[Federal Register Volume 88, Number 46 (Thursday, March 9, 2023)]
[Rules and Regulations]
[Pages 14794-14869]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-03998]



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Vol. 88

Thursday,

No. 46

March 9, 2023

Part III





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





Endangered and Threatened Wildlife and Plants; Threatened Species 
Status With Section 4(d) Rule for Longsolid and Round Hickorynut and 
Designation of Critical Habitat; Final Rule

  Federal Register / Vol. 88 , No. 46 / Thursday, March 9, 2023 / Rules 
and Regulations  

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R4-ES-2020-0010; FF09E21000 FXES1111090FEDR 234]
RIN 1018-BD32


Endangered and Threatened Wildlife and Plants; Threatened Species 
Status With Section 4(d) Rule for Longsolid and Round Hickorynut and 
Designation of Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine 
threatened species status under the Endangered Species Act of 1973 
(Act), as amended, for the longsolid (Fusconaia subrotunda) and round 
hickorynut (Obovaria subrotunda), freshwater mussels. We also designate 
critical habitat for both species. For the longsolid, in total, 
approximately 1,115 river miles (1,794 river kilometers) fall within 12 
units of critical habitat in Pennsylvania, Kentucky, West Virginia, 
Virginia, Tennessee, and Alabama. For the round hickorynut, in total, 
approximately 921 river miles (1,482 river kilometers) fall within 14 
units of critical habitat in Pennsylvania, Ohio, Indiana, Kentucky, 
West Virginia, Tennessee, Alabama, and Mississippi. We also finalize a 
rule under the authority of section 4(d) of the Act for both species 
that provides measures that are necessary and advisable to provide for 
the conservation of these species.

DATES: This rule is effective April 10, 2023.

ADDRESSES: This final rule is available on the internet at https://www.regulations.gov. Comments and materials we received are available 
for public inspection at https://www.regulations.gov at Docket No. FWS-
R4-ES-2020-0010.
    Supporting materials we used in preparing this rule, such as the 
species status assessment reports and supporting information that we 
developed for the critical habitat designation, are available at 
https://www.regulations.gov at Docket No. FWS-R4-ES-2020-0010. For the 
critical habitat designation, the coordinates or plot points or both 
from which the maps are generated are included in the decision file and 
are available at https://www.regulations.gov at Docket No. FWS-R4-ES-
2020-0010, and on the Service's Environmental Conservation Online 
System (ECOS) website at https://ecos.fws.gov/ecp/species/9880 and 
https://ecos.fws.gov/ecp/species/9879.

FOR FURTHER INFORMATION CONTACT: Janet Mizzi, Field Supervisor, U.S. 
Fish and Wildlife Service, Asheville Ecological Services Field Office, 
160 Zillicoa St., Asheville, NC 28801; telephone 828-258-3939. 
Individuals in the United States who are deaf, deafblind, hard of 
hearing, or have a speech disability may dial 711 (TTY, TDD, or 
TeleBraille) to access telecommunications relay services. Individuals 
outside the United States should use the relay services offered within 
their country to make international calls to the point-of-contact in 
the United States.

SUPPLEMENTARY INFORMATION: 

Executive Summary

    Why we need to publish a rule. Under the Act, a species warrants 
listing if it meets the definition of an endangered species (in danger 
of extinction throughout all or a significant portion of its range) or 
a threatened species (likely to become endangered within the 
foreseeable future throughout all or a significant portion of its 
range). If we determine that a species warrants listing, we must list 
the species promptly and designate the species' critical habitat to the 
maximum extent prudent and determinable. We have determined that the 
longsolid and round hickorynut meet the definition of threatened 
species; therefore, we are listing them as such and finalizing a 
designation of their critical habitat. Both listing a species as an 
endangered or threatened species and designating critical habitat can 
be completed only by issuing a rule through the Administrative 
Procedure Act rulemaking process (5 U.S.C. 551 et seq.).
    What this document does. This rule lists the longsolid and round 
hickorynut as threatened species, and issues regulations under section 
4(d) of the Act (a ``4(d) rule'') for the conservation of both species. 
This rule designates critical habitat for the longsolid in 12 units 
totaling approximately 1,115 river miles (mi) (1,794 river kilometers 
(km)) within portions of 7 counties in Pennsylvania, 16 counties in 
Kentucky, 10 counties in West Virginia, 4 counties in Virginia, 6 
counties in Tennessee, and 3 counties in Alabama. Additionally, this 
rule designates critical habitat for the round hickorynut in 14 units 
totaling approximately 921 river mi (1,482 river km) within portions of 
2 counties in Pennsylvania, 3 counties in Ohio, 4 counties in Indiana, 
18 counties in Kentucky, 11 counties in West Virginia, 3 counties in 
Tennessee, 3 counties in Alabama, and 1 county in Mississippi.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species based on any of five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that the longsolid and round 
hickorynut are threatened species due to the following threats: habitat 
degradation or loss (Factor A) from a variety of sources (e.g., dams 
and other barriers, resource extraction); degraded water quality from 
chemical contamination and erosion from development, agriculture, 
mining, and forest conversion (Factor A); direct mortality from 
dredging (Factor E); residual impacts (reduced population size) from 
historical harvest (Factor B); and the proliferation of invasive, 
nonnative species (Factor E). These threats also contribute to the 
negative effects associated with the species' small population sizes 
(Factor E).
    Section 4(a)(3) of the Act requires the Secretary of the Interior 
(Secretary) to designate critical habitat concurrent with listing 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 proposed listing and critical habitat rule (85 
FR 61384) for the longsolid and round hickorynut published on September 
29, 2020, for a

[[Page 14795]]

detailed description of previous Federal actions concerning these 
species.

Peer Review

    A species status assessment (SSA) team prepared SSA reports for the 
longsolid and round hickorynut. 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 each of the species, including the 
impacts of past, present, and future factors (both negative and 
beneficial) affecting them.
    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 
2016, memorandum updating and clarifying the role of peer review of 
listing actions under the Act, we solicited independent scientific 
review of the information contained in the SSA reports. As discussed in 
the proposed rule, we sent the SSA reports to 10 independent peer 
reviewers on both the longsolid and round hickorynut and received 3 
responses on the longsolid SSA report, and no responses on the round 
hickorynut SSA report. The peer reviews for the longsolid SSA report 
can be found at https://www.regulations.gov at Docket No. FWS-R4-ES-
2020-0010. In preparing the proposed rule, we incorporated the results 
of these reviews, as appropriate; both SSA reports were 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 Peer Reviewer Comments 
section of this final rule.

Summary of Changes From the Proposed Rule

    This final rule incorporates several changes from what was 
contained in our proposed rule (85 FR 61384; September 29, 2020) based 
on the comments we received during the comment period. Minor, 
nonsubstantive changes and corrections were made throughout this rule 
and in the SSA reports in response to comments (e.g., updated range map 
for round hickorynut based on survey information in Ohio, revised 
forest conversion section in the discussion of threats). The 
information we received during the comment period did not change our 
determination that the longsolid and round hickorynut are threatened 
species.
    We received substantive comments on the proposed listing and 
proposed 4(d) rule (see Summary of Comments and Recommendations, 
below), and we made changes as follows:
     We received comments from multiple State agencies across 
the ranges of the longsolid and round hickorynut. The State agencies 
generally concurred with our methods and conclusions, and provided 
additional information, clarifications, and suggestions associated with 
threats to the longsolid and round hickorynut. Minor edits associated 
with threats and their association with populations in West Virginia 
have been incorporated into the preamble of this rule, and additional 
citations have been added to support statements regarding contaminants 
and resource extraction and their effects on stream habitats and 
macroinvertebrates. These added citations are Pond et al. (2008) and 
Entrekin et al. (2015). Additionally, special management 
recommendations for the nonnative round goby (Neogobius melanostomus) 
have been incorporated into the discussion of the longsolid's French 
Creek critical habitat unit (Unit LS 1) in Pennsylvania.
     We received comments requesting clarification of 
broodstocking activities as they relate to the 4(d) exception 
associated with conservation and restoration efforts by State wildlife 
agencies. Accordingly, the first exception for incidental take 
associated for both species' 4(d) rules clarifies this activity 
includes population monitoring, relocation, and collection of 
broodstock; tissue collection for genetic analysis; captive 
propagation; and subsequent stocking into currently occupied and 
unoccupied areas within both species' historical ranges.
     We received comments requesting clarification on the third 
exception in the 4(d) rule for bank restoration projects that use 
bioengineering methods to reduce bank erosion and instream 
sedimentation and improve habitat conditions for both species. 
Specifically, the commenter indicated, and we agree, that this 
exception should be referred to as bank stabilization projects, which 
may include channel restoration activities, and relocation of mussels 
prior to implementation of these types of projects may be (as opposed 
to must be) necessary. Accordingly, this exception of the 4(d) rule 
reflects these changes.
     Several commenters indicated that the Service should 
consider forest management best management practices (BMPs; i.e., 
practices that reduce the amount of nonpoint pollution from forest 
management) as part of the overall conservation benefit for the 
species, account for these beneficial actions in any threat analysis, 
and incorporate an associated exception into the 4(d) rules for both 
species. Additionally, Warrington et al. (2017) was described as being 
cited erroneously in the proposed rule's preamble. Forested watersheds 
contribute to the current condition of each species and have been 
factored in as a positive factor (i.e., benefit) in the SSAs and 
proposed rule. State-approved forest management BMPs vary across the 
large geographic areas occupied by the longsolid and round hickorynut, 
but we support and encourage their use throughout the species' ranges. 
Accordingly, this final rule includes an exception to the prohibitions 
in both species' 4(d) rules for State-approved forest management BMPs 
in response to public comments we received on the proposed rule.
    We also note that forestry activities were not a primary threat in 
our current and future condition analyses, and that the conversion of 
forested habitats to other land uses, such as agriculture or urban 
development, contribute to greater habitat and water quality 
degradation than forest management. Clarity regarding forest conversion 
to other land uses, not forestry, and its contribution to freshwater 
mussel habitat degradation and loss has been incorporated into the 
preamble of this rule. Several populations of the longsolid and round 
hickorynut occur on U.S. Forest Service lands; therefore, any actions 
that may affect these populations are subject to section 7 consultation 
under the Act (16 U.S.C. 1531 et seq.).
    This rule does not make any changes to the boundaries of the 
proposed critical habitat designation for either species based on 
public comments we received.

I. Final Listing Determination

Background

    Please refer to the September 29, 2020, proposed rule (85 FR 61384) 
and the SSA reports for full summaries of species information. These 
documents are available at https://www.regulations.gov under Docket No. 
FWS-R4-ES-2020-0010, and on the ECOS website at https://ecos.fws.gov/ecp/species/9880 and https://ecos.fws.gov/ecp/species/9879.
    The longsolid (Fusconaia subrotunda) is a freshwater river mussel 
belonging to the Unionidae family, also known as the naiads and pearly 
mussels. Longsolid adults are light brown in color, darkening with age. 
The shell is thick and medium-sized (up to 5 inches (in) (125 
millimeters (mm)), and typically has a dull sheen (Williams et al. 
2008, p. 322). There is variability in the inflation of the shell 
depending on population and latitudinal location

[[Page 14796]]

(Ortmann 1920, p. 272; Watters et al. 2009, p. 130).
    The longsolid is currently found in the Ohio, Cumberland, and 
Tennessee River basins, overlapping within the States of Alabama, 
Kentucky, New York, North Carolina, Ohio, Pennsylvania, Tennessee, 
Virginia, and West Virginia (Service 2018, appendix A; see figure 1, 
below). It is considered extirpated from Georgia, Indiana, and 
Illinois.
    Additionally, it is classified as an endangered species by the 
State of Ohio, and considered to have various levels of concern, 
imperilment, or vulnerability (see table 1-1 in the SSA report) by the 
States of Alabama, Kentucky, North Carolina, Pennsylvania, Tennessee, 
Virginia, and West Virginia.
BILLING CODE 4333-15-P

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[GRAPHIC] [TIFF OMITTED] TR09MR23.015

    Similar to the longsolid, the round hickorynut also belongs to the 
Unionidae family of naiads and pearly mussels. Round hickorynut adult 
mussels are greenish-olive to dark or chestnut brown, sometimes 
blackish in older individuals, and may have a yellowish band dorsally 
(Parmalee and Bogan 1998, p. 168). Inflation of the shell is variable 
depending on population and latitudinal location (Ortmann 1920, p. 272; 
Williams et al. 2008, p. 474). The shell is thick, solid, and up to 3 
in (75 mm) in length, but usually is less than 2.4 in (60 mm)

[[Page 14798]]

(Williams et al. 2008, p. 473; Watters et al. 2009, p. 209). A 
distinctive characteristic is that the shell is round in shape, nearly 
circular, and the umbo (the raised portion of the dorsal margin of a 
shell) is centrally located.
    Within the United States, the round hickorynut is currently found 
in the Great Lakes, Ohio, Cumberland, Tennessee, and Lower Mississippi 
River basins, overlapping within the States of Alabama, Indiana, 
Kentucky, Michigan, Mississippi, Ohio, Pennsylvania, Tennessee, and 
West Virginia (Service 2019, appendix A; see figure 2, below). It is 
considered extirpated from Georgia, Illinois, and New York. 
Additionally, it has State-level conservation status, ranging across 
various levels of concern, imperilment, or vulnerability (see table 1-1 
in the SSA report), in the States of Alabama, Indiana, Kentucky, 
Michigan, Pennsylvania, Tennessee, and West Virginia. The round 
hickorynut also occurs within the Canadian Province of Ontario, where 
it was listed as an endangered species in 2005, due to the loss of and 
significant declines in populations (Committee on the Status of Species 
at Risk in Ontario 2013, p. 4); a single remaining population (showing 
no recruitment (Morris 2018, pers. comm.)) occurs in Lake St. Clair and 
the East Sydenham River.

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[GRAPHIC] [TIFF OMITTED] TR09MR23.016


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BILLING CODE 4333-15-C
    Thorough reviews of the taxonomy, life history, ecology and State 
listing status of the longsolid and round hickorynut are presented in 
detail in the SSA reports (Service 2018, pp. 14, 15, 22-30; Service 
2019, pp. 14, 15, 22-29).

Regulatory and Analytical Framework

Regulatory Framework

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

Analytical Framework

    The SSA reports document the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of both species, including an assessment of potential 
threats to the species. The SSA reports do not represent our decision 
on whether either species should be listed as an endangered or 
threatened species under the Act. However, they do provide the 
scientific basis that informs our regulatory decisions, which involve 
the further application of standards within the Act and its 
implementing regulations and policies.
    To assess the longsolid's and round hickorynut's viability, we used 
the three conservation biology principles of resiliency, redundancy, 
and representation (Shaffer and Stein 2000, pp. 306-310). Briefly, 
resiliency is the ability of the species to withstand environmental and 
demographic stochasticity (for example, wet or dry, warm or cold 
years), redundancy is the ability of the species to withstand 
catastrophic events (for example, droughts, large pollution events), 
and representation is the ability of the species to adapt to both near-
term and long-term changes in its physical and

[[Page 14801]]

biological environment (for example, climate changes, pathogen). In 
general, species viability will increase with increases in resiliency, 
redundancy, and representation (Smith et al. 2018, p. 306). Using these 
principles, we identified the species' ecological requirements for 
survival and reproduction at the individual, population, and species 
levels, and described the beneficial and risk factors influencing the 
species' viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the individual species' life-
history needs. The next stage involved an assessment of the historical 
and current condition of the species' demographics and habitat 
characteristics, including an explanation of how the species arrived at 
its current condition. The final stage of the SSA involved making 
predictions about the species' responses to positive and negative 
environmental and anthropogenic influences. Throughout all of these 
stages, we used the best available information to characterize 
viability as the ability of a species to sustain populations in the 
wild over time. We use this information to inform our regulatory 
decision.
    The following is a summary of the key results and conclusions from 
the SSA reports for the longsolid and round hickorynut; the full SSA 
reports can be found on https://www.regulations.gov at Docket FWS-R4-
ES-2020-0010, and on the Service's ECOS website at https://ecos.fws.gov/ecp/species/9880 and https://ecos.fws.gov/ecp/species/9879.

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
longsolid and round hickorynut, their resources, and the threats that 
influence both species' current and future condition, in order to 
assess each species' overall viability and the risks to that viability.

Species Needs

    We assessed the best available information to identify the physical 
and biological needs to support individual fitness at all life stages 
for the longsolid and round hickorynut. Full descriptions of all needs 
are available in chapter 4 of the SSA reports (Service 2018, pp. 25-30; 
Service 2019, pp. 30-36), which can be found in docket number FWS-R4-
ES-2020-0010 on https://www.regulations.gov. Based upon the best 
available scientific and commercial information, and acknowledging 
existing ecological uncertainties (see section 4.3 in the SSA reports), 
the resource and demographic needs for both the longsolid and round 
hickorynut are characterized as:
     Clean, flowing water with appropriate water quality and 
temperate conditions, such as (but not limited to) dissolved oxygen 
above 2 to 3 parts per million (ppm), ammonia generally below 0.5 ppm 
total ammonia-nitrogen, temperatures generally below 86 degrees 
Fahrenheit ([deg]F) (30 degrees Celsius ([deg]C)), and (ideally) an 
absence of excessive total suspended solids and other pollutants.
     Natural flow regimes that vary with respect to timing, 
magnitude, duration, and frequency of river discharge events.
     Predominantly silt-free, stable sand, gravel, and cobble 
substrates.
     Suspended food and nutrients in the water column including 
(but not limited to) phytoplankton, zooplankton, protozoans, detritus, 
and dissolved organic matter.
     Availability of sufficient host fish numbers to provide 
for glochidia infestation and dispersal. Host fishes for the longsolid 
are currently unknown but likely include (but may not be limited to): 
minnows of the family Cyprinidae as well as potentially freshwater 
sculpins of the genus Cottus. Host fish species documented for the 
round hickorynut include the banded sculpin (Cottus carolinae), eastern 
sand darter (Ammocrypta pellucida), emerald darter (Etheostoma 
baileyi), greenside darter (Etheostoma blennioides), Iowa darter 
(Etheostoma exile), fantail darter (Etheostoma flabellare), Cumberland 
darter (Etheostoma gore), spangled darter (Etheostoma obama), variegate 
darter (Etheostoma variatum), blackside darter (Percina maculata), and 
frecklebelly darter (Percina stictogaster).
     Connectivity among populations. Although the species' 
capability to disperse is evident through historical occurrence of a 
wide range of rivers and streams, the fragmentation of populations by 
small and large impoundments has resulted in isolation and only patches 
of what once was occupied contiguous river and stream habitat. Genetic 
exchange occurs between and among mussel beds via sperm drift, host 
fish movement, and movement of mussels during high flow events. For 
genetic exchange to occur, connectivity must be maintained. Most 
freshwater mussels, including the longsolid and round hickorynut, are 
typically found in mussel beds that vary in size and are often 
separated by stream reaches in which mussels are absent or rare (Vaughn 
2012, p. 983). These species are often a component of a healthy mussel 
assemblage within optimal mussel habitats; therefore, the beds in which 
they occur are necessary for the species to be sufficiently resilient 
over time.

Current Conditions

    Current (and future) conditions are described using categories that 
estimate the overall condition of the longsolid and round hickorynut 
mussel populations. These categories include:
     High--Sufficiently resilient populations with evidence of 
recruitment and multiple age classes represented. They are likely to 
maintain viability and connectivity among populations, and populations 
are not linearly distributed (i.e., occur in tributary streams within a 
management unit). Populations are expected to persist in 20 to 30 years 
and beyond and withstand stochastic events. (Thriving; capable of 
expanding range.)
     Medium--Spatially restricted populations with limited 
connectivity and reduced levels of recruitment or age class structure. 
Resiliency is less than under high conditions, but the majority of 
populations (approximately 75 percent) are expected to persist beyond 
20 to 30 years. (Stable; not necessarily thriving or expanding its 
range.)
     Low--Small and highly restricted populations, with no 
evidence of recent recruitment or age class structure, and limited 
detectability. These populations have low resiliency, are not likely to 
withstand stochastic events, and potentially may be extirpated in 20 to 
30 years. Populations are linearly distributed within a management 
unit. (Surviving and observable, but population likely declining.)
    Given the longsolid's and round hickorynut's ranges include lengthy 
rivers, such as the Ohio, Allegheny, Cumberland, and Tennessee Rivers, 
all of which include populations fragmented primarily by dams, we 
identified separate populations for each hydrologic unit code (HUC) 
(Seaber et al. 1987, entire; U.S. Geological Survey 2018, entire) at 
the fourth of 12 levels (i.e., HUC-8 watershed). The HUC-8 watersheds 
are analogous to medium-sized river basins across the United States. 
Our analysis describes conditions relevant to longsolid and round 
hickorynut populations and the overarching HUC-8 watersheds, identified 
herein as a ``management unit.'' A management unit could harbor one or 
more populations. See chapter 2 in the SSA reports for further 
explanation of the analysis methodology (Service 2018, pp. 15-19; 
Service 2019, pp. 17-22).
Longsolid
    The longsolid's current range extends over nine States, including 
New York,

[[Page 14802]]

Pennsylvania, West Virginia, Ohio, Kentucky, Virginia, Tennessee, North 
Carolina, and Alabama; the species is now considered extirpated in 
Georgia, Illinois, and Indiana. This range encompasses three major 
river basins (the Ohio, Cumberland, and Tennessee basins); the species 
now no longer exists in the Great Lakes basin (loss of six historical 
populations and four management units). In addition, its representation 
in the Cumberland River basin is currently within a single population 
and management unit (loss of nine historical populations and eight 
management units). Overall, the longsolid is presumed extirpated from 
62 percent (100 of 160 populations) of its historically occupied 
populations, including 6 populations (the entirety) in the Great Lakes 
basin, 62 populations in the Ohio River basin, 8 populations in the 
Cumberland River basin, and 24 populations in the Tennessee River basin 
(see appendix B in the SSA report (Service 2018, pp. 131-154)). Of the 
current populations, 3 (5 percent) are estimated to be highly 
resilient, 8 (13 percent) are estimated to be moderately resilient, and 
49 (79 percent) are estimated to have low resiliency.
    The longsolid was once a common, occasionally abundant component of 
the mussel assemblage in rivers and streams where it is now extirpated. 
Examples include the Beaver River, Pennsylvania (Ortmann 1920, p. 276); 
Ohio River, Pennsylvania (Tolin 1987, p. 11); Mahoning River, 
Pennsylvania (Ortmann 1920 p. 276); Wabash River, Indiana/Illinois 
(Cummings et al. 1992, p. 46); Nolin River, Kentucky (Taylor 1983a, p. 
111); and the South Fork Holston River, Virginia/Tennessee (Parmalee 
and Pohemus 2004, p. 234). Significant declines of the longsolid have 
been observed and documented in the Ohio and Cumberland Rivers (Neel 
and Allen 1964, p. 434, Haag and Cicerello 2016, p. 139) and in the 
Muskingum River system, which harbors the last remaining populations 
(Muskingum, Tuscarawas, and Walhonding) in Ohio (Watters and Dunn 1993-
94, p. 252; Watters et al. 2009, p. 131).
Round Hickorynut
    The current range of the round hickorynut extends over nine States, 
including Alabama, Indiana, Kentucky, Michigan, Mississippi, Ohio, 
Pennsylvania, Tennessee, and West Virginia; the species is now 
considered extirpated in Georgia, Illinois, and New York. This range 
encompasses five major river basins (Great Lakes, Ohio River, 
Cumberland River, Tennessee River, and Lower Mississippi River). Round 
hickorynut representation in the Cumberland River basin is restricted 
to two linear populations within two management units, while it exists 
in the Lower Mississippi River basin in a single population. Therefore, 
while the species currently maintains representation from historical 
conditions, it is at immediate risk of losing 40 percent (2 of 5 
basins) of its representation due to these small, isolated populations 
under a high degree of threats from habitat loss and water quality 
degradation.
    Overall, the round hickorynut has lost approximately 232 of 301 
known populations (77 percent), and 102 of 138 management units (74 
percent). This includes 25 populations in the Great Lakes basin, 146 
populations in the Ohio River basin, 23 populations in the Cumberland 
River basin, 29 populations in the Tennessee River basin, and 9 
populations in the Lower Mississippi River basin (see appendix B in the 
SSA report (Service 2019, pp. 191-212)). Of the current populations, 4 
(6 percent) are estimated to be highly resilient, 16 (23 percent) are 
estimated to be moderately resilient, and 49 (71 percent) are estimated 
to have low resiliency.
    The round hickorynut was once a much more common, occasionally 
abundant component of the mussel assemblage in rivers and streams 
across much of the eastern United States. Population extirpations have 
been extensive and widespread within every major river basin where the 
round hickorynut is found. Surveys throughout eastern North America 
have not targeted the round hickorynut specifically, and as a result, 
there could have been additional population losses or declines that 
have gone undocumented. Conversely, it is possible that there are 
populations that have gone undetected. However, the majority of the 
species' range has been relatively well-surveyed for freshwater mussel 
communities, and the likelihood is low that substantial or stronghold 
populations remain undetected. Patterns of population extirpation and 
declines are pronounced, particularly in the Ohio River basin, which 
appears to be the basin most important for redundancy and 
representation for the species due to its documented historical 
distribution and remaining concentration of populations within the 
basin.
    Populations of the round hickorynut have been lost from entire 
watersheds and management units in which the species once occupied 
multiple tributaries, such as the Allegheny, Coal, Little Scioto, 
Miami, and Vermilion River management units in the Ohio River basin. 
The State of Ohio, for example, has lost 49 populations of round 
hickorynut, along with 17 management units (Watters et al. 2009, p. 
210). The species is also critically imperiled in Canada, and as a 
result, the future of the species in Canada may be reliant on hatchery-
supported activities or augmentation activities coordinated with the 
United States.
    Precipitous declines and extirpations of round hickorynut 
populations have been documented in the Great Lakes, Ohio, Cumberland, 
Tennessee, and Lower Mississippi basins. Chronological museum 
collections and published literature accounts of the species 
demonstrate that individuals were more abundant in populations and 
there were more populations across the range (see appendix D in the SSA 
report (Service 2019, pp. 214-238)). While this documentation could be 
a result of more intensive survey effort in the core of the species' 
distribution, regardless, the extirpation of formerly abundant and 
extensive populations, has been most pronounced in the Ohio and 
Cumberland basins.
    Examples of rivers where the round hickorynut is extirpated within 
these basins include: Crooked Creek, Pennsylvania (Ortmann 1913, p. 
298); West Branch Mahoning River, Ohio (Swart 1940, p. 42); Coal River, 
West Virginia (Carnegie Museum and University of Michigan Museum of 
Zoology records); Olentangy River, Ohio (Stein 1963, p. 109); Blaine 
Creek, Kentucky (Bay and Winford 1984, p. 19); Embarras River, Illinois 
(Parmalee 1967, p. 80); Big Vermilion River, Illinois (Parmalee 1967, 
p. 80); Cumberland River, Kentucky (Neel and Allen 1964, p. 442); 
Stones River, Tennessee (Ohio State University Museum records); and Red 
River, Tennessee/Kentucky (Ohio State University Museum records).

