demographic condition for this population
changing from ``low'' to ``moderate'' due to the updated information
documenting the collection of a juvenile individual in 2020. Although
the demographic condition of this population improved, we have
determined that this population does not meet our criteria to consider
the Raccoon-Symmes portion of the Ohio River as critical habitat for
sheepnose. While the ``moderate'' demographic condition of this
population warrants that we consider this population on a case-by-case
basis under the second criteria of our methodology--outlined in the
Methodology Used for Selection of Critical Habitat Units section,
below--the lack of connectivity of this population to other areas of
high or moderate demographic condition or overlap with other areas of
existing critical habitat precludes its inclusion as critical habitat.
We agree with commenters that portions of the Ohio River--and other
large rivers--remain largely under-sampled, and we recognize that
systemic survey efforts range-wide are generally lacking, both of which
result in unknowns associated with the current status of many
populations. In development of the SSA and recovery plan for these four
mussel species, we relied on data provided by State natural resource
agencies and Service field offices to inform the metrics used to assess
the current demographic conditions of each population. Additionally, we
requested that State agency partners provide a technical review of the
defined current demographic condition and population description,
presented in both the SSA report and the recovery plan, for the
respective populations occurring within their areas of management to
ensure that available data reflected observed conditions.
Finally, while we agree that mainstem reaches are important for
allowing movement of host fish and genes between populations in
disjunct tributaries to maintain demographic and genetic health (i.e.,
genetic variability and adaptive capacity) of populations, these
mainstem areas do not meet our criteria for designation of critical
habitat. We included mainstem reaches (e.g., the Lower Tennessee River)
where appropriate, regardless of navigability status, where they met
the definition of critical habitat. In the case of the Ohio River and
the upper Mississippi River units that were requested for addition,
available data did not support the classification of these areas as
having comparatively large populations with evidence of sizeable levels
of regularly occurring reproduction over time with high recovery
potential. These areas do not overlap with existing critical habitat or
occupied areas for other listed species, and these areas do not contain
unique habitats that would contribute meaningfully to adaptive capacity
of the species. While these areas are important for the sheepnose, they
do not meet our criteria for inclusion as critical habitat within this
final designation. Although they may be important for the recovery of
sheepnose (along with other areas of suitable habitat), they do not
meet the definition of critical habitat.
The occupied areas that meet the definition of critical habitat for
sheepnose contain the physical or biological features essential to the
conservation of the species and meet the Criteria Used to Identify
Critical Habitat, described below. This subset of areas is also
supported by the sheepnose's recovery plan, which identifies areas that
support the healthiest remaining populations, have high recovery
potential, and support genetically distinct populations that are
important for the conservation and recovery of sheepnose.

Public Comments

(3) Comment: For rayed bean, some commenters requested that we
expand areas of critical habitat within Little Darby Creek and Big
Darby Creek in Ohio, stating that despite the lack of recent rayed bean
records, the presence of other mussel species within these waterbodies
suggests that inclusion of these areas should be considered.
Our response: As described in our response to comment (2), above,
we used the rayed bean SSA report (Service 2022a, entire) and the
recovery plan for these four species of freshwater mussels (Service
2024, entire), and we based the critical habitat designations on the
best scientific information available. We assessed all data provided
during the public comment period. Although the commenters provided
information that documented the presence of the rayed bean within these
river segments, the records provided were from the historical period
(i.e., prior to the year 2000), and thus the areas requested for
addition are not considered to be occupied at the time of listing.
Although these areas may be important for the rayed bean (in
addition to other areas of potentially suitable habitat), the occupied
areas that meet the definition of critical habitat for rayed bean
contain the physical or biological features essential to the
conservation of the species and meet the Criteria Used to Identify
Critical Habitat, described below. This subset of occupied areas
supports the rayed bean's recovery plan, which identifies areas that
support the healthiest remaining populations, have high recovery
potential, and support genetically distinct populations that are
important for the conservation and recovery of species. We are not
designating any areas outside the geographical area occupied by the
species because we have not identified any unoccupied areas that meet
the definition of critical habitat, and we have determined that
occupied areas are sufficient to conserve the rayed bean. As such, we
are not expanding areas of critical habitat within Little Darby and Big
Darby Creeks because they do not meet our criteria for inclusion as
critical habitat.
(4) Comment: For snuffbox, multiple public commenters requested
additions or expansions of the critical habitat designation across the
species' range. Specifically, we received requests for adding critical
habitat within the Mississippi River below Lock and Dam 1 and expanding
critical habitat within the Middle Fork Kentucky River and Red Bird
River in Kentucky.
Our response: As described in our response to comment (2), above,
we used the snuffbox SSA report (Service 2022c, entire) and the
recovery plan for these four species of freshwater mussels (Service
2024, entire). We assessed all data provided during the public comment
period. Although these data provided some additional records in the
Middle Kentucky River and the Red Bird River, these observations were
either redundant with the records considered as part of the SSA report,
recovery plan, or were historical observations for the species. In the
instance of the upper Mississippi River, while we agree that the
snuffbox is present within this segment, its demographic condition is
considered to be ``low'' with a ``high'' risk based on the SSA report
(Service 2022c, pp. 28-30), and the provided information did not change
that categorization. Although these areas may be important for the

[[Page 22595]]

snuffbox (in addition to other areas of potentially suitable habitat),
the occupied areas that meet the definition of critical habitat for
snuffbox contain the physical or biological features essential to the
conservation of the species and meet the Criteria Used to Identify
Critical Habitat, described below. This subset of occupied areas
supports the snuffbox's recovery plan, which identifies areas that
support the healthiest remaining populations, have high recovery
potential, and support genetically distinct populations that are
important for the conservation and recovery of species.
We are not designating any areas outside the geographical area
occupied by the species because we have not identified any unoccupied
areas that meet the definition of critical habitat, and we have
determined that occupied areas are sufficient to conserve the snuffbox.
Within the species' recovery plan, we outline that recovery can be
achieved by protecting and maintaining or enhancing existing occupied
areas, with no need to create or establish new habitat areas or
populations for snuffbox. As such, we determined that the areas that
are suggested for inclusion as critical habitat are not known to be
occupied by the species or do not meet our criteria for inclusion as
critical habitat and thus were not identified as such.
(5) Comment: Multiple commenters requested that the Service
consider unoccupied areas of critical habitat for each species,
suggesting that the proposed critical habitat designation was not
sufficient to protect the species.
Our response: We did not propose to designate any areas outside of
the geographical area currently occupied by the species because we did
not find any unoccupied areas to be essential for the conservation of
the species. Based upon the recently completed recovery plan for the
species, we have determined that the designation of critical habitat
within the areas currently designated across the physiographic
representation of each species' range will be sufficient to conserve
the species. Efforts to improve the resiliency of populations in
currently occupied streams, as discussed in the recovery plan, should
increase viability to the point that protections of the Act are no
longer necessary.
(6) Comment: Multiple commenters suggested that the Service
consider including additional areas as critical habitat that are
adjacent to the proposed designation as these areas could impact the
proposed critical habitat. Multiple commenters requested that we
include additional areas upstream of proposed critical habitat.
Specifically, one public commenter requested that critical habitat
boundaries should be expanded to include riparian buffers, rather than
limiting the designation of critical habitat to bank-full heights. In
all instances, the commenters stated that alterations to riparian
areas, headwater areas, or both could result in decreased suitability
of designated critical habitat as a result of water quality or
sedimentation impacts.
Our response: Critical habitat includes areas that contain the
physical or biological features essential to the conservation of the
species, and which may require special management considerations or
protection. We have identified those physical or biological features as
adequate flows or suitable hydrological flow regimes, suitable
substrates and connected instream habitats, adequate water and sediment
quality, and the presence and abundance of suitable host fish (physical
or biological features are described in more detail in the Summary of
Essential Physical or Biological Features section, below). Although
adjacent terrestrial areas may be important to maintaining the species'
habitats, terrestrial areas would not themselves contain those aquatic
features. Therefore, we are not including the terrestrial areas in the
critical habitat designations.
We acknowledge that degradation to upstream reaches or riparian
areas may affect downstream or within-stream areas of aquatic critical
habitat. Actions with a federal nexus that may affect designated
critical habitat would be considered through the Act's section 7
consultation processes. However, we also note and describe in the
economic screening analysis that all areas designated as critical
habitat for these four species of mussels are occupied; thus, section 7
consultation by Federal action agencies is already required for any
activities that may affect the mussels regardless of critical habitat
designation.
In recognition of the additional requirement in the Section 7
consultation associated with consideration of critical habitat, the
costs of this additional layer of compliance due to the presence of
critical habitat is quantified in the economic screening analysis.
Because section 7 consultations would occur for projects with a Federal
nexus that are planned within the critical habitat area anyway given
that they are all occupied, there are already measures that would be
implemented to avoid jeopardy to the species. Those measures that avoid
jeopardy due to habitat impacts to the species are also likely to avoid
adverse modification to critical habitat, minimizing any impact from
the consultations on critical habitat. Indeed, we anticipate little to
no additional section 7 consultations due solely to the designation of
critical habitat and no new measures resulting from consultation on the
critical habitat. Nevertheless, in our screening analysis for these
mussels, we acknowledge the increased complexity of Section 7
consultations that consider critical habitat in addition to the species
presence and quantify that administrative burden.
(7) Comment: One commenter suggested that the Service include in
the economic analysis consideration of the economic benefits of
protecting critical habitat for the four mussel species, including
ecosystem services, the protection of clean water, the reduced cost of
water treatment for drinking water supplies, as well as public health
and recreational benefits.
Our response: The primary intended benefit of critical habitat is
to support the conservation of endangered and threatened species, such
as the rayed bean, sheepnose, snuffbox, and spectaclecase mussels. In
order to quantify and monetize direct benefits of the designation,
information would be needed to determine (1) the incremental change in
the probability of conservation of these four species that is expected
to result from the critical habitat designation, and (2) the public's
willingness to pay for such beneficial changes. Because of the
uncertainties associated with monetary quantification of these benefits
and uncertainty in additional efforts to conserve any of these four
species, we were not able to estimate the economic benefits of
ecosystem services, such as clean water via mussel-based biofiltration
treatment, or of broad benefits of ecosystem services that flow from
the critical habitat areas to human populations.
(8) Comment: One public commenter requested that we exclude
critical habitat under section 4(b)(2) of the Act. Specifically, they
requested that the Service consider excluding all agricultural and
cultivated lands within the state of Tennessee from the proposed
designation of critical habitat for sheepnose, snuffbox, and
spectaclecase mussels. They stated that agriculture is the number one
contributor to Tennessee's economy--accounting for 7.8 percent of the
State's economic activity--and suggested that taking land out of
production for use as critical habitat will reduce farmers' available
resources to grow products, thus increasing the economic burden.

[[Page 22596]]

Our response: We are only designating aquatic areas as critical
habitat up to the ordinary high water mark; no areas used for
agriculture or cultivation are included in the critical habitat
designations. Furthermore, private activities without a federal nexus
are not subject to additional restrictions due to critical habitat.
Routine private land uses, like farming, ranching, timber harvest, and
construction, carried out on private land without federal involvement
are unaffected by critical habitat designations. Most agricultural
activities do not have a Federal nexus, and there are no large-scale
Federal irrigation projects in the range of these species. In those
limited cases where agricultural activities have had a Federal nexus
and have triggered consultation under section 7, there have been no
formal consultations (i.e., all consultations have concluded with a
``may affect but are not likely to adversely affect'' determination).
Thus, we do not anticipate any agricultural areas being taken out of
production or otherwise restricted due to this designation.
(9) Comment: Multiple commenters expressed concerns that these
critical habitat designations would impose restrictions on private
lands, or public lands, and result in loss of access to or ability to
use areas designated as critical habitat. One commenter expressed
specific concerns that such restrictions would take areas that are
currently agricultural and cultivated lands out of production and would
result in decreased agricultural productivity.
Our response: Under the Act, the only regulatory effect of a
critical habitat designation is that Federal agencies must ensure their
actions are not likely to destroy or adversely modify critical habitat
under section 7 of the Act. 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. Critical habitat
designation also does not establish specific land management standards
or prescriptions, although Federal agencies are prohibited from
carrying out, funding, or authorizing actions that would destroy or
adversely modify critical habitat. Destruction or adverse modification
means a direct or indirect alteration that appreciably diminishes the
value of critical habitat for the conservation of a listed species.
Most projects that impact critical habitat do not destroy or adversely
modify it. In those limited cases where the proposed action would
destroy or adversely modify the critical habitat, the Service is
required to identify reasonable and prudent alternatives to the
proposed action that would avoid destruction and adverse modification.
Reasonable and prudent alternatives must be economically and
technologically feasible and implemented in a manner consistent with
the intended purposes of the action.
The designation of critical habitat does not prevent access to any
land, whether private, tribal, State or Federal. Critical habitat
receives protection only under section 7 of the Act and only directs
Federal agencies to 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. Lastly, the areas designated as critical
habitat only include aquatic habitat up to the ordinary high water
mark; adjacent, terrestrial riparian areas (i.e., those areas used for
agriculture or cultivation) are not included as part of the critical
habitat designations. Therefore, these final designations of critical
habitat will not remove agricultural and cultivated lands from
production and will not result in loss of access to areas of private or
public lands.
(10) Comment: One commenter provided information that supports the
effectiveness of forestry best management practices (BMPs) on reducing
sedimentation and erosion and protecting aquatic biota. The commenter
recommended that we include this information in the final rule.
Our response: We identified the use of BMPs to reduce
sedimentation, erosion, and bank destruction as one of the management
activities that could ameliorate those threats to the physical or
biological features in Special Management Considerations or Protection
in the proposed rule (see 89 FR 101100 at 101106, December 13, 2024)
and in the same discussions (below) in this final rule.