Threats Analysis

    The following discussions include evaluations of three threats and 
associated sources that are affecting the longsolid and round 
hickorynut and their habitats: (1) Habitat degradation or loss, (2) 
invasive and nonnative species, and (3) negative effects associated 
with small population size, including potential cumulative or 
synergistic effects (Service 2018 and 2019, chapter 6). We note that 
potential impacts associated with overutilization were evaluated, but 
we found no evidence of current effects on the species' viability 
(noting historical effects from harvest on the longsolid that no longer 
occur). In addition, potential impacts from disease, parasites, and 
predation, as well as potential impacts to host

[[Page 14803]]

species, were evaluated but were found to have minimal effects on 
viability of either species based on current knowledge (Service 2018, 
pp. 70, 73-74; Service 2019, pp. 91-95). Finally, we also considered 
effects associated with enigmatic population declines, which have been 
documented in freshwater river mussel populations since the 1960s; 
despite speculation and repeated aquatic organism surveys and water 
quality monitoring, the causes of these events are unknown (Haag 2019, 
p. 43). In some cases, the instream habitat often remains basically 
intact and continues to support other aquatic organisms such as fish 
and crayfish. Full descriptions of each of the threats and their 
sources, including specific examples across the species' range where 
threats are impacting the species or its habitat, are available in 
chapter 6 and appendix A of the SSA reports (Service 2018, pp. 43-76, 
134-157; Service 2019, pp. 58-96, 169-187).
    We note that, by using the SSA framework to guide our analysis of 
the scientific information documented in both the longsolid and round 
hickorynut SSA reports, we have not only analyzed individual effects on 
the two species, but we have also analyzed their potential cumulative 
effects. We incorporate the cumulative effects into our SSA analysis 
when we characterize the current and future condition of the species. 
To assess the current and future condition of each of the species, we 
undertake an iterative analysis that encompasses and incorporates the 
threats individually and then accumulates and evaluates the effects of 
all the relevant factors that may be influencing the species, including 
threats and conservation efforts. Because the SSA framework considers 
not just the presence of the factors, but to what degree they 
collectively influence risk to the entire species, our assessment 
integrates the cumulative effects of the factors and replaces a 
standalone cumulative effects analysis.

Habitat Degradation or Loss

Development/Urbanization

    Development and urbanization activities that may contribute to 
longsolid and round hickorynut habitat degradation and loss, including 
reduced water quality, occur throughout the species' range. The term 
``development'' refers to urbanization of the landscape, including (but 
not limited to) land conversion for residential, commercial, and 
industrial uses and the accompanying infrastructure. The effects of 
urbanization may include alterations to water quality, water quantity, 
and habitat (both in-stream and streamside) (Ren et al. 2003, p. 649; 
Wilson 2015, p. 424). Urban development can lead to increased 
variability in streamflow, typically increasing the extent and volume 
of water entering a stream after a storm and decreasing the time it 
takes for the water to travel over the land before entering the stream 
(Giddings et al. 2009, p. 1). Deleterious effects on streams (i.e., 
water collection on impervious surfaces that rapidly flows into storm 
drains and local streams), including those that may be occupied by the 
longsolid and round hickorynut include:
    (1) Water Quantity: Storm drains deliver large volumes of water to 
streams much faster than would naturally occur, often resulting in 
flooding and bank erosion that reshapes the channel and causes 
substrate instability, resulting in destabilization of bottom 
sediments. Increased, high-velocity discharges can cause species living 
in streams (including mussels) to become stressed, displaced, or killed 
by fast-moving water and the debris and sediment carried in it. 
Displaced individuals may be left stranded out of the water once 
floodwaters recede.
    (2) Water Quality: Pollutants (e.g., gasoline, oil drips, 
fertilizers) that accumulate on impervious surfaces may be washed 
directly into streams during storm events. Contaminants contained in 
point and non-point source discharges degrade water and substrate 
quality, and can result in reduced survival, growth, and reproduction 
of mussels.
    (3) Water Temperature: During warm weather, rain that falls on 
impervious surfaces becomes superheated and can stress or kill 
freshwater species when it enters streams.
    Other development-related impacts to the longsolid and round 
hickorynut, or their habitats, may occur as a result of:
     Water infrastructure. This includes water supply, 
reclamation, and wastewater treatment, which results in pollution point 
discharges to streams. Concentrations of contaminants (including 
nitrogen, phosphorus, chloride, insecticides, polycyclic aromatic 
hydrocarbons, and personal care products) increase with urban 
development (Giddings et al. 2009, p. 2; Bringolf et al. 2010, p. 
1,311).
     Utility crossings and right-of-way maintenance. Direct 
impacts from utility crossings include direct exposure or crushing of 
individuals, sedimentation, and habitat disturbance. The greatest 
cumulative impact involves cleared rights-of-way that result in direct 
runoff and increased stream temperature at the crossing location, and 
potentially promote maintenance utility and all-terrain vehicle access 
from the rights-of-way (which destroys banks and instream habitat, and 
thus can lead to increased erosion (see also Service 2017, pp. 48-49)).
     Anthropogenic activities. These types of activities may 
act to lower water tables, making the longsolid or round hickorynut 
susceptible to depressed flow levels. Water infrastructure (see above) 
and water withdrawals for irrigation, municipal, and industrial water 
supplies are an increasing concern due to expanding human populations. 
It is currently unknown whether anthropogenic effects of development 
and urbanization are likely to impact the longsolid or round hickorynut 
at the individual or population level. However, secondary impacts such 
as the increased likelihood of potential contaminant introduction, 
stream disturbance caused by impervious surfaces, barrier construction, 
and forest conversion are likely to act cumulatively on longsolid and 
round hickorynut populations.
    Agricultural activities are pervasive across the range of the 
longsolid and round hickorynut. Examples include (but are not limited 
to):
     Longsolid: Agricultural erosion is listed among the 
factors affecting the Clinch and Powell Rivers (Ahlstedt et al. 2016, 
p. 8).
     Longsolid: Sedimentation and other non-point source 
pollution, primarily of agricultural origin, are identified as a 
primary threat to aquatic fauna of the Nolichucky River (Tennessee 
Valley Authority (TVA) 2006, p. 11).
     Longsolid: Agricultural impacts have been noted to take a 
toll on mussel fauna in the Goose Creek watershed of the South Fork 
Kentucky River (Evans 2010, p. 15).
     Longsolid and round hickorynut: The Elk River in Tennessee 
is a watershed with significant agricultural activity (Woodside et al. 
2004, p. 10).
     Round hickorynut: Water withdrawals for irrigation for 
agricultural uses have increased recently in the Tippecanoe River 
(Fisher 2019, pers. comm.).
     Round hickorynut: Sedimentation and other point and non-
point source pollution, primarily of agricultural origin, are 
identified as a primary threat to aquatic fauna of Big Darby Creek and 
Killbuck Creek, Ohio (Ohio Department of the Environmental Protection 
Agency 2004, p. 1; Ohio Department of the Environmental Protection 
Agency 2011, p. 31).
     Round hickorynut: Approximately 25 percent of the land use 
area in the

[[Page 14804]]

West Fork River management unit in West Virginia is in agriculture, 
increasing by as much as 9 percent as most recently reported in 2010 
(U.S. Department of Agriculture 2010, p. 8).
     Round hickorynut: Large-scale mechanized agricultural 
practices threaten the last remaining population in the Lower 
Mississippi River basin, in the Big Black River, where the species has 
already undergone range reduction (Peacock and James 2002, p. 123).
     Round hickorynut: The Duck, Buffalo, and Elk Rivers in 
Tennessee are watersheds with significant agricultural activity in 
their headwaters and tributaries and are a suspected cause for mussel 
community declines throughout those rivers (Reed 2014, p. 4).

Transportation

    Transportation-related impacts include both road development and 
river navigation. By its nature, road development increases impervious 
surfaces as well as land clearing and habitat fragmentation. Roads are 
generally associated with negative effects on the biotic integrity of 
aquatic ecosystems, including changes in surface water temperatures and 
patterns of runoff, changes in sedimentation levels, and increased 
heavy metals (especially lead), salts, organics, and nutrients to 
stream systems (Trombulak and Frissell 2000, p. 18). The adding of 
salts through road de-icing results in high salinity runoff, which is 
toxic to freshwater mussels. In addition, a major impact of road 
development is improperly constructed culverts at stream crossings, 
which can act as barriers if flow through the culvert varies 
significantly from the rest of the stream, or if the culvert ends up 
becoming perched (i.e., sitting above the downstream streambed), and 
fishes that serve as mussel hosts cannot pass through them.
    With regard to river navigation, dredging and channelization 
activities (as a means of maintaining waterways) have altered riverine 
habitats nationwide (Ebert 1993, p. 157). Channelization affects many 
physical characteristics of streams through accelerated erosion, 
increased bed load, reduced depth, decreased habitat diversity, 
geomorphic instability, and riparian canopy loss (Hartfield 1993, p. 
139). All of these impacts contribute to loss of habitat for the 
longsolid and round hickorynut and alter habitats for host fish. 
Changes in both the water velocity and deposition of sediments not only 
alters physical habitat, but the associated increases in turbulence, 
suspended sediment, and turbidity affect mussel feeding and respiration 
(Aldridge et al. 1987, p. 25). The scope of channel maintenance 
activities over extensive areas alters physical habitat and degrades 
water quality. In addition to dredging and channel maintenance, impacts 
associated with barge traffic, which includes construction of fleeting 
areas, mooring cells, docking facilities, and propeller wash, also 
destroy and disrupt mussel habitat (see Miller et al. (1989, pp. 48-49) 
as an example for disturbance from barges).
    Transportation-related impacts across the range of the longsolid 
and round hickorynut include (but are not limited to) the following 
examples:
     Channelization and dredging--Longsolid populations in the 
Eel, Vermilion, and Embarras Rivers and Killbuck Creek are extirpated. 
Round hickorynut populations in the Vermilion and Embarras Rivers are 
extirpated, while populations in the Eel and Killbuck Creek management 
units are in low condition; these streams have been extensively dredged 
and channelized (Butler 2007, p. 63; Appendix B). Additionally, 
dredging for barge traffic and navigation is identified as the primary 
cause for suitable habitat loss in the Kanawha River (below river mile 
79) in West Virginia (Taylor 1983b, p. 3).
     Barge traffic, which includes construction of fleeting 
areas, mooring cells, docking facilities, and propeller wash, destroys 
and disrupts mussel habitat, currently affecting at least 15 (25 
percent) of the longsolid populations in the Ohio, Cumberland, and 
Tennessee River basins (Hubbs et al. 2006, p. 169; Hubbs 2012, p. 3; 
Smith and Meyer 2010, p. 555; Sickel and Burnett 2005, p. 7; Taylor 
1983b, p. 5). All six of the Ohio River mainstem longsolid populations 
that are considered in low condition are affected by channel 
maintenance and navigation operations; at least five (8 percent) of the 
round hickorynut populations in the Ohio basin are affected.
     Channel maintenance and navigation are affecting the low 
condition populations in the lower Allegheny, Kanawha, and Tennessee 
Rivers due to their clustered distribution and proximity to locks and 
dams. For the longsolid, these include two Allegheny River populations 
below Redbank, Pennsylvania (Smith and Meyer 2010, p. 556); one 
population in the Kanawha River, West Virginia; and three low condition 
populations in the Tennessee River main stem above Kentucky Dam.
     Although most prevalent on the mainstem Ohio and Tennessee 
Rivers, commerce and commercial navigation currently affect round 
hickorynut populations in the Black and Muskingum Rivers.

Contaminants

    Contaminants contained in point and non-point discharges can 
degrade water and substrate quality and adversely impact mussel 
populations. Although chemical spills and other point sources of 
contaminants may directly result in mussel mortality, widespread 
decreases in density and diversity may result in part from the subtle, 
pervasive effects of chronic, low-level contamination (Naimo 1995, p. 
354). The effects of heavy metals, ammonia, and other contaminants on 
freshwater mussels were reviewed by Mellinger (1972), Fuller (1974), 
Havlik and Marking (1987), Naimo (1995), Keller and Lydy (1997), and 
Newton et al. (2003).
    The effects of contaminants such as metals, chlorine, and ammonia 
are profound on juvenile mussels (Augspurger et al. 2003, p. 2,571; 
Bartsch et al. 2003, p. 2,566). Juvenile mussels may readily ingest 
contaminants adsorbed to sediment particles while pedal feeding (Newton 
and Cope 2007, p. 276). These contaminants also affect mussel 
glochidia, which are sensitive to some toxicants (Goudreau et al. 1993, 
p. 221; Jacobson et al. 1997, p. 2,386; Valenti et al. 2005, p. 1,243).
    Mussels are noticeably intolerant of heavy metals (Havlik and 
Marking 1987, p. 4). Even at low levels, certain heavy metals may 
inhibit glochidial attachment to fish hosts. Cadmium appears to be the 
heavy metal most toxic to mussels (Havlik and Marking 1987, pp. 4-9), 
although chromium, copper, mercury, and zinc also negatively affect 
biological processes (Naimo 1995, p. 355; Jacobson et al. 1997, p. 
2,389; Valenti et al. 2005, p. 1,243). Chronic mercury contamination 
from a chemical plant on the North Fork Holston River, Virginia, 
destroyed a diverse mussel fauna downstream of Saltville, Virginia, and 
potentially contributed to the extirpation of the longsolid from that 
river (Brown et al. 2005, p. 1,459). An example of long-term declines 
and extirpation of mussels attributed to copper and zinc contamination 
originating from wastewater discharges at electric power plants 
includes the Clinch River in Virginia (a portion of which the longsolid 
currently occupies) (Zipper et al. 2014, p. 9). This highlights that, 
despite localized improvements, these metals can stay bound in 
sediments, affecting recruitment and densities of the mussel fauna for 
decades (Price et al. 2014, p. 12; Zipper et al. 2014, p. 9).

[[Page 14805]]

    Examples of contaminant-related impacts across the range of 
longsolid and/or round hickorynut include (but are not limited to):
     Contaminants have affected mussel glochidia on the Clinch 
River, which is a stronghold population for the longsolid (Goudreau et 
al. 1993, p. 221; Jacobson et al. 1997, p. 2,386; Valenti et al. 2005, 
p. 1,243); round hickorynut is now considered extirpated in the 
Tennessee section of the river.
     The toxic effects of high salinity wastewater from oil and 
natural gas drilling on juvenile and adult freshwater mussels were 
observed in the Allegheny River, Pennsylvania, and in the Ohio River 
basin (Patnode et al. 2015, p. 55).
     Numerous streams throughout both species' ranges have 
experienced mussel and fish kills from toxic chemical spills, such as 
Fish Creek in Indiana for the round hickorynut (Sparks et al. 1999, p. 
12), and the upper Tennessee River system in Virginia for the longsolid 
(Ahlstedt et al. 2016, p. 8; Neves 1987, p. 9; Jones et al. 2001, p. 
20; Schmerfeld 2006, p. 12). Also in the Tennessee River basin, high 
counts of coliform bacteria originating from wastewater treatment 
plants have been documented, contributing to degradation of water 
quality being a primary threat to aquatic fauna (Neves and Angermeier 
1990, p. 50).
     Heavy metals and their toxicity to mussels have been 
documented in the Great Lakes and in the Clinton, Muskingum, Ohio, Fox, 
Powell, Clinch, and Tennessee Rivers where one or both of these species 
occur (Havlik and Marking 1987, pp. 4-9; van Hees et al. 2010, p. 606). 
Coal plants are also located on the Kanawha, Green, and Cumberland 
Rivers, and the effects of these facilities on water quality and the 
freshwater mussel fauna, including the longsolid and round hickorynut, 
are likely similar.
    The degradation of water quality as a result of land-based oil and 
gas drilling activities has a significant adverse effect on freshwater 
mussels, and specifically on the longsolid in the Ohio River basin and 
populations in the Allegheny River, as well as the Kanawha, Little 
Kanawha, and Elk Rivers (Entrekin et al. 2015, p. 2; Ecological 
Specialists, Inc. 2009, p. 27; Pond et al. 2008, p. 723; Patnode et al. 
2015, p. 55).

Agricultural Activities

    The advent of intensive row crop agricultural practices has been 
cited as a potential factor in freshwater mussel decline and species 
extirpation in the eastern United States (Peacock et al. 2005, p. 550). 
Nutrient enrichment and water withdrawals, which are threats commonly 
associated with agricultural activities, are most likely to affect 
individual longsolid and round hickorynut mussels, although in some 
instances may be localized and limited in scope. However, chemical 
control using pesticides, including herbicides, fungicides, 
insecticides, and their surfactants and adjuvants, are highly toxic to 
juvenile and adult freshwater mussels (Bringolf et al. 2007, p. 2,092). 
Waste from confined animal feeding and commercial livestock operations 
is another potential source of contaminants that comes from 
agricultural runoff. The concentrations of these contaminants that 
emanate from fields or pastures may be at levels that can affect an 
entire population, especially given the highly fragmented distributions 
of the longsolid and round hickorynut (also see Contaminants, above).
    Agencies such as the U.S. Department of Agriculture's Natural 
Resources Conservation Service and Soil and Water Conservation 
Districts provide technical and financial assistance to farmers and 
private landowners. Additionally, county resource development councils 
and university agricultural extension services disseminate information 
on the importance of minimizing land use impacts, specifically 
agriculture, on aquatic resources. These programs help identify 
opportunities for conservation through projects such as exclusion 
fencing and alternate water supply sources, which help decrease 
nutrient inputs and water withdrawals, and help keep livestock off of 
stream banks and shorelines, thus reducing erosion. However, the 
overall effectiveness of these programs over a large scale is unknown 
given the longsolid's and round hickorynut's wide distribution and 
varying agricultural intensities.
    Given the large extent of private land and agricultural activities 
within the ranges of the longsolid and round hickorynut, the effects of 
agricultural activities that degrade water quality and result in 
habitat deterioration (also see Development/Urbanization, above) are 
not frequently detected until after the event(s) occur. In summary, 
agricultural activities are pervasive across the ranges of the 
longsolid and round hickorynut. The effects of agricultural activities 
on the longsolid and round hickorynut are a factor in their historical 
decline and localized extirpations.
    Agricultural activities are pervasive across the range of the 
longsolid and round hickorynut. Specifically, agricultural impacts have 
affected and continue to affect high, medium, and low condition 
longsolid populations within these basins, including:
     Longsolid only: French Creek and Allegheny River 
(Pennsylvania), Hughes River (West Virginia), Tuscawaras River (Ohio), 
Rolling Fork River (Kentucky), Little River and Valley River (North 
Carolina), Nolichucky River (Tennessee), Clinch and Powell Rivers 
(Tennessee and Virginia), and Estill Fork (Alabama).
     Round hickorynut only: South Fork Hughes River (West 
Virginia), and Pine, Belle, and Black Rivers (Michigan).
     Both species: Shenango River (Pennsylvania); Middle Island 
Creek, Elk, Little Kanawha, and North Fork Hughes Rivers (West 
Virginia); Licking and Kentucky Rivers (Kentucky); Elk and Buffalo 
Rivers (Tennessee); and Paint Rock River (Alabama).

Dams and Barriers

    The effects of impoundments and barriers on aquatic habitats and 
freshwater mussels are relatively well-documented (Watters 2000, p. 
261). Dams alter and disrupt connectivity, and alter water quality, 
which affect longsolid and round hickorynut species. Extinction/
extirpation of North American freshwater mussels can be traced to 
impoundment and inundation of riffle habitats in all major river basins 
of the central and eastern United States (Haag 2009, p. 107). Humans 
have constructed dams for a variety of reasons: flood prevention, water 
storage, electricity generation, irrigation, recreation, and navigation 
(Eissa and Zaki 2011, p. 253). Dams, either natural (by beavers or by 
aggregations of woody debris) or manmade, have many impacts on stream 
ecosystems. Reductions in the diversity and abundance of mussels are 
primarily attributed to habitat shifts caused by impoundments (Neves et 
al. 1997, p. 63). The survival of mussels and their overall 
reproductive success are influenced:
     Upstream of dams, by the change from flowing to impounded 
waters, increased depths, increased buildup of sediments, decreased 
dissolved oxygen, and the drastic alteration in resident fish 
populations.
     Downstream of dams, by fluctuations in flow regimes, 
minimal releases and scouring flows, seasonal depletion of dissolved 
oxygen, reduced or increased water temperatures, and changes in fish 
assemblages.
    Additionally, improperly constructed culverts at stream crossings 
may act as barriers and have some similar negative effects as dams on 
stream systems. Fluctuating flows through the culvert can vary 
significantly from the rest of the stream, preventing fish passage and

[[Page 14806]]

scouring downstream habitats. For example, if a culvert sits above the 
streambed, aquatic organisms cannot pass through it. These barriers 
fragment habitats along a stream course and contribute to genetic 
isolation of the aquatic species inhabiting the streams.
    Whether constructed for purposes such as flood control, navigation, 
hydropower, water supply or multi-purpose uses, the construction and 
continued operation of dams (per existing licensing schedules) is a 
pervasive negative influence on the longsolid, round hickorynut, and 
their habitats throughout their ranges. Although there are recent 
efforts to remove older, failing dams within the ranges of the 
longsolid and round hickorynut, such as Lock and Dam 6 on the Green 
River, and Six Mile Dam on the Walhonding River, dams and their effects 
on longsolid and round hickorynut population distributions have had 
perhaps the greatest documented negative influence on these species 
(Hardison and Layzer 2001, p. 79; Layzer et al. 1993, p. 68; Parmalee 
and Polhemus 2004, p. 239; Smith and Meyer 2010, p. 543; Hubbs 2012, p. 
8; Watters and Flaute 2010, p. 2).
    Over 20 of the rivers and streams currently occupied by the 
longsolid are directly affected by dams, thus directly influencing the 
species' distribution rangewide. For the round hickorynut, all occupied 
rivers and streams are directly or indirectly affected by dams. See 
section 6.1.5 of the SSA reports for specific areas where dams and 
other impoundments occur within the range of the species (Service 2018, 
pp. 59-63; Service 2019, pp. 73-77).

Changing Climate Conditions

    Changing climate conditions that can influence freshwater mussels 
include increasing or decreasing water temperatures and precipitation 
patterns that result in increased flooding, prolonged droughts, or 
reduced stream flows, as well as changes in salinity levels (Nobles and 
Zhang 2011, pp. 147-148). An increase in the number of days with heavy 
precipitation over the next 25 to 35 years is expected across the 
longsolid's range (U.S. Global Climate Change Research Program 2017, p. 
207). Although changing climate conditions have potentially affected 
the longsolid, the timing, frequency, and extent of these effects is 
currently unknown. Possible impacts to the species could include 
alteration of the fundamental ecological processes, such as thermal 
suitability; changes in seasonal patterns of precipitation and runoff, 
which could alter the hydrology of streams; and changes in the presence 
or combinations of invasive, native or nonnative species.
    We examined information on anticipated climate effects to wide-
ranging mussels, which included a study that used representative 
concentration pathways (RCPs) 2.6 and 8.5 and was conducted on the 
federally endangered spectaclecase (Cumberlandia monodonta). Our 
analysis of the best available climate change information revealed that 
within the range of both the longsolid and round hickorynut, shifts in 
the species-specific physiological thresholds in response to altered 
precipitation patterns and resulting thermal regimes are possible. 
Additionally, the expansion of invasive, nonnative species because of 
climatic changes has the potential for long-term detriments to the 
mussels and their habitats. Other potential impacts are associated with 
changes in food web dynamics and the genetic bottleneck that can occur 
with low effective population sizes (Nobles and Zhang 2011, p. 148). 
The influences of these changes on the longsolid and round hickorynut 
are possible in the future (see Scenario 3 discussions under Future 
Conditions, below). Multi-scale climate models that can be interpreted 
at both the rangewide and population levels, and are tailored to 
benthic invertebrates, which incorporate genetic and life-history 
information, are needed before the longsolid and round hickorynut 
declines can be correlated with climate change. At this time, the best 
available information indicates that climate change is considered a 
secondary factor influencing the viability of the longsolid and round 
hickorynut and is not currently thought to be a primary factor in the 
longsolid's or round hickorynut's occurrence and distribution across 
their ranges.