I. Critical Habitat

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(5)(A) 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' lifecycle, even if not used on a regular basis (e.g.,
migratory corridors, seasonal habitats, and habitats used periodically,
but not solely by vagrant individuals).
Conservation, as defined under section 3(3) of the Act, means to
use and the use of all methods and procedures that are necessary to
bring an endangered or threatened species to the point at which the
measures provided pursuant to the Act are no longer necessary. Such
methods and procedures include, but are not limited to, all activities
associated with scientific resources management such as research,
census, law enforcement, habitat acquisition and maintenance,
propagation, live trapping, and transplantation, and, in the
extraordinary case where population pressures within a given ecosystem
cannot be otherwise relieved, may include regulated taking.
Critical habitat receives protection under section 7 of the Act
through the requirement that each Federal action agency ensure, in
consultation with the Service, that any action they authorize, fund, or
carry out is not likely to result in the destruction or adverse
modification of designated critical habitat. The designation of
critical habitat does not affect land ownership or establish a refuge,
wilderness, reserve, preserve, or other conservation area. Such
designation also does not allow the government or public to access
private lands. Such designation does not require implementation of
restoration, recovery, or enhancement measures by non-Federal
landowners. Rather, designation requires that, where

[[Page 22597]]

a landowner requests Federal agency funding or authorization for an
action that may affect an area designated as critical habitat, the
Federal agency consult with the Service under section 7(a)(2) of the
Act. If the action may affect the listed species itself (such as for
occupied critical habitat), the Federal action agency would have
already been required to consult with the Service even absent the
designation because of the requirement to ensure that the action is not
likely to jeopardize the continued existence of the listed species.
Even if the Service were to conclude after consultation that the
proposed activity is likely to result in destruction or adverse
modification of the critical habitat, the Federal action agency and the
landowner are not required to abandon the proposed activity, or to
restore or recover the species; instead, they must implement
``reasonable and prudent alternatives'' to avoid destruction or adverse
modification of critical habitat. By definition (50 CFR 402.02),
reasonable and prudent alternatives are not allowed to make projects
infeasible (see response to comment 9).
Under the first prong of the Act's definition of critical habitat,
areas within the geographical area occupied by the species at the time
it was listed are included in a critical habitat designation if they
contain physical or biological features (1) which are essential to the
conservation of the species and (2) which may require special
management considerations or protection. For these areas, critical
habitat designations identify, to the extent known using the best
scientific data available, those physical or biological features that
are essential to the conservation of the species (such as space, food,
cover, and protected habitat).
Under the second prong of the Act's definition of critical habitat,
we can designate critical habitat in areas outside the geographical
area occupied by the species at the time it is listed, upon a
determination that such areas are essential for the conservation of the
species.
Section 4(b)(2) 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 compiled in the SSA report and information developed during
the listing process for the species. Additional information sources may
include any generalized conservation strategy, criteria, or outline
that may have been developed for the species; the recovery plan for the
species; articles in peer-reviewed journals; conservation plans
developed by States and counties; scientific status surveys and
studies; biological assessments; other unpublished materials; or
experts' opinions or personal knowledge.
A critical habitat designation does not signal that habitat outside
the designated area is unimportant or may not be needed for recovery of
the species. Areas that are important to the conservation of the
species, both inside and outside the critical habitat designation, will
continue to be subject to: (1) Conservation actions implemented under
section 7(a)(1) of the Act; (2) regulatory protections afforded by the
requirement in section 7(a)(2) of the Act for Federal agencies to
ensure their actions are not likely to jeopardize the continued
existence of any endangered or threatened species; and (3) the
prohibitions found in section 9 of the Act. These protections and
conservation tools will continue to contribute to recovery of the
species. Similarly, critical habitat designations made on the basis of
the best scientific data available at the time of designation will not
control the direction and substance of future recovery plans, habitat
conservation plans (HCPs), or other species conservation planning
efforts if new information available at the time of those planning
efforts calls for a different outcome.

Physical or Biological Features Essential to the Conservation of the
Species

In accordance with section 3(5)(A)(i) of the Act and regulations at
50 CFR 424.12(b), in determining which areas we will designate as
critical habitat from within the geographical area occupied by the
species at the time of listing, we consider the physical or biological
features that are essential to the conservation of the species and
which may require special management considerations or protection. The
regulations at 50 CFR 424.02 define ``physical or biological features
essential to the conservation of the species'' as the features that
occur in specific areas and that are essential to support the life-
history needs of the species, including, but not limited to, water
characteristics, soil type, geological features, sites, prey,
vegetation, symbiotic species, or other features. A feature may be a
single habitat characteristic or a more complex combination of habitat
characteristics. Features may include habitat characteristics that
support ephemeral or dynamic habitat conditions. Features may also be
expressed in terms relating to principles of conservation biology, such
as patch size, distribution distances, and connectivity. For example,
physical features essential to the conservation of the species might
include gravel of a particular size required for spawning, alkaline
soil for seed germination, protective cover for migration, or
susceptibility to flooding or fire that maintains necessary early-
successional habitat characteristics. Biological features might include
prey species, forage grasses, specific kinds or ages of trees for
roosting or nesting, symbiotic fungi, or absence of a particular level
of nonnative species consistent with conservation needs of the listed
species. The features may also be combinations of habitat
characteristics and may encompass the relationship between
characteristics or the necessary amount of a characteristic essential
to support the life history of the species.
In considering whether features are essential to the conservation
of the species, we may consider an appropriate quality, quantity, and
spatial and temporal arrangement of habitat characteristics in the
context of the life-history needs, condition, and status of the
species. These characteristics include, but are not limited to, space
for individual and population growth and for normal behavior; food,
water, air, light, minerals, or other nutritional or physiological
requirements; cover or shelter; sites for breeding, reproduction, or
rearing (or development) of offspring; and habitats that are protected
from disturbance.

General Mussel Biology

Freshwater mussels, including the rayed bean, sheepnose, snuffbox,
and spectaclecase mussels, have a complex life history that involves
parasitic larvae, called glochidia, which are wholly reliant on host
fish(es). As adult

[[Page 22598]]

freshwater mussels are generally sessile, suspension-feeders that spend
their entire lives partially or completely buried within the substrate
(Call 1900, p. 459; Watters 1994, p. 105; West et al. 2000, p. 251),
dispersal occurs solely through the behavior of their host fish(es).
Mussels are broadcast spawners; males release sperm into the water
column, which is taken in by the female. Fertilized eggs develop into
microscopic larvae called glochidia within special gill chambers on the
female mussel and remain with the female until they are mature and
ready for release as glochidia, to attach to their host fish(es) (Haag
2012, pp. 37-42).
Glochidia will perish if they fail to attach to a suitable 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 (Neeves
1991, p. 254; Bogan 1993, p. 599). Successful glochidia encyst (enclose
in a cyst-like structure) on the host's tissue, draw nutrients from the
host's tissue, and develop into juvenile mussels (Arey 1932, pp. 214-
215). After a period of time when the glochidia transform into
juveniles, they will excyst (drop off) from the fish and drop to the
substrate on the bottom of the stream. Juveniles that drop in
unsuitable substrates perish because their immobility prevents them
from relocating to more favorable habitat. Juveniles burrow into
interstitial substrates and grow to larger sizes that are less
susceptible to predation and displacement from high-flow events (Yeager
et al. 1994, p. 220). Adult mussels remain within the same general
location where they excysted from their host fish as juveniles.

Habitat Conditions, Suitable Substrates, and Flow Conditions

All life stages of the rayed bean, sheepnose, snuffbox, and
spectaclecase mussels require flowing water for survival. In general,
all four species occur within small- to medium-sized creeks, to larger
rivers, with rayed bean and snuffbox occasionally occurring along wave-
washed shores of lakes (Call 1900, p. 459; Ortman 1919, p. 68;
Stansbery 1967, entire; Buchanan 1980, p. 13; Neeves 1991, pp. 280-281;
Cummings and Mayer 1992, pp. 50, 142, 162; Watters 1994, p. 105; Oesch
1995, p. 121; Parmalee and Bogan, 1998; pp. 50, 77, 108, 177, 244;
Baird 2000, p. 5-6; West et al. 2000, pp. 251, 253; Badra 2002, pers.
comm.; Butler 2002, p. 6; Williams et al. 2008, p. 498; Jones et al.
2019, p. 205). Within these areas, rayed bean typically occur in or
near shoal or riffle (short, shallow length of stream where the stream
flows more rapidly) areas and in the shallow wave-washed areas of
glacial lakes over gravel and sand substrates (West et al. 2000, p.
253). Sheepnose typically occur in shallow shoal habitats with moderate
to swift currents--ranging from riffles of a few inches in depth to
runs that exceed 20 feet (6 meters) in larger rivers--over mixtures of
coarse sand, gravel, and clay (Ortman 1919, p. 68; Cummings and Mayer
1992, p. 50; Oesch 1995, p. 121; Parmalee and Bogan 1998, pp. 77, 177;
Jones et al. 2019, p. 205). Snuffbox typically occur in swift currents
of riffles and shoals in rivers and streams and the wave-washed shores
of lakes over gravel and sand with occasional cobble and boulders
(Cummings and Mayer 1992, p. 162; Parmalee and Bogan 1998, p. 108).
Spectaclecase typically occur in rivers and streams with slow to swift
currents--often in quiet water near the interface of swift currents--
over substrates that range from mud and sand to gravel, cobble, and
boulders within relatively shallow riffles and shoals (Stansbery 1967,
pp. 29-30; Buchanan 1980, p. 13; Parmalee and Bogan 1998, p. 50; Baird
2000, pp. 5-6).
Appropriate flow is critical for delivering oxygen and nutrients
for respiration and filtration (i.e., survival and growth), essential
for reproduction to allow glochidia to move to their host and encyst,
as well as removing silt and other fine sediments from within rock
structures and crevices, which prevents mussel suffocation and
degradation of mussel and host-fish shelter habitats. Normal
fluctuations in flow velocity are expected; however, extreme changes
can be detrimental. Significant or prolonged increases in velocity,
typically associated with flood conditions, have the potential to
dislodge and scour mussels and move the bed, destroying habitat for the
mussels and their host fishes (Holland-Bartels 1990, pp. 331-332;
Layzer and Madison 1995, p. 135). Further, abnormally high velocities
have the potential to cause glochidia mortality due to wash out and
displacement of juveniles and adults. Alternatively, extreme low flows,
typically associated with drought or water withdrawals, can impact
reproduction, feeding, respiration, and in some cases, result in
exposure and desiccation of the species (Fisher and LaVoy 1972, pp.
1473-1476; Stegman 2020, entire). Although some individuals are found
in areas that experience seasonal low flows, areas that experience
periodic drying or intermittent flow generally cannot support mussel
assemblages.
Appropriate water quality is critical to the survival,
reproduction, and persistence of all life stages of freshwater mussels.
Point and non-point source contaminants can result in water quality and
habitat degradation. Contaminants alter the chemical, physical, and
biological characteristics of a stream, resulting in lethal and sub-
lethal effects to mussels and their fish hosts. Although specific data
for these parameters with respect to these four species are not
directly available, mussels in general are similar in terms of
sensitivity to certain thresholds, depending on the life stage exposed.
In general, mussels need water temperatures below 86 degrees Fahrenheit
(30 degrees Celsius), dissolved oxygen concentrations greater than 5
milligrams per liter (Pandolfo 2010, entire), and water quality
concentrations below acute toxicity levels to mussels for contaminants
such as total ammonia, nitrogen, copper, chloride, and sulfate (see
Appendix B, Service 2022a, b, c, d).

Habitat Connectivity

A mussel population includes more than one mussel bed; it is the
collection of mussel beds within a stream reach between which infested
host fish may travel, allowing for ebbs and flows in mussel bed density
and abundance through time throughout the population's occupied reach.
Therefore, sufficiently resilient populations of all four species must
occupy connected stream reaches long enough so that stochastic events
that affect individual mussel beds do not eliminate the entire
population. Connectivity is characterized by suitable water quality,
lack of barriers to dispersal (e.g., perched culverts, hydropower dams
that lack passage for host fishes, water control structures), and
presence of suitable shelter habitat and forage base for host fish(es).
Repopulation, through dispersal via infected host fish from other
mussel beds within a given stream reach, can allow the population and
individual beds within that population to recover from these stochastic
events. Long stream reaches are more likely to support sufficiently
resilient populations into the future than shorter stream reaches;
thus, long reaches of connected stream habitat are essential to support
all life stages of all four species.

Presence of Host Fish Species

All four species are obligate parasites that rely on specific host-
fish for developing into juvenile mussels and dispersal. Glochidia must
come into contact with specific host fish to ensure survival; without
the proper host fish, glochidia will perish and fail to transform into
juvenile mussels. Each

[[Page 22599]]

mussel species relies on a different suite of host fish(es).
Rayed bean depend on darter and sculpin species as host fish;
however, the exact suite of host fish species is unknown (Parmalee and
Bogan, 1998, p. 245; West et al. 2000, p. 254). The only published
studies identify the Tippecanoe darter (Etheostoma tippecanoe) and
spotted darter (E. maculatum) as host fish (White et al. 1996, p. 191;
Gibson et al. 2011, p. 7); however, these species are not (and were
not) found throughout the species' current or historical range. Other
host fishes are thought to include the greenside darter (E.
blenniodes), rainbow darter (E. caeruleum), mottled sculpin (Cottus
bairdi), and largemouth bass (Micropterus salmoides) (Woolnough 2002,
p. 51). Based on closely related species that occur in the same areas
and habitats, additional hosts may include species in the subgenus
Nothonotus of Etheostoma, sculpins (Cottus spp.), and fantail darter
(E. flabellare) (Jones 2002, pers. comm.).
Sheepnose depend on mimic shiner (Notropis volucellus) and sauger
(Sander canadensis) as host fish; of these, only mimic shiner has been
observed to be naturally infested and successfully facilitate
transformation of juveniles in the lab and is most likely the primary
host species. However, lab studies suggest that sheepnose may be able
to use a wider variety of fish species including fathead minnow
(Pimephales promelas), creek chub (Semotilus atrromaculatus), central
stoneroller (Campostoma anomalum), brook stickleback (Culaea
inconstans), and golden shiner (Notemigonus cryoleucas) (Watters et al.
2005, pp. 11-12; Bradley 2021, pers. comm.).
Snuffbox mussels rely on darter and sculpin species as fish hosts,
using log perch (Percina caprodes) as their primary host species.
Female snuffbox lure host fish with an inflated mantle (i.e., lure) and
close their shell around the head of the fish long enough to expel
their glochidia and allow for their attachment to the gills of the
fish, before releasing the fish (Schwalb et al. 2011, p. 224). Given
this life history strategy, they rely on clear water that allows their
lures to be visible by potential fish hosts. Other potential host
species from lab studies include the blackside darter (P. maculata),
rainbow darter, Iowa darter (E. exile), blackspotted topminnow
(Fundulus olivaceous), mottled sculpin, banded sculpin (C. carolinae),
Ozark sculpin (C. hypselurus), largemouth bass, and brook stickleback
(Sherman 1994, p. 17, Yeager and Saylor 1995, p. 3; Hillegass and Hove
1997, p. 25; Barnhart et al. 1998, p. 34; Hove et al. 2000, p. 30;
Sherman Mulcrone 2004, pp. 100-103).
Spectaclecase depend on mooneye (Hiodon tergisus) and goldeye
(Hiodon alosoides) as host fishes (Sietman et al. 2017, p. 18). Natural
infestations of spectaclecase have been observed on bigeye chub
(Hybopsis amblops) and pealip redhorse (Moxostoma pisolabrum); however,
they are not confirmed host fish species because juvenile mussels have
not been observed transforming from these species in lab studies (Baird
2000, p. 24).

Summary of Essential Physical or Biological Features

We derive the specific physical or biological features essential to
the conservation of the rayed bean, sheepnose, snuffbox, and
spectaclecase from studies of the species' habitat, ecology, and life
history as described above. Additional information can be found in the
SSA report for each species (Service 2022a, pp. 3-10; Service 2022b,
pp. 4-13; Service 2022c, pp. 3-11; Service 2022d, pp. 4-11; all SSA
reports are available on <a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-
R3-ES-2024-0144) and on the Service's website at the respective
species' profile pages (see Availability of supporting materials under
ADDRESSES, above). The primary habitat features that support resiliency
of the four mussel species include flow regime, habitat connectivity,
water and sediment quality, and the presence of host fish species. The
link between these habitat features and the needs of each life stage of
the four mussel species is summarized in table 1, below.

Table 1--Habitat Requirements for Each Life Stage of the Four Mussel Species
----------------------------------------------------------------------------------------------------------------
Supporting habitat or biological
Life stage features Reference
----------------------------------------------------------------------------------------------------------------
Fertilized eggs....................... <bullet> Suitable water quality......... Ortman 1919, p. 66; Fuller
<bullet> Sexually mature males in 1974, pp. 240-241; Berg et
proximity to sexually mature females.. al. 2008, p. 397; Haag 2012,
<bullet> Suitable spawning water pp. 38-39.
temperatures..
<bullet> Suitable flow conditions.......
Glochidia............................. <bullet> Suitable water quality (clear Fuller 1974, pp. 240-241;
water for visual attraction of host). Strayer 2008, p. 65; Guenther
<bullet> Availability of host fish for et al. 2009, p. 20; Haag
attachment.. 2012, pp. 41-42; Wolf et al.
[cir] Rayed bean: darter and sculpin 2012, p. 7; Hove et al. 2015,
species.. pp. 4, 6-8, 12-13.
[cir] Sheepnose: mimic shiner (Notropis
volucellus) and sauger (Sander
canadensis)..
[cir] Snuffbox: logperch (Percina
caprodes) and darter and sculpin
species..
[cir] Spectaclecase: mooneye (Hiodon
tergisus) and goldeye (H. alosoides)..
<bullet> Suitable water temperature.....
<bullet> Suitable flow conditions to
ensure glochidia encounter host..

[[Page 22600]]

Juveniles............................. <bullet> Suitable water quality Ortman 1919, p. 68; Fuller
(appropriate interstitial chemistry, 1974, pp. 220-221, 238-246;
low salinity, low ammonia, low copper Cummings and Mayer 1992, p.
and other contaminants, high dissolved 50; Dimock and Wright 1993,
oxygen). pp. 188-190; Yeager et al.
<bullet> Suitable water temperature..... 1994, p. 221; Sparks and
<bullet> Suitable flow conditions....... Strayer 1998, p. 132;
<bullet> Host fish dispersal............ Augspurger et al. 2003, p.
<bullet> Food availability: smaller 2,574; Augspurger et al.
algae, detritus, bacteria, organic 2007, p. 2,025; Schwalb et
matter, pedal feeding for first several al. 2011, entire; Strayer and
months.. Malcom 2012, pp. 1,787-1,788;
<bullet> Suitable substrate conditions:. Watters et al. 2009, p. 221.
[cir] Rayed bean and snuffbox: stable
sand and gravel..
[cir] Sheepnose: firm/stable; coarse
sand and gravel; cobble; may include
mud..
[cir] Spectaclecase: firm/stable; coarse
sand, gravel, and rock free from
excessive silt; may include large slabs/
boulders..
Adults................................ <bullet> Suitable water quality Ortmann 1919, p. 68; Fuller
(appropriate interstitial chemistry, 1974, pp. 221, 240-246;
low salinity, low ammonia, low copper Cummings and Mayer 1992, p.
and other contaminants, high dissolved 50; Yeager et al. 1994, p.
oxygen). 221; Parmalee and Bogan 1998,
<bullet> Suitable water temperature..... p. 177; Nichols and Garling
<bullet> Suitable flow conditions....... 2000, p. 881; Chen et al.
<bullet> Food availability: algae, 2001, pp. 213-214; Spooner
detritus, bacteria, dissolved organic and Vaughn 2008, p. 308;
matter, microscopic animals.. Watters et al. 2009, p. 221.
<bullet> Suitable substrate conditions:.
[cir] Rayed bean and snuffbox: stable
sand and gravel..
[cir] Sheepnose: firm/stable; coarse
sand and gravel; cobble; may include
mud..
[cir] Spectaclecase: firm/stable; coarse
sand, gravel, and rock free from
excessive silt; may include large slabs/
boulders..
----------------------------------------------------------------------------------------------------------------

We have determined that the following physical or biological
features are essential to the conservation of the rayed bean,
sheepnose, snuffbox, and spectaclecase:
(i) Adequate flows, or a hydrological 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.
(ii) Suitable substrates and connected instream habitats,
characterized by geomorphologically stable stream channels and banks
(i.e., channels that maintain lateral dimensions, longitudinal
profiles, and sinuosity patterns over time without an aggrading or
degrading bed elevation) that support the four mussel species and their
respective host fishes. For rayed bean and snuffbox, suitable
substrates are stable gravel and sand with moderate flow and aquatic
vegetation in and adjacent to riffles and shoals. For sheepnose,
suitable substrates are firm or stable coarse sand, gravel, or rock
free from excessive silt. For spectaclecase, these substrates are firm
or stable substrates of coarse sand and gravel, are free from excessive
silt, and typically include large rock, slabs, or boulders.
(iii) Water and sediment quality necessary to sustain natural
physiological processes for normal behavior, growth, and viability of
all life stages, including appropriate levels of dissolved oxygen
(generally above 2 to 3 parts per million (ppm)), salinity (generally
below 2 to 4 ppm), and temperature (generally below 86 degrees
Fahrenheit ([deg]F) (30 degrees Celsius ([deg]C))). Additionally,
concentrations of contaminants, including (but not limited to) ammonia,
nitrate, copper, and chloride, are below acute toxicity levels for
mussels.
(iv) The presence and abundance of host fishes necessary for
recruitment of the species. For the rayed bean, these are darter and
sculpin species; for the sheepnose, these are mimic shiner (Notropis
volucellus) and sauger (Sander canadensis); for the snuffbox, these are
logperch (Percina caprodes) and darter and sculpin species; and for the
spectaclecase, these are mooneye (Hiodon tergisus) and goldeye (H.
alosoides).

Special Management Considerations or Protection

When designating critical habitat, we assess whether there are
specific areas within the geographical area occupied by the species at
the time of listing containing physical or biological features which
(1) are essential to the conservation of the species, and (2) may
require special management considerations or protection.
The features essential to the conservation of the rayed bean,
sheepnose, snuffbox, and spectaclecase may require special management
considerations or protection to reduce the following threats: (1)
construction or operation of reservoirs; (2) urbanization of the
landscape, including (but not limited to) land conversion to impervious
surfaces for urban and commercial use, infrastructure (pipelines,
roads, bridges, utilities), and wastewater treatment; (3) significant
alteration of water quality and nutrient pollution from a variety of
activities, such as mining and agricultural activities; (4) land-use
activities that remove large areas of forested wetlands and riparian
systems; (5) culvert, dam, and pipe installation that creates barriers
to movement for the mussels or their host fish; and (6) 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, implementation of best management practices
(for silvicultural and agricultural land uses) designed to reduce
sedimentation, erosion, and bank destruction; implementation of habitat
restoration projects; protection of riparian corridors and woody
vegetation; and modification of dam operations or dam removal or both
to more closely match natural flow regimes; improved stormwater
management; and reduction of other watershed and floodplain
disturbances that release sediments, pollutants, or nutrients into the
water.

[[Page 22601]]

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 species because we have
not identified any unoccupied areas that meet the definition of
critical habitat, and we have determined that occupied areas are
sufficient to conserve these four species. Within the recovery plans
for all four species, we outline that recovery can be achieved by
protecting and maintaining or enhancing existing occupied areas, with
no need to create or establish new habitat areas or populations for all
four species. Thus, the designation includes only the occupied rivers
and streams within the species' ranges that contain the physical or
biological features essential to the conservation of the species and
that provide the best conditions for the maintenance and expansion of
existing populations.

Methodology Used for Selection of Critical Habitat Units

First, we identified those areas within the geographical areas
occupied by the species at the time of listing that contain the
essential physical or biological features and determined which of these
features may require special management considerations or protection.
Across all species, we included the areas where the high-condition
populations--defined in the SSA report as populations with stable to
increasing demography and known evidence of recent recruitment thus
indicating a high estimated probability of persistence--occur because
these are the areas that contain the features that currently meet the
four species' needs for maintaining viability. The presence of the
essential physical or biological features in these areas result in
populations that have recruitment, varied age class structures, and
high-density populations that are important to conservation and
recovery actions, as they may serve to bolster other diminished or
extirpated populations.
Second, we examined the overall contribution of moderate-condition
populations--defined in the SSA report as populations with stable to
slightly decreasing demography with limited evidence of recruitment,
thus indicating a moderate probability of persistence--to viability of
the species, as well as the level of threats acting on those
populations. We then considered adjacency and connectivity of these
moderate-condition populations to the high-condition and other
moderate-condition populations and included moderate-condition areas on
a case-by-case basis. We did not include populations that have
potentially low likelihood of recovery due to limited abundances,
currently have high levels of threats acting on the species and its
habitat, or lack of connectivity to other high- or moderate-condition
populations. We did not include areas that do not contain the essential
physical or biological features.
Third, we evaluated spatial redundancy and representation across
each of the four species' ranges to identify any remaining,
consistently observable populations in a major river basin that may
contain unique diversity or habitat or both. If we identified such
populations, we included them in this final critical habitat
designation. For instance, the lower Mississippi River Basin is
comprised of a single population of sheepnose within the Big Sunflower
River of Bolivar and Sunflower Counties, Mississippi; this population
is in low condition. However, this population exists at the southern
edge of the species' range and may have unique genetic diversity that
is not present elsewhere within the species' range, and this unit
contains one or more of the essential physical or biological features.
Thus, we include this stream segment in the sheepnose's final critical
habitat designation to enhance the likelihood of maintaining genetic
diversity.
Finally, we evaluated the overlap of the four species' occurrences,
as well as their overlap with other listed aquatic species and
designated critical habitat, where existing conservation and monitoring
efforts may be ongoing. In areas with a high degree of overlap or
existing conservation efforts, we included areas of critical habitat
within the overlapping areas. These areas were considered in
formulating this final critical habitat designation because they
contain the physical or biological features that are essential to the
conservation of the species and that may require special management
considerations. These areas may promote conservation and recovery
through maintaining the ecological community and existing genetic
diversity for the species.
For all critical habitat units, we define the upstream and
downstream boundaries around areas that were occupied by the species at
the time of listing and that contain the physical or biological
features essential to the conservation of the species using easily
recognizable features (e.g., confluence of two named streams,
impoundments).
Sources of data for these final critical habitat designations
include multiple databases maintained by universities, information from
State agencies throughout the species' ranges, and numerous survey
reports on threats throughout the species' ranges (as cited in Service
2022a, entire; Service 2022b, entire; Service 2022c, entire; Service
2022d, entire; all reports are available on <a href="https://www.regulations.gov">https://www.regulations.gov</a>
at Docket No. FWS-R3-ES-2024-0144). We also reviewed available
information that pertains to the habitat requirements for 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 (as cited
in Service 2022a, entire; Service 2022b, entire; Service 2022c, entire;
Service 2022d, entire; all reports are available on <a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-R3-ES-2024-0144). River segments
were defined using the National Hydrography Dataset Plus High
Resolution (NHDPlus HR) dataset maintained by the U.S. Geological
Survey (Moore et al. 2019, entire).
In summary, for areas within the geographical area occupied by the
species at the time of listing, we delineated critical habitat unit
boundaries using the following criteria:
(1) We identified river and stream reaches with observations from
2000 to present for rayed bean, sheepnose, and snuffbox, as well as
river and stream reaches with observations from 1970 to present for
spectaclecase, and considered these areas to be currently occupied. For
spectaclecase, we determined that it is reasonable to find these areas
occupied over a longer timeframe due to its longer lifespan (50 or more
years on average), compared to the other mussel species (less than 30
years on average). For all species, the available State heritage
databases and information, as well as increased survey efforts and
detections of the species since 2012 in previously unknown areas of
suitable habitat, support the likelihood of the species' continued
presence in known occupied areas since the time of listing in 2012.