Resource Extraction

    The most intensive resource extraction activities affecting the 
longsolid, round hickorynut, and their habitats are coal mining and oil 
and gas exploration, which are summarized here. Additional less 
intensive resource extraction activities affecting the species include 
gravel mining/dredging, which is detailed in the SSA reports (Service 
2018, pp. 64-65; Service 2019, pp. 79-83).
    Activities associated with coal mining and oil and gas drilling can 
contribute chemical pollutants to streams. Acid mine and saline 
drainage (AMD) is created from the oxidation of iron-sulfide minerals 
such as pyrite, forming sulfuric acid (Sams and Beer 2000, p. 3). This 
AMD may be associated with high concentrations of aluminum, manganese, 
zinc, and other constituents (Tennessee Department of Environment and 
Conservation (TDEC) 2014, p. 72). These metals, and the high acidity 
typically associated with AMD, can be acutely and chronically toxic to 
aquatic life (Jones 1964, p. 96).
    Natural gas extraction has negatively affected water quality 
through accidental spills and discharges, as well as increased 
sedimentation due to increases in impervious surface and tree removal 
for drill pads and pipelines (Vidic et al. 2013, p. 6). Disposal of 
insufficiently treated brine wastewater is known to adversely affect 
freshwater mussels (Patnode et al. 2015, p. 62). Contaminant spills are 
also a concern.
    Unconsolidated sediment appears to be the largest impact to mussel 
physical habitat in streams as a result of gas extraction activities 
(Entrekin et al. 2015, p. 23). Excessive suspended sediments can impair 
feeding processes, leading to acute short-term or chronic long-term 
stress. Both excessive sedimentation and excessive suspended sediments 
can lead to reduced mussel fitness (Ellis 1936, p. 29; Anderson and 
Kreeger 2010, p. 2). This sediment is generated by construction of the 
well pads, access roads, and pipelines (for both gas and water).
    Examples of the variety of resource extraction activities (coal, 
oil, gas, and gravel mining) that occur across the range of the 
longsolid and round hickorynut include (but are not limited to):
     Longsolid: The Cumberland Plateau and Central Appalachian 
regions of Tennessee and Kentucky (upper Cumberland River system and 
upper Tennessee River system) continue to experience mining activity 
that impairs water quality in streams (TDEC 2014, p. 62).
     Longsolid: High levels of copper, manganese, and zinc, 
metals toxic to freshwater mussels, were found in sediment samples from 
both the Clinch and Powell Rivers, and mining impacts close to Big 
Stone Gap, Virginia, have almost eliminated the mussel fauna in the 
upper Powell River. The longsolid is considered extirpated from the 
South Fork Powell River and Cane Creek, both tributaries to the upper 
portion of the Powell River (Ahlstedt and Tuberville 1997, p. 75; 
appendix D in the SSA report).
     Round hickorynut: Although populations persist in the 
Rockcastle River and Buck Creek in the Cumberland basin, coal and 
gravel mining continue to occur in these watersheds.
     Round hickorynut: The extensive mining of gravel in 
riparian zones

[[Page 14807]]

reduces vegetative buffers and causes channel instability and has been 
implicated in mussel declines in the Walhonding River, Ohio, which 
harbors a low condition population (Hoggarth 1995-96, p. 150).
     Round hickorynut: The West Fork River in West Virginia has 
oil and gas activity within the watershed, as well as legacy mining 
issues, which have resulted in biological impairment throughout the 
drainage (West Virginia Department of Environmental Protection 2014, 
pp. 23-29).
     Both species: Impacts from natural gas pipelines have a 
high potential to occur in West Virginia and Pennsylvania. Tank trucks 
hauling such fluids can overturn into mussel streams, which has 
occurred in Meathouse Fork of Middle Island Creek (Clayton 2018, pers. 
comm.).
     Both species: Natural gas extraction in the Marcellus 
Shale region (the largest natural gas field in the United States that 
runs through northern Appalachia) has negatively affected water quality 
through accidental spills and discharges in populations in the 
Shenango, Elk, Little Kanawha, and Kanawha management units.
     Both species: Coal mining has been implicated in sediment 
and water chemistry impacts in the Kanawha River in West Virginia, 
potentially limiting the Kanawha River populations of both species 
(Morris and Taylor 1978, p. 153).
     Both species: Resource extraction and AMD have been cited 
as contributors to the loss of mussel species in the Cumberland basin 
(Haag and Cicerello 2016, p. 15), including the loss of longsolid from 
Rockcastle and Caney Fork Rivers, and the loss of round hickorynut in 
the Caney Fork, Little South Fork, Big South Fork, and Cumberland 
Rivers (Anderson et al. 1991, p. 6; Layzer and Anderson 1992, p. 97; 
Warren and Haag 2005, p. 1,383).
     Both species: In the upper Kentucky River watershed, where 
both species exhibit a lack of recruitment (and also in the Red River 
for round hickorynut), historical un-reclaimed mines and active coal 
mines are prevalent (Kentucky Department for Environmental Protection 
2015, p. 66).

Forest Conversion

    Clearing large areas of forested wetlands and riparian systems 
eliminates shade once provided by tree canopies, exposing streams to 
more sunlight and increasing the in-stream water temperature (Wenger 
1999, p. 35). The increase in stream temperature and light after 
deforestation alters macroinvertebrate (and other aquatic species) 
richness, abundance, and composition in streams to various degrees 
depending on a species' tolerance to temperature changes and increased 
light in the aquatic system (Kishi et al. 2004, p. 283; Couceiro et al. 
2007, p. 272; Caldwell et al. 2014, p. 2,196).
    Sediment runoff from clearing forested areas is a known stressor to 
aquatic systems (e.g., Webster et al. 1992, p. 232; Jones III et al. 
1999, p. 1,455; Broadmeadow and Nisbet 2004, p. 286; Aust et al. 2011, 
p. 123). The physical characteristics of stream channels are affected 
when large quantities of sediment are added or removed (Watters 2000, 
p. 263). Mussels and fishes are potentially affected by changes in 
suspended and bed material load, changes in bed sediment composition 
associated with increased sediment production and runoff, changes in 
channel formation, stream crossings, and inadequately buffered clear-
cut areas, all of which can be sources of sediment entering streams 
(Taylor et al. 1999, p. 13).
    Forest conversion to other land uses such as agriculture and urban 
development has occurred across the range of the longsolid and round 
hickorynut. Siltation and erosion from forest conversion to other land 
use activities without BMPs is a well-documented stressor to aquatic 
systems throughout the eastern United States, and can have an impact 
depending on the physical, chemical, and biological characteristics of 
adjacent streams (Allan and Castillo 2007, p. 107). Forest conversion 
has been documented in all basins in which these species occur.
    Also, some forestry practices have the potential to result in 
increased siltation in riparian systems through the cycle of forest 
thinning, final harvest, site preparation, and re-planting activities. 
However, implementation of BMPs and establishment of SMZs can minimize 
these impacts (Service 2018 and 2019, chapter 6); adherence to these 
BMPs and SMZs broadly protects water quality, particularly related to 
sedimentation (as reviewed by Cristan et al. 2016, entire; Warrington 
et al. 2017, entire; and Schilling et al. 2021, entire).

Invasive and Nonnative Species

    When a nonnative species is introduced into an ecosystem, it may 
have many advantages over native species, such as easy adaptation to 
varying environments and a high tolerance of living conditions that 
allow it to thrive in its new habitat. There may not be natural 
predators to keep the nonnative species in check; therefore, it can 
potentially live longer and reproduce more often, further reducing the 
biodiversity in the system. The native species may become an easy food 
source for invasive, nonnative species, or the invasive species may 
carry diseases that extirpate populations of native species. Invasive, 
nonnative species are pervasive across the longsolid's and round 
hickorynut's ranges. Examples of invasive, nonnative species that 
affect freshwater mussels like the longsolid and round hickorynut are 
the Asian clam (Corbicula fluminea), zebra mussel (Dreissena 
polymorpha), quagga mussel (Dreissena bugensis), black carp 
(Mylopharyngodon piceus), didymo (also known as rock snot; 
Didymosphenia geminata), and hydrilla (also known as water-thyme; 
Hydrilla verticillata).
     The Asian clam alters benthic substrates, may filter 
mussel sperm or glochidia, competes with native species for limited 
resources, and causes ammonia spikes in surrounding water when they die 
off en masse (Scheller 1997, p. 2).
     Dreissenid mollusks, such as the zebra mussel and quagga 
mussel, adversely affect native species through direct colonization, 
reduction of available habitat, changes in the biotic environment, or a 
reduction in food sources (MacIsaac 1996, p. 292). Zebra mussels are 
also known to alter the nutrient cycle in aquatic habitats, affecting 
other mollusks and fish species (Strayer 1999, p. 22).
     Given their size and diet preferences, black carp have the 
potential to restructure benthic communities. Mussel beds consisting of 
smaller individuals and juvenile recruits are probably most vulnerable 
to being consumed by black carp (Nico et al. 2005, p. 192). 
Furthermore, because black carp attain a large size (well over 3.28-ft 
(1-m) long), and their life span is reportedly over 15 years, they are 
expected to persist for many years. Therefore, they have the potential 
to cause harm to native mollusks by way of predation on multiple age 
classes (Nico et al. 2005, p. 77).
     The two nonnative plant species that are most problematic 
for the longsolid and round hickorynut (i.e., impacting the species 
throughout their ranges) are hydrilla and didymo. Hydrilla is an 
aquatic plant that alters stream habitat, decreases flows, and 
contributes to sediment buildup in streams (National Invasive Species 
Council Management Plan 2018, p. 2). High sedimentation can cause 
suffocation, reduce stream flow, and make it difficult for mussels' 
interactions with host fish necessary for development. Didymo can alter 
the

[[Page 14808]]

habitat and change the flow dynamics of a site (Jackson et al. 2016, p. 
970). Invasive plants grow uncontrolled and can smother habitat, affect 
flow dynamics, alter water chemistry, and increase water temperatures, 
especially in drought conditions (Colle et al. 1987, p. 416).
     Specifically for the round hickorynut, the nonnative round 
goby can out-compete native benthic fishes (such as darters and 
sculpin) for food and other resources, and may also prey especially 
heavily on juvenile native mussels, such as round hickorynut (Bradshaw-
Wilson et al. 2019, p. 268)

Effects Associated With Small Population Size

    Without the level of population connectedness that the species 
experienced historically (i.e., without barriers such as reservoirs), 
small, isolated populations that may now be comprised predominantly of 
adult individuals could be slowly dying out. Even given the very 
improbable absence of other anthropogenic threats, these disjunct 
populations could be lost simply due to the consequences of below-
threshold effective population sizes. Because only 60 primarily 
disjunct streams among 160 historically occupied areas continue to 
harbor populations of the longsolid, and 69 primarily disjunct streams 
of 301 historically occupied areas continue to harbor populations of 
the round hickorynut, this is likely partial testimony to the principle 
of effective population size and its role in population loss.
    The longsolid and round hickorynut exhibit several traits that 
influence population viability, including relatively small population 
size and low fecundity at many locations compared to other mussels (see 
appendix A in Service 2018 and 2019). Small population size puts the 
species at greater risk of extirpation from stochastic events (e.g., 
drought) or anthropomorphic changes and management activities that 
affect habitat. In addition, small longsolid or round hickorynut 
populations may have reduced genetic diversity, be less genetically 
fit, and be more susceptible to disease during extreme environmental 
conditions compared to large populations (Frankham 1996, p. 1,505).
    Genetic drift occurs in all species, but the lack of drift is more 
likely to negatively affect populations that have a smaller effective 
population size (number of breeding individuals) and populations that 
are geographically spread out and isolated from one another. Relatively 
low fecundity, commonly observed in species of Fusconaia, is another 
inherent factor that could influence population viability (Geist 2010, 
p. 91). Survival of juveniles in the wild is already low, and females 
produce fewer offspring than other mussel species (Haag and Staton 
2003, p. 2,125). Factors such as low effective population size, genetic 
isolation, relatively low levels of fecundity and recruitment, and 
limited juvenile survival could all affect the ability of these species 
to maintain current population levels and to rebound if a reduction in 
population occurs (e.g., through predation, toxic releases or spills, 
or poor environmental conditions that inhibit successful reproduction). 
Additionally, based on our presumption of fish hosts of the longsolid 
and the known species of fish hosts for the round hickorynut, they are 
small-bodied fishes that have comparatively limited movement (Vaughn 
2012, p. 6); therefore, natural expansion of longsolid and round 
hickorynut populations is limited.
    Dendritic (branched) streams and rivers are highly susceptible to 
fragmentation and may result in multiple habitat fragments and isolated 
populations of variable size (Fagan 2002, p. 3,247). In contrast to 
landscapes where multiple routes of movement among patches are 
possible, pollution or other habitat degradation at specific points in 
dendritic landscapes can completely isolate portions of the system 
(Fagan 2002, p. 3,246).

Future Conditions

    In the SSA reports, we forecast the longsolid's and round 
hickorynut's response to plausible future scenarios of environmental 
conditions and conservation efforts. The future scenarios project the 
threats into the future and consider the impacts those threats could 
have on the viability of the longsolid and round hickorynut. We apply 
the concepts of resiliency, redundancy, and representation to the 
future scenarios to describe possible future conditions of the 
longsolid and round hickorynut. The scenarios described in the SSA 
reports represent only three possible future conditions for each of the 
species. Uncertainty is inherent in any risk assessment, so we must 
consider plausible conditions to make our determinations. Viability is 
not a specific state, but rather a continuous measure of the likelihood 
that the species will sustain populations over time.
    In the SSA reports, we considered three future scenarios. Scenario 
1 assesses the species' response to factors influencing current 
longsolid and round hickorynut populations and management units, 
assuming the current level of impacts remains constant into the future. 
Scenario 2 assesses the species' response when factors that negatively 
influence most of the extant populations and management units are 
reduced by additional conservation. Scenario 3 assesses the species' 
response to worsening conditions of the factors that most influence the 
species due to the implementation of known existing and projected 
development, resource extraction, hydroelectric projects, etc. An 
important assumption of the predictive analysis presented herein is 
that future population resiliency for each species is largely dependent 
on water quality, water flow, instream habitat conditions, and 
condition of riparian vegetation (see Species Needs, above).
    The future conditions timeframe for our analysis is different for 
each species. A timeframe of 50 to 70 years into the future is 
evaluated for the longsolid, and 20 to 30 years into the future is 
evaluated for the round hickorynut. We selected these timeframes based 
on the availability of trends and threat information, planning 
documents, and climate modeling that could be reliably projected into 
the future, and also the consideration of at least two generations for 
each species (i.e., 25 to 35 years for the long-lived longsolid, and on 
average 12-13 years (Shepard 2006, p. 7; Ehlo and Layzer 2014, p. 11) 
for the round hickorynut).
Longsolid
    Our assessment predicts that if conditions remain the same or 
worsen into the future, all 60 populations would experience negative 
changes to the species' important habitat requisites (see Species 
Needs, above), including the loss of the single remaining population in 
the Cumberland River basin, and potentially resulting in no highly 
resilient populations (Scenario 3). Alternatively, the scenario that 
incorporates additive conservation measures beyond those currently 
implemented (Scenario 2) could result in the continued persistence of 
all 60 populations in the future. However, we note that approximately 
30 of 60 (50 percent) of these are currently low condition populations, 
based on either surveys that pre-date 2000 or on the collection of only 
five or fewer older, non-reproducing individuals. Some of these 
populations may already be extirpated. The risks facing the longsolid 
populations varied among scenarios and are summarized below

[[Page 14809]]

(see table 8-1 and table ES-1 in the SSA report).
    Under Scenario 1, lowered resiliency, representation, and 
redundancy are expected. Under this scenario, we predict that 1 
population of the current 3 high condition populations would remain in 
high condition, 6 populations (10 percent) in medium condition, and 15 
populations (25 percent) in low condition. Redundancy would be reduced 
with likely extirpation of 38 out of 60 (63 percent) currently extant 
populations; only the Ohio River basin (one of the three basins 
currently occupied by the species) would retain one highly resilient 
population (i.e., the Green River population in the Upper Green 
management unit). Representation would be reduced, with two of the 
three currently occupied river basins continuing to harbor longsolid 
populations.
    Under Scenario 2, we predict higher levels of resiliency in some 
areas of the longsolid's range than was estimated for Scenario 1; 
representation and redundancy would remain the same level as current 
conditions, with the species continuing to occur within all currently 
occupied management units and States across its range. Seven 
populations (12 percent) are predicted to be in high condition, 
compared to the current four populations in high condition. Scenario 2 
also predicts 20 populations (33 percent) in medium condition and 33 
populations (52 percent) in low condition; no populations would become 
extirpated. All three currently occupied major river basins would 
remain occupied, and the existing levels of redundancy and 
representation would improve. It is possible that this scenario is the 
least likely to occur in the future as compared to Scenario 1 or 3 only 
because it will take many years (potentially beyond the 50- to 70-year 
timeframe analyzed in the SSA report) for all of the beneficial effects 
of management actions that are necessary to be implemented and realized 
on the landscape.
    Under Scenario 3, we predict a significant decrease in resiliency, 
representation, and redundancy across the species' range. Redundancy 
would be reduced from three major river basins to two basins with no 
high condition populations remaining, and the likely extirpation of 44 
(73 percent) of the currently extant populations. The resiliency of the 
remaining 16 populations is expected to be reduced to 3 populations (5 
percent) in medium condition and 13 (22 percent) in low condition. In 
addition to the loss of 44 populations, 32 (29 percent) of the 
management units are predicted to become extirpated. Representation 
would be reduced to 13 management units, 2 major river basins, and 3 
States (as compared to the current 9 States) occupied by the species.
Round Hickorynut
    Our assessment predicts that if conditions remain the same 
(Scenario 1), 44 of 69 populations (62 percent) would experience 
negative changes to the important habitat requisites, including the 
potential loss of 23 populations. This includes the predicted 
extirpation of the two populations in the Cumberland River basin and 
the population in the Lower Mississippi River basin. Additionally, 
under Scenario 3, no highly resilient populations are able to persist, 
and 90 percent of remaining populations are in low condition. 
Alternatively, the scenario that includes additive conservation 
measures beyond those currently implemented (Scenario 2) could result 
in the continued persistence of all 69 populations in the future. 
However, approximately 49 of 69 (71 percent) of these populations are 
currently in low condition. Many of the known populations of the round 
hickorynut have been collected as 10 or fewer individuals, with limited 
extent information available, due to the lack of survey effort 
targeting the species (Service 2019, appendix A). The risks facing 
round hickorynut populations varied among scenarios and are summarized 
below (see also table 8-1 and table ES-1 in the SSA report).
    Under Scenario 1, lowered resiliency, representation, and 
redundancy are expected. We predict that only one of the current four 
high condition populations would remain in high condition. Under this 
scenario, only the Great Lakes basin (one of the five basins currently 
occupied by the species) would retain a highly resilient population 
(i.e., the Grand River). Of the 69 extant populations, 14 (20 percent) 
would be in medium condition and 31 (45 percent) would be in low 
condition. We estimate extirpation of 23 out of 69 (33 percent) 
populations. Redundancy would decline due to these population and 
management unit losses, resulting in a loss of the species from 
Pennsylvania and Mississippi. Representation would be reduced through 
extirpation of populations and management units in the Cumberland and 
Great Lakes basins, a 40 percent loss of redundancy compared to current 
conditions. Under this scenario, only three of the five currently 
occupied river basins (Great Lakes, Ohio, and Tennessee) continue to 
harbor round hickorynut populations.
    Under Scenario 2, we predict higher levels of resiliency in some 
areas of the round hickorynut's range than is estimated for Scenario 1; 
representation and redundancy would remain the same level as current 
conditions with the species continuing to occur within all currently 
occupied management units and States across the species' 9-State range. 
Up to 15 populations (23 percent) are predicted to be high condition 
compared to the current 4 populations in high condition. Scenario 2 
also predicts 39 populations (56 percent) in medium condition and 15 
populations (22 percent) in low condition. All currently occupied major 
river basins would remain occupied, and the existing levels of 
redundancy and representation would improve. There are sufficient 
population sizes within each basin to facilitate augmentation and 
restoration efforts, whether it be within-basin translocations or 
captive propagation techniques. It is possible that this scenario is 
the least likely to occur in the future as compared to Scenario 1 or 3. 
This is because it will take many years (potentially beyond the 20- to 
30-year time frame analyzed in the SSA report) for all of the 
beneficial effects of management actions that are necessary to be 
implemented on the landscape to be realized.
    Under Scenario 3, we predict a significant decrease in resiliency, 
representation, and redundancy across the species' range. Redundancy 
would be reduced from five major river basins to three basins, with 
extirpations expected to occur in the Cumberland and Lower Mississippi 
River basins. No high condition populations would remain, and 49 (71 
percent) of the 69 extant populations are likely to become extirpated. 
The resiliency of the remaining 20 populations is expected to be 
reduced to 2 populations (10 percent) in medium condition and 18 (90 
percent) in low condition. In addition to the potential loss of 49 
populations, 23 (68 percent) of the currently extant 36 management 
units are predicted to no longer harbor the species. Representation 
could be reduced to 14 management units across 3 major river basins. 
Extirpations are expected from the States of Pennsylvania, Michigan, 
and Mississippi, leaving 6 States (as compared to the current 9, and 
historically 12) occupied by the species.

Determination of Status for the Longsolid and Round Hickorynut

Introduction

    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures

[[Page 14810]]

for determining whether a species meets the definition of an endangered 
species or a threatened species. The Act defines an ``endangered 
species'' as a species in danger of extinction throughout all or a 
significant portion of its range, and a ``threatened species'' as a 
species likely to become an endangered species within the foreseeable 
future throughout all or a significant portion of its range. The Act 
requires that we determine whether a species meets the definition of 
endangered species or threatened species because of any of the 
following factors: (A) The present or threatened destruction, 
modification, or curtailment of its habitat or range; (B) 
Overutilization for commercial, recreational, scientific, or 
educational purposes; (C) Disease or predation; (D) The inadequacy of 
existing regulatory mechanisms; or (E) Other natural or manmade factors 
affecting its continued existence.
    In conducting our status assessment of the longsolid and round 
hickorynut, we evaluated all identified threats under the Act's section 
4(a)(1) factors and assessed how the cumulative impact of all threats 
acts on the viability of the species as a whole. That is, all the 
anticipated effects from both habitat-based and direct mortality-based 
threats are examined in total and then evaluated in the context of what 
those combined negative effects will mean to the current and future 
condition of the longsolid and round hickorynut. However, for the vast 
majority of potential threats, the effect on the longsolid and round 
hickorynut (e.g., total losses of individual mussels or their habitat) 
cannot be quantified with available information. Instead, we use the 
best available information to gauge the magnitude of each individual 
threat on the longsolid and round hickorynut, and then assess how those 
effects combined (and as may be ameliorated by any existing regulatory 
mechanisms or conservation efforts) will impact the longsolid's or 
round hickorynut's current and future viability.

Longsolid--Status Throughout All of Its Range

    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the section 4(a)(1) factors, we 
determined that the species' distribution and abundance has been 
reduced across its range as demonstrated by both the number of occupied 
management units and the number of populations where it historically 
occurred. Historically, the species occurred within 160 populations and 
105 management units across 12 States; currently, the species occurs in 
60 populations and 45 management units across 9 States, which 
represents a 62 percent reduction of its historically occupied 
populations (although we note that the remaining populations are well-
distributed as opposed to concentrated within its range). The 
conditions of the remaining 60 extant populations vary between being 
highly resilient, moderately resilient, or having low resiliency (see 
Current Conditions, above, and section 5.2 in the SSA report (Service 
2018, pp. 34-37)).
    Currently, 3 populations (5 percent) are highly resilient, 8 (13 
percent) are moderately resilient, and 49 (71 percent) have low 
resiliency. Although downward trends are evident compared to historical 
information, 11 highly to moderately resilient populations are present 
within three of the four major river basins the species is historically 
known to occupy. Current and ongoing threats from habitat degradation 
or loss (Factor A), residual impacts from past harvest and 
overutilization (Factor B), and invasive, nonnative species (Factor E) 
contribute to the species' negative effects associated with small 
population size (Factor E). The continued occupancy of these 11 
populations (in addition to some survey information) implies that 
recent recruitment is occurring in some populations to help maintain a 
level of resiliency, redundancy, and representation. Thus, after 
assessing the best available information, we conclude that the 
longsolid is not currently in danger of extinction throughout all of 
its range. Therefore, we proceed with determining whether the longsolid 
is likely to become an endangered species within the foreseeable future 
throughout all of its range.
    At this point in time, and as noted above, the threats currently 
acting on the species include habitat degradation or loss from a 
variety of sources and invasive, nonnative species, all of which 
contribute to the negative effects associated with the species' small 
population size. Our analysis revealed that these threats are likely to 
continue into the foreseeable future, or approximately 50 to 70 years. 
This timeframe accounts for reasonable predictions of threats 
continuing into the future based on our examination of empirical data 
available over the last 30 years (e.g., survey data, how threats are 
manifesting themselves on the landscape and the species, implementation 
of management plans and voluntary conservation actions), and also takes 
into consideration the biology of the species (multiple generations of 
a long-lived species) and the licensing schedules of dams within the 
species' range.
    The best available information, including our consideration of 
comments we received on the September 29, 2020 (85 FR 61384), proposed 
rule, indicates that the threats currently acting upon the longsolid 
are expected to continue into the foreseeable future, some of which 
(e.g., water quality and habitat degradation, and invasive, nonnative 
species) are reasonably expected to worsen over time, including 
concurrent with increasing human population trends that further reduce 
the species' resiliency, redundancy, and representation across its 
range. Our analysis reveals the potential for either none or a single 
population (i.e., the Green River in Kentucky) to persist as highly 
resilient (i.e., continued reproduction with varied age classes 
present) in the foreseeable future, assuming threats remain or worsen 
on the landscape. Additionally, the majority of the remaining 
populations would exhibit low resiliency, while many (between 30 and 73 
percent of the current low condition populations) would potentially 
become extinct or functionally extinct (e.g., significant habitat 
degradation; no reproduction due to highly isolated, non-recruiting 
individuals). Our future analysis also reveals a high risk that the 
species would become extirpated in one of the four historically 
occupied river basins (i.e., Cumberland River basin); it has already 
been lost from the Great Lakes basin. Thus, after assessing the best 
available information, we conclude that the longsolid is not currently 
in danger of extinction but is likely to become in danger of extinction 
within the foreseeable future throughout all of its range.

Longsolid--Status Throughout a Significant Portion of Its Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. The court in Center for Biological Diversity v. Everson, 435 
F. Supp. 3d 69 (D.D.C. 2020) (Everson), vacated the aspect of the Final 
Policy on Interpretation of the Phrase ``Significant Portion of Its 
Range'' in the Endangered Species Act's Definitions of ``Endangered 
Species'' and ``Threatened Species'' (Final Policy; 79 FR 37578; July 
1, 2014) that provided that the Service does not undertake an analysis 
of significant portions of a species' range if the species warrants 
listing as threatened throughout all of its range.