[[Page 22602]]

(2) We delineated specific habitat areas based on Natural Heritage
Element Occurrences, published reports, and unpublished survey data
provided by States and other partners. These areas provide habitat for
the four mussel species, despite fluctuations in local conditions. The
areas within the proposed units represent continuous river and stream
reaches of relatively free-flowing habitat patches capable of
sustaining fish hosts and allowing for transport of glochidia, which
are essential for reproduction and dispersal of these species.
(a) Rayed bean: We are designating critical habitat for the rayed
bean in the Black River, Pine River, Belle River, River Raisin, Clinton
River, Fish Creek, Swan Creek, Blanchard River, Allegheny River, Olean
Creek, Oil Creek, Oswayo Creek, French Creek, LeBoeuf Creek, Muddy
Creek, Cussewago Creek, Little Darby Creek, Big Darby Creek, Great
Miami River, and Tippecanoe River (see Final Critical Habitat
Designation, below). All of these rivers and streams were known to be
occupied at the time of listing except River Raisin, Oil Creek, Oswayo
Creek, and Little Darby Creek. Although the rayed bean was not known
from River Raisin (detected in 2015), Oil Creek (detected in 2015),
Oswayo Creek (detected in 2015), and Little Darby Creek (detected in
2023) at the time of listing, all of the rivers and streams are either
tributaries to or occur within a watershed where the rayed bean was
known to occur at the time of listing, except for River Raisin. Eight
adult rayed bean were detected in the River Raisin in 2015,
representing an occurrence in an entirely new watershed that was not
known to be occupied at the time of listing. Given that the species is
able to live in excess of 20 years, juvenile and adult mussels are
immobile, adults mature around age 4 or 5, and the detections were of
reproducing adults of unknown ages, it is reasonable to assume that
these watersheds were also occupied at the time of listing in 2012 and
had not been detected due to lack of survey effort. Thus, we consider
all units to have been occupied at the time of listing and appropriate
for designation as occupied critical habitat. Furthermore, given that
the mussel beds within River Raisin, Oil Creek, Oswayo Creek, and
Little Darby Creek are considered currently occupied and fall within
the currently extant range for the species (i.e., wherever found), we
would consult on any activities that are occurring or that will occur
within these areas of the species' range.
(b) Sheepnose: We are designating critical habitat for the
sheepnose in the Chippewa River, Kankakee River, Meramec and Bourbeuse
Rivers, Allegheny River, Green River, Tippecanoe River, Walhonding
River, Tennessee River, Clinch River, Powell River, and Big Sunflower
River (see Final Critical Habitat Designation, below). All of these
rivers and streams were known to be occupied at the time of listing.
(c) Snuffbox: We are designating critical habitat for the snuffbox
in the Wolf River, Embarrass River, Little Wolf River, Grand River
(Michigan), Flat River, Clinton River, Huron River, Grand River (Ohio),
West Branch Grand River (Ohio), Allegheny River, French Creek, LeBoeuf
Creek, Cussewago Creek, Woodcock Creek, Muddy Creek, Conneaut Outlet,
West Fork River, Shenango River, Little Shenango River, Middle Island
Creek, Meathouse Fork, McElroy Creek, Little Kanawha River, Leading
Creek, Hughes River, North Fork Hughes River, South Fork Hughes River,
Kanawha River, Elk River (West Virginia), Olentangy River, Little Darby
Creek, Big Darby Creek, Stillwater River, Tygarts Creek, Kinniconick
Creek, Licking River, Slate Creek, Middle Fork Kentucky River, Red Bird
River, Red River, Green River, Salamonie River, Tippecanoe River,
Embarras River, Rolling Fork Salt River, Clinch River, Powell River,
Paint Rock River, Elk River (Tennessee), Duck River, St. Croix River,
Meramec River, Bourbeuse River, St. Francis River, and Spring River
(see Final Critical Habitat Designation, below). All of these rivers
and streams were known to be occupied at the time of listing except for
Cussewago Creek, West Fork River, Meathouse Fork, South Fork Hughes
River, Leading Creek, and Kanawha River. Although the snuffbox was not
reported from or detected in Cussewago Creek (detected in 2011;
reported post-listing), West Fork River (detected in 2020), Meathouse
Fork (detected in 2001; reported in 2016), South Fork Hughes River
(detected in 2001; reported in 2016), Leading Creek (detected in 2017),
and Kanawha River (detected in 2017) prior to the snuffbox's listing in
2012, all of the rivers and streams are either tributaries to or occur
within the watershed where the snuffbox was known to occur at the time
of listing. In Cussewago Creek, a fresh dead adult was detected in
2011, but this observation was not reported to the Service until after
the species was listed. In West Fork River, three live adults were
found in 2020. In the Meathouse Fork and South Fork Hughes River, live
snuffbox were detected in 2001, but the data were not reported to the
Service until 2016. Follow up surveys in the South Fork Hughes River in
2017 found live individuals dispersed across 24 miles (39 kilometers)
of river. In Leading Creek, although the species was presumed
extirpated from this reach at the time of listing, one live individual
was detected in 2017. Finally, in the Kanawha River, although the
species was thought to be extirpated from this reach at the time of
listing, one live individual was detected in 2017. Regarding the
Cussewago Creek, Meathouse Fork, and South Fork Hughes River, snuffbox
was extant in these areas at the time of listing in 2012; however,
these data were not provided to the Service until after the species was
listed. Regarding all rivers--including the West Fork River, Leading
Creek, and Kanawha River--given that all mussel beds occur within areas
that are connected to known occupied areas, the species is known to
live in excess of 20 years, juvenile and adult mussels are immobile,
adults mature around age 5, and many of these detections were of
reproducing adults, it is reasonable to assume that these areas were
occupied at the time the species was listed in 2012. As such, we
consider all units to be occupied at the time of listing and
appropriate for designation as occupied critical habitat. Furthermore,
given that the mussel beds within Cussewago Creek, West Fork River,
Meathouse Fork, South Fork Hughes River, Leading Creek, and Kanawha
River are considered to be currently occupied and fall within the
currently extant range for the species (i.e., wherever found), we would
consult on any activities that are occurring or that will occur within
these areas of the species' range.
(d) Spectaclecase: We are designating critical habitat for the
spectaclecase in the St. Croix River, Mississippi River, Meramec River,
Big River, Gasconade River, Big Piney River, Ouachita River, Tennessee
River, Clinch River, Nolichucky River, Green River, and Kanawha River
(see Final Critical Habitat Designation, below). All of these rivers
and streams were known to be occupied at the time of listing.
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 rayed bean, sheepnose, snuffbox,
and spectaclecase. Critical habitat for these mussels includes only
stream channels up to bankfull height, where the stream base flow is
contained within the channel. The scale of the maps we prepared under
the parameters

[[Page 22603]]

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
(and not affecting the designated critical habitat) will not trigger
section 7 consultation 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.
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 preamble of this document. We will make the coordinates or plot
points or both on which each map is based available to the public on
<a href="https://www.regulations.gov">https://www.regulations.gov</a> at Docket No. FWS-R3-ES-2024-0144.

Final Critical Habitat Designation

We are designating approximately 599 river miles (rmi) (964 river
kilometers (rkm)) in 15 units as critical habitat for rayed bean;
approximately 801 rmi (1,289 rkm) in 11 units as critical habitat for
sheepnose; approximately 2,425 rmi (3,902 rkm) in 38 units as critical
habitat for snuffbox; and approximately 1,140 rmi (1,835 rkm) in 12
units as critical habitat for spectaclecase. In total, we are
designating approximately 3,814 unique rmi (6,138 rkm) of critical
habitat within 76 units across 17 States; many units overlap entirely
or within some portion of the designated units for the mussel species
that are the subject of this final rule. All units are considered to be
occupied by the species--which are already listed as endangered species
under the Act. No unoccupied units are being designated for any of the
four species. All critical habitat units consist of the streambed up to
the ordinary high-water mark, as defined at 33 CFR 328.3(c)(4) in the
regulations that implement the Clean Water Act (33 U.S.C. 1251 et
seq.). Streambed ownership varies by State and by navigability of the
stream. In general, the streambed up to the ordinary high-water mark is
public waters of the State; however, there are instances where the
streambed is owned by the adjacent landowners. When describing land
ownership, below, we use adjacent landownership as a proxy for
streambed ownership that is consistent across the ranges of these
species. The critical habitat areas we describe below constitute our
current best assessment of areas that meet the definition of critical
habitat for all four species.
The 15 areas we designate as critical habitat for the rayed bean
are: (1) Black River, (2) Pine River, (3) Belle River, (4) River
Raisin, (5) Clinton River, (6) Fish Creek, (7) Swan Creek, (8)
Blanchard River, (9) Allegheny River, (10) Middle Allegheny River, (11)
French Creek, (12) Little Darby Creek, (13) Big Darby Creek, (14) Great
Miami River, and (15) Tippecanoe River. Table 2 shows the critical
habitat units, identifies the owners by type (Federal, State, local, or
private) of land adjacent to each unit, and provides the approximate
area of each unit. We use the four-letter species code for rayed bean
(RABE) to name its critical habitat units. All units are considered
occupied at the time of listing.

Table 2--Critical Habitat Units for Rayed Bean
[Length estimates reflect all land within critical habitat unit boundaries.]
----------------------------------------------------------------------------------------------------------------
Size of unit in river
Critical habitat unit or subunit name Adjacent land ownership type miles (river
kilometers)
----------------------------------------------------------------------------------------------------------------
RABE 1: Black River............................. State................................ 7 (11)
Private.............................. 25 (40)
Total................................ 32 (51)
RABE 2: Pine River.............................. Private.............................. 3 (5)
Total................................ 3 (5)
RABE 3: Belle River............................. Private.............................. 8 (13)
Total................................ 8 (13)
RABE 4: River Raisin............................ Local................................ 0.3 (0.5)
Private.............................. 8 (13)
Total................................ 8 (13)
RABE 5: Clinton River........................... Local................................ 1 (2)
Private.............................. 7 (11)
Total................................ 8 (13)
RABE 6: Fish Creek.............................. State................................ 1 (2)
Private.............................. 30 (48)
Total................................ 31 (50)
RABE 7: Swan Creek.............................. Private.............................. 4 (7)
Total................................ 4 (7)
RABE 8: Blanchard River......................... Local................................ 1 (2)
Private.............................. 27 (43)
Total................................ 28 (45)
RABE 9: Allegheny River......................... State................................ 12 (19)
Shared: State & Local *.............. 0.1 (0.2)
Local................................ 2 (3)
Private.............................. 68 (109)
Total................................ 82 (131)
RABE 10: Middle Allegheny River................. Federal.............................. 23 (37)
Shared: Federal & State *............ 3 (5)
State................................ 13 (21)
Local................................ 4 (6)
Private.............................. 133 (209)
Total................................ 176 (283)

[[Page 22604]]

RABE 11: French Creek........................... Federal.............................. 13 (21)
State................................ 3 (5)
Local................................ 1 (2)
Private.............................. 83 (134)
Total................................ 100 (161)
RABE 12: Little Darby Creek..................... State................................ 4 (7)
Private.............................. 17 (28)
Total................................ 21 (35)
RABE 13: Big Darby Creek........................ State................................ 1 (2)
Local................................ 13 (21)
Private.............................. 24 (39)
Total................................ 38 (61)
RABE 14: Great Miami River...................... Private.............................. 11 (18)
Total................................ 11 (18)
RABE 15a: Tippecanoe River...................... Local................................ 1 (2)
Private.............................. 27 (43)
Total................................ 28 (45)
RABE 15b: Tippecanoe River...................... State................................ 2 (3)
Private.............................. 17 (27)
Total................................ 19 (31)
---------------------------------------------------------------
Total by Ownership Type......................... Federal.............................. 36 (58)
Shared: Federal & State *............ 3 (5)
State................................ 43 (69)
Shared: State & Local *.............. 0.1 (0.2)
Local................................ 24 (39)
Private.............................. 493 (793)
Total................................ 599 (964)
----------------------------------------------------------------------------------------------------------------
* Shared ownership corresponds to stream segments with different public ownership on opposite sides of the
river.
Note: Lengths may not sum due to rounding.

The 11 areas we designate as critical habitat for the sheepnose
are: (1) Lower Chippewa River, (2) Kankakee River, (3) Meramec and
Bourbeuse Rivers, (4) Middle Allegheny-Tionesta, (5) Upper Green River,
(6) Tippecanoe River, (7) Walhonding River, (8) Lower Tennessee River,
(9) Upper Clinch River, (10) Powell River, and (11) Big Sunflower
River. Table 3 shows the critical habitat units, identifies the owners
by type (Federal, State, local, or private) of land adjacent to each
unit, and provides the approximate area of each unit. We use the four-
letter species code for sheepnose (SHNO) to name its critical habitat
units. All units are considered occupied at the time of listing.

Table 3--Critical Habitat Units for Sheepnose
[Length estimates reflect all land within critical habitat unit boundaries.]
----------------------------------------------------------------------------------------------------------------
Size of unit in river
Critical habitat unit name Adjacent land ownership type(s) miles (river
kilometers)
----------------------------------------------------------------------------------------------------------------
SHNO 1: Lower Chippewa River.................... Federal.............................. 5 (8)
Shared: Federal & State *............ 1 (2)
State................................ 29 (47)
Local................................ 1 (2)
Private.............................. 21 (34)
Total................................ 57 (92)
SHNO 2: Kankakee River.......................... State................................ 18 (29)
Local................................ 10 (16)
Private.............................. 23 (37)
Total................................ 51 (82)
SHNO 3: Meramec and Bourbeuse Rivers............ State................................ 18 (29)
Local................................ 18 (29)
Private.............................. 117 (188)
Total................................ 153 (246)
SHNO 4: Middle Allegheny-Tionesta............... State................................ 0.04 (0.06)
Private.............................. 28 (45)
Total................................ 28 (45)
SHNO 5: Upper Green River....................... Federal.............................. 27 (43)
State................................ 7 (11)
Local................................ 1 (2)
Private.............................. 122 (196)
Total................................ 157 (253)

[[Page 22605]]

SHNO 6: Tippecanoe River........................ State................................ 9 (14)
Private.............................. 75 (121)
Total................................ 84 (135)
SHNO 7: Walhonding River........................ State................................ 0.5 (0.8)
Local................................ 1 (2)
Private.............................. 22 (35)
Total................................ 24 (38)
SHNO 8: Lower Tennessee River................... Local................................ 0.4 (0.6)
Private.............................. 22 (35)
Total................................ 23 (36)
SHNO 9: Upper Clinch River...................... Federal.............................. 0.3 (0.5)
State................................ 6 (10)
Private.............................. 100 (161)
Total................................ 106 (171)
SHNO 10: Powell River........................... State................................ 0.3 (0.5)
Private.............................. 62 (100)
Total................................ 63 (101)
SHNO 11: Big Sunflower River.................... Federal.............................. 0.5 (0.8)
State................................ 2 (3)
Private.............................. 53 (86)
Total................................ 56 (90)
---------------------------------------------------------------
Total by Land Ownership Type................ Federal.............................. 33 (53)
Shared: Federal & State *............ 1 (2)
State................................ 89 (143)
Local................................ 31 (50)
Private.............................. 647 (1,041)
Total................................ 801 (1,289)
----------------------------------------------------------------------------------------------------------------
* Shared ownership corresponds to stream segments with different public ownership on opposite sides of the
river.
Note: Lengths may not sum due to rounding.

The 38 areas we designate as critical habitat for the snuffbox are:
(1) Wolf River, (2) Embarrass River, (3) Little Wolf River, (4) Grand
River (Michigan), (5) Clinton River, (6) Huron River, (7) Grand River
(Ohio), (8) Allegheny River, (9) French Creek, (10) West Fork River,
(11) Shenango River, (12) Middle Island Creek, (13) Little Kanawha
River, (14) Kanawha River, (15) Olentangy River, (16) Little Darby
Creek, (17) Big Darby Creek, (18) Stillwater River, (19) Tygarts Creek,
(20) Kinniconick Creek, (21) Licking River, (22) Middle Fork Kentucky
River, (23) Red Bird River, (24) Red River, (25) Green River, (26)
Salamonie River, (27) Tippecanoe River, (28) Embarras River, (29)
Rolling Fork Salt River, (30) Clinch River, (31) Powell River, (32)
Paint Rock River, (33) Elk River, (34) Duck River, (35) St. Croix
River, (36) Meramec River, (37) St. Francis River, and (38) Spring
River. Table 4 shows the critical habitat units, identifies the owners
by type (Federal, State, local, or private) of land adjacent to each
unit, and provides the approximate area of each unit. We use the four-
letter species code for snuffbox (SNBO) to name its critical habitat
units. All units are considered occupied at the time of listing.

Table 4--Critical Habitat Units for Snuffbox Mussel
[Length estimates reflect all land within critical habitat unit boundaries.]
----------------------------------------------------------------------------------------------------------------
Size of unit in river
Critical habitat unit or subunit name Adjacent land ownership type(s) miles (river
kilometers)
----------------------------------------------------------------------------------------------------------------
SNBO 1: Wolf River.............................. Federal.............................. 0.2 (0.3)
State................................ 0.7 (1)
Local................................ 0.4 (0.7)
Private.............................. 7 (11)
Total................................ 8 (13)
SNBO 2a: Embarrass River........................ Private.............................. 11 (18)
Total................................ 11 (18)
SNBO 2b: Embarrass River........................ Private.............................. 7 (11)
Total................................ 7 (11)
SNBO 3: Little Wolf River....................... Private.............................. 12 (19)
Total................................ 12 (19)
SNBO 4: Grand River (Michigan).................. State................................ 9 (14)
Local................................ 5 (8)
Private.............................. 27 (43)
Total................................ 41 (65)

[[Page 22606]]

SNBO 5: Clinton River........................... Local................................ 0.9 (1)
Private.............................. 7 (12)
Total................................ 8 (13)
SNBO 6: Huron River............................. State................................ 7 (11)
Local................................ 2 (3)
Private.............................. 7 (12)
Total................................ 16 (26)
SNBO 7: Grand River (Ohio)...................... Local................................ 8 (12)
Private.............................. 16 (25)
Total................................ 23 (37)
SNBO 8: Allegheny River......................... State................................ 6 (10)
Local................................ 0.2 (0.3)
Private.............................. 29 (46)
Total................................ 35 (57)
SNBO 9a: French Creek........................... State................................ 0.7 (1)
Private.............................. 18 (29)
Total................................ 19 (30)
SNBO 9b: French Creek........................... Federal.............................. 13 (21)
State................................ 14 (23)
Local................................ 3 (4)
Private.............................. 81 (131)
Total................................ 111 (179)
SNBO 10: West Fork River........................ Private.............................. 22 (35)
Total................................ 22 (35)
SNBO 11: Shenango River......................... State................................ 0.7 (1)
Local................................ 0.5 (0.8)
Private.............................. 26 (42)
Total................................ 28 (44)
SNBO 12: Middle Island Creek.................... State................................ 0.1 (0.2)
Local................................ 2 (3)
Private.............................. 85 (137)
Total................................ 87 (140)
SNBO 13: Little Kanawha River................... Federal.............................. 0.5 (0.7)
State................................ 17 (27)
Local................................ 0.1 (0.2)
Private.............................. 183 (294)
Total................................ 200 (322)
SNBO 14: Kanawha River.......................... State................................ 2 (3)
Local................................ 2 (3)
Private.............................. 54 (87)
Total................................ 58 (93)
SNBO 15: Olentangy River........................ State................................ 0.3 (0.4)
Private.............................. 30 (48)
Total................................ 30 (48)
SNBO 16: Little Darby Creek..................... State................................ 4 (6)
Local................................ 0.004 (0.006)
Private.............................. 24 (39)
Total................................ 28 (45)
SNBO 17: Big Darby Creek........................ State................................ 0.6 (0.9)
Local................................ 20 (32)
Private.............................. 49 (78)
Total................................ 69 (111)
SNBO 18: Stillwater River....................... Local................................ 0.6 (1)
Private.............................. 11 (18)
Total................................ 12 (19)
SNBO 19: Tygarts Creek.......................... State................................ 1 (2)
Private.............................. 88 (141)
Total................................ 89 (143)
SNBO 20: Kinniconick Creek...................... Private.............................. 52 (84)
Total................................ 52 (84)
SNBO 21: Licking River.......................... State................................ 15 (24)
Local................................ 3 (5)
Private.............................. 221 (355)
Total................................ 239 (385)
SNBO 22: Middle Fork Kentucky River............. Private.............................. 13 (21)
Total................................ 13 (21)
SNBO 23: Red Bird River......................... Federal.............................. 3 (5)
Private.............................. 57 (92)
Total................................ 60 (97)

[[Page 22607]]

SNBO 24: Red River.............................. Federal.............................. 17 (28)
Shared: Federal & State *............ 0.8 (1)
State................................ 0.5 (0.8)
Private.............................. 12 (19)
Total................................ 31 (49)
SNBO 25: Green River............................ Federal.............................. 27 (43)
State................................ 7 (11)
Local................................ 2 (4)
Private.............................. 121 (195)
Total................................ 157 (253)
SNBO 26: Salamonie River........................ Federal.............................. 9 (15)
Private.............................. 3 (5)
Total................................ 12 (19)
SNBO 27a: Tippecanoe River...................... Local................................ 1 (2)
Private.............................. 27 (43)
Total................................ 28 (45)
SNBO 27b: Tippecanoe River...................... State................................ 2 (3)
Private.............................. 17 (27)
Total................................ 19 (31)
SNBO 28: Embarras River......................... State................................ 5 (8)
Local................................ 3 (5)
Private.............................. 63 (101)
Total................................ 71 (114)
SNBO 29: Rolling Fork Salt River................ Private.............................. 95 (153)
Total................................ 95 (153)
SNBO 30: Clinch River........................... Federal.............................. 0.3 (0.5)
State................................ 9 (15)
Local................................ 0.4 (0.6)
Private.............................. 160 (257)
Total................................ 170 (273)
SNBO 31: Powell River........................... State................................ 0.3 (0.5)
Private.............................. 66 (106)
Total................................ 66 (106)
SNBO 32: Paint Rock River....................... Shared: Federal & State *............ 0.3 (0.5)
State................................ 49 (80)
Private.............................. 3 (6)
Total................................ 53 (85)
SNBO 33: Elk River.............................. Private.............................. 27 (43)
Total................................ 27 (43)
SNBO 34: Duck River............................. State................................ 27 (43)
Local................................ 0.4 (0.6)
Private.............................. 20 (32)
Total................................ 47 (76)
SNBO 35: St. Croix River........................ Federal.............................. 19 (31)
Shared: Federal & State *............ 4 (6)
State................................ 8 (13)
Local................................ 0.1 (0.2)
Private.............................. 22 (35)
Total................................ 53 (85)
SNBO 36: Meramec River.......................... State................................ 23 (37)
Shared: State & Local *.............. 0.05 (0.09)
Local................................ 4 (6)
Private.............................. 200 (321)
Total................................ 227 (365)
SNBO 37: St. Francis River...................... Federal.............................. 0.05 (0.08)
State................................ 5 (8)
Private.............................. 53 (85)
Total................................ 58 (93)
SNBO 38: Spring River........................... State................................ 1 (2)
Private.............................. 32 (51)
Total................................ 33 (53)
------------------------

[[Page 22608]]

Total by Ownership Type..................... Federal.............................. 89 (143)
Shared: Federal & State *............ 5 (8)
State................................ 221 (356)
Shared: State & Local *.............. 0.05 (0.08)
Local................................ 54 (87)
Private.............................. 2,056 (3,309)
Total................................ 2,425 (3,902)
----------------------------------------------------------------------------------------------------------------
* Shared ownership corresponds to stream segments with different public ownership on opposite sides of the
river.
Note: Lengths may not sum due to rounding.

The 12 areas we designate as critical habitat for the spectaclecase
are: (1) St. Croix River, (2) Mississippi River, (3) Meramec River, (4)
Big River, (5) Gasconade River, (6) Big Piney River, (7) Ouachita
River, (8) Tennessee River, (9) Clinch River, (10) Nolichucky River,
(11) Green River, and (12) Kanawha River. Table 5, below, shows the
critical habitat units, identifies the owners by type (Federal, State,
local, or private) of land adjacent to each unit, and provides the
approximate area of each unit. We use the four-letter species code for
spectaclecase (SPCA) to name its critical habitat units. All units are
considered occupied at the time of listing.