[[Page 14811]]

    Therefore, we proceed to evaluating whether the species is 
endangered in a significant portion of its range--that is, whether 
there is any portion of the species' range for which both (1) the 
portion is significant; and (2) the species is in danger of extinction 
in that portion. Depending on the case, it might be more efficient for 
us to address the ``significance'' question or the ``status'' question 
first. We can choose to address either question first. Regardless of 
which question we address first, if we reach a negative answer with 
respect to the first question that we address, we do not need to 
evaluate the other question for that portion of the species' range.
    Following the court's holding in Everson, we now consider whether 
there are any significant portions of the species' range where the 
species is in danger of extinction now (i.e., endangered). In 
undertaking this analysis for the longsolid, we choose to address the 
status question first--we consider information pertaining to the 
geographic distribution of both the species and the threats that the 
species faces to identify portions of the range where the species may 
be in danger of extinction.
    We evaluated the range of the longsolid to determine if the species 
is in danger of extinction now in any portion of its range. The range 
of a species can theoretically be divided into portions in an infinite 
number of ways. We examined the species entire range in an attempt to 
focus this analysis on portions of the species' range that may meet the 
definition of an endangered species. For the longsolid, we considered 
whether the threats or their effects on the species are greater in any 
biologically meaningful portion of the species' range than in other 
portions such that the species is in danger of extinction now in that 
portion.
    The statutory difference between an endangered species and a 
threatened species is the timeframe in which the species becomes in 
danger of extinction; an endangered species is in danger of extinction 
now while a threatened species is not in danger of extinction now but 
is likely to become so in the foreseeable future. Thus, we considered 
the time horizon for the threats that are driving the longsolid to 
warrant listing as a threatened species throughout all of its range. We 
then considered whether these threats or their effects are occurring in 
any portion of the species' range such that the species is in danger of 
extinction now in that portion of its range. We examined the following 
threats: habitat degradation or loss; invasive, nonnative species; 
effects associated with small population size; and the potential for 
cumulative effects. We also considered whether these threats may be 
exacerbated by small population size (or low condition). Overall, we 
found that threats are likely acting on individuals or populations, or 
even basins, similarly across the species' range. These threats are 
certain to occur, and in those basins with few populations that are 
predominantly in low condition, these populations are facing the same 
threats, and these threats can be of greater magnitude in some areas or 
of greater impact, given small population sizes.
    One basin--the Cumberland River--has been reduced by 91 percent 
with one remaining low condition population. Although there are low 
condition populations in all three basins in which the species occurs, 
because this basin has seen its populations significantly reduced to a 
single population currently in low condition, this circumstance--in 
combination with the other threats acting on the species throughout its 
range--may indicate that the species may be in danger of extinction now 
in this portion of the range.
    Small, isolated populations often exhibit reduced levels of genetic 
variability, which diminishes the species' capacity to adapt and 
respond to environmental changes, thereby decreasing the probability of 
long-term persistence. Small populations may experience reduced 
reproductive vigor, for example, due to inbreeding depression. Isolated 
individuals may have difficulty reproducing. The problems associated 
with small population size and vulnerability to random demographic 
fluctuations or natural catastrophes are further magnified by 
synergistic interactions with other threats, such as those discussed 
above. Based on our review of information and the synergistic effects 
of threats exacerbated by a single low-condition population in the 
Cumberland River basin, we find that this basin is a portion of the 
longsolid's range with a potential difference in biological condition.
    Because we have determined the Cumberland River basin is a portion 
of the range that may be in danger of extinction now, we next evaluate 
whether this portion may be significant. We first examined this area's 
contribution to the resiliency, redundancy, and representation of the 
species. We determined that this basin contains 1 of 60 populations 
(1.7 percent) identified in the SSA report. Therefore, this single 
population does not contribute significantly, either currently or in 
the foreseeable future, to the species' total resiliency at a 
biologically meaningful scale compared to other representative areas. 
The overall representation described herein would likely be the same 
under two of the three scenarios. We conclude that the Cumberland River 
basin population does not contribute meaningfully to the species' 
viability overall. We evaluated the best available information for the 
Cumberland River basin in this context, assessing its significance in 
terms of these conservation concepts and determined that this single 
portion is not biologically significant to the species.
    The single population in the Cumberland River basin does not act as 
a refugia for the species or as an important spawning ground. In 
addition, the water quality is similar throughout the species' range 
with impaired water quality occurring in all three basins. Since the 
longsolid occurs in similar aquatic habitats across its range, the 
Cumberland River basin portion provides similar habitat characteristics 
as the remainder of the range. Therefore, there are no unique habitat 
characteristics attributable to just the Cumberland River basin portion 
of the range, and this portion serves a similar role in supporting the 
species' viability as compared to the rest of the range.
    Overall, and in summary, we found one portion of the longsolid's 
range, the Cumberland River basin, that may have a different status as 
compared to the remaining portion of the longsolid's range. We found 
the Cumberland River basin was not a biologically meaningful portion of 
the longsolid's range; in other words, we found it was not significant 
in terms of its overall contribution to the species' resiliency, 
redundancy, and representation, nor was it found to be significant in 
terms of high-quality habitat or habitat that is otherwise important 
for the species' life history. As a result, while Cumberland River 
basin may have a different status, we determined it is not a 
significant portion of the range. Accordingly, no portion of the 
longsolid's range provides a basis for determining that the species is 
in danger of extinction in a significant portion of its range, and we 
determine that the species is likely to become in danger of extinction 
within the foreseeable future throughout all of its range. This does 
not conflict with the courts' holdings in Desert Survivors v. U.S. 
Department of the Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 
2018) and Center for Biological Diversity v. Jewell, 248 F. Supp. 3d 
946, 959 (D. Ariz. 2017) because, in reaching this conclusion, we did 
not apply the aspects of the Final

[[Page 14812]]

Policy, including the definition of ``significant'' that those court 
decisions held to be invalid.

Longsolid--Determination of Status

    Our review of the best available scientific and commercial 
information indicates that the longsolid meets the definition of a 
threatened species. Therefore, we are listing the longsolid as a 
threatened species in accordance with sections 3(20) and 4(a)(1) of the 
Act.

Round Hickorynut--Status Throughout All of Its Range

    After evaluating threats to the species and assessing the 
cumulative effect of the threats under the Act's section 4(a)(1) 
factors, we determined that the round hickorynut's abundance has been 
reduced across its range as demonstrated by both number of occupied 
management units and the number of populations where the species has 
historically occurred. Historically, the species occurred within 301 
populations and 138 management units across 12 States (plus at least 10 
populations and 8 management units within the Canadian Province of 
Ontario); currently, the species occurs in 69 populations and 36 
management units across 9 States, which represents a 77 percent 
reduction of its historically occupied populations (although we note 
that the remaining populations are widely distributed as opposed to 
concentrated within its range). The species also continues to occur in 
Canada, although it is estimated to have declined by greater than 92 
percent, as reported in 2013 (Committee on the Status of Species at 
Risk in Ontario 2013, p. 4). The conditions of the remaining 69 
currently extant populations in the United States vary between being 
highly resilient, moderately resilient, or having low resiliency (see 
Current Conditions, above, and section 5.2 in the SSA report (Service 
2019, pp. 43-47)).
    Currently, 4 round hickorynut populations (6 percent) are highly 
resilient, 16 (23 percent) are moderately resilient, and 49 (71 
percent) have low resiliency. Although downward trends are evident 
compared to historical information, 20 highly to moderately resilient 
populations in the United States continue to occupy 4 of the 5 major 
river basins where the species is historically known to occur. Current 
and ongoing threats from habitat degradation or loss (Factor A), and 
invasive, nonnative species (Factor E), contribute to the negative 
effects associated with the species' small population size (Factor E). 
The continued occupancy of these 20 populations (in addition to some 
survey information) implies that recent recruitment is occurring in 
some populations, and they maintain a level of resiliency, redundancy, 
and representation. Thus, after assessing the best available 
information, we conclude that the round hickorynut is not currently in 
danger of extinction throughout all of its range. Therefore, we proceed 
with determining whether the round hickorynut is likely to become an 
endangered species within the foreseeable future throughout all of its 
range.
    As noted above, the threats acting on the species include habitat 
degradation or loss from a variety of sources and invasive, nonnative 
species, both of which contribute to the negative effects associated 
with the species' small population size. Our analysis revealed that 
these threats are likely to continue into the foreseeable future, or 
approximately 20 to 30 years. This timeframe accounts for reasonable 
predictions of threats continuing into the future based on our 
examination of empirical data in our files (e.g., survey data, how 
threats are manifesting themselves on the landscape and the species, 
implementation of management plans and voluntary conservation actions), 
and also takes into consideration the biology of the species and the 
licensing schedules of dams within the species' range.
    The best available information, including our consideration of 
comments we received on the September 29, 2020 (85 FR 61384), proposed 
rule, suggests that the threats currently acting upon the round 
hickorynut are expected to continue into the foreseeable future. The 
effects of water quality and habitat degradation, and invasive, 
nonnative species, are reasonably expected to worsen over time, 
including concurrent with increasing human population trends, thus 
further reducing the species' resiliency, redundancy, and 
representation across its range. Our analysis reveals the potential for 
either none or a single population (i.e., the Grand River in Ohio) to 
persist as highly resilient (i.e., continued reproduction with varied 
age classes present) in the foreseeable future, assuming threats remain 
or worsen on the landscape. Additionally, the majority of the remaining 
populations would exhibit low resiliency, while many (between 33 and 71 
percent of the current low condition populations) would potentially 
become extinct or functionally extinct (e.g., significant habitat 
degradation; no reproduction due to highly isolated, non-recruiting 
individuals). Our future analysis also reveals a high risk that the 
species would become extirpated in two of the five historically 
occupied river basins (i.e., Cumberland River basin and Lower 
Mississippi River basin). Overall, the current threats acting on the 
species and its habitat are expected to continue, and there are no 
indications that these threats would be lessened or that declining 
population trends would be reverted. Thus, after assessing the best 
available information, we conclude that the round hickorynut is not 
currently in danger of extinction but is likely to become in danger of 
extinction within the foreseeable future throughout all of its range.

Round Hickorynut--Status Throughout a Significant Portion of Its Range

    See above, under Longsolid--Status Throughout a Significant Portion 
of Its Range, for a description of our evaluation methods and our 
policy application.
    In undertaking the analysis for the round hickorynut, we choose to 
address the status question first--we consider information pertaining 
to the geographic distribution of both the species and the threats that 
the species faces to identify portions of the range where the species 
may be endangered.
    We evaluated the range of the round hickorynut to determine if the 
species is in danger of extinction now in any portion of its range. The 
range of a species can theoretically be divided into portions in an 
infinite number of ways. We examined the species entire range in an 
attempt to focus this analysis on portions of the species' range that 
may meet the definition of an endangered species. For the round 
hickorynut, we considered whether the threats or their effects on the 
species are greater in any biologically meaningful portion of the 
species' range than in other portions such that the species is in 
danger of extinction now in that portion.
    As similarly described above for the longsolid, the statutory 
difference between an endangered species and a threatened species is 
the timeframe in which the species becomes in danger of extinction; an 
endangered species is in danger of extinction now while a threatened 
species is not in danger of extinction now but is likely to become so 
in the foreseeable future. Thus, we considered the time horizon for the 
threats that are driving the round hickorynut to warrant listing as a 
threatened species throughout all of its range. We then considered 
whether these threats or their effects are occurring in any portion of 
the species' range such that the species is in danger

[[Page 14813]]

of extinction now in that portion of its range. We examined the 
following threats: habitat degradation or loss; invasive, nonnative 
species; negative effects associated with small population size; and 
the potential for cumulative effects. We also considered whether these 
threats may be exacerbated by small population size (or low condition). 
Overall, we found that threats are likely acting on individuals or 
populations, or even basins, similarly across the species' range. These 
threats are certain to occur, and in those basins with few populations 
that are predominantly in low condition, these populations are facing 
the same threats, and these threats can be of greater magnitude in some 
areas or of greater impact, given small population sizes.
    Three of five basins where round hickorynut has historically 
occurred (Great Lakes, Cumberland River, and Lower Mississippi River 
basins) have been reduced to predominantly low condition populations. 
Specifically, the Great Lakes basin has been reduced from 25 
populations to 5 low condition populations, 1 medium condition 
population, and 1 high condition population; the Cumberland River basin 
has been reduced from 23 populations to 2 low condition populations; 
and the Lower Mississippi River basin has been reduced from 9 
populations to a single remaining low condition population. Although 
there are low condition populations in every basin in which the species 
occurs, because these three basins have seen their populations 
significantly reduced and a predominance of the Great Lakes basin 
populations and the remaining populations for the other two basins are 
currently in low condition, these circumstances--in combination with 
the other threats acting on the species throughout its range--may 
indicate that the species may be in danger of extinction now in these 
portions of the range.
    As similarly described above for the longsolid, small, isolated 
populations often exhibit reduced levels of genetic variability, which 
diminishes the species' capacity to adapt and respond to environmental 
changes, thereby decreasing the probability of long-term persistence. 
Small populations may experience reduced reproductive vigor, for 
example, due to inbreeding depression. Isolated individuals may have 
difficulty reproducing. The problems associated with small population 
size and vulnerability to random demographic fluctuations or natural 
catastrophes are further magnified by synergistic interactions with 
other threats, such as those discussed above. Based on our review of 
information and the synergistic effects of threats exacerbated by a 
predominance of populations in low condition within the Great Lakes, 
Cumberland, and Lower Mississippi River basins (where populations have 
been significantly extirpated), we find that these three basins are 
portions of the round hickorynut's range with a potential difference in 
biological condition.
    Because we have determined the Great Lakes, Cumberland, and Lower 
Mississippi River basins are portions of the range that may be in 
danger of extinction now, we next evaluate whether those portions may 
be significant (see additional discussion above for the longsolid). We 
first examined each of these area's contributions to the resiliency, 
redundancy, and representation of the species. Although these basins 
contain 10 of 69 populations (15 percent) identified in the SSA report, 
the Great Lakes basin consists of 1 population currently with moderate 
resiliency and 1 with high resiliency, and the remaining 5 populations 
demonstrate low resiliency; the remaining 3 populations in the 
Cumberland River basin and the Lower Mississippi River basin are all 
low condition populations. These low condition populations do not 
contribute significantly, either currently or in the foreseeable 
future, to the species' total resiliency at a biologically meaningful 
scale compared to other representative areas. Although the low 
condition populations in these basins are relatively small, the current 
and future redundancy suggests that threats would be unlikely to 
extirpate round hickorynut in the Great Lakes basin, but there is 
potential to lose the remaining three low condition populations under 
the current level of threats scenario (Scenario 1). Overall 
representation would be modified through loss of two currently occupied 
basins. We evaluated the best available information for the Great 
Lakes, Cumberland River, and Lower Mississippi River basins in this 
context, assessing each portion's significance in terms of these 
conservation concepts (i.e., resiliency, representation, and 
redundancy), and determined that there is not substantial information 
to indicate that any of these areas may be biologically significant to 
the species.
    Round hickorynut populations are widely distributed over nine 
States and five major river basins, and we considered geographic range 
as a surrogate for geographic variation and proxy for potential local 
adaptation and adaptive capacity. A river basin is any area of land 
where precipitation collects and drains off into a common outlet, such 
as into a river, bay, or other body of water. The river basin includes 
all the surface water from precipitation runoff and nearby streams that 
run downslope towards the shared outlet, as well as the groundwater 
underneath the earth's surface. River basins connect into other 
drainage basins at lower elevations in a hierarchical pattern, with 
smaller sub-drainage basins. Given there are no data indicating genetic 
or morphological differentiation between the five major river basins 
for the species, and these specific portions of the range do not 
provide high value or high quality habitat to the species as compared 
to the rest of the range, we conclude that these areas are not 
biologically significant to the round hickorynut. Further, the round 
hickorynut occurs in similar aquatic habitats across its range and does 
not use unique observable environmental or behavioral characteristics 
attributable to just the Great Lakes, Cumberland River, or Lower 
Mississippi River basin populations. Therefore, the species exhibits 
similar basin-scale use of habitat.
    The Great Lakes, Cumberland River, and Lower Mississippi River 
basin portions occur in stream habitat comprised of substrate types 
similar to the other basins where the round hickorynut performs the 
important life-history functions of breeding, feeding, and sheltering, 
and occur in areas with water quality sufficient to sustain these 
essential life-history traits. These three basins do not act as refugia 
for the species or as an important spawning ground. In addition, the 
water quality is similar throughout the species' range with impaired 
water quality occurring in all basins. Since the round hickorynut 
occurs in similar aquatic habitats across its range, the Great Lakes, 
Cumberland River, and Lower Mississippi River basin portions provide 
similar habitat characteristics as the remainder of the species' range. 
Therefore, there are no unique habitat characteristics attributable to 
just these basins, and these portions serve a similar role in 
supporting the species' viability as compared to the rest of the range.
    Overall, and in summary, we found three portions of the round 
hickorynut's range--the Great Lakes, Cumberland, and Lower Mississippi 
River basins--that may have a different status then the remaining 
portion of the round hickorynut's range. Our analysis indicated these 
three basins are not significant in terms of their contribution to the 
species' resiliency, redundancy,

[[Page 14814]]

and representation, nor were they found to be significant in terms of 
high-quality habitat or habitat that is otherwise important for the 
species' life history. As a result, while these portions may have a 
different biological status, we determined they are not significant 
portions of the species' range. Accordingly, no portion of the round 
hickorynut's range provides a basis for determining that the species is 
in danger of extinction in a significant portion of its range, and we 
determine that the round hickorynut is likely to become in danger of 
extinction within the foreseeable future throughout all of its range. 
This does not conflict with the courts' holdings in Desert Survivors v. 
U.S. Department of the Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. 
Cal. 2018) and Center for Biological Diversity v. Jewell, 248 F. Supp. 
3d 946, 959 (D. Ariz. 2017) because, in reaching this conclusion, we 
did not apply the aspects of the Final Policy, including the definition 
of ``significant'' that those court decisions held to be invalid.

Round Hickorynut--Determination of Status

    Our review of the best available scientific and commercial 
information indicates that the round hickorynut meets the definition of 
a threatened species. Therefore, we are listing the round hickorynut as 
a threatened species in accordance with sections 3(20) and 4(a)(1) of 
the Act.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition as a listed 
species, planning and implementation of recovery actions, requirements 
for Federal protection, and prohibitions against certain practices. 
Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies, 
including the Service, and the prohibitions against certain activities 
are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Section 4(f) of the Act calls for the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The goal of this process is to restore listed 
species to a point where they are secure, self-sustaining, and 
functioning components of their ecosystems.
    Recovery planning consists of preparing draft and final recovery 
plans, beginning with the development of a recovery outline shortly 
after a species is listed. The recovery outline guides the immediate 
implementation of urgent recovery actions and describes the process to 
be used to develop a recovery plan. Revisions of the plan may be done 
to address continuing or new threats to the species, as new substantive 
information becomes available. The recovery plan also identifies 
recovery criteria for review of when a species may be ready for 
reclassification from endangered to threatened (``downlisting'') or 
removal from protected status (``delisting''), and methods for 
monitoring recovery progress. Recovery plans also establish a framework 
for agencies to coordinate their recovery efforts and provide estimates 
of the cost of implementing recovery tasks. Recovery teams (composed of 
species experts, Federal and State agencies, nongovernmental 
organizations, and stakeholders) are often established to develop 
recovery plans. When completed, the recovery outline, draft recovery 
plan, and the final recovery plan will be available on our websites 
(https://ecos.fws.gov/ecp/species/9880, and https://ecos.fws.gov/ecp/species/9879), or from our Asheville Ecological Services Field Office 
(see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    Following publication of this rule, funding for recovery actions 
will be available from a variety of sources, including Federal budgets, 
State programs, and cost-share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the States of New York, Pennsylvania, 
Ohio, Indiana, Michigan, Kentucky, West Virginia, Virginia, North 
Carolina, Tennessee, Alabama, and Mississippi would be eligible for 
Federal funds to implement management actions that promote the 
protection or recovery of the longsolid or round hickorynut or both 
species. Information on our grant programs that are available to aid 
species recovery can be found at: https://www.fws.gov/service/financial-assistance.
    Please let us know if you are interested in participating in 
recovery efforts for the longsolid or round hickorynut. Additionally, 
we invite you to submit any new information on these species whenever 
it becomes available and any information you may have for recovery 
planning purposes (see FOR FURTHER INFORMATION CONTACT).
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is listed as an endangered or 
threatened species and with respect to its critical habitat, if any is 
designated. Regulations implementing this interagency cooperation 
provision of the Act are codified at 50 CFR part 402. Section 7(a)(2) 
of the Act requires Federal agencies to ensure that activities they 
authorize, fund, or carry out are not likely to jeopardize the 
continued existence of any endangered or threatened species or destroy 
or adversely modify its critical habitat. If a Federal action may 
affect a listed species or its critical habitat, the responsible 
Federal agency (action agency) must enter into consultation with the 
Service.
    Federal agency actions within the species' habitat that may require 
conference, consultation, or both as described in the preceding 
paragraph may include management and any other landscape-altering 
activities on Federal lands administered by the following agencies:
    (1) U.S. Army Corps of Engineers (channel dredging and maintenance; 
dam projects including flood control, navigation, hydropower, bridge 
projects, stream restoration, and Clean Water Act permitting).
    (2) U.S. Department of Agriculture, including the Natural Resources 
Conservation Service and Farm Service Agency (technical and financial 
assistance for projects) and the Forest Service (aquatic habitat 
restoration, fire management plans, fire suppression, fuel reduction 
treatments, forest plans, mining permits).

[[Page 14815]]

    (3) U.S. Department of Energy (renewable and alternative energy 
projects).
    (4) Federal Energy Regulatory Commission (interstate pipeline 
construction and maintenance, dam relicensing, and hydrokinetics).
    (5) U.S. Department of Transportation (highway and bridge 
construction and maintenance).
    (6) U.S. Fish and Wildlife Service (issuance of section 10 permits 
for enhancement of survival, habitat conservation plans, and safe 
harbor agreements; National Wildlife Refuge planning and refuge 
activities; Partners for Fish and Wildlife program projects benefiting 
these species or other listed species; Wildlife and Sportfish 
Restoration program sportfish stocking).
    (7) Environmental Protection Agency (water quality criteria, 
permitting).
    (8) Tennessee Valley Authority (flood control, navigation, 
hydropower, and land management for the Tennessee River system).
    (9) Office of Surface Mining Reclamation and Enforcement (land 
resource management plans, mining permits, oil and natural gas permits, 
abandoned mine land projects, and renewable energy development).
    (10) National Park Service (aquatic habitat restoration, fire 
management plans, fire suppression, fuel reduction treatments, land 
management plans, mining permits).
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of a listing on 
proposed and ongoing activities within the range of the listed species. 
The discussion below regarding protective regulations under section 
4(d) of the Act complies with our policy.

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

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the Secretary shall issue such regulations as she deems 
necessary and advisable to provide for the conservation of species 
listed as threatened. The U.S. Supreme Court has noted that statutory 
language like ``necessary and advisable'' demonstrates a large degree 
of deference to the agency (see Webster v. Doe, 486 U.S. 592 (1988)). 
Conservation is defined in the Act to mean the use of all methods and 
procedures which are necessary to bring any endangered species or 
threatened species to the point at which the measures provided pursuant 
to the Act are no longer necessary. Additionally, the second sentence 
of section 4(d) of the Act states that the Secretary may by regulation 
prohibit with respect to any threatened species any act prohibited 
under section 9(a)(1), in the case of fish or wildlife, or section 
9(a)(2), in the case of plants. Thus, the combination of the two 
sentences of section 4(d) provides the Secretary with wide latitude of 
discretion to select and promulgate appropriate regulations tailored to 
the specific conservation needs of the threatened species. The second 
sentence grants particularly broad discretion to the Service when 
adopting the prohibitions under section 9.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld rules 
developed under section 4(d) as a valid exercise of agency authority 
where they prohibited take of threatened wildlife or include a limited 
taking prohibition (see Alsea Valley Alliance v. Lautenbacher, 2007 
U.S. Dist. Lexis 60203 (D. Or. 2007); Washington Environmental Council 
v. National Marine Fisheries Service, 2002 U.S. Dist. Lexis 5432 (W.D. 
Wash. 2002)). Courts have also upheld 4(d) rules that do not address 
all of the threats a species faces (see State of Louisiana v. Verity, 
853 F.2d 322 (5th Cir. 1988)). As noted in the legislative history when 
the Act was initially enacted, ``once an animal is on the threatened 
list, the Secretary has an almost infinite number of options available 
to [her] with regard to the permitted activities for those species. 
[She] may, for example, permit taking, but not importation of such 
species, or [s]he may choose to forbid both taking and importation but 
allow the transportation of such species'' (H.R. Rep. No. 412, 93rd 
Cong., 1st Sess. 1973).
    Exercising its authority under section 4(d), we have developed a 
rule that is designed to address the longsolid's and round hickorynut's 
specific threats and conservation needs. Although the statute does not 
require us to make a ``necessary and advisable'' finding with respect 
to the adoption of specific prohibitions under section 9, we find that 
this rule as a whole satisfies the requirement in section 4(d) of the 
Act to issue regulations deemed necessary and advisable to provide for 
the conservation of the longsolid and round hickorynut. As discussed 
above under Summary of Biological Status and Threats, we have concluded 
that the longsolid and round hickorynut are likely to become in danger 
of extinction within the foreseeable future primarily due to declines 
in water quality; loss of stream flow; fragmentation, alteration, and 
deterioration of instream habitats; and nonnative species. These 
threats, which are expected to be exacerbated by continued urbanization 
and the effects of climate change, were central to our assessment of 
the future viability of the longsolid and round hickorynut. The 
provisions of this 4(d) rule will promote conservation of the longsolid 
and round hickorynut by encouraging management of the landscape in ways 
that meet both land management considerations and the conservation 
needs of the longsolid and round hickorynut and are consistent with 
land management considerations. The provisions of this rule are one of 
many tools that we will use to promote the conservation of the 
longsolid and round hickorynut.
    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are actions on State, Tribal, local, or 
private lands that require a Federal permit (such as a permit from the 
U.S. Army Corps of Engineers under section 404 of the Clean Water Act 
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10 
of the Act) or that involve some other Federal action (such as funding 
from the Federal Highway Administration, Federal Aviation 
Administration, or the Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat--and actions 
on State, Tribal, local, or private lands that are not federally 
funded, authorized, or carried out by a Federal agency--do not require 
section 7 consultation.
    This obligation does not change in any way for a threatened species 
with a species-specific 4(d) rule. Actions that result in a 
determination by a Federal agency of ``not likely to adversely affect'' 
continue to require the Service's written concurrence and actions that 
are ``likely to adversely affect'' a species

[[Page 14816]]

require formal consultation and the formulation of a biological 
opinion.