Table 5--Critical Habitat Units for Spectaclecase
[Length estimates reflect all land within critical habitat unit boundaries.]
----------------------------------------------------------------------------------------------------------------
Size of unit in river
Critical habitat unit or subunit name Adjacent land ownership types miles (river
kilometers)
----------------------------------------------------------------------------------------------------------------
SPCA 1: Saint Croix............................. Federal.............................. 19 (31)
Shared: Federal & State *............ 3 (5)
State................................ 9 (14)
Local................................ 1 (2)
Private.............................. 21 (34)
Total................................ 53 (86)
SPCA 2: Mississippi River....................... Federal.............................. 28 (45)
Shared: Federal & State *............ 6 (10)
Shared: Federal & Local *............ 0.4 (0.6)
State................................ 5 (8)
Shared: State & Local *.............. 0.2 (0.3)
Local................................ 11 (18)
Private.............................. 82 (132)
Total................................ 132 (212)
SPCA 3: Meramec River........................... State................................ 29 (47)
Shared: State & Local *.............. 0.5 (0.8)
Local................................ 17 (27)
Private.............................. 110 (177)
Total................................ 156 (251)
SPCA 4: Big River............................... Local................................ 1 (2)
Private.............................. 10 (16)
Total................................ 11 (18)
SPCA 5: Gasconade River......................... Federal.............................. 9 (14)
State................................ 3 (5)
Private.............................. 211 (340)
Total................................ 223 (359)
SPCA 6a: Big Piney River........................ Federal.............................. 17 (27)
Shared: Federal & State *............ 0.5 (0.8)
State................................ 0.5 (0.8)
Private.............................. 16 (26)
Total................................ 34 (55)
SPCA 6b: Big Piney River........................ Federal.............................. 14 (23)
Private.............................. 5 (8)
Total................................ 19 (31)
SPCA 7: Ouachita River.......................... Local................................ 1 (2)
Private.............................. 82 (132)
Total................................ 83 (134)
SPCA 8: Tennessee River......................... Federal.............................. 0.3 (0.5)
Shared: Federal & State *............ 20 (32)
State................................ 112 (180)
Shared: State & Local *.............. 2 (3)
Local................................ 0.5 (0.8)
Private.............................. 7 (11)
Total................................ 142 (229)

[[Page 22609]]

SPCA 9: Clinch River............................ State................................ 9 (15)
Private.............................. 148 (238)
Total................................ 157 (253)
SPCA 10: Nolichucky River....................... State................................ 2 (4)
Private.............................. 35 (56)
Total................................ 37 (60)
SPCA 11: Green River............................ Federal.............................. 26 (42)
State................................ 5 (8)
Private.............................. 46 (74)
Total................................ 77 (124)
SPCA 12: Kanawha River.......................... Local................................ 0.4 (0.6)
Private.............................. 15 (24)
Total................................ 16 (25)
------------------------
Total by Ownership Type..................... Federal.............................. 114 (183)
Shared: Federal & State *............ 31 (50)
Shared: Federal & Local *............ 0.4 (0.6)
State................................ 174 (280)
Shared: State & Local *.............. 3 (5)
Local................................ 31 (50)
Private.............................. 787 (1,267)
Total................................ 1,140 (1,835)
----------------------------------------------------------------------------------------------------------------
* Shared ownership corresponds to stream segments with different public ownership on opposite sides of the
river.
Note: Lengths 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 rayed bean, sheepnose,
snuffbox, and spectaclecase mussels below.

I. Rayed Bean

All 15 units for rayed bean are considered occupied by the species
at the time of listing and contain all of the physical or biological
features essential to the species' conservation.
RABE 1: Black River
RABE 1 consists of approximately 32 rmi (51 rkm) of the Black River
and Mill Creek in St. Clair County, Michigan. The Black River portion
of the unit includes 8 rmi (13 rkm) in St. Clair County, Michigan, from
the State Highway 136 Bridge (Beard Road Bridge) in Clyde Township
downstream to the Wadhams Road Bridge in Kimball Township. This unit
also includes 24 rmi (38 rkm) of Mill Creek in St. Clair County,
Michigan, from its confluence with Thompson Drain northwest of Brockway
Township downstream to its confluence with Black River at Ruby in Clyde
Township, Michigan. The unit includes the river channel up to the
ordinary high-water mark.
Approximately 21.5 percent (7 rmi (11 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State)
ownership, and 78.5 percent (25 rmi (40 rkm)) are in private ownership.
Adjacent State lands are owned or managed by the Michigan Department of
Natural Resources. The unit partially overlaps with proposed critical
habitat for the proposed endangered salamander mussel (Simpsonaias
ambigua) (88 FR 57224, August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to the amount of impervious surface
and urbanization; and the presence of invasive species.
RABE 2: Pine River
RABE 2 consists of approximately 3 rmi (5 rkm) of the Pine River in
St. Clair County, Michigan. This unit extends from the confluence of
the Pine River and Rattle Run downstream to Newman Road in St. Clair
Township (St. Clair County, Michigan). The unit includes the river
channel up to the ordinary high-water mark.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to the amount of impervious surface
and urbanization; and the presence of invasive species.
RABE 3: Belle River
RABE 3 consists of approximately 8 rmi (13 rkm) of the Belle River
in St. Clair County, Michigan. This unit extends from the Westrick Road
Bridge downstream to the King Road Bridge in China Township, in St.
Clair County, Michigan. The unit includes the river channel up to the
ordinary high-water mark.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to the amount of impervious surface
and urbanization; and the presence of invasive species.
RABE 4: River Raisin
RABE 4 consists of approximately 8 rmi (13 rkm) of the River Raisin
in Lenawee County, Michigan. This unit extends from the Crockett
Highway Bridge in Palmyra Township downstream to the U.S. Route 223
Bridge (West Adrian Street) in the village of Blissfield, in Lenawee
County, Michigan. The unit includes the river channel up to the
ordinary high-water mark.
Approximately 3.2 percent (0.3 rmi (0.5 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 96.8

[[Page 22610]]

percent (8 rmi (13 rkm)) are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to the amount of impervious surface
and urbanization; and the presence of invasive species.
RABE 5: Clinton River
RABE 5 consists of approximately 8 rmi (13 rkm) of the Clinton
River in Oakland County, Michigan. This unit extends from downstream of
the fish hatchery at Waterford Township downstream to Cass Lake east of
the unincorporated community of Four Towns, in Oakland County,
Michigan. The unit includes the river channel up to the ordinary high-
water mark.
Approximately 11.0 percent (1 rmi (2 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 89.0 percent (7 rmi (11 rkm)) are in private ownership.
The unit fully overlaps with designated critical habitat for the
federally endangered snuffbox mussel and partially overlaps with
proposed critical habitat for the proposed endangered salamander mussel
(88 FR 57224; August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminant;
habitat degradation and loss due to the amount of impervious surface,
urbanization, and the lack of canopy cover and vegetative cover in the
riparian buffer; reduced connectivity due to barriers; and the presence
of invasive species.
RABE 6: Fish Creek
RABE 6 consists of approximately 31 rmi (50 rkm) of Fish Creek in
Steuben and DeKalb Counties, Indiana, and Williams County, Ohio. This
unit extends from the Ohio Turnpike Interstate 80/Interstate 90 Bridge
in Steuben County, Indiana, downstream to the confluence of Fish Creek
with St. Joseph River north of the village of Edgerton in Williams
County, Ohio. The unit includes the river channel up to the ordinary
high-water mark.
Approximately 3.3 percent (1 rmi (2 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State)
ownership, and 96.7 percent (30 rmi (48 rkm)) are in private ownership.
Adjacent State lands are owned or managed by the Ohio Department of
Natural Resources. The unit partially overlaps with designated critical
habitat for the federally threatened rabbitsfoot (Quadrula cylindrica
cylindrica) (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015) and
fully overlaps with proposed critical habitat for the proposed
endangered salamander mussel (88 FR 57224, August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
impacts to the hydrological regime; habitat degradation and loss due to
sedimentation and stream channelization; and the presence of invasive
species.
RABE 7: Swan Creek
RABE 7 consists of approximately 4 rmi (7 rkm) of Swan Creek in
Lucas County, Ohio. This unit extends from the Monclova Road Bridge in
the city of Maumee downstream to the Ohio Turnpike Interstate 80/
Interstate 90 Bridge in the city of Maumee, in Lucas County, Ohio. The
unit includes the river channel up to the ordinary high-water mark.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
impacts to the hydrological regime; habitat degradation and loss due to
the amount of impervious surface and urbanization; and the presence of
invasive species.
RABE 8: Blanchard River
RABE 8 consists of 28 rmi (45 rkm) of the Blanchard River in Hardin
and Hancock Counties, Ohio. This unit extends from the County Road 183
Bridge in Jackson Township (Hardin County, Ohio) downstream to the
State Route 568 Bridge (Carey Road Bridge) in the city of Findlay
(Hancock County, Ohio). The unit includes the river channel up to the
ordinary high-water mark.
Approximately 4.3 percent (1 rmi (2 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 95.7 percent (27 rmi (43 rkm)) are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to sedimentation and stream
channelization; and the presence of invasive species.
RABE 9: Allegheny River
RABE 9 consists of approximately 82 rmi (131 rkm) of the Allegheny
River, Honeoye Creek, Olean Creek, Oil Creek, and Oswayo Creek in
Allegany and Cattaraugus Counties, New York, and McKean and Potter
Counties, Pennsylvania. The Allegheny River portion of this unit
includes approximately 47 rmi (76 rkm) of the Allegheny River from its
confluence with Sartwell Creek near the unincorporated community of
Burtville in McKean County, Pennsylvania, downstream to the Interstate
86 Bridge in the village of Allegany, in Cattaraugus County, New York.
The Olean Creek portion of this unit includes approximately 8 rmi (14
rkm) of Olean Creek from its confluence with Oil Creek in the town of
Hinsdale downstream to the confluence with Allegheny River in the city
of Olean, in Cattaraugus County, New York. The Oil Creek portion of
this unit includes approximately 7 rmi (11 rkm) of Oil Creek from the
Interstate 86 Bridge near the Cattaraugus County/Allegany County line
in New York downstream to its confluence with Olean Creek in the town
of Hinsdale, in Cattaraugus County, New York. The Oswayo Creek portion
of this unit includes approximately 12 rmi (19 rkm) of Oswayo Creek its
confluence with Honeoye Creek in Potter County, Pennsylvania,
downstream to its confluence with Allegheny River just west of the
village of Portville in Cattaraugus County, New York). The Honeoye
Creek portion of this unit includes approximately 7 rmi (11 rkm) of
Honeoye Creek from the New York/Pennsylvania State Line in Allegany
County, New York, and Potter County, Pennsylvania, downstream to its
confluence with Oswayo Creek. The unit includes the river channel up to
the ordinary high-water mark.
Approximately 17.2 percent (14 rmi (22 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 82.8 percent (68 rmi (109 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the New York
State Office of Parks, Recreation and Historic Preservation and the
Pennsylvania Game Commission.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants and
resource

[[Page 22611]]

extraction; reduced connectivity due to barriers; habitat degradation
and loss due to urbanization, sedimentation, and stream channelization;
and the presence of invasive species.
RABE 10: Middle Allegheny River
RABE 10 consists of 176 rmi (283 rkm) of the Allegheny River and
Oil Creek in Armstrong, Butler, Clarion, Forest, Venango, Warren, and
Westmoreland Counties, Pennsylvania. The Allegheny River portion of
this unit extends approximately 171 rmi (275 rkm) from the Kinzua Dam
in Warren County, Pennsylvania, downstream to the mouth of the
Kiskiminetas River in Armstrong and Westmoreland Counties,
Pennsylvania. The Oil Creek portion of this unit includes approximately
5 rmi (8 rkm) from the Oil Creek State Park Ice Control Dam in Venango
County, Pennsylvania, downstream to Oil Creek's confluence with the
Allegheny River in Oil City, Venango County, Pennsylvania. The unit
includes the river channel up to the ordinary high-water mark.
Approximately 24.4 percent (43 rmi (74 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 75.6 percent (133 rmi (209 rkm)) are
in private ownership. Adjacent Federal lands are owned or managed by
the U.S. Forest Service and the Service. Adjacent State lands are owned
or managed by the Pennsylvania Bureau of Forestry and the Pennsylvania
Game Commission. The unit partially overlaps with designated critical
habitat for the federally threatened longsolid (Fusconaia subrotunda)
(see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023), the federally
threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30,
2015), the federally endangered sheepnose, and the federally endangered
snuffbox, and proposed critical habitat for the proposed endangered
salamander mussel (88 FR 57224, August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
reduced connectivity due to barriers; habitat degradation and loss due
to urbanization, sedimentation, and stream channelization; and the
presence of invasive species.
RABE 11: French Creek
RABE 11 consists of 100 rmi (161 rkm) of French Creek, LeBoeuf
Creek, Muddy Creek, and Cussewago Creek in Crawford, Erie, Mercer, and
Venango Counties, Pennsylvania. The French Creek portion of this unit
includes 77 rmi (124 rkm) of French Creek from the Union City Reservoir
Dam northeast of Union City (Erie County, Pennsylvania) downstream to
its confluence with the Allegheny River near the city of Franklin
(Venango County, Pennsylvania). The LeBoeuf Creek portion of this unit
includes 3 rmi (5 rkm) of LeBoeuf Creek from the State Highway 97
Bridge in Waterford Township downstream to its confluence with French
Creek in LeBoeuf Township, in Erie County, Pennsylvania. The Muddy
Creek portion of this unit includes 14 rmi (23 rkm) of Muddy Creek from
Pennsylvania Highway 77 near the unincorporated community of Little
Cooley downstream to its confluence with French Creek east of the
borough of Cambridge Springs, in Crawford County, Pennsylvania. The
Cussewago Creek portion of this unit includes 6 rmi (10 rkm) of
Cussewago Creek from the Rogers Ferry Road Bridge in Hayfield Township
downstream to its confluence with French Creek in the city of
Meadville, in Crawford County, Pennsylvania. The unit includes the
river channel up to the ordinary high-water mark.
Approximately 17.3 percent (17 rmi (27 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 82.7 percent (83 rmi (134 rkm)) are in
private ownership. Adjacent Federal lands are owned or managed by the
Service. Adjacent State lands are owned or managed by the Pennsylvania
Game Commission. The unit partially overlaps with designated critical
habitat for the federally threatened longsolid (see 50 CFR 17.95(f) and
88 FR 14794, March 9, 2023), the federally threatened rabbitsfoot (see
50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), the federally
endangered sheepnose, and the federally endangered snuffbox mussel, and
proposed critical habitat for the proposed endangered salamander mussel
(88 FR 57224; August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants and
resource extraction; habitat degradation and loss due to urbanization,
sedimentation, and stream channelization; the presence of invasive
species; and the loss of riparian buffer zones.
RABE 12: Little Darby Creek
RABE 12 consists of 21 rmi (35 rkm) of Little Darby Creek in
Madison and Union Counties, Ohio. This unit extends from the Ohio
Highway 161 Bridge near the unincorporated community of Chuckery (Union
County, Ohio) downstream to the U.S. Highway 40 Bridge near the village
of West Jefferson (Madison County, Ohio). The unit includes the river
channel up to the ordinary high-water mark.
Approximately 19.6 percent (4 rmi (7 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State)
ownership, and 80.4 percent (17 rmi (28 rkm)) are in private ownership.
Adjacent State lands are owned or managed by the Ohio Department of
Natural Resources. The unit fully overlaps with designated critical
habitat for the federally threatened rabbitsfoot (see 50 CFR 17.95(f)
and 80 FR 24692, April 30, 2015) and the federally endangered snuffbox
mussel.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization, sedimentation, and
stream channelization; and the presence of invasive species.
RABE 13: Big Darby Creek
RABE 13 consists of 38 rmi (61 rkm) of Big Darby Creek in Franklin,
Madison, and Union Counties, Ohio. This unit extends from the Highway
36 Bridge in the village of Milford Center (Union County, Ohio)
downstream to the State Route 665 Bridge (London Groveport Road) by the
unincorporated community of Darbydale (Franklin County, Ohio). The unit
includes the river channel up to the ordinary high-water mark.
Approximately 36.8 percent (14 rmi (22 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 63.2 percent (24 rmi (39 rkm)) are in private
ownership. Big Darby Creek is a State Scenic River, and adjacent State
lands are owned or managed by the Ohio Department of Natural Resources.
The unit fully overlaps with designated critical habitat for the
federally endangered snuffbox mussel.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization, sedimentation, and
stream channelization; reduced connectivity due to a barrier; and the
presence of invasive species.

[[Page 22612]]

RABE 14: Great Miami River
RABE 14 consists of approximately 11 rmi (18 rkm) of the Great
Miami River in Logan and Shelby Counties, Ohio. This unit extends from
the dam at Riverside Park in village of Quincy (Logan County, Ohio)
downstream to the Route 47 Bridge (Riverside Drive) in city of Sidney
(Shelby County, Ohio). The unit includes the river channel up to the
ordinary high-water mark.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization, sedimentation, and
stream channelization; reduced connectivity due to barriers; and the
presence of invasive species.
RABE 15: Tippecanoe River
RABE 15 consists of 47 rmi (76 rkm) of the Tippecanoe River in
Carroll, Pulaski, Tippecanoe, and White Counties, Indiana. This unit is
composed of two subunits, and each subunit includes the river channel
up to the ordinary high-water mark.
Subunit RABE 15a includes 28 rmi (45 rkm) of the Tippecanoe River
from the State Highway 14 Bridge near the town of Winamac (Pulaski
County, Indiana) downstream to the Lowes Bridge Road crossing in White
County, Indiana.
Subunit RABE 15b includes 19 rmi (31 rkm) of the Tippecanoe River
from the Oakdale Dam in Carroll County, Indiana, downstream to the
confluence of the Tippecanoe River with the Wabash River northeast of
the town of Battle Ground (Tippecanoe County, Indiana).
Approximately 6.6 percent (3 rmi (5 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 93.4 percent (44 rmi (71 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Indiana
Department of Natural Resources. Both subunits partially overlap with
designated critical habitat for the federally threatened rabbitsfoot
(see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), the federally
threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794; March
9, 2023), the federally endangered sheepnose, and proposed critical
habitat for the proposed endangered salamander mussel (88 FR 57224,
August 22, 2023), and fully overlap with designated critical habitat
for the federally endangered snuffbox mussel.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization, sedimentation, and
stream channelization; reduced connectivity due to barriers; and the
presence of invasive species.

II. Sheepnose

All 11 units for sheepnose are considered occupied by the species
at the time of listing and contain all of the physical or biological
features essential to the species' conservation.
SHNO 1: Lower Chippewa River
SHNO 1 consists of 57 rmi (92 rkm) of the lower Chippewa River in
Buffalo, Dunn, Eau Claire, and Pepin Counties, Wisconsin. This unit
extends from the confluence of the lower Chippewa River with the Eau
Clair River (Eau Claire County, Wisconsin), downstream to its
confluence with the Mississippi River (Buffalo/Pepin Counties,
Wisconsin). The unit includes the river channel up to the ordinary
high-water mark.
Approximately 63.0 percent (36 rmi (58 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 37.0 percent (21 rmi (34 rkm)) are in
private ownership. Adjacent Federal lands are owned or managed by the
Service as part of the Upper Mississippi River National Wildlife
Refuge, and adjacent State lands are owned or managed by the Wisconsin
Department of Natural Resources. This unit partially overlaps with
proposed critical habitat for the proposed endangered salamander mussel
(88 FR 57224; August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants,
and reduced connectivity due to barriers.
SHNO 2: Kankakee River
SHNO 2 consists of 51 rmi (82 rkm) of the Kankakee River in Grundy,
Kankakee, and Will Counties, Illinois. This unit extends from the
confluence of the Kankakee River with West Creek (Kankakee County,
Illinois) downstream to its confluence with the Illinois River (Grundy
County, Illinois). The unit includes the river channel up to the
ordinary high-water mark.
Approximately 54.9 percent (28 rmi (45 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State, and
local) ownership, and 45.1 percent (23 rmi (37 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Illinois
Department of Natural Resources.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants and
sedimentation, and in-stream gravel mining.
SHNO 3: Meramec and Bourbeuse Rivers
SHNO 3 consists of 153 rmi (246 rkm) of the Meramec and Bourbeuse
Rivers in Franklin, Jefferson, and Saint Louis Counties, Missouri. This
unit consists of 90 rmi (145 rkm) of the Meramec River from its
confluence with Rye Creek (Franklin County, Missouri) downstream to its
confluence with Mississippi River (Jefferson County, Missouri). SHNO 3
also includes 63 rmi (101 rkm) of the Bourbeuse River from its
confluence with Little Creek downstream to its confluence with the
Meramec River, in Franklin County, Missouri. The unit includes the
river channel up to the ordinary high-water mark.
Approximately 23.7 percent (36 rmi (58 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 76.3 percent (117 rmi (188 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Missouri
Department of Conservation and Missouri Department of Natural
Resources. This unit partially overlaps with designated critical
habitat for the federally endangered snuffbox, and the federally
endangered spectaclecase.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
reduced connectivity due to barriers; the presence of invasive species;
loss of riparian zones; and habitat degradation and loss due to
urbanization.
SHNO 4: Middle Allegheny-Tionesta
SHNO 4 consists of 28 rmi (45 rkm)) of the Allegheny River in
Forest and Venango Counties, Pennsylvania. This units extends from the
confluence of the Allegheny River with Tionesta Creek (Forest County,
Pennsylvania) downstream to its confluence with French Creek (Venango
County, Pennsylvania). The unit includes the

[[Page 22613]]

river channel up to the ordinary high-water mark.
Approximately 0.14 percent (0.04 rmi (0.06 rkm)) of the riparian
lands adjacent to, but not included in, this unit are in public (State)
ownership, and 99.86 percent (28 rmi (45 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the
Pennsylvania Fish and Boat Commission. The unit fully overlaps with
designated critical habitat for the federally threatened longsolid (see
50 CFR 17.95(f) and 88 FR 14794; March 9, 2023) and the federally
endangered rayed bean, and partially overlaps with the designated
critical habitat for the federally threatened rabbitsfoot (see 50 CFR
17.95(f) and 80 FR 24692, April 30, 2015).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants and
resource extraction; reduced connectivity due to barriers; habitat
degradation and loss due to urbanization, sedimentation, and stream
channelization; and the presence of invasive species.
SHNO 5: Upper Green
SHNO 5 consists of 157 rmi (253 rkm) of the Green River in Butler,
Edmonson, Green, Hart, Taylor, and Warren Counties, Kentucky. This unit
extends from the confluence of the Green River with the Barren River
(Taylor County, Kentucky) downstream to the Green River Dam (Butler
County, Kentucky). The unit includes the river channel up to the
ordinary high-water mark.
Approximately 22.5 percent (35 rmi (56 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 77.5 percent (122 rmi (196 rkm)) are
in private ownership. Adjacent Federal lands are owned or managed by
the U.S. Army Corps of Engineers and the National Park Service, and
adjacent State lands are owned or managed by the Kentucky Department of
Agriculture and the Kentucky Division of Water--Wild Rivers Program.
The unit partially overlaps with designated critical habitat for the
federally endangered diamond darter (Crystallaria cincotta) (see 50 CFR
17.95(e) and 78 FR 52364, August 22, 2013), the federally threatened
round hickorynut (see 50 CFR 17.95(f) and 88 FR 14794, March 9, 2023),
the federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR
24692, April 30, 2015), and the federally endangered spectaclecase, and
the proposed critical habitat for the proposed endangered Kentucky
creekshell (see 50 CFR 17.95(f) and 89 FR 76196, September 17, 2024),
and fully overlaps with designated critical habitat for the federally
threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794, March 9,
2023) and the federally endangered snuffbox.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of habitat and water quality from
impoundments and associated cold water discharges; siltation and
pollution due to improper timbering, sedimentation, and stream
channelization; resource extraction; water withdrawals; and
development.
SHNO 6: Tippecanoe River
SHNO 6 consists of 84 rmi (135 rkm) of the Tippecanoe River in
Fulton, Marshall, Pulaski, Starke, and White Counties, Indiana. This
unit extends from the confluence of the Tippecanoe River with Outlet
Creek (Marshall County, Indiana) downstream to Lake Freeman (White
County, Indiana). The unit includes the river channel up to the
ordinary high-water mark.
Approximately 10.35 percent (9 rmi (14 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State)
ownership, and 89.65 percent (75 rmi (121 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Indiana
Department of Natural Resources. The unit partially overlaps with
designated critical habitat for the federally threatened rabbitsfoot
(see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015), the federally
endangered rayed bean, the federally threatened round hickorynut (see
50 CFR 17.95(f) and 88 FR 14794; March 9, 2023), and the federally
endangered snuffbox mussel, and fully overlaps with the proposed
critical habitat for the proposed endangered salamander mussel (88 FR
57224, August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization, sedimentation, and
stream channelization; reduced connectivity due to barriers; and the
presence of invasive species.
SHNO 7: Walhonding River
SHNO 7 consists of 24 rmi (38 rkm) of the Walhonding River in
Coshocton County, Ohio. This unit extends from the confluence of the
Kokosing River and the Mohican River at the unincorporated community of
Walhonding downstream to the confluence of the Walhonding River with
the Tuscarawas River, in Coshocton County, Ohio. The unit includes the
river channel up to the ordinary high-water mark.
Approximately 4.9 percent (1 rmi (2 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 95.1 percent (22 rmi (36 rkm)) are in private
ownership. Adjacent State lands are owned or managed primarily by the
Ohio Department of Natural Resources. The unit partially overlaps with
designated critical habitat for the federally threatened rabbitsfoot
(see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants,
sedimentation, and stream channelization.
SHNO 8: Lower Tennessee River
SHNO 8 consists of 23 rmi (36 rkm) of the Tennessee River in
Livingston, Marshall, and McCracken Counties, Kentucky. This unit
extends from the Kentucky Dam (Marshall/Livingston Counties, Kentucky)
downstream to the confluence of the lower Tennessee River with the Ohio
River (McCracken County, Kentucky). The unit includes the river channel
up to the ordinary high-water mark.
Approximately 1.8 percent (0.4 rmi (0.6 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 98.2 percent (22 rmi (35 rkm)) are in private ownership.
The unit fully overlaps with designated critical habitat for the
federally threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692,
April 30, 2015).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to in-stream gravel
mining; degradation and loss of habitat due to dredging; reduced
connectivity due to barriers; and the presence of invasive species.
SHNO 9: Upper Clinch River
SHNO 9 consists of 106 rmi (171 rkm) of the Clinch River in
Russell, Scott, and Wise Counties, Virginia, and Hancock County,
Tennessee. This unit extends from the confluence of the upper Clinch
River with Thompson Creek (Russell County, Virginia) downstream to its