Provisions of the 4(d) Rule

    This 4(d) rule will provide for the conservation of the longsolid 
and round hickorynut by prohibiting the following activities, except as 
otherwise authorized or permitted: importing or exporting; take; 
possession and other acts with unlawfully taken specimens; delivering, 
receiving, carrying, transporting, or shipping in interstate or foreign 
commerce in the course of commercial activity; or selling or offering 
for sale in interstate or foreign commerce. This protective regulation 
includes most of these prohibitions because the longsolid and round 
hickorynut are at risk of extinction in the foreseeable future and 
putting these prohibitions in place will help to prevent further 
declines, preserve the species' remaining populations, slow their rate 
of decline, and decrease synergistic, negative effects from other 
ongoing or future threats.
    As discussed above under Summary of Biological Status and Threats, 
multiple factors are affecting the status of the longsolid and round 
hickorynut. A range of activities have the potential to affect these 
species, including declines in water quality, loss of stream flow, 
riparian and instream fragmentation, alteration and deterioration of 
instream habitats, and nonnative species. These threats, which are 
expected to be exacerbated by continued urbanization and the effects of 
climate change, were central to our assessment of the future viability 
of the longsolid and round hickorynut. Therefore, we prohibit actions 
resulting in the incidental take of longsolid and round hickorynut by 
altering or degrading the habitat. Regulating incidental take resulting 
from these activities will help preserve the species' remaining 
populations, slow their rate of decline, and decrease synergistic, 
negative effects from other stressors.
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulation at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Regulating 
incidental and intentional take of the longsolid and round hickorynut 
will help preserve and recover remaining populations of these species, 
including slowing their date of decline and decreasing negative effects 
from threats. Therefore, we prohibit intentional take of longsolid and 
round hickorynut, except for take resulting from those actions and 
activities specifically excepted by the 4(d) rule.
    The 4(d) rule provides for the conservation of the species by 
allowing exceptions, including certain standard exceptions, to 
incidental take prohibitions caused by actions and activities that, 
while they may have some minimal level of disturbance to the longsolid 
and round hickorynut, are not expected to negatively impact the 
species' conservation and recovery efforts. The proposed exceptions to 
these prohibitions include incidental take associated with (1) 
conservation and restoration efforts by State wildlife agencies, (2) 
channel restoration projects, (3) bank restoration projects, and (4) 
forest management activities that implement State-approved BMPs.
    The first exception is for incidental take associated with 
conservation and restoration efforts for listed species conducted by 
State wildlife agencies, and including, but not limited to, population 
monitoring, relocation, and collection of broodstock; tissue collection 
for genetic analysis; captive propagation; and subsequent stocking into 
currently occupied and unoccupied areas within the historical range of 
the species. We recognize our special and unique relationship with our 
State natural resource agency partners in contributing to conservation 
of listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we shall cooperate to the 
maximum extent practicable with the States in carrying out programs 
authorized by the Act. Therefore, in addition to the first exception 
for incidental take described above, any qualified employee or agent of 
a State conservation agency that is a party to a cooperative agreement 
with us in accordance with section 6(c) of the Act, who is designated 
by his or her agency for such purposes, and coordinates these 
activities with us, would be able to conduct activities designed to 
conserve the longsolid and round hickorynut that may result in 
otherwise prohibited take without additional authorization.
    The second exception is for incidental take resulting from channel 
and bank restoration projects for creation of natural, physically 
stable, ecologically functioning streams (or stream and wetland 
systems) that are reconnected with their groundwater aquifers. These 
projects can be accomplished using a variety of methods, but the 
desired outcome is a natural channel with low shear stress (force of 
water moving against the channel); bank heights that enable 
reconnection to the floodplain; a reconnection of surface and 
groundwater systems, resulting in perennial flows in the channel; 
riffles and pools composed of existing soil, rock, and wood instead of 
large imported materials; low compaction of soils within adjacent 
riparian areas; and inclusion of riparian wetlands.
    The third exception is for incidental take caused by bank 
stabilization projects that use bioengineering methods to replace pre-
existing, bare, eroding stream banks with vegetated, stable stream 
banks, thereby reducing bank erosion and instream sedimentation and 
improving habitat conditions for the species. Following these 
bioengineering methods, stream banks may be stabilized using native 
species live stakes (live, vegetative cuttings inserted or tamped into 
the ground in a manner that allows the stake to take root and grow), 
native species live fascines (live branch cuttings, usually willows, 
bound together into long, cigar-shaped bundles), or native species 
brush layering (cuttings or branches of easily rooted tree species 
layered between successive lifts of soil fill). Native species 
vegetation includes woody and herbaceous species appropriate for the 
region and habitat conditions. These methods will not include the sole 
use of quarried rock (rip-rap) or the use of rock baskets or gabion 
structures. Prior to channel restoration and bank stabilization 
actions, surveys conducted in coordination with the appropriate Service 
field office to determine presence of longsolid and round hickorynut 
must be performed, and if located, relocation prior to project 
implementation may be necessary, with post-implementation monitoring.
    The fourth exception is for incidental take associated with forest 
management activities that implement State-approved BMPs. Forest 
landowners who properly implement these BMPs are helping conserve the 
longsolid and round hickorynut, and this 4(d) rule is an incentive for 
all landowners to properly implement BMPs to avoid any take 
implications.
    We reiterate that these actions and activities may result in some 
minimal level of take of the longsolid and round hickorynut, but they 
are unlikely to negatively impact the species'

[[Page 14817]]

conservation and recovery efforts. To the contrary, we expect they 
would have a net beneficial effect on the species. Across the species' 
range, instream habitats have been degraded physically by sedimentation 
and by direct channel disturbance. The activities in the 4(d) rule are 
intended to improve habitat conditions for the species in the long 
term.
    We may issue permits to carry out otherwise prohibited activities, 
including those described above, involving threatened wildlife under 
certain circumstances. Regulations governing permits are codified at 50 
CFR 17.32. With regard to threatened wildlife, a permit may be issued 
for the following purposes: For scientific purposes, to enhance 
propagation or survival, for economic hardship, for zoological 
exhibition, for educational purposes, for incidental taking, or for 
special purposes consistent with the purposes of the Act. The statute 
also contains certain exemptions from the prohibitions, which are found 
in sections 9 and 10 of the Act.
    We recognize the special and unique relationship with our State 
natural resource agency partners in contributing to conservation of 
listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we must cooperate to the 
maximum extent practicable with the States in carrying out programs 
authorized by the Act. Therefore, any qualified employee or agent of a 
State conservation agency that is a party to a cooperative agreement 
with us in accordance with section 6(c) of the Act, who is designated 
by his or her agency for such purposes, will be able to conduct 
activities designed to conserve the longsolid and round hickorynut that 
may result in otherwise prohibited take without additional 
authorization.
    Nothing in this 4(d) rule will change in any way the recovery 
planning provisions of section 4(f) of the Act, the consultation 
requirements under section 7 of the Act, or the ability of the Service 
to enter into partnerships for the management and protection of the 
longsolid and round hickorynut. However, interagency cooperation may be 
further streamlined through planned programmatic consultations for the 
species between Federal agencies and the Service.

III. Critical Habitat for the Longsolid and Round Hickorynut

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features:
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Our regulations at 50 CFR 424.02 define the geographical area 
occupied by the species as an area that may generally be delineated 
around species' occurrences, as determined by the Secretary (i.e., 
range). Such areas may include those areas used throughout all or part 
of the species' life cycle, even if not used on a regular basis (e.g., 
migratory corridors, seasonal habitats, and habitats used periodically, 
but not solely by vagrant individuals).
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the destruction or adverse modification of 
critical habitat. The designation of critical habitat does not affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. Such designation 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. Where a landowner requests Federal 
agency funding or authorization for an action that may affect a listed 
species or critical habitat, the Federal agency would be required to 
consult with the Service under section 7(a)(2) of the Act. However, 
even if the Service were to conclude that the proposed activity would 
likely result in destruction or adverse modification of the critical 
habitat, the Federal action agency and the landowner are not required 
to abandon the proposed activity, or to restore or recover the species; 
instead, they must implement ``reasonable and prudent alternatives'' to 
avoid destruction or adverse modification of critical habitat.
    Under the first prong of the Act's definition of critical habitat, 
areas within the geographical area occupied by the species at the time 
it was listed are included in a critical habitat designation if they 
contain physical or biological features (1) which are essential to the 
conservation of the species and (2) which may require special 
management considerations or protection. For these areas, critical 
habitat designations identify, to the extent known using the best 
scientific data available, those physical or biological features that 
are essential to the conservation of the species (such as space, food, 
cover, and protected habitat).
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original

[[Page 14818]]

sources of information as the basis for recommendations to designate 
critical habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information from the SSA report and information developed during the 
listing process for the species. Additional information sources may 
include any generalized conservation strategy, criteria, or outline 
that may have been developed for the species; the recovery plan for the 
species; articles in peer-reviewed journals; conservation plans 
developed by States and counties; scientific status surveys and 
studies; biological assessments; other unpublished materials; or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. We recognize that critical habitat designated at a 
particular point in time may not include all of the habitat areas that 
we may later determine are necessary for the recovery of the species. 
For these reasons, a critical habitat designation does not signal that 
habitat outside the designated area is unimportant or may not be needed 
for recovery of the species. Areas that are important to the 
conservation of the species, both inside and outside the critical 
habitat designation, will continue to be subject to: (1) Conservation 
actions implemented under section 7(a)(1) of the Act; (2) regulatory 
protections afforded by the requirement in section 7(a)(2) of the Act 
for Federal agencies to ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species; and (3) the prohibitions found in the section 4(d) rule. 
Federally funded or permitted projects affecting listed species outside 
their designated critical habitat areas may still result in jeopardy 
findings in some cases. These protections and conservation tools will 
continue to contribute to recovery of these species. Similarly, 
critical habitat designations made on the basis of the best available 
information at the time of designation will not control the direction 
and substance of future recovery plans, habitat conservation plans 
(HCPs), or other species conservation planning efforts if new 
information available at the time of these planning efforts calls for a 
different outcome.

Physical or Biological Features Essential to the Conservation of the 
Species

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12(b), in determining which areas we will designate as 
critical habitat from within the geographical area occupied by the 
species at the time of listing, we consider the physical or biological 
features that are essential to the conservation of the species and 
which may require special management considerations or protection. The 
regulations at 50 CFR 424.02 define ``physical or biological features 
essential to the conservation of the species'' as the features that 
occur in specific areas and that are essential to support the life-
history needs of the species, including, but not limited to, water 
characteristics, soil type, geological features, sites, prey, 
vegetation, symbiotic species, or other features. A feature may be a 
single habitat characteristic or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity. For example, 
physical features essential to the conservation of the species might 
include gravel of a particular size required for spawning, alkaline 
soil for seed germination, protective cover for migration, or 
susceptibility to flooding or fire that maintains necessary early-
successional habitat characteristics. Biological features might include 
prey species, forage grasses, specific kinds or ages of trees for 
roosting or nesting, symbiotic fungi, or 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.
    As described above under Summary of Biological Status and Threats, 
longsolid and round hickorynut mussels occur in river or stream 
reaches. Occasional or regular interaction among individuals in 
different reaches not interrupted by a barrier likely occurs, but in 
general, interaction is strongly influenced by habitat fragmentation 
and distance between occupied river or stream reaches. Once released 
from their fish host, freshwater mussels are benthic, generally 
sedentary aquatic organisms and closely associated with appropriate 
habitat patches within a river or stream.
    We derive the specific physical or biological features essential 
for the longsolid and round hickorynut from studies of these species' 
(or appropriate surrogate species') habitat, ecology, and life history. 
The primary habitat elements that influence resiliency of the longsolid 
and round hickorynut include water quality, water quantity, substrate, 
habitat connectivity, and the presence of host fish species to ensure 
recruitment. These features are also described above as resource needs 
under Summary of Biological Status and Threats, and a full description 
is available in the SSA reports; the individuals' needs are summarized 
below in Table 1.

[[Page 14819]]



             Table 1--Requirements for Each Life Stage of the Longsolid and Round Hickorynut Mussels
----------------------------------------------------------------------------------------------------------------
                                         Resources needed to complete life stage
              Life stage                                   \1\                                 Source
----------------------------------------------------------------------------------------------------------------
Fertilized eggs--early spring........   Clear, flowing water               Berg et al. 2008, p. 397;
                                        Sexually mature males upstream      Haag 2012, pp. 38-39.
                                        from sexually mature females
                                        Appropriate spawning temperatures
Glochidia--late spring to early         Clear, flowing water               Strayer 2008, p. 65; Haag
 summer.                                Enough flow to keep glochidia or    2012, pp. 41-42.
                                        conglutinates adrift and to attract drift-
                                        feeding host fish
                                        Presence of host fish for
                                        attachment
Juveniles--excystment from host fish    Clear, flowing water               Dimock and Wright 1993, pp.
 to approx. 0.8 in (~20 mm) shell       Host fish dispersal                 188-190; Sparks and Strayer
 length.                                Appropriate interstitial            1998, p. 132; Augspurger et
                                        chemistry; low salinity, low ammonia, low   al. 2003, p. 2,574;
                                        copper and other contaminants, high         Augspurger et al. 2007, p.
                                        dissolved oxygen                            2,025; Strayer and Malcom
                                        Appropriate substrate (clean        2012, pp. 1,787-1,788.
                                        gravel/sand/cobble) for settlement
Adults--greater than 0.8 in (20 mm)     Clear, flowing water               Yeager et al. 1994, p. 221;
 shell length.                          Appropriate substrate (stable       Nichols and Garling 2000, p.
                                        gravel and coarse sand free from            881; Chen et al. 2001, p.
                                        excessive silt)                             214; Spooner and Vaughn
                                        Adequate food availability          2008, p. 308.
                                        (phytoplankton and detritus)
                                        High dissolved oxygen
                                        Appropriate water temperature
----------------------------------------------------------------------------------------------------------------
\1\ These resource needs are common among North American freshwater mussels; however, due to lack of species-
  specific research, parameters specific to longsolid and round hickorynut are unavailable.

Summary of Essential Physical or Biological Features

    We derive the specific physical or biological features essential to 
the conservation of the longsolid and round hickorynut from studies of 
the species' habitat, ecology, and life history as described below. 
Additional information can be found in chapter 4 of the SSA reports 
(Service 2018, pp. 27-32; Service 2019, pp. 30-39), both of which are 
available on https://www.regulations.gov under Docket No. FWS-R4-ES-
2020-0010. We have determined that the following physical or biological 
features are essential to the conservation of the longsolid and round 
hickorynut:
    (1) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species are found and to maintain stream connectivity, specifically 
providing for the exchange of nutrients and sediment for maintenance of 
the mussels' and fish host's habitat and food availability, maintenance 
of spawning habitat for native fishes, and the ability for newly 
transformed juveniles to settle and become established in their 
habitats. Adequate flows ensure delivery of oxygen, enable 
reproduction, deliver food to filter-feeding mussels, and reduce 
contaminants and fine sediments from interstitial spaces. Stream 
velocity is not static over time, and variations may be attributed to 
seasonal changes (with higher flows in winter/spring and lower flows in 
summer/fall), extreme weather events (e.g., drought or floods), or 
anthropogenic influence (e.g., flow regulation via impoundments).
    (2) Suitable substrates and connected instream habitats, 
characterized by geomorphically 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) with habitats that support a diversity of freshwater mussel 
and native fish (such as, stable riffle-run-pool habitats that provide 
flow refuges consisting of predominantly silt-free, stable sand, 
gravel, and cobble substrates).
    (3) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including (but not limited to): Dissolved oxygen 
(generally above 2 to 3 parts per million (ppm)), salinity (generally 
below 2 to 4 ppm), and temperature (generally below 86 [deg]F ([deg]F) 
(30 [deg]Celsius ([deg]C)). Additionally, water and sediment should be 
low in ammonia (generally below 0.5 ppm total ammonia-nitrogen) and 
heavy metal concentrations, and lack excessive total suspended solids 
and other pollutants (see Threats Analysis, above).
    (4) The presence and abundance of fish hosts necessary for 
recruitment of the longsolid (currently unknown, likely includes 
minnows of the family Cyprinidae and banded sculpin (Cottus carolinae)) 
and the round hickorynut (i.e., eastern sand darter (Ammocrypta 
pellucida), emerald darter (Etheostoma baileyi), greenside darter (E. 
blennioides), Iowa darter (E. exile), fantail darter (E. flabellare), 
Cumberland darter (E. susanae), spangled darter (E. obama), variegate 
darter (E. variatum), blackside darter (Percina maculata), frecklebelly 
darter (P. stictogaster), and banded sculpin).

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features which are essential to the conservation of 
the species and which may require special management considerations or 
protection.
    The features essential to the conservation of the longsolid and 
round hickorynut may require special management considerations or 
protections to reduce the following threats: (1) Alteration of the 
natural flow regime (modifying the natural hydrograph and seasonal 
flows), including water withdrawals, resulting in flow reduction and 
available water quantity; (2) urbanization of the landscape, including 
(but not limited to) land conversion for urban and commercial use, 
infrastructure (pipelines, roads, bridges, utilities), and urban water 
uses (resource extraction activities, water supply reservoirs,

[[Page 14820]]

wastewater treatment, etc.); (3) significant alteration of water 
quality and nutrient pollution from a variety of activities, such as 
mining and agricultural activities; (4) impacts from invasive species; 
(5) land use activities that remove large areas of forested wetlands 
and riparian systems; (6) culvert and pipe installation that creates 
barriers to movement for the longsolid and round hickorynut, or their 
host fishes; (7) changes and shifts in seasonal precipitation patterns 
as a result of climate change; and (8) other watershed and floodplain 
disturbances that release sediments, pollutants, or nutrients into the 
water.
    Management activities that could ameliorate these threats include, 
but are not limited to: Use of BMPs designed to reduce sedimentation, 
erosion, and bank destruction; protection of riparian corridors and 
woody vegetation; moderation of surface and ground water withdrawals to 
maintain natural flow regimes; improved stormwater management; and 
reduction of other watershed and floodplain disturbances that release 
sediments, pollutants, or nutrients into the water.
    In summary, we find that the occupied areas we are designating as 
critical habitat contain the physical or biological features that are 
essential to the conservation of the species and that may require 
special management considerations or protection. Special management 
considerations or protection may be required of the Federal action 
agency to eliminate, or to reduce to negligible levels, the threats 
affecting the physical and biological features of each unit.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available to designate critical habitat. In accordance 
with the Act and our implementing regulations at 50 CFR 424.12(b), we 
review available information pertaining to the habitat requirements of 
the species and identify specific areas within the geographical area 
occupied by the species at the time of listing and any specific areas 
outside the geographical area occupied by the species to be considered 
for designation as critical habitat. We are not designating any areas 
outside the geographical area occupied by the longsolid or round 
hickorynut 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 two species.

Methodology Used For Selection of Units

    First, we included stronghold (high) or medium condition 
populations (resiliency) remaining from historical conditions. These 
populations show recruitment or varied age class structure, and could 
be used for recovery actions to re-establish populations within basins 
through propagation activities or augment other populations through 
direct translocations within their basins.
    Second, we evaluated spatial representation and redundancy across 
the species' ranges, to include last remaining consistently observable 
population(s) in major river basins and the last remaining 
population(s) in States if necessary, as States are crucial partners in 
monitoring and recovery efforts.
    Third, we examined the overall contribution of medium condition 
populations and threats to those populations. Adjacency and 
connectivity to stronghold and medium populations was considered, and 
we did not include populations that have a potentially low likelihood 
of recovery due to limited abundances or populations currently under a 
high level of threats.
    Finally, we evaluated overlap of longsolid and round hickorynut 
occurrences, as well as other listed aquatic species and designated 
critical habitat, to see if there are ongoing conservation and 
monitoring efforts that can be capitalized on for efficiency. Rangewide 
recovery considerations, such as maintaining existing genetic diversity 
and striving for representation of all major portions of the species' 
current ranges, were considered in formulating these critical habitat 
designations. For example, in the Cumberland River basin, there is only 
one remaining population of the longsolid (mainstem Cumberland River) 
and only two populations remaining of the round hickorynut (Buck Creek 
and Rockcastle River). In addition, in the Mississippi River basin, 
only one population of the round hickorynut remains (Big Black River). 
The distribution of the longsolid and round hickorynut in these basins 
is substantially reduced when compared to historical data that indicate 
these species were formerly much more widespread within these 
drainages. Therefore, these rivers and streams were included to 
maintain basin representation.
    The critical habitat designation does not include all rivers and 
streams currently occupied by the species, nor all rivers and streams 
known to have been occupied by the species historically. Instead, it 
includes only the occupied rivers and streams within the current range 
that we determined have the physical or biological features that are 
essential to the conservation of these species and meet the definition 
of critical habitat. These rivers and streams contain populations large 
and dense enough and most likely to be self-sustaining over time 
(despite fluctuations in local conditions), and also have retained the 
physical or biological features that will allow for the maintenance and 
expansion of existing populations. These units also represent 
populations that are stable and distributed over a wide geographic 
area. We are not designating any areas outside the geographical area 
currently occupied by either the longsolid or round hickorynut because 
we determined that occupied areas are sufficient to conserve the two 
species. Accordingly, we did not find any unoccupied areas to be 
essential to the conservation of these species.
    Sources of data for these critical habitat designations include 
multiple databases maintained by universities, information from State 
agencies throughout the species' ranges, and numerous survey reports on 
streams throughout the species' ranges (see SSA reports (Service 2018, 
entire; Service 2019, entire)). We have also reviewed available 
information that pertains to the habitat requirements of these species. 
Sources of information on habitat requirements include studies 
conducted at occupied sites and published in peer-reviewed articles, 
agency reports, and data collected during monitoring efforts (Service 
2018, entire; Service 2019, entire).
    In summary, for areas within the geographic area occupied by these 
species at the time of listing, we delineated critical habitat unit 
boundaries using a precise set of criteria. Specifically, we identified 
river and stream reaches with observations from 2000 to present, given 
the variable data associated with timing and frequency of mussel 
surveys conducted throughout the species' ranges. We determined it is 
reasonable to find these areas occupied due to the longevity of the 
longsolid, the potential for incomplete survey detections for the round 
hickorynut, highly variable recent survey information across both 
species' ranges, and available State heritage databases and information 
support for the likelihood of both species' continued presence in these 
areas within this timeframe. Specific habitat areas were delineated 
based on Natural

[[Page 14821]]

Heritage Element Occurrences, and unpublished survey data provided by 
States, universities, and nongovernmental organizations. These areas 
provide habitat for longsolid and round hickorynut populations and are 
large enough to be self-sustaining over time, despite fluctuations in 
local conditions. The areas within the critical habitat units represent 
continuous river and stream reaches of free-flowing habitat patches 
capable of sustaining host fishes and allowing for seasonal transport 
of glochidia, which are essential for reproduction and dispersal of 
longsolid and round hickorynut. We consider portions of the following 
rivers and streams to be occupied by the species at the time of 
listing, and meet the definition of critical habitat:
    (1) Longsolid--French Creek, Allegheny River, Shenango River, 
Middle Island Creek, Little Kanawha River, Elk River, Kanawha River, 
Licking River, Green River, Cumberland River, Clinch River, and Paint 
Rock River (see Final Critical Habitat Designation, below).
    (2) Round hickorynut--Shenango River, Grand River, Tippecanoe 
River, Middle Island Creek, Little Kanawha River, Elk River, Kanawha 
River, Licking River, Rockcastle River, Buck Creek, Green River, Paint 
Rock River, Duck River, and Big Black River (see Final Critical Habitat 
Designation, below).

Critical Habitat Maps

    When determining critical habitat boundaries, we made every effort 
to avoid including developed areas such as lands covered by buildings, 
pavement, and other structures because such lands lack physical or 
biological features necessary for the longsolid and round hickorynut. 
The scale of the maps we prepared under the parameters for publication 
within the Code of Federal Regulations may not reflect the exclusion of 
such developed lands. Any such lands inadvertently left inside critical 
habitat boundaries shown on the maps of this rule have been excluded by 
text in the rule and are not designated as critical habitat. Therefore, 
a Federal action involving these lands will not trigger section 7 
consultation with respect to critical habitat and the requirement of no 
adverse modification unless the specific action will affect the 
physical or biological features in the adjacent critical habitat.
    We are designating as critical habitat stream reaches that we have 
determined are occupied at the time of listing (i.e., currently 
occupied) and that contain one or more of the physical or biological 
features that are essential to support life-history processes of these 
species. Twelve units for the longsolid and 14 units for the round 
hickorynut are designated based on the presence of the physical or 
biological features that support the longsolid's or round hickorynut's 
life-history processes. All of the units for both species contain all 
of the identified physical or biological features and support multiple 
life-history processes.
    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 
https://www.regulations.gov at Docket No. FWS-R4-ES-2020-0010.

Final Critical Habitat Designation

    We are designating a total of 1,115 river mi (1,794 km) in 12 units 
as occupied critical habitat for the longsolid and a total of 921 river 
mi (1,482 km) in 14 units as occupied critical habitat for the round 
hickorynut. All or portions of some of these units overlap, and all 26 
units are occupied by one or both species. The critical habitat areas 
we describe below constitute our current best assessment of areas that 
meet the definition of critical habitat for the longsolid and round 
hickorynut. The 12 areas designated as critical habitat for the 
longsolid are: French Creek, Allegheny River, Shenango River, Middle 
Island Creek, Little Kanawha River, Elk River, Kanawha River, Licking 
River, Green River, Cumberland River, Clinch River, and Paint Rock 
River. The 14 areas designated as critical habitat for the round 
hickorynut are: Shenango River, Grand River, Tippecanoe River, Middle 
Island Creek, Little Kanawha River, Elk River, Kanawha River, Licking 
River, Rockcastle River, Buck Creek, Green River, Paint Rock River, 
Duck River, and Big Black River. Tables 2 and 3 show the critical 
habitat units and the approximate river miles of each unit.

    Table 2--Critical Habitat Units for the Longsolid. All Units Are
                         Occupied by the Species
      [Area estimates reflect all land within critical habitat unit
                               boundaries]
------------------------------------------------------------------------
                                   Adjacent riparian
 Critical habitat unit  (State)    land ownership by  Approximate  river
                                         type         miles (kilometers)
------------------------------------------------------------------------
LS 1. French Creek                Public (Federal,    14 (22.1)
 (Pennsylvania).                   State);.
                                  Private...........  106 (170.6)
                                                      Total = 120
                                                       (191.5)
LS 2. Allegheny River             Public (Federal,    84 (135.8)
 (Pennsylvania).                   State);.
                                  Private...........  15 (24.1)
                                                      Total = 99 (159.3)
LS 3. Shenango River              Public (Federal,    7 (11.3)
 (Pennsylvania).                   State);.
                                  Private...........  15 (24.3)
                                                      Total = 22 (35.5)
LS 4. Middle Island Creek (West   Public (Local);...  0.13 (0.2)
 Virginia).
                                  Private...........  14 (23.5)
                                                      Total = 14 (23.7)
LS 5. Little Kanawha River (West  Public (Federal,    0.53 (0.9)
 Virginia).                        State);.
                                  Private...........  122 (197.2)
                                                      Total = 123 (198)
LS 6. Elk River (West Virginia).  Public (Federal,    7 (12.7)
                                   State, Local);.
                                  Private...........  93 (150.3)
                                                      Total = 101 (163)
LS 7. Kanawha River (West         Public (Federal,    2 (4.6)
 Virginia).                        State, Local);.
                                  Private...........  18 (29.3)
                                                      Total = 21 (33.9)
LS 8. Licking River (Kentucky)..  Public (Federal,    19 (31.7)
                                   State, Local);.

[[Page 14822]]

 
                                  Private...........  161 (259.7)
                                                      Total = 181
                                                       (291.5)
LS 9. Green River (Kentucky)....  Public (Federal,    51 (82.4)
                                   State, Local);.
                                  Private...........  105 (169.2)
                                                      Total = 156
                                                       (251.6)
LS 10. Cumberland River           Public (Federal)..  Total = 48 (77.5)
 (Tennessee).
LS 11. Clinch River (Virginia     Public (Federal,    17 (27.3)
 and Tennessee).                   State);.
                                  Private...........  160 (258.8)
                                                      Total = 177
                                                       (286.1)
LS 12. Paint Rock River           Public (Federal,    56 (90.4)
 (Alabama).                        State);.
                                  Private...........  2 (4.1)
                                                      Total = 58 (94.5)
                                 ---------------------------------------
    Public......................  ..................  305 (491)
    Private.....................  ..................  810 (1,304)
                                 ---------------------------------------
        Total...................  ..................  1,115 (1,794)
------------------------------------------------------------------------
Note: River miles may not sum due to rounding.


 Table 3--Critical Habitat Units for the Round Hickorynut. All Units Are
                         Occupied by the Species
      [Area estimates reflect all land within critical habitat unit
                               boundaries]
------------------------------------------------------------------------
                                  Adjacent riparian       Approximate
     Critical habitat unit        land ownership  by      river miles
                                         type             (kilometers)
------------------------------------------------------------------------
RH 1. Shenango River            Public (Federal,                7 (11.1)
 (Pennsylvania).                 State);.
                                Private..............          15 (24.3)
                                                       Total = 22 (35.5)
RH 2. Grand River (Ohio)......  Public (State,                   33 (53)
                                 Local);.
                                Private..............          59 (95.2)
                                                              Total = 92
                                                                 (148.2)
RH 3. Tippecanoe River          Public (State,                  9 (14.5)
 (Indiana).                      Easement);.
                                Private..............         66 (105.6)
                                                              Total = 75
                                                                 (120.8)
RH 4. Middle Island Creek       Public (Federal,               0.2 (0.4)
 (West Virginia).                State);.
                                Private..............       74.8 (120.4)
                                                              Total = 75
                                                                 (120.8)
RH 5. Little Kanawha River      Public (Federal,               0.7 (1.2)
 (West Virginia).                State, Local);.
                                Private..............        109 (175.4)
                                                             Total = 110
                                                                 (176.6)
RH 6. Elk River (West           Public (Federal,                7 (12.7)
 Virginia).                      State, Local);.
                                Private..............         93 (150.3)
                                                       Total = 101 (163)
RH 7. Kanawha River (West       Public (Federal,                 4 (7.2)
 Virginia).                      State, Local);.
                                Private..............          33 (53.2)
                                                            Total = 37.5
                                                                  (60.4)
RH 8. Licking River (Kentucky)  Public (Federal,                 18 (30)
                                 State, Local);.
                                Private..............        131 (211.8)
                                                             Total = 150
                                                                 (241.9)
RH 9. Rockcastle River          Public (Federal);....          15 (24.2)
 (Kentucky).
                                Private..............          0.3 (0.4)
                                                            Total = 15.3
                                                                  (24.6)
RH 10. Buck Creek (Kentucky)..  Public (State,                   3 (5.5)
                                 Local);.
                                Private..............          33 (52.6)
                                                       Total = 36 (58.1)
RH 11. Green River (Kentucky).  Public (Federal,               37 (59.4)
                                 State);.
                                Private..............          61 (98.4)
                                                              Total = 98
                                                                 (157.7)
RH 12. Paint Rock River         Public (Federal,               46 (73.4)
 (Alabama).                      State);.
                                Private..............            2 (4.1)
                                                       Total = 48 (77.5)
RH 13. Duck River (Tennessee).  Public (State,                 32 (51.1)
                                 Local);.
                                Private..............          27 (43.7)
                                                       Total = 59 (94.8)
RH 14. Big Black River          Private..............      Total = 4 (7)
 (Mississippi).
                                                      ------------------

[[Page 14823]]

 
    Public....................  .....................          212 (341)
    Private...................  .....................        709 (1,141)
                                                      ------------------
        Total.................  .....................        921 (1,482)
------------------------------------------------------------------------
Note: River miles may not sum due to rounding.

    We present brief descriptions of all units, and reasons why they 
meet the definition of critical habitat for the longsolid and round 
hickorynut, below. There are a total of 12 units for the longsolid and 
14 units for round hickorynut, 8 of which overlap in part or whole for 
both species, and all of which contain all of the physical and 
biological features essential to the conservation of both species. 
Also, the majority of units overlap in part or whole with existing 
critical habitat designated for other federally endangered species 
(i.e., diamond darter (Crystallaria cincotta), Short's bladderpod 
(Physaria globosa), purple bean (Villosa perpurpurea), rough 
rabbitsfoot (Quadrula cylindrica strigillata), Cumberlandian combshell 
(Epioblasma brevidens), oyster mussel (Epioblasma capsaeformis), 
slabside pearlymussel (Pleuronaia (=Lexingtonia) dolabelloides), and 
fluted kidneyshell (Ptychobranchus subtentus)) or federally threatened 
species (i.e., rabbitsfoot (Quadrula cylindrica cylindrica), yellowfin 
madtom (Noturus flavipinnis), and slender chub (Erimystax (=Hybopsis) 
cahni)), as specified below.

LS 1: French Creek

    Unit LS 1 consists of 120 stream mi (191.5 km) of French Creek in 
Crawford, Erie, Mercer, and Venango Counties, Pennsylvania, from Union 
City Dam west of Union City, Erie County, downstream to its confluence 
with the Allegheny River near the City of Franklin, Venango County. 
Riparian lands that border the unit include approximately 106 stream mi 
(170.6 km; 76 percent) in private ownership and 14 stream mi (22.1 km; 
24 percent) in public (Federal or State) ownership. General land use on 
adjacent riparian lands and the surrounding HUC 8-level management unit 
includes agriculture, several State-managed game lands, the communities 
of Cambridge Springs and Venango, and the cities of Meadville and 
Franklin. Union City Dam is operated by the U.S. Army Corps of 
Engineers. Unit LS 1 is occupied by the species and contains all of the 
physical or biological features essential to the conservation of the 
species. The entire 120 stream mi (191.5 km) of this unit overlap with 
designated critical habitat for the federally threatened rabbitsfoot 
mussel (80 FR 24692; April 30, 2015).
    Threats identified within this unit include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to resource extraction, agriculture, timbering practices, and human 
development; flow reduction and water quality degradation due to water 
withdrawals and wastewater treatment plants; and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
monitoring water quality degradation within the species' range 
resulting from row crop agriculture and oil and gas development, and 
efforts to prevent the spread of invasive, nonnative species, 
specifically the round goby (see Special Management Considerations or 
Protection, above).

LS 2: Allegheny River

    Unit LS 2 consists of 99 river mi (159.3 km) of the Allegheny River 
in Warren, Crawford, Forest, Venango, and Clarion Counties, 
Pennsylvania, from Kinzua Dam east of Warren, Warren County, downstream 
to the Pennsylvania Route 58 crossing at Foxburg, Clarion County, 
Pennsylvania. Riparian lands that border the unit include approximately 
15 river mi (24.1 km; 14 percent) in private ownership and 84 river mi 
(135.8 km; 86 percent) in public (Federal or State government) 
ownership. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit includes forestry, agriculture, 
and State-managed game lands. The public land ownership for this unit 
is a combination of Allegheny National Forest lands and State lands, 
and the Kinzua Dam is operated by the U.S. Army Corps of Engineers. 
Unit LS 2 is occupied by the species and contains all of the physical 
or biological features essential to the conservation of the species. 
There is overlap of approximately 35 river mi (57 km) of this unit with 
designated critical habitat for the federally threatened rabbitsfoot 
mussel (80 FR 24692; April 30, 2015).
    Threats identified within Unit LS 2 include the degradation of 
habitat and water quality from impoundments, channelization, siltation 
and pollution due to improper timbering practices, resource extraction, 
water withdrawals, development, and wastewater treatment plants, and 
the presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include modifying dam releases from Kinzua Dam to mimic the 
natural hydrograph, improvements to water quality to reverse 
degradation resulting from row crop agriculture and oil and gas 
development, and efforts to prevent the spread of invasive, nonnative 
species (see Special Management Considerations or Protection, above).

LS 3: Shenango River

    Unit LS 3 is the same as Unit RH 1, described below for the round 
hickorynut. Unit LS 3 consists of 22 river mi (35.5 km) of the Shenango 
River in Crawford County, Pennsylvania, from Pymatuning Dam downstream 
to the point of inundation by Shenango River Lake near Big Bend, Mercer 
County, Pennsylvania. Riparian lands that border the unit include 
approximately 15 river mi (24.3 km; 32 percent) in private ownership 
and 7 river mi (11.3 km; 68 percent) in public (Federal or State) 
ownership. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit includes the City of Greenville 
and its associated industry, and the unincorporated communities of 
Jamestown and New Harrisburg. Pymatuning Dam is owned by the State of 
Pennsylvania. Unit LS 3 is occupied by the species and contains all of 
the physical or biological features essential

[[Page 14824]]

to the conservation of the species. There is overlap of approximately 
14.5 river mi (23.4 km) of this unit with designated critical habitat 
for the federally threatened rabbitsfoot mussel (80 FR 24692; April 30, 
2015).
    Threats identified within Unit LS 3 include the 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, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
modifying dam releases from Pytmatuning Dam to mimic the natural 
hydrograph, and efforts to prevent the spread of invasive, nonnative 
species (see Special Management Considerations or Protection, above).

LS 4: Middle Island Creek

    Unit LS 4 partially overlaps with Unit RH 4 for the round 
hickorynut, described below. Unit LS 4 consists of 14 stream mi (23.7 
km) of Middle Island Creek in Doddridge and Tyler Counties, West 
Virginia, from the mouth of Meathouse Fork south of Smithburg, 
Doddridge County, downstream to its confluence with Arnold Creek at the 
Tyler/Doddridge County line. Riparian lands that border the unit 
include approximately 14 stream mi (23.5 km; 99 percent) in private 
ownership and 0.13 river mi (0.2 km; less than 1 percent) in public 
(local government) ownership. General land use on adjacent riparian 
lands and the surrounding HUC 8-level management unit includes forestry 
and the communities of Smithburg, Avondale, and West Union. Unit LS 4 
is occupied by the species and contains all of the physical or 
biological features essential to the conservation of the species.
    Threats identified within Unit LS 4 include degradation of habitat 
and water quality from impoundments, siltation and pollution due to 
improper timbering practices, resource extraction, water withdrawals, 
development, and wastewater treatment plants, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
actions to alleviate the threats of water quality and habitat 
degradation from hydrofracking wastewater discharges and impoundments 
downstream on the Ohio River, and efforts to prevent the spread of 
invasive, nonnative species (see Special Management Considerations or 
Protection, above).

LS 5: Little Kanawha River

    Unit LS 5 partially overlaps with Unit RH 5 for the round 
hickorynut, described below. Unit LS 5 consists of 123 river mi (198 
km) of the Little Kanawha River in Calhoun, Gilmer, Ritchie, and Wood 
Counties, West Virginia, from Burnsville Dam (which is in neighboring 
Braxton County) downstream to its confluence with the Ohio River in 
Parkersburg, Wood County, West Virginia. Riparian lands that border the 
unit include approximately 122 river mi (197.2 km; 99 percent) in 
private ownership and 0.53 river mi (0.9 km; less than 1 percent) in 
public (Federal or State government) ownership. General land use on 
adjacent riparian lands and the surrounding HUC 8-level management unit 
includes forestry, agriculture, industry, and numerous cities and 
municipalities. Burnsville Dam is operated by the U.S. Army Corps of 
Engineers. Unit LS 5 is occupied by the species and contains all of the 
physical or biological features essential to the conservation of the 
species.
    Threats identified within Unit LS 5 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatments plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include modifying dam releases from Burnsville Dam to mimic 
the natural hydrograph, and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

LS 6: Elk River

    Unit LS 6 is the same as Unit RH 6, described below for the round 
hickorynut. Unit LS 6 consists of 101 river mi (163 km) of the Elk 
River in Braxton, Clay, and Kanawha Counties, West Virginia, from 
Sutton Dam in Braxton County downstream to its confluence with the 
Kanawha River at Charleston, Kanawha County, West Virginia. Riparian 
lands that border the unit include approximately 93 river mi (150.3 km; 
92 percent) in private ownership and 7 river mi (12.7 km; 8 percent) in 
public (Federal, State, and local government) ownership. General land 
use on adjacent riparian lands and the surrounding HUC-8 level 
management unit includes forestry, agriculture, industry, and numerous 
cities and municipalities. Sutton Dam is operated by the U.S. Army 
Corps of Engineers. Unit LS 6 is occupied by the species and contains 
all of the physical or biological features essential to the 
conservation of the species. There is overlap of approximately 28 river 
mi (44.6 km) of this unit with designated critical habitat for the 
federally endangered diamond darter (78 FR 52364; August 22, 2013).
    Threats identified within Unit LS 6 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include modifying dam releases from Sutton Dam to mimic the 
natural hydrograph and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

LS 7: Kanawha River

    Unit LS 7 partially overlaps with Unit RH 7 for the round 
hickorynut, described below. Unit LS 7 consists of 21 river mi (33.9 
km) of the Kanawha River in Fayette and Kanawha Counties, West 
Virginia, from Kanawha Falls in Fayette County downstream to its 
confluence with Cabin Creek at Chelyan, Kanawha County, West Virginia. 
Riparian lands that border the unit include approximately 18 river mi 
(29.3 km; 90 percent) in private ownership and 2 river mi (4.6 km; 10 
percent) in public (Federal, State, and local government) ownership. 
General land use on adjacent riparian lands and the surrounding HUC 8-
level management unit includes forestry, agriculture, industry, and 
numerous cities and municipalities. London and Marmet locks and dams 
within this unit are operated by the U.S. Army Corps of Engineers. Unit 
LS 7 is occupied by the species and contains all of the physical or 
biological features essential to the conservation of the species.
    Threats identified within Unit LS 7 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include riparian vegetation re-establishment in addition to 
restoration efforts along shorelines to minimize sediment and 
contaminant inputs, and efforts to

[[Page 14825]]

prevent the spread of invasive, nonnative species (see Special 
Management Considerations or Protection, above).

LS 8: Licking River

    Unit LS 8 partially overlaps with Unit RH 8 for the round 
hickorynut, described below. Unit LS 8 consists of 181 river mi (291.5 
km) of the Licking River in Bath, Campbell, Fleming, Harrison, Kenton, 
Morgan, Nicholas, Pendleton, Robertson, and Rowan Counties, Kentucky, 
from Cave Run Dam in Bath/Rowan Counties downstream to its confluence 
with the Ohio River at Newport, Campbell/Kenton County, Kentucky. 
Riparian lands that border the unit include approximately 161 river mi 
(259.7 km; 90 percent) in private ownership and 19 river mi (31.7 km; 
10 percent) in public (Federal, State, and local government) ownership. 
General land use on adjacent riparian lands and the surrounding HUC 8-
level management unit includes forestry, agriculture industry, and 
numerous cities and municipalities. The Cave Run Dam is operated by the 
U.S. Army Corps of Engineers. Unit LS 8 is occupied by the species and 
contains all of the physical or biological features essential to the 
conservation of the species.
    Threats identified within Unit LS 8 include the degradation of 
habitat and water quality from impoundments and associated cold water 
discharges, siltation and pollution due to improper timbering 
practices, resource extraction, water withdrawals, development, and 
wastewater treatment plants, and the presence of invasive, nonnative 
species. Special management considerations or protection measures to 
reduce or alleviate the threats may include modifying dam releases from 
Cave Run Dam to mimic the natural hydrograph and efforts to prevent the 
spread of invasive, nonnative species (see Special Management 
Considerations or Protection, above).

LS 9: Green River

    Unit LS 9 partially overlaps with Unit RH 11 for the round 
hickorynut, described below. Unit LS 9 consists of 156 river mi (251.6 
km) of the Green River in Butler/Warren, Edmonson, Green, Hart, and 
Taylor Counties, Kentucky, from Green River Lake Dam south of 
Campbellsville in Taylor County downstream to its confluence with the 
Barren River at Woodbury, Warren/Butler County, Kentucky. Riparian 
lands that border the unit include approximately 105 river mi (169.2 
km; 67 percent) in private ownership and 51 river mi (82.4 km; 33 
percent) in public (Federal, State, and local government) ownership; 
Federal lands include a portion of Mammoth Cave National Park. General 
land use on adjacent riparian lands and the surrounding HUC 8-level 
management unit includes forestry, agriculture, industry, and numerous 
cities and municipalities, and Green River Lake Dam is operated by the 
U.S. Army Corps of Engineers. Unit LS 9 is occupied by the species and 
contains all of the physical or biological features essential to the 
conservation of the species. The entire approximately 156-river-mi 
(252-km) unit overlaps with designated critical habitat for the 
federally endangered diamond darter (78 FR 52364; August 22, 2013) and 
the federally threatened rabbitsfoot mussel (80 FR 24692; April 30, 
2015).
    Threats identified within Unit LS 9 include the degradation of 
habitat and water quality from impoundments and associated cold water 
discharges, siltation and pollution due to improper timbering and 
agricultural practices, resource extraction, water withdrawals, and 
development, all of which affect channel stability; wastewater 
treatment plants; and the presence of invasive, nonnative species. 
Special management considerations or protection measures may be needed 
to reduce or alleviate habitat degradation such as channelization and 
channel instability. Additional special management considerations or 
protection measures may be needed to address thermal and flow regimes 
associated with tail water releases from the Green River Lake Dam, and 
efforts to prevent the spread of invasive, nonnative species (see 
Special Management Considerations or Protection, above).

LS 10: Cumberland River

    Unit LS 10 consists of 48 river mi (77.5 km) of the Cumberland 
River in Smith, Trousdale, and Wilson Counties, Tennessee, from Cordell 
Hull Dam north of Carthage in Smith County downstream to reservoir 
influence of Old Hickory Reservoir at U.S. Route 231 north of Lebanon, 
Wilson County, Tennessee. Riparian lands that border the unit are all 
public (Federal) ownership. General land use on adjacent riparian lands 
and the surrounding HUC 8-level management unit includes forestry, 
agriculture, and the municipalities of Carthage and Rome, Tennessee; 
both Cordell Hull and Old Hickory Dams upstream and downstream of this 
unit are operated by the U.S. Army Corps of Engineers. Unit LS 10 is 
occupied by the species and contains all of the physical or biological 
features essential to the conservation of the species. There is overlap 
of approximately 1 river mi (1.7 km) of this unit with designated 
critical habitat for the federally endangered Short's bladderpod (79 FR 
50990; August 26, 2014).
    Threats identified within Unit LS 10 include the degradation of 
habitat and water quality from upstream and downstream impoundments and 
associated cold water discharges, siltation and pollution due to 
improper timbering practices, resource extraction, water withdrawals, 
development, and wastewater treatment plants, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
channel stability, thermal regimes, altered flow regimes associated 
with tail water releases from Cordell Hull Reservoir, actions to 
address channelization, and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

LS 11: Clinch River

    Unit LS 11 consists of 177 river mi (286.1 km) of the Clinch River 
in Russell, Scott, Tazewell, and Wise Counties in Virginia, and 
Claiborne, Hancock, and Hawkins Counties in Tennessee. This unit 
extends from Secondary Highway 637 west of Pounding Mill in Tazewell 
County, Virginia, downstream to County Highway 25, Claiborne County, 
Tennessee, northwest of Thorn Hill. The Tennessee portion of this unit 
is also encompassed by the Tennessee Wildlife Resources Agency's Clinch 
River Sanctuary. Riparian lands that border the unit include 
approximately 160 river mi (258.8 km; 90 percent) in private ownership 
and 17 river mi (27.3 km; 10 percent) in public (Federal and State) 
ownership. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit includes forestry, agriculture, 
industry, and numerous cities and municipalities. Unit LS 11 is 
occupied by the species and contains all of the physical or biological 
features essential to the conservation of the species. There is overlap 
of approximately 171 river mi (274.4 km) of this unit with designated 
critical habitat for the federally endangered purple bean, oyster 
mussel, rough rabbitsfoot, and Cumberlandian combshell (69 FR 53136; 
August 31, 2004); the federally endangered slabside pearlymussel and 
fluted kidneyshell (78 FR 59556; September 26, 2013); and with the 
federally threatened yellowfin madtom and slender chub (42 FR 45526; 
September 9, 1977).

[[Page 14826]]

    Threats identified within Unit LS 11 include the degradation of 
habitat and water quality from downstream impoundment, mining 
discharges, siltation and pollution due to improper timbering 
practices, resource extraction, water withdrawals, development, and 
wastewater treatment plants, and the presence of invasive, nonnative 
species. Special management considerations or protection measures to 
reduce or alleviate the threats may include management of the Norris 
Reservoir downstream to provide additional riverine habitat, and 
efforts to prevent the spread of invasive, nonnative species (see 
Special Management Considerations or Protection, above).

LS 12: Paint Rock River

    Unit LS 12 partially overlaps with Unit RH 12 for the round 
hickorynut, described below. Unit LS 12 consists of 58 river mi (94.5 
km) of the Paint Rock River in Jackson and Madison/Marshall Counties, 
Alabama, from the confluence of Hurricane Creek and Estill Fork in 
Jackson County, Alabama, downstream to its confluence with the 
Tennessee River west of Hebron, Madison/Marshall County, Alabama. 
Riparian lands that border the unit include approximately 2 river mi 
(4.1 km; 3 percent) in private ownership and 56 river mi (90.4 km; 97 
percent) in public (Federal and State) ownership. General land use on 
adjacent riparian lands and the surrounding HUC 8-level management unit 
includes forestry, agriculture, and several small municipalities 
(Princeton, Hollytree, Trenton, and Paint Rock). Unit LS 12 is occupied 
by the species and contains all of the physical or biological features 
essential to the conservation of the species. There is overlap of 
approximately 53 river mi (85 km) of this unit with designated critical 
habitat for the federally endangered slabside pearlymussel (78 FR 
59556; September 26, 2013) and the federally threatened rabbitsfoot 
mussel (80 FR 24692; April 30, 2015).
    Threats identified within Unit LS 12 include the degradation of 
habitat and water quality from downstream impoundment, siltation and 
pollution due to improper agricultural and timbering practices, 
resource extraction, water withdrawals, development, and wastewater 
treatment plants, and the presence of invasive, nonnative species. 
Special management considerations or protection measures to reduce or 
alleviate the threats may include management of Wheeler Reservoir 
downstream to provide additional riverine habitat, working with 
landowners to implement BMPs to reduce erosion and sedimentation 
associated with agricultural lands, and efforts to prevent the spread 
of invasive, nonnative species (see Special Management Considerations 
or Protection, above).

RH 1: Shenango River

    Unit RH 1 is the same as Unit LS 3 for the longsolid, described 
above. It consists of 22 river mi (35.5 km) of the Shenango River in 
Crawford County, Pennsylvania, from Pymatuning Dam downstream to the 
point of inundation by Shenango River Lake near Big Bend, Mercer 
County, Pennsylvania. Riparian lands that border the unit include 
approximately 15 river mi (24.3 km; 32 percent) in private ownership 
and 7 river mi (11.1 km; 68 percent) in public (Federal or State) 
ownership. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit includes the City of Greenville 
and its associated industry, and the unincorporated communities of 
Jamestown and New Harrisburg. Pymatuning Dam is owned by the State of 
Pennsylvania. Unit RH 1 is occupied by the species and contains all of 
the physical or biological features essential to the conservation of 
the species. There is overlap of approximately 14.5 river mi (23.4 km) 
of this unit with designated critical habitat for the federally 
threatened rabbitsfoot mussel (80 FR 24692; April 30, 2015).
    Threats identified within Unit RH 1 include the 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, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
modifying dam releases from Pytmatuning Dam to mimic the natural 
hydrograph, and efforts to prevent the spread of invasive, nonnative 
species (see Special Management Considerations or Protection, above).

RH 2: Grand River

    Unit RH 2 consists of 92 river mi (148.2 km) of the Grand River in 
Ashtabula, Lake, and Trumbull Counties, Ohio, from the Trumbull/Geauga 
County line south of Lake County, Ohio State Route 88, downstream to 
the mouth of the Grand River at its confluence with Lake Erie. Riparian 
lands that border the unit include approximately 59 river mi (95.2 km; 
64 percent) in private ownership and 33 river mi (53 km; 36 percent) in 
public (State and local government) ownership. The Grand River is a 
State Wild and Scenic River, with a ``Wild River'' designation for 
approximately 23 river mi (37 km) from the Harpersfield Covered Bridge 
downstream to the Norfolk and Western Railroad Trestle in Lake County, 
and ``Scenic River'' designation for approximately 33 river mi (53 km) 
from the U.S. 322 Bridge in Ashtabula County downstream to the 
Harpersfield Covered Bridge. General lands use on adjacent riparian 
lands and the surrounding HUC 8-level management unit includes 
forestry, agriculture, and several municipalities (West Farmington, 
Windsor, Rock Creek, and Perry). Harpersfield Dam is operated by the 
U.S. Army Corps of Engineers. Unit RH 2 is occupied by the species and 
contains all of the physical or biological features essential to the 
conservation of the species.
    Threats identified within Unit RH 2 include 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, nonnative 
species. Special management considerations or protection measures to 
reduce or alleviate the threats may include modifying dam releases from 
the Harpersfield Dam to mimic the natural hydrograph, and efforts to 
prevent the spread of invasive, nonnative species (see Special 
Management Considerations or Protection, above).

RH 3: Tippecanoe River

    Unit RH 3 consists of 75 river mi (120.8 km) of the Tippecanoe 
River in Fulton, Marshall, Pulaski, and Starke Counties, Indiana, from 
the railroad crossing west of the communities of Tippecanoe, Marshall 
County, downstream to the Pulaski/White County line, southwest of the 
community of Star City, Indiana. Riparian lands that border the unit 
include approximately 66 river mi (105.6 km; 89 percent) in private 
ownership and 9 river mi (14.5 km; 11 percent) in public ownership. 
General land use on adjacent riparian lands and the surrounding HUC 8-
level management unit includes agriculture and the communities of 
Tippecanoe, Pershing, and Ora. Unit RH 3 is occupied by the species and 
contains all of the physical or biological features essential to the 
conservation of the species. There is overlap of approximately 19 river 
mi (29.9 km) of this unit with designated critical habitat for the 
federally threatened rabbitsfoot mussel (80 FR 24692; April 30, 2015).
    Threats identified within Unit RH 3 include the degradation of 
habitat and

[[Page 14827]]

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, nonnative 
species. Special management considerations or protection measures to 
reduce or alleviate the threats may include modifying operations of 
downstream impoundments to provide additional riverine habitats, and 
efforts to prevent the spread of invasive, nonnative species (see 
Special Management Considerations or Protection, above).

RH 4: Middle Island Creek

    Unit RH 4 partially overlaps with Unit LS 4 for the longsolid, 
described above. Unit RH 4 consists of 75 stream mi (120.8 km) of the 
Middle Island Creek in Doddridge, Pleasants, and Tyler Counties, West 
Virginia, from the Tyler/Doddridge County line northeast of Deep Valley 
downstream to the confluence with the Ohio River, at St. Mary's, 
Pleasants County, West Virginia. Riparian lands that border the unit 
include approximately 74.8 stream mi (120.4 km; 99 percent) in private 
ownership and 0.2 stream mi (0.4 km; less than 1 percent) in public 
(Federal and State) ownership. General land use on adjacent riparian 
lands and the surrounding HUC 8-level management unit includes the 
communities of Smithburg, Avondale, West Union, Alma, and Centerville. 
Unit RH 4 is occupied by the species and contains all of the physical 
or biological features essential to the conservation of the species.
    Threats identified within Unit RH 4 include the degradation of 
habitat and water quality from siltation and pollution due to improper 
timbering practices, resource extraction, water withdrawals, 
development, and wastewater treatment plants, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
monitoring hydrofracking wastewater discharges and impoundments 
downstream on the Ohio River, and implementing efforts to prevent the 
spread of invasive, nonnative species (see Special Management 
Considerations or Protection, above).

RH 5: Little Kanawha River

    Unit RH 5 partially overlaps with Unit LS 5 for the longsolid, also 
described above. Unit RH 5 consists of 110 river mi (176.6 km) of the 
Little Kanawha River in Calhoun, Gilmer, Ritchie, and Wood Counties, 
West Virginia, from Burnsville Dam (which is in neighboring Braxton 
County) downstream to West Virginia Route 47 at Parkersburg, Wood 
County, West Virginia. Riparian lands that border the unit include 
approximately 109 river mi (175.4 km; 99 percent) in private ownership 
and 0.7 river mi (1.2 km; 1 percent) in public (Federal, State, and 
local government) ownership. General land use on adjacent riparian 
lands and the surrounding HUC 8-level management unit includes 
forestry, agriculture, industry, and numerous cities and 
municipalities. Burnsville Dam is operated by the U.S. Army Corps of 
Engineers. Unit RH 5 is occupied by the species and contains all of the 
physical or biological features essential to the conservation of the 
species.
    Threats identified within Unit RH 5 include the degradation of 
habitat from impoundments, siltation and pollution due to improper 
timbering practices, resource extraction, water withdrawals, 
development, and wastewater treatment plants, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
modifying dam releases from Burnsville Dam to mimics the natural 
hydrograph, and efforts to prevent the spread of invasive, nonnative 
species (see Special Management Considerations or Protection, above).

RH 6: Elk River

    Unit RH 6 is the same as Unit LS 6 for the longsolid, described 
above. Unit RH 6 consists of 101 river mi (163 km) of the Elk River in 
Braxton, Clay, and Kanawha Counties, West Virginia, from the Sutton Dam 
in Braxton County downstream to its confluence with the Kanawha River 
at Charleston, Kanawha County, West Virginia. Riparian lands that 
border the unit include approximately 93 river mi (150.3 km; 92 
percent) in private ownership and 7 river mi (12.7 km; 8 percent) in 
public (Federal, State, and local government) ownership. General land 
use on adjacent riparian lands and the surrounding HUC 8-level 
management unit includes forestry, agriculture, industry, and numerous 
cities and municipalities. Sutton Dam is operated by the U.S. Army 
Corps of Engineers. Unit RH 6 is occupied by the species and contains 
all of the physical or biological features essential to the 
conservation of the species. There is overlap of approximately 28 river 
mi (44.6 km) of this unit with the designated critical habitat for the 
federally endangered diamond darter (78 FR 52364; August 22, 2013).
    Threats identified within Unit RH 6 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include modifying dam releases from Sutton Dam to mimic the 
natural hydrograph, and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

RH 7: Kanawha River

    Unit RH 7 partially overlaps with Unit LS 7 for the longsolid, 
described above. Unit RH 7 consists of 37.5 river mi (60.4 km) of the 
Kanawha River in Fayette and Kanawha Counties, West Virginia, from 
Kanawha Falls in Fayette County downstream to its confluence with the 
Elk River at Charleston, Kanawha County, West Virginia. Riparian lands 
that border the unit include approximately 33 river mi (53.2 km; 90 
percent) in private ownership and 4 river mi (7.2 km; 10 percent) in 
public (Federal, State, and local government) ownership. General land 
use on adjacent riparian lands and the surrounding HUC 8-level 
management unit includes forestry, agriculture, industry, and numerous 
cities and municipalities. London and Marmet locks and dams within this 
unit are operated by the U.S. Army Corps of Engineers. Unit RH 7 is 
occupied by the species and contains all of the physical or biological 
features essential to the conservation of the species.
    Threats identified within Unit RH 7 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include riparian vegetation re-establishment in addition to 
restoration efforts along shorelines to minimize sediment and 
contaminant inputs, and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

RH 8: Licking River

    Unit RH 8 partially overlaps with Unit LS 8 for the longsolid, 
described above. Unit RH 8 consists of 150 mi (241.9 km) of the Licking 
River in Bath, Campbell, Fleming, Harrison, Kenton, Morgan,

[[Page 14828]]

Nicholas, Pendleton, Robertson, and Rowan Counties, Kentucky, from Cave 
Run Dam in Bath/Rowan Counties downstream to the Railroad crossing at 
the Campbell/Kenton/Pendleton County line at De Mossville, northwest of 
Butler, Pendleton County, Kentucky. Riparian lands that border the unit 
include approximately 131 river mi (211.8 km; 87 percent) in private 
ownership and 18 river mi (30 km; 13 percent) in public (Federal, 
State, and local government) ownership. General land use on adjacent 
riparian lands and the surrounding HUC 8-level management unit includes 
forestry, agriculture industry, and numerous cities and municipalities. 
Cave Run Dam is operated by the U.S. Army Corps of Engineers. Unit RH 8 
is occupied by the species and contains all of the physical or 
biological features essential to the conservation of the species.
    Threats identified within Unit RH 8 include the degradation of 
habitat and water quality from impoundments and associated cold water 
discharges, siltation and pollution due to improper timbering 
practices, resource extraction, water withdrawals, development, and 
wastewater treatment plants, and the presence of invasive, nonnative 
species. Special management considerations or protection measures to 
reduce or alleviate the threats may include modifying dam releases from 
Cave Run Dam to mimic the natural hydrograph, and efforts to prevent 
the spread of invasive, nonnative species (see Special Management 
Considerations or Protection, above).

RH 9: Rockcastle River

    Unit RH 9 consists of 15.3 river mi (24.6 km) of the Rockcastle 
River in Laurel, Pulaski, and Rockcastle Counties, Kentucky, from 
Kentucky Route 1956 at Billows downstream to Kentucky Route 192, near 
its confluence with Cane Creek along the Laurel/Pulaski County line, 
northwest of Baldrock, Laurel County, Kentucky. Riparian lands that 
border the unit include approximately 0.3 river mi (0.4 km; less than 1 
percent) in private ownership and 15 river mi (24.2 km; 99 percent) in 
public (Federal) ownership. Federal ownership is the Daniel Boone 
National Forest. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit is predominantly forestry. Unit 
RH 9 is occupied by the species and contains all of the physical or 
biological features essential to the conservation of the species. There 
is overlap of approximately 15 river mi (23.7 km) of this unit with 
designated critical habitat for the federally endangered fluted 
kidneyshell (78 FR 59556; September 26, 2013).
    Threats identified within Unit RH 9 include the degradation of 
habitat and water quality from siltation and pollution due to improper 
timbering practices and resource extraction, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
management of Lake Cumberland, located downstream, to provide more 
riverine habitat upstream, and efforts to prevent the spread of 
invasive, nonnative species (see Special Management Considerations or 
Protection, above).

RH 10: Buck Creek

    Unit RH 10 consists of 36 stream mi (58.1 km) of Buck Creek in 
Pulaski County, Kentucky, from its confluence with Glade Fork Creek 
northeast of Goochtown, downstream to its confluence with Whetstone 
Creek, northeast of Dykes, Pulaski County, Kentucky. Riparian lands 
that border the unit include approximately 33 stream mi (52.6 km; 92 
percent) in private ownership and 3 stream mi (5.5 km; 8 percent) in 
public (State and local government) ownership. General land use on 
adjacent riparian lands and the surrounding HUC 8-level management unit 
includes forestry, agriculture, and several small communities. Unit RH 
10 is occupied by the species and contains all of the physical or 
biological features essential to the conservation of the species. There 
is overlap of approximately 35 stream mi (56.7 km) with designated 
critical habitat for the federally endangered Cumberlandian combshell 
and oyster mussel (69 FR 53136; August 31, 2004), and the federally 
endangered fluted kidneyshell (78 FR 59556; September 26, 2013).
    Threats identified within Unit RH 10 include the degradation of 
habitat and water quality from instream gravel mining, forest clearing 
activities, illegal off-road vehicle use, nonpoint source pollution 
from agriculture, and development activities, and the presence of 
invasive, nonnative species. Special management considerations or 
protection measures to reduce or alleviate the threats may include 
management of Lake Cumberland, located downstream, to provide more 
riverine habitat upstream, and efforts to prevent the spread of 
invasive, nonnative species (see Special Management Considerations or 
Protection, above).

RH 11: Green River

    Unit RH 11 partially overlaps with Unit LS 9 for the longsolid, 
described above. Unit RH 11 consists of 98 river mi (157.7 km) of the 
Green River in Butler/Warren, Edmonson, Green, and Hart Counties, 
Kentucky, from the mouth of Lynn Camp Creek east of Linwood in Hart 
County downstream to its confluence with the Barren River at Woodbury, 
Warren/Butler Counties, Kentucky. Riparian lands that border the unit 
include approximately 61 river mi (98.4 km; 62 percent) in private 
ownership and 37 river mi (59.4 km; 38 percent) in public (Federal and 
State) ownership; Federal lands include a portion of Mammoth Cave 
National Park. General land use on adjacent riparian lands and the 
surrounding HUC 8-level management unit includes forestry, agriculture, 
industry, and numerous cities and municipalities, and Green River Lake 
Dam (located upstream of this unit) is operated by the U.S. Army Corps 
of Engineers. Unit RH 11 is occupied by the species and contains all of 
the physical or biological features essential to the conservation of 
the species. The entire 98-river-mi (157.7-km) unit overlaps with 
designated critical habitat for the federally endangered diamond darter 
(78 FR 52364; August 22, 2013) and the federally threatened rabbitsfoot 
mussel (80 FR 24692; April 30, 2015).
    Threats identified within Unit RH 11 include the degradation of 
habitat and water quality from Green River Lake Dam and associated cold 
water discharges, siltation and pollution due to improper timbering and 
agricultural practices, resource extraction, water withdrawals, and 
development, all of which affect channel stability; wastewater 
treatment plants; and the presence of invasive, nonnative species. 
Special management considerations or protection measures may be needed 
to reduce or alleviate habitat degradation such as channelization and 
channel instability. Additional special management considerations or 
protection measures may be needed to address thermal and flow regimes 
associated with tail water releases from the Green River Lake Dam, and 
efforts to prevent the spread of invasive, nonnative species (see 
Special Management Considerations or Protection, above).

RH 12: Paint Rock River

    Unit RH 12 partially overlaps with Unit LS 12 for the longsolid, 
described above. Unit RH 12 consists of 48 river mi (77.5 km) of the 
Paint Rock River in Jackson and Madison/Marshall

[[Page 14829]]

Counties, Alabama, from the confluence of Hurricane Creek and Estill 
Fork in Jackson County, Alabama, downstream to U.S. Route 431, south of 
New Hope, Madison/Marshall Counties, Alabama. Riparian lands that 
border the unit include approximately 2 river mi (4.1 km; 2 percent) in 
private ownership and 46 river mi (73.4 km; 98 percent) in public 
(Federal and State) ownership. General land use on adjacent riparian 
lands and the surrounding HUC 8-level management unit includes 
forestry, agriculture, and several small municipalities (Princeton, 
Hollytree, Trenton, and Paint Rock). Unit RH 12 is occupied by the 
species and contains all of the physical or biological features 
essential to the conservation of the species. The entire approximately 
48-river-mi (77.5-km) unit overlaps with designated critical habitat 
for the federally endangered slabside pearlymussel (78 FR 59556; 
September 26, 2013), and the federally threatened rabbitsfoot mussel 
(80 FR 24692; April 30, 2015).
    Threats identified within Unit RH 12 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, resource extraction, water 
withdrawals, development, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include management of Wheeler Reservoir downstream to 
provide additional riverine habitat, working with landowners to 
implement BMPs to reduce erosion and sedimentation associated with 
agricultural lands, and efforts to prevent the spread of invasive, 
nonnative species (see Special Management Considerations or Protection, 
above).

RH 13: Duck River

    Unit RH 13 consists of 59 river mi (94.8 km) of the Duck River in 
Bedford, Marshall, and Maury Counties, Tennessee, from its confluence 
with Sinking Creek in Bedford County, downstream to the mouth of Goose 
Creek, east of Columbia, Maury County, Tennessee. Riparian lands that 
border the unit include approximately 27 river mi (43.7 km; 47 percent) 
in private ownership and 32 river mi (51.1 km; 53 percent) in public 
(State and local government) ownership. General land use on adjacent 
riparian lands and the surrounding HUC 8-level management unit includes 
forestry, agriculture, and several municipalities (Milltown, Leftwich, 
and Philadelphia). Normandy Dam is operated by the Tennessee Valley 
Authority. Unit RH 13 is occupied by the species and contains all of 
the physical or biological features essential to the conservation of 
the species. There is overlap of approximately 55 river mi (88.9 km) of 
this unit with designated critical habitat for the federally endangered 
slabside pearlymussel and fluted kidneyshell (78 FR 59556; September 
26, 2013), and the federally endangered Cumberlandian combshell and 
oyster mussel (69 FR 53136; August 31, 2004).
    Threats identified within Unit RH 13 include the degradation of 
habitat and water quality from impoundments, siltation and pollution 
due to improper timbering practices, agricultural activities 
(livestock), row crop agriculture and channelization, resource 
extraction, water withdrawals, and wastewater treatment plants, and the 
presence of invasive, nonnative species. Special management 
considerations or protection measures to reduce or alleviate the 
threats may include seasonally adjusted flow regimes associated with 
tail water releases from Normandy Dam, working with landowners to 
implement BMPs to reduce erosion and sedimentation associated with 
agricultural lands, planting adequate riparian buffers to minimize 
agriculture impacts, and implementing efforts to prevent the spread of 
invasive, nonnative species (see Special Management Considerations or 
Protection, above).

RH 14: Big Black River

    Unit RH 14 consists of 4 river mi (7 km) of the Big Black River in 
Montgomery County, Mississippi, from its confluence with Poplar Creek 
in Montgomery County, downstream to its confluence with Lewis Creek, 
Mississippi. Riparian lands that border the unit are all (100 percent) 
in private ownership. General land use on adjacent riparian lands and 
the surrounding HUC 8-level management unit is predominantly 
agricultural activities. Unit RH 14 is occupied by the species and 
contains all of the physical or biological features essential to the 
conservation of the species.
    Threats identified within Unit RH 14 include degradation of habitat 
and water quality from impoundments, siltation and pollution due to 
improper agricultural activities, row crop agriculture and 
channelization, and water withdrawals, and the presence of invasive, 
nonnative species. Special management considerations or protection 
measures to reduce or alleviate the threats may include working with 
landowners to implement BMPs to reduce erosion and sedimentation 
associated with agricultural lands and water quality degradation, and 
efforts to prevent the spread of invasive, nonnative species (see 
Special Management Considerations or Protection, above).

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species.
    We published a final rule revising the definition of destruction or 
adverse modification on August 27, 2019 (84 FR 44976). Destruction or 
adverse modification means a direct or indirect alteration that 
appreciably diminishes the value of critical habitat as a whole for the 
conservation of a listed species.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are actions on State, Tribal, local, or 
private lands that require a Federal permit (such as a permit from the 
U.S. Army Corps of Engineers under section 404 of the Clean Water Act 
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10 
of the Act) or that involve some other Federal action (such as funding 
from the Federal Highway Administration, Federal Aviation 
Administration, or the Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat, and actions 
on State, Tribal, local, or private lands that are not federally 
funded, authorized, or carried out by a Federal agency--do not require 
section 7 consultation.
    Compliance with the requirements of section 7(a)(2) is documented 
through our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect, and 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species and/or 
destroy or adversely modify critical habitat, we provide reasonable and 
prudent

[[Page 14830]]

alternatives to the project, if any are identifiable, that would avoid 
the likelihood of jeopardy and/or destruction or adverse modification 
of critical habitat. We define ``reasonable and prudent alternatives'' 
(at 50 CFR 402.02) as alternative actions identified during 
consultation that:
    (1) Can be implemented in a manner consistent with the intended 
purpose of the action,
    (2) Can be implemented consistent with the scope of the Federal 
agency's legal authority and jurisdiction,
    (3) Are economically and technologically feasible, and
    (4) Would, in the Service Director's opinion, avoid the likelihood 
of jeopardizing the continued existence of the listed species and/or 
avoid the likelihood of destroying or adversely modifying critical 
habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    Regulations at 50 CFR 402.16 set forth requirements for Federal 
agencies to reinitiate formal consultation on previously reviewed 
actions. These requirements apply when the Federal agency has retained 
discretionary involvement or control over the action (or the agency's 
discretionary involvement or control is authorized by law) and, 
subsequent to the previous consultation: (1) if the amount or extent of 
taking specified in the incidental take statement is exceeded; (2) if 
new information reveals effects of the action that may affect listed 
species or critical habitat in a manner or to an extent not previously 
considered; (3) if the identified action is subsequently modified in a 
manner that causes an effect to the listed species or critical habitat 
that was not considered in the biological opinion or written 
concurrence; or (4) if a new species is listed or critical habitat 
designated that may be affected by the identified action.
    In such situations, Federal agencies sometimes may need to request 
reinitiation of consultation with us, but Congress also enacted some 
exceptions in 2018 to the requirement to reinitiate consultation on 
certain land management plans on the basis of a new species listing or 
new designation of critical habitat that may be affected by the subject 
Federal action. See 2018 Consolidated Appropriations Act, Public Law 
115-141, Div, O, 132 Stat. 1059 (2018).
    Overall, and as stated above under Final Critical Habitat 
Designation, the majority of units overlap in part or whole with 
existing critical habitat designated for other federally endangered 
aquatic species (i.e., diamond darter, Short's bladderpod, purple bean, 
rough rabbitsfoot, Cumberlandian combshell, oyster mussel, slabside 
pearlymussel, and fluted kidneyshell) or federally threatened aquatic 
species (i.e., rabbitsfoot, yellowfin madtom, and slender chub). The 
conservation measures we would recommend for the longsolid and round 
hickorynut are likely to be the same or very similar to those we 
already recommend for these other listed aquatic species.

Application of the ``Adverse Modification'' Standard

    The key factor related to the destruction or adverse modification 
determination is whether implementation of the proposed Federal action 
directly or indirectly alters the designated critical habitat in a way 
that appreciably diminishes the value of the critical habitat as a 
whole for the conservation of the listed species. As discussed above, 
the role of critical habitat is to support physical or biological 
features essential to the conservation of a listed species and provide 
for the conservation of the species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may violate section 
7(a)(2) of the Act by destroying or adversely modifying such habitat, 
or that may be affected by such designation.
    Activities that we may, during a consultation under section 7(a)(2) 
of the Act, consider likely to destroy or adversely modify critical 
habitat include, but are not limited to actions that would: (1) Alter 
the geomorphology of their stream and river habitats (e.g., instream 
excavation or dredging, impoundment, channelization, sand and gravel 
mining, clearing riparian vegetation, and discharge of fill materials); 
(2) significantly alter the existing flow regime where these species 
occur (e.g., impoundment, urban development, water diversion, water 
withdrawal, water draw-down, and hydropower generation); (3) 
significantly alter water chemistry or water quality (e.g., hydropower 
discharges, or the release of chemicals, biological pollutants, or 
heated effluents into surface water or connected groundwater at a point 
source or by dispersed release (nonpoint source)); and (4) 
significantly alter stream bed material composition and quality by 
increasing sediment deposition or filamentous algal growth (e.g., 
construction projects, gravel and sand mining, oil and gas development, 
coal mining, livestock grazing, timber harvest, and other watershed and 
floodplain disturbances that release sediments or nutrients into the 
water). Consulting agencies and such activities could include, but are 
not limited to:
    (1) U.S. Army Corps of Engineers (channel dredging and maintenance; 
dam projects including flood control, navigation, hydropower, and water 
supply; and Clean Water Act permitting including bridge projects and 
stream restoration activities).
    (2) U.S. Department of Agriculture, including the Natural Resources 
Conservation Service and Farm Service Agency (technical and financial 
assistance for projects) and the Forest Service (aquatic habitat 
restoration, fire management plans, fire suppression, fuel reduction 
treatments, forest plans, and mining permits).
    (3) U.S. Department of Energy (renewable and alternative energy 
projects).
    (4) Federal Energy Regulatory Commission (interstate pipeline 
construction and maintenance, dam relicensing, and hydrokinetics).
    (5) U.S. Department of Transportation (highway and bridge 
construction and maintenance).
    (6) U.S. Fish and Wildlife Service (issuance of section 10 permits 
for enhancement of survival, habitat conservation plans, and safe 
harbor agreements; Partners for Fish and Wildlife program projects 
benefiting these species or other listed species; and Wildlife and 
Sportfish Restoration program sportfish stocking).
    (7) Environmental Protection Agency (water quality criteria and 
permitting).
    (8) Tennessee Valley Authority (flood control, navigation, 
hydropower, and land management for the Tennessee River system).
    (9) Office of Surface Mining Reclamation and Enforcement (land 
resource management plans, mining permits, oil and natural gas permits, 
abandoned mine land projects, and renewable energy development).
    (10) National Park Service (land management plans and permitting).

Exemptions

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

    Section 4(a)(3)(B)(i) of the Act (16 U.S.C. 1533(a)(3)(B)(i)) 
provides that the Secretary shall not designate as critical habitat any 
lands or other geographical areas owned or controlled by the

[[Page 14831]]

Department of Defense (DoD), or designated for its use, that are 
subject to an integrated natural resources management plan (INRMP) 
prepared under section 101 of the Sikes Act Improvement Act of 1997 (16 
U.S.C. 670a), if the Secretary determines in writing that such plan 
provides a benefit to the species for which critical habitat is 
proposed for designation. There are no DoD lands with a completed INRMP 
within the critical habitat designation.

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

    Section 4(b)(2) of the Act states that the Secretary shall 
designate and make revisions to critical habitat on the basis of the 
best available scientific data after taking into consideration the 
economic impact, national security impact, and any other relevant 
impact of specifying any particular area as critical habitat. The 
Secretary may exclude an area from critical habitat based on economic 
impacts, impacts on national security, or any other relevant impacts. 
Exclusion decisions are governed by the regulations at 50 CFR 424.19 
and the Policy Regarding Implementation of Section 4(b)(2) of the 
Endangered Species Act, 81 FR 7226 (Feb. 11, 2016) (2016 Policy)--both 
of which were developed jointly with the National Marine Fisheries 
Service (NMFS). We also refer to a 2008 Department of the Interior 
Solicitor's opinion entitled ``The Secretary's Authority to Exclude 
Areas from a Critical Habitat Designation under Section 4(b)(2) of the 
Endangered Species Act'' (M-37016). We explain each decision to exclude 
areas, as well as decisions not to exclude, to demonstrate that the 
decision is reasonable.
    The Secretary may exclude any particular area if she determines 
that the benefits of such exclusion outweigh the benefits of including 
such area as part of the critical habitat, unless she determines, based 
on the best scientific data available, that the failure to designate 
such area as critical habitat will result in the extinction of the 
species. In making the determination to exclude a particular area, the 
statute on its face, as well as the legislative history, are clear that 
the Secretary has broad discretion regarding which factor(s) to use and 
how much weight to give to any factor. In this final rule, we are not 
excluding any areas from critical habitat.

Exclusions Based on Economic Impacts

    Section 4(b)(2) of the Act and its implementing regulations require 
that we consider the economic impact that may result from a designation 
of critical habitat. In order to consider economic impacts, we prepared 
an incremental effects memorandum (IEM) and screening analysis which, 
together with our narrative and interpretation of effects, we consider 
our economic analysis of the critical habitat designation and related 
factors (Service 2020, entire). The analysis, dated March 19, 2020, was 
made available for public review from September 29, 2020, through 
December 28, 2020 (Industrial Economics, Inc. 2020, entire). The 
economic analysis addressed probable economic impacts of critical 
habitat designation for the longsolid and round hickorynut. Following 
the close of the comment period, we reviewed and evaluated all 
information submitted during the comment period that may pertain to our 
consideration of the probable incremental economic impacts of this 
critical habitat designation. Additional information relevant to the 
probable incremental economic impacts of critical habitat designation 
for the longsolid and round hickorynut is summarized below and 
available in the screening analysis for the longsolid and round 
hickorynut (Industrial Economics, Inc. 2020, entire), available at 
https://www.regulations.gov.
    Executive Orders (E.O.s) 12866 and 13563 direct Federal agencies to 
assess the costs and benefits of available regulatory alternatives in 
quantitative (to the extent feasible) and qualitative terms. Consistent 
with the E.O. regulatory analysis requirements, our effects analysis 
under the Act may take into consideration impacts to both directly and 
indirectly affected entities, where practicable and reasonable. If 
sufficient data are available, we assess, to the extent practicable, 
the probable impacts to both directly and indirectly affected entities. 
As part of our screening analysis, we considered the types of economic 
activities that are likely to occur within the areas likely affected by 
the critical habitat designation. In our evaluation of the probable 
incremental economic impacts that may result from the designation of 
critical habitat for the longsolid and round hickorynut, first we 
identified, in the IEM dated February 13, 2020 (Service 2020, entire), 
probable incremental economic impacts associated with the following 
categories of activities: instream excavation or dredging; 
impoundments; channelization; sand and gravel mining; clearing riparian 
vegetation; discharge of fill materials; urban development; water 
diversion; water withdrawal; water draw-down; hydropower generation and 
discharges; release of chemicals, biological pollutants, or heated 
effluents into surface water or connected ground water at a point 
source or by dispersed release (nonpoint); construction projects; oil 
and gas development; coal mining; livestock grazing; timber harvest; 
and other watershed or floodplain activities that release sediments or 
nutrients into the water. We considered each industry or category 
individually. Additionally, we considered whether their activities have 
any Federal involvement.
    Critical habitat designation generally will not affect activities 
that do not have any Federal involvement; under the Act, the 
designation of critical habitat only affects activities conducted, 
funded, permitted, or authorized by Federal agencies. In areas where 
the longsolid or round hickorynut are present, Federal agencies are 
required to consult with the Service under section 7 of the Act on 
activities they fund, permit, or implement that may affect the species. 
Consultations to avoid the destruction or adverse modification of 
critical habitat will be incorporated into the existing consultation 
process.
    In our IEM, we attempted to clarify the distinction between the 
effects that would result from the species being listed and those 
attributable to the critical habitat designation (i.e., difference 
between the jeopardy and adverse modification standards) for the 
longsolid's and round hickorynut's critical habitat. Because we are 
designating critical habitat for the longsolid and round hickorynut 
concurrently with listing the species, it has been our experience that 
it is more difficult to discern which conservation efforts are 
attributable to the species' being listed and those which will result 
solely from the designation of critical habitat; this is particularly 
difficult where there is no unoccupied critical habitat and, thus, 
there will be consultations for all areas based on the species' 
presence in those areas. However, the following specific circumstances 
in this case help to inform our evaluation: (1) The essential physical 
or biological features identified for critical habitat are the same 
features essential for the life requisites of the species, and (2) any 
actions that would result in sufficient harm or harassment to 
constitute jeopardy to the longsolid or round hickorynut would also 
likely adversely affect the essential physical or biological features 
of critical habitat. The IEM outlines our rationale concerning this 
limited distinction between baseline conservation efforts and 
incremental impacts of the designation of critical habitat for this 
species. This evaluation of the

[[Page 14832]]

incremental effects has been used as the basis to evaluate the probable 
incremental economic impacts of this designation of critical habitat.
    The final critical habitat designation for the longsolid includes 
12 units, all of which are occupied by the species. Ownership of 
riparian lands adjacent to the units includes 810 river mi (1,304 km; 
74 percent) in private ownership and 305 river mi (491 km; 26 percent) 
in public (Federal, State, or local government) ownership. The final 
critical habitat designation for the round hickorynut includes 14 
units, all of which are occupied by the species. Ownership of riparian 
lands adjacent to the units includes 709 river mi (1,141 km; 77 
percent) in private ownership and 212 river mi (341 km; 23 percent) in 
public (Federal, State, or local government) ownership.
    Total incremental costs of critical habitat designation for the 
longsolid and round hickorynut are anticipated to be approximately 
$327,000 (2020 dollars) per year for the next 10 years. The costs are 
reflective of the critical habitat area (i.e., 1,115 river mi (1,794 
km) for the longsolid and 921 river mi (1,482 km) for the round 
hickorynut (some of which overlap each other)), the presence of the 
species (i.e., occupied) in these areas, and the presence of other 
federally listed species and designated critical habitats. Since 
consultation is already required in these areas as a result of the 
presence of other listed species and critical habitats and will be 
required as a result of the listing of the longsolid and round 
hickorynut, the economic costs of the critical habitat designation will 
likely be primarily limited to additional administrative efforts to 
consider adverse modification for these two species in section 7 
consultations. In total, 159 section 7 consultation actions 
(approximately 3 formal consultations, 114 informal consultations, and 
38 technical assistance efforts) are anticipated to occur annually in 
designated critical habitat areas. Critical habitat may also trigger 
additional regulatory changes. For example, the designation may cause 
other Federal, State, or local permitting or regulatory agencies to 
expand or change standards or requirements. Regulatory uncertainty 
generated by critical habitat may also have impacts. For example, 
landowners or buyers may perceive that the rule restricts land or water 
use activities in some way and, therefore, value the use of the land 
less than they would have absent critical habitat.
    We solicited data and comments from the public regarding the 
economic analysis, as well as all aspects of the September 29, 2020 (85 
FR 61384), proposed rule. We did not receive any additional information 
on economic impacts during the public comment period to determine 
whether any specific areas should be excluded from the final critical 
habitat designation under authority of the Act's section 4(b)(2) and 
our implementing regulations at 50 CFR 424.19.
    As discussed above, we considered the economic impacts of the 
critical habitat designation, the Secretary is not exercising her 
discretion to exclude any areas from this designation of critical 
habitat for the longsolid and round hickorynut based on economic 
impacts.
    A copy of the IEM and screening analysis with supporting documents 
may be obtained by contacting the Asheville Ecological Services Field 
Office (see FOR FURTHER INFORMATION CONTACT) or by downloading from the 
internet at https://www.regulations.gov.

Exclusions Based on Impacts on National Security and Homeland Security

    In preparing this rule, we determined that there are no lands 
within the designated critical habitat for the longsolid or round 
hickorynut that are owned or managed by the DoD or Department of 
Homeland Security, and, therefore, we anticipate no impact on national 
security or homeland security. We did not receive any additional 
information during the public comment period for the proposed 
designation regarding impacts of the designation on national security 
or homeland security that would support excluding any specific areas 
from the final critical habitat designation under authority of section 
4(b)(2) and our implementing regulations at 50 CFR 424.19, as well as 
the 2016 Policy.

Exclusions Based on Other Relevant Impacts

    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts on national 
security as discussed above. To identify other relevant impacts that 
may affect the exclusion analysis, we consider a number of factors, 
including whether there are permitted conservation plans covering the 
species in the area such as HCPs, safe harbor agreements, or candidate 
conservation agreements with assurances, or whether there are non-
permitted conservation agreements and partnerships that would be 
encouraged by designation of, or exclusion from, critical habitat. In 
addition, we look at whether Tribal conservation plans or partnerships, 
Tribal resources, or government-to-government relationships of the 
United States with Tribal entities may be affected by the designation. 
We also consider any State, local, social, or other impacts that might 
occur because of the designation.
    We are not excluding any areas from critical habitat. In preparing 
this final rule, we have determined that there are currently no HCPs or 
other management plans for the longsolid and round hickorynut, and the 
designation does not include any Tribal lands or trust resources. We 
anticipate no impact on Tribal lands, partnerships, or HCPs from this 
final critical habitat designation. We did not receive any additional 
information during the public comment period for the proposed rule 
regarding other relevant impacts to support excluding any specific 
areas from the final critical habitat designation under authority of 
section 4(b)(2) and our implementing regulations at 50 CFR 424.19, as 
well as the 2016 Policy. Accordingly, the Secretary is not exercising 
her discretion to exclude any areas from this designation based on 
other relevant impacts.

Summary of Comments and Recommendations

    In the proposed rule published on September 29, 2020 (85 FR 61384), 
we requested that all interested parties submit written comments on the 
proposal by December 28, 2020. We also contacted appropriate Federal 
and State agencies, 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 the 
USA Today legal notice section on September 30, 2020. Although we 
invited requests for a public hearing in the proposed rule, 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 determination or is addressed below.

Peer Reviewer Comments

    As discussed in Peer Review above, we received comments from three 
specialists for the longsolid (which informed the SSA report and this 
final rule), and no responses for the round hickorynut. We reviewed all 
comments we received from the peer reviewers for substantive issues and 
new information regarding the information contained in the longsolid's 
SSA report. The peer reviewers generally concurred with our methods and 
conclusions, and provided additional information, clarifications, and 
suggestions to improve the final

[[Page 14833]]

SSA report. Peer reviewer comments were incorporated into the SSA 
report and this final rule as appropriate.

State Agency Comments

    We received comments from agencies in six States: Michigan, Ohio, 
Pennsylvania, West Virginia, North Carolina, and Mississippi.
    (1) Comment: The Michigan Department of Natural Resources (DNR) 
requested that we not list the longsolid as an endangered species in 
the State of Michigan, and that we postpone listing the round 
hickorynut as an endangered species until additional information 
concerning their distribution and status is available. Additionally, 
the Michigan DNR requested we partner with them to conduct additional 
surveys in Michigan to evaluate the current population status of the 
round hickorynut due to information gaps for this species in Michigan.
    Our Response: The longsolid does not occur in Michigan, nor are 
there any historical records for the State; therefore, we did not 
propose to list, and are not listing in this rule, the longsolid within 
the State of Michigan. We agree that there is limited information 
available for round hickorynut in Michigan; however, we must make a 
decision based the best available scientific and commercial 
information. Accordingly, our analysis of the best available data 
indicates that the species meets the definition of a threatened species 
under the Act (see Determination of Status for the Longsolid and Round 
Hickorynut, above). We support the State conducting additional surveys 
due to its status as a ``State trust species,'' and we will continue to 
coordinate with Michigan DNR to ensure that the best available 
information is also used for any future conservation actions.
    (2) Comment: The State of West Virginia recommended that the 
Kanawha River be included in the discussion of transportation threats 
regarding barge traffic given it is navigable and subject to barge 
traffic activity.
    Our Response: The Kanawha River is incorporated by reference (i.e., 
the listed populations in this section of the proposed rule include 
Taylor (1983b, p. 5)), which is a mussel survey of the Kanawha River. 
Our intent was that the threat discussion of transportation include all 
major river basins (HUC 2 level), which includes the Kanawha River, 
where the longsolid is extant.
    (3) Comment: The State of West Virginia recommended that Unit RH 4 
(Middle Island Creek) include Meathouse Fork, which is a major 
tributary of Middle Island Creek. The State indicated that West 
Virginia DNR surveys have found greater numbers of round hickorynut in 
Meathouse Fork than in the whole of the Elk River.
    Our Response: Meathouse Fork, although occupied by the round 
hickorynut, was not proposed as critical habitat and is not designated 
as critical habitat in this rule. We have determined that the ``core'' 
population in Middle Island Creek is sufficient to maintain resiliency 
in the watershed, as it is considered a stronghold population (which 
was part of the criteria for critical habitat selection). At this time, 
the Meathouse Fork population exhibits low resiliency and is subject to 
a high level of threats, such as contaminant spills, as discussed under 
Threats Analysis, above. We determined it does not contain the physical 
or biological features essential for the conservation of the species 
and, therefore, does not meet the definition of critical habitat.
    (4) Comment: The State of Ohio stated that listing these species 
will increase their costs for complying with the Act and the National 
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), mainly through 
increased species surveys, the costs associated with formal 
consultations (the production of biological assessments), and possible 
costs associated with project delays due to the length of time to 
conduct formal consultation versus informal consultation. The State 
indicated that due to listing the round hickorynut, it will be 
necessary to conduct two additional survey efforts and two possible 
formal consultations per year on average. The State asserts these 
formal consultations will add approximately $100,000-$200,000 per year 
in project costs, potentially increasing the State's compliance costs 
by 4 percent per year.
    Our Response: The Act requires the Secretary to base listing 
determinations solely on the best scientific and commercial data 
available; thus, we cannot factor in possible economic costs into a 
decision to list a species. However, we acknowledge that listing either 
species could result in additional costs to the State to comply with 
the Act, and potentially other laws, given the protections that are 
afforded listed species. Separately, we are required to consider 
economic costs for designating critical habitat. As such, the economic 
analysis for the longsolid and round hickorynut focuses on the 
incremental impact of the critical habitat designation. The economic 
analysis conducted for the critical habitat designation uses the rate 
of past consultations conducted on similar listed aquatic species that 
occur within the critical habitat areas to forecast the rate of future 
section 7 consultations that may occur for the longsolid and round 
hickorynut (IEc 2020, entire; Service 2020, entire). Critical habitat 
designation is not anticipated to result in additional conservation 
efforts being included as part of section 7 consultations beyond what 
would have already been required absent critical habitat designation.
    (5) Comment: The State of Ohio commented that although listing 
round hickorynut is logical, they are concerned and disagree with 
designating critical habitat in the Grand River through the shipping 
channel. Further, they stated that the shipping channel portion of the 
Grand River is regularly dredged to provide access to Lake Erie, and 
the dredging has resulted in stream channel modifications for marinas 
and docks.
    Our Response: We agree that the Grand River has experienced human-
caused modifications over time. However, the Grand River population of 
round hickorynut is considered one of only two stronghold management 
units that remain, and the best available information indicates that 
the shipping channel portion of the river is occupied. Further, because 
the round hickorynut appears to have adapted to conditions at river 
outflows and along shorelines of impoundments (e.g., Lake St. Clair), 
we find it is important at this time that the lower Grand River 
maintains some level of connectivity with other Lake Erie tributaries, 
such as the Black River in Ohio, and the Belle, Black, and Pine Rivers 
in Michigan.
    The Grand River Unit (RH 2) is the only critical habitat unit 
designated for the round hickorynut in the Great Lakes basin. This area 
was once fully connected to Lake Erie, which allowed connectivity with 
other river tributary systems. The Grand River population, occurring 
within this unit, is important because it currently has high 
resiliency, it contains the only documented recruiting population in 
the Great Lakes basin, and the round hickorynut occurs throughout the 
river. Accordingly, we determined this unit contains features that are 
essential to the conservation of the species and that may require 
special management considerations or protection and, therefore, that it 
meets the definition of critical habitat.
    (6) Comment: The State of Mississippi (Mississippi Forestry 
Association) requested that we take into consideration the State's BMP 
compliance rate for certified forest lands when evaluating information 
for the

[[Page 14834]]

round hickorynut, specifically for SMZs.
    The comment states that BMPs are nonregulated, voluntary guidelines 
for silviculture activities that, when properly applied, will protect 
water quality from non-point source pollutants while maintaining site 
productivity. Further, the comment noted that the 2019 BMP 
Implementation Survey (implemented on a 3-year cycle by the Mississippi 
Forestry Commission) revealed that 95.3 percent of the applicable BMPs 
were implemented. The Statewide compliance of the survey was determined 
to be 95 percent at the 95 percent confidence level. The comment 
asserts that the SMZs benefit the mussels by protecting water quality 
through filtering nutrients and trapping sediments, regulating water 
temperature, and acting as a protective barrier around the body of 
water to limit activity near the channel.
    Our Response: We did take into consideration the Mississippi BMP 
compliance rate in SMZs. However, only one population of round 
hickorynut occurs within Mississippi, and it is currently in low 
condition. The Mississippi BMPs are nonregulated, voluntary guidelines 
for silviculture activities. We recognize the high compliance rates of 
BMPs on State-certified forest lands and we have incorporated an 
exception under the section 4(d) rule for silvicultural activities that 
implement state-approved BMPs.
    (7) Comment: The State of Mississippi (Mississippi Forestry 
Association) stated that they interpret the critical habitat 
designation to include the river channel, and they requested 
clarification that the lands adjacent to the stream bank are not 
included in the critical habitat designation.
    Our Response: The State of Mississippi's interpretation is correct. 
Lands adjacent to the stream bank are not included in the critical 
habitat designation, although certain activities on lands adjacent to 
occupied streams can influence the resource needs of the listed species 
that occurs within the river (e.g., increased sediments from activities 
on adjacent lands could reduce water quality).

Public Comments--Economics

    (8) Comment: One commenter stated that the benefits of excluding 
the proposed areas in Kentucky from the critical habitat designations 
due to economic impact far outweigh the benefits of their inclusion. 
With over 2,000 river miles across 9 States, and an extensive list of 
industries and activities impacted by the proposed critical habitat 
designations, the commenter asserted that the anticipated $327,000 in 
annual costs outlined in the economic analysis does not fully capture 
the economic hardship placed on the surrounding communities.
    Our Response: These comments do not identify specific data sources 
or assumptions used in the economic analysis of critical habitat 
designation, nor did the commenter provide new information that could 
be used to revise our economic analysis. We find our economic analysis 
presents a reasonable estimate of the incremental impact (the cost 
beyond what would be incurred without the designation of critical 
habitat for longsolid and round hickorynut). Our economic analysis 
focuses on the incremental impact of the critical habitat designation 
because the statutory purposes of the economic analysis are to inform 
the mandatory consideration of the economic impact of the designation 
of critical habitat, as well as to inform the discretionary section 
4(b)(2) exclusion analysis, and to determine compliance with relevant 
statutes and Executive Orders.
    (9) Comment: Multiple commenters expressed concern about impacts of 
the proposed rule on tourism and recreation; however, many commenters 
focused on impacts associated with the proposed listing rule as 
compared to impacts associated with the proposed 4(d) rule or critical 
habitat designation. These commenters described the importance of 
tourism to the local economies, particularly in the following Kentucky 
counties: Rockcastle, Laurel (county seat is London), and Taylor. Some 
commenters stated that they oppose any action that would limit the 
current or future levels of fishing, boating, hiking, or other 
recreational activities, including impacts to the lands adjoining the 
affected rivers. One commenter stated that the proposed rule would 
negatively impact the economy of this area to the point of halting the 
growth and development of a community.
    Our Response: The Act requires the Secretary to base listing 
determinations solely on the best scientific and commercial data 
available; thus, we cannot factor possible economic costs to tourism or 
other industries into a decision to list a species. Although we 
acknowledge that listing either species could result in additional 
costs given the protections afforded to listed species, we do not 
anticipate these protections as affecting current or future levels of 
fishing, boating, hiking, or other recreational activities. Separately, 
we are required to consider economic costs for designating critical 
habitat. Our economic analysis of critical habitat designation does not 
anticipate that the designation will result in additional conservation 
efforts that would not already occur due to the listing of longsolid 
and round hickorynut or presence of other listed species in critical 
habitat areas. As such, the critical habitat designation for the 
longsolid and round hickorynut is not anticipated to result in 
additional restrictions or requirements for recreation and tourism 
activities, beyond those already anticipated to occur absent of this 
critical habitat designation.
    (10) Comment: Several commenters expressed concern that the 
proposed rule would adversely affect local farmers and livestock 
producers; many commenters were focused on impacts associated with 
listing the species. Commenters expressed concern that the proposed 
rule would cause a loss of farming revenue, which would have broad 
adverse effects on their communities. One commenter expressed concern 
that the proposed rule may halt agricultural operations.
    Our Response: It is our statutory requirement to ensure that 
listing decisions are based solely on biological considerations and not 
economic impacts; thus, costs from listing the longsolid or the round 
hickorynut cannot be factored into the listing decisions. Because the 
primary purpose of the economic analysis is to facilitate the mandatory 
consideration of the economic impact of the designation of critical 
habitat, to inform the discretionary section 4(b)(2) exclusion 
analysis, and to determine compliance with relevant statutes and 
Executive Orders, the economic analysis focused on the incremental 
impact of the critical habitat designation. The economic analysis of 
the designation of critical habitat for the longsolid and round 
hickorynut follows this incremental approach. See also our responses to 
Comments (8) and (9), above.
    We recognize in the economic analysis that critical habitat 
designation may cause landowners to perceive that private lands 
(including farming, agricultural, or livestock operations) will be 
subject to use restrictions or litigation from third parties, resulting 
in costs. However, we are unable to quantify the degree to which the 
public's perception of possible restrictions on the use of private land 
designated as critical habitat may affect private property values. 
Further, we recognize that a number of factors may already result in 
perception-related effects on these private lands, including

[[Page 14835]]

the listing of the species and the presence of other listed species and 
critical habitats in these areas, which may temper any additional 
perception-related effects of this critical habitat designation.
    (11) Comment: One commenter expressed concern that the economic 
analysis does not sufficiently address the potential benefits of the 
designation of critical habitat. Specifically, the commenter requests 
that we take into consideration the economic benefits of protecting 
habitat for these mussels, including ecosystem services, the protection 
of clean water, the reduced cost of water treatment for drinking water 
supplies, as well as public health benefits.
    Our Response: The primary intended benefit of critical habitat 
designation for the longsolid and round hickorynut is to support the 
species' long-term conservation. Generally speaking, critical habitat 
designation could also generate ancillary benefits such as improved 
drinking water quality or public health benefits. However, as described 
in section 3 of the economic analysis (Industrial Economics, Inc. 2020, 
pp. 7-9), incremental land or water management changes are unlikely to 
result from the designation of critical habitat for the longsolid and 
round hickorynut. Similarly, no additional project modifications to 
avoid adverse modification of critical habitat for the longsolid or 
round hickorynut mussels are anticipated. Therefore, in this instance, 
critical habitat designation is unlikely to incrementally affect the 
types of ancillary benefits described by the commenter.

Public Comments--Forestry

    (12) Comment: One commenter asserted that the information in the 
proposed rule and the SSA report would lead the casual reader to think 
that ``forest clearing'' is the same as ``silviculture,'' and that 
these two activities are the leading threats to the species, which is 
not the case.
    Our Response: We agree that forest clearing and silviculture are 
not synonymous and note that the latter is not a primary threat to the 
longsolid or round hickorynut. For clarity, ``forest clearing'' is the 
removal of forested habitats through tree removal to facilitate a 
different land use, thereby altering ecosystem function. Silvicultural 
practices control the growth, composition, structure, and quality of 
forests at the stand-level to meet values and needs, specifically 
timber production; however, they do not alter land use. The SSA reports 
have been revised to clarify this distinction. Please see more 
discussion and revised language regarding silviculture under Forest 
Conversion in Threats Analysis, above.
    (13) Comment: Multiple commenters asserted that forestry BMPs are 
implemented at high rates nationally and in some States where one or 
both species occur, and thus requested an exception in the 4(d) rule 
for forestry activities.
    Our Response: We recognize that silvicultural operations are widely 
implemented in accordance with State-approved best management practices 
(BMPs; as reviewed by Cristan et al. 2016, entire), and the adherence 
to these BMPs broadly protects water quality, particularly related to 
sedimentation (as reviewed by Cristan et al. 2016, entire; Warrington 
et al. 2017, entire; and Schilling et al. 2021, entire). We added that 
statement under Forest Conversion in Threats Analysis, above. In 
addition, we agree that the best available science indicates that 
proper implementation of forestry BMPs reduces negative effects on 
water quality outcomes compared to historical silvicultural practices 
or those that do not apply or properly implement BMPs. Given BMPs 
generally are implemented at high rates, we added an exception to 
incidental take in the section 4(d) rule resulting from forestry 
activities that follow state approved forest management BMPs (see II. 
Final Rule Issued Under Section 4(d) of the Act, above).
    (14) Comment: One commenter stated that forest certification 
programs provide assurance that BMPs are implemented in the ranges of 
both species and requested the addition of an exception in the 4(d) 
rule for State-certified forestry programs.
    Our Response: We acknowledge and support the continued 
implementation of the forest certification programs and their State-
approved BMPs. Given that we added an exception to incidental take in 
the section 4(d) rule resulting from forestry activities that follow 
state approved forest management BMPs and all State-certified forestry 
programs implement these BMPs at high rates, an additional exception 
specifically targeting State-certified forestry programs would be 
redundant. We also note that most longsolid and round hickorynut 
populations occurring on forest lands are within U.S. National Forests 
(e.g., Allegheny, Daniel Boone, George Washington and Jefferson, and 
Wayne National Forests), which are subject to section 7 consultation 
even with the incidental take exception resulting from forestry and 
silviculture activities.
    (15) Comment: One commenter stated that take resulting from 
silviculture activities should not be included in a 4(d) rule for the 
longsolid because of the limited scope of this species' potential nexus 
with silviculture activities; another commenter encouraged the Service 
to recognize the positive role of responsible forest management and to 
articulate this in the final rule. As such, the commenter recommended 
adding an exception to the 4(d) rule for silvicultural practices and 
forest management activities that implement State-approved BMPs.
    Our Response: To the extent silvicultural practices are implemented 
in a manner that follows State-approved BMPs, we agree with the 
commenter that there is limited potential for the longsolid to be 
exposed to silvicultural activities. We recognize responsible forest 
management that implements State-approved BMPs as a land use activity 
that can promote stable riparian vegetation and aquatic habitats. The 
4(d) rule is intended to provide exceptions for proactive conservation 
efforts, such as population and habitat restoration and protection. 
Therefore, in the 4(d) rule for longsolid and round hickorynut, we have 
added an exception for incidental take resulting from forestry 
activities that follow State-approved forest management BMPs.

Public Comments--Miscellaneous

    (16) Comment: Several commenters claimed that the proposed critical 
habitat designations are insufficient. Generally, the commenters 
contend that the current occupied habitat does not provide enough space 
for the populations to recover and that unoccupied habitat should be 
included in the critical habitat designation in anticipation of the 
species' restoration or population expansion. One commenter requested 
designation of unoccupied habitat in the Cumberland, Ohio, and 
Tennessee River basins for both species, while a different commenter 
also included the Great Lakes and Lower Mississippi River basins 
specifically for the round hickorynut.
    Our Response: 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

[[Page 14836]]

and commercial data available, those physical or biological features 
that are essential to the conservation of the species (such as space, 
food, cover, and protected habitat). In identifying those physical or 
biological features within an area, we focus on the specific features 
that support the life-history needs of the species, including but not 
limited to, water characteristics, soil type, geological features, 
prey, vegetation, symbiotic species, or other features.
    We determine whether unoccupied areas are essential for the 
conservation of the species by considering the life-history, status, 