[[Page 22614]]

confluence with Big Creek (Hancock County, Tennessee). The unit
includes the river channel up to the ordinary high-water mark.
Approximately 6.1 percent (6 rmi (10 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal and
State) ownership, and 93.9 percent (100 rmi (161 rkm)) are in private
ownership. Adjacent Federal lands are owned or managed by the U.S.
Forest Service, and adjacent State lands are owned or managed by the
Tennessee Wildlife Resources Agency or the Virginia Department of
Conservation and Recreation. The unit fully overlaps with designated
critical habitat for the federally endangered Cumberlandian combshell
(Epioblasma brevidens), the federally endangered oyster mussel
(Epioblasma capsaeformis), the federally endangered purple bean
(Villosa perpurpurea), and the federally endangered rough rabbitsfoot
(Quadrula cylindrica strigillata) (see 50 CFR 17.95(f) and 69 FR 53136,
August 31, 2004); the federally endangered fluted kidneyshell, and the
federally endangered slabside pearlymussel (see 50 CFR 17.95(f) and 78
FR 59956, September 26, 2013); the federally threatened longsolid (see
50 CFR 17.95(f) and 88 FR 14794, March 9, 2023); the federally
threatened slender chub (Erimystax cahni) (see 50 CFR 17.95(e) and 42
FR 45526, September 9, 1977); the federally endangered snuffbox; and
the federally endangered spectaclecase; and partially overlaps with the
designated critical habitat for the federally threatened yellowfin
madtom (Noturus flavipinnis) (see 50 CFR 17.95(e) and 42 FR 45526,
September 9, 1977), and the proposed critical habitat for the federally
threatened sickle darter (Percina williamsi) (88 FR 4128; January 24,
2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of habitat and water quality from
downstream impoundment, mining discharges, siltation, contaminants,
resource extraction, and water withdrawals; urbanization; and the
presence of invasive species.
SHNO 10: Powell River
SHNO 10 consists of 63 rmi (101 rkm) of the Powell River in Lee
County, Virginia, and Claiborne and Hancock County, Tennessee. This
unit extends from the confluence of the Powell River with the Little
Yellow Branch (Lee County, Virginia) downstream to Highway 25E (Dixie
Highway E) (Claiborne County, Tennessee). The unit includes the river
channel up to the ordinary high-water mark.
Approximately 0.5 percent (0.3 rmi (0.5 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State)
ownership, and 99.5 percent (62 rmi (100 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Tennessee
Department of Environment and Conservation or the Virginia Department
of Conservation and Recreation. This unit fully overlaps with
designated critical habitat for the federally endangered Cumberlandian
combshell, federally endangered oyster mussel, federally endangered
purple bean, and federally endangered rough rabbitsfoot (see 50 CFR
17.95(f) and 69 FR 53136, August 31, 2004); the federally endangered
fluted kidneyshell, and the federally endangered slabside pearlymussel
(see 50 CFR 17.95(f) and 78 FR 59956, September 26, 2013); the
federally threatened slender chub and federally threatened yellowfin
madtom (see 50 CFR 17.95(e) and 42 FR 45526, September 9, 1977); and
the federally endangered snuffbox.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants,
urbanization, resource extraction, sedimentation, stream
channelization; reduced connectivity due to barriers; the presence of
invasive species; and changes to the hydrological regime.
SHNO 11: Big Sunflower River
SHNO 11 consists of 56 rmi (90 rkm) of the Big Sunflower River in
Bolivar and Sunflower Counties, Mississippi. This unit begins where
Merigold-Drew Road crosses the Big Sunflower River (Bolivar County,
Mississippi) and extends downstream to the confluence of the Big
Sunflower River with the Quiver River (Sunflower County, Mississippi).
The unit includes the river channel up to the ordinary high-water mark.
Approximately 4.1 percent (2 rmi (4 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal and
State) ownership, and 95.9 percent (54 rmi (86 rkm)) are in private
ownership. Adjacent Federal lands are owned or managed by the NRCS.
Adjacent State lands are owned or managed by the Mississippi Secretary
of State and Mississippi Forestry Commission. The unit partially
overlaps with designated critical habitat for the federally threatened
rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30, 2015).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants and
sedimentation; degradation and loss of habitat due to dredging and
stream channelization; and changes to the hydrological regime.

III. Snuffbox

All 38 units for snuffbox are considered occupied by the species at
the time of listing and contain all of the physical or biological
features essential to the species' conservation.
SNBO 1: Wolf River
SNBO 1 consists of 8 rmi (13 rkm) of the Wolf River in Shawano
County, Wisconsin. This unit extends from the Shawano Dam downstream to
the County Road CCC Bridge near the town of Waukechon, in Shawano
County, Wisconsin. The unit includes the river channel up to the
ordinary high-water mark.
Approximately 17.0 percent (1 rmi (2 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 83.0 percent (7 rmi (11 rkm)) are in
private ownership. Adjacent Federal land is owned or managed by the
Bureau of Land Management. Adjacent State lands are owned or managed by
the Wisconsin Department of Natural Resources.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization; reduced connectivity
due to barriers; impacts to the hydrological regime; and the presence
of invasive species.
SNBO 2: Embarrass River
SNBO 2 consists of 18 rmi (29 rkm) of the Embarrass River, South
Branch Embarrass River, and North Branch Embarrass River in Shawano
County, Wisconsin. This unit is composed of two subunits, and each
subunit includes the river channel up to the ordinary high-water mark.
Subunit SNBO 2a includes approximately 11 rmi (18 rkm) of the South
Branch Embarrass River in Shewano County, Wisconsin, from Spaulding
Street (County Road M) in Tigerton downstream to its confluence with
Embarrass River in the town of Grant.

[[Page 22615]]

Subunit SNBO 2b includes approximately 7 rmi (11 rkm) of the
Embarrass River and the North Fork Embarrass River in Shawano County,
Wisconsin. The Embarrass River includes approximately 5 rmi (8 rkm) of
the Embarrass River and extends from the Caroline Dam in the town of
Grant downstream to its confluence with North Branch Embarrass River,
in Shawano County, Wisconsin. The North Branch Embarrass River portion
of this unit includes approximately 2 rmi (3 rkm) of North Branch
Embarrass from the dam in the unincorporated community of Leopolis
downstream to its confluence with Embarrass River, in Shawano County,
Wisconsin.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization; reduced connectivity
due to barriers; impacts to the hydrological regime; and the presence
of invasive species.
SNBO 3: Little Wolf River
SNBO 3 consists of 12 rmi (19 rkm) of the Little Wolf River in
Waupaca County, Wisconsin. This unit extends from the Manawa Mill Pond
Dam in the city of Manawa downstream to the Highway X Bridge in the
town of Mukwa, in Waupaca County, Wisconsin. The unit includes the
river channel up to the ordinary high-water mark.
All of the riparian lands adjacent to, but not included in, this
unit are in private ownership.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization; reduced connectivity
due to barriers; impacts to the hydrological regime; and the presence
of invasive species.
SNBO 4: Grand River (Michigan)
SNBO 4 consists of 41 rmi (65 rkm) of the Grand River and the Flat
River in Ionia and Kent Counties, Michigan. The Grand River portion of
this unit includes 40 rmi (64 rkm) of the Grand River and extends from
the Webber Dam upstream of the village of Lyons (Ionia County,
Michigan) downstream to its confluence with Thornapple River in the
unincorporated community of Ada (Kent County, Michigan). The Flat River
portion of this unit includes 0.5 rmi (0.8 rkm) of the Flat River from
West State Highway 21 in the city of Lowell downstream to its
confluence with Grand River in the city of Lowell, in Kent County,
Michigan. The unit includes the river channel up to the ordinary high-
water mark.
Approximately 33.5 percent (14 rmi (22 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 66.5 percent (27 rmi (43 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Michigan
Department of Natural Resources.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to urbanization; reduced connectivity
due to barriers; and the presence of invasive species.
SNBO 5: Clinton River
SNBO 5 consists of 8 rmi (13 rkm) of the Clinton River in Oakland
County, Michigan. This unit extends from downstream of the fish
hatchery at Waterford Township downstream to Cass Lake east of the
unincorporated community of Four Towns, in Oakland County, Michigan.
The unit includes the river channel up to the ordinary high-water mark.
Approximately 11.0 percent (0.9 rmi (1 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 89.0 percent (7 rmi (12 rkm)) are in private ownership.
The unit fully overlaps with designated critical habitat for the
federally endangered rayed bean and partially overlaps with proposed
critical habitat for the proposed endangered salamander mussel (88 FR
57224; August 22, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
habitat degradation and loss due to the amount of impervious surface,
urbanization, and the lack of canopy cover and vegetative cover in the
riparian buffer; reduced connectivity due to barriers; and the presence
of invasive species.
SNBO 6: Huron River
SNBO 6 consists of 16 rmi (26 rkm) of the Huron River in Livingston
County, Michigan. This unit extends from Strawberry Lake downstream to
the Kent Lake Dam, in Livingston County, Michigan. The unit includes
the river channel up to the ordinary high-water mark.
Approximately 55.5 percent (9 rmi (14 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 44.5 percent (7 rmi (12 rkm)) are in private
ownership. Adjacent State lands are owned or managed by the Michigan
Department of Natural Resources.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants;
reduced connectivity due to barriers; and the presence of invasive
species.
SNBO 7: Grand River (Ohio)
SNBO 7 consists of 23 rmi (37 rkm) of the Grand River in Ashtabula
and Lake Counties, Ohio. This unit extends from the Harpersfield Dam in
the unincorporated community of Harpersfield (Ashtabula County, Ohio)
downstream to the Norfolk and Western Railroad Trestle (Lake County,
Ohio). The unit includes the river channel up to the ordinary high-
water mark.
Approximately 33.1 percent (8 rmi (12 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (local)
ownership, and 66.9 percent (16 rmi (25 rkm)) are in private ownership.
This unit fully overlaps with designated critical habitat for the
federally threatened round hickorynut (see 50 CFR 17.95(f) and 88 FR
14794, March 9, 2023).
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of habitat and water quality from
impoundments, domestic and industrial pollution due to human
development, resource extraction, water withdrawals, and wastewater
treatment plants; and the presence of invasive species.
SNBO 8: Allegheny River
SNBO 8 consists of 35 rmi (57 rkm) of the Allegheny River in
Venango County, Pennsylvania. This unit extends from the Allegheny
River's confluence with French Creek near city of Franklin downstream
to Interstate 80 near the borough of Emlenton, in Venango County,
Pennsylvania. The unit includes the river channel up to the ordinary
high-water mark.
Approximately 18.6 percent (6 rmi (11 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (State and
local) ownership, and 81.4 percent (29 rmi (46 rkm)) are in private
ownership. Adjacent State lands

[[Page 22616]]

are owned or managed by the Pennsylvania Bureau of Forestry and the
Pennsylvania Fish and Boat Commission. The unit fully overlaps with
designated critical habitat for the federally threatened longsolid (see
50 CFR 17.95(f) and 88 FR 14794; March 9, 2023), the federally
threatened rabbitsfoot (see 50 CFR 17.95(f) and 80 FR 24692, April 30,
2015), and the federally endangered rayed bean, and partially overlaps
with the critical habitat designation for the federally endangered
sheepnose.
The features essential to the conservation of this species may
require special management considerations or protection to reduce the
following threats: degradation of water quality due to contaminants,
sedimentation, stream channelization, and resource extraction; reduced
connectivity due to barriers (e.g., locks and dams); channelization;
and the presence of invasive species.
SNBO 9: French Creek
SNBO 9 consists of 130 rmi (209 rkm) of French Creek, West Branch
French Creek, LeBoeuf Creek, Cussewago Creek, Woodcock Creek, Muddy
Creek, and Conneaut Outlet in Erie, Crawford, Lebanon, Mercer, and
Venango Counties, Pennsylvania. SNBO 9 includes two subunits, and each
subunit includes the river channel up to the ordinary high-water mark.
Subunit SNBO 9a includes 19 rmi (30 rkm) of the West Branch French
Creek portion in Erie County, Pennsylvania from the Aston Road Bridge
in Greenfield Township just west of the New York/Pennsylvania State
line downstream to its confluence with French Creek in Wattsburg.
Subunit SNBO 9b includes 111 rmi (179 rkm) of the French Creek,
LeBoeuf Creek, Cussewago Creek, Woodcock Creek, Muddy Creek, and
Conneaut Outlet in Erie, Crawford, Mercer, and Venango Counties,
Pennsylvania. The French Creek portion of this unit includes 75 rmi
(121 rkm) from the Union City Reservoir Dam northeast of Union City
(Erie County, Pennsylvania) downstream to its confluence with Allegheny
River near the city of Franklin (Venango County, Pennsylvania). The
LeBoeuf Creek portion of this unit includes 3 rmi (5 rkm) in Erie
County, Pennsylvania, from U.S. Highway 19 downstream to its confluence
with French Creek in Le Boeuf Township. The Cussewago Creek portion of
this unit includes 1 rmi (2 rkm) in Crawford County, Pennsylvania, from
Dunham Road in the borough of Fredericksburg downstream to its
confluence with French Creek in the city of Meadville. The Woodcock
Creek portion of this unit includes 4 rmi (6 rkm) from the Woodcock Dam
downstream to its confluence with French Creek in the borough of
Saegertown, in Crawford County, Pennsylvania. The Muddy Creek portion
of this unit includes 14 rmi (22 rkm) from Pennsylvania Highway 77 near
unincorporated community of Little Cooley downstream to its confluence
with French Creek east of the borough of Cambridge Springs, in Crawford
County, Pennsylvania. The Conneaut Outlet portion of this unit includes
14 rmi (23 rkm) from Conneaut Lake downstream to its confluence with
French Creek in Fairfield Township, in Crawford County, Pennsylvania.
Approximately 23.8 percent (31 rmi (50 rkm)) of the riparian lands
adjacent to, but not included in, this unit are in public (Federal,
State, and local) ownership, and 76.2 percent (99 rmi (160 km)) are in
private ownership. Adjacent Federal lands are owned or managed by the
Service. Adjacent State lands are owned or managed by the Pennsylvania
Fish and Boat Commission and the Pennsylvania Game Commission. Both
subunits partially overlap with designated critical habitat for the
federally threatened longsolid (see 50 CFR 17.95(f) and 88 FR 14794;
March 9, 2023), the federally threatened rabbitsfoot (see 50 CFR
17.95(f) and 80 FR 24692, April 30, 2015), the federally endangered
rayed bean, and the federally endangered sheepnose, and proposed
critical habitat for the proposed endangered

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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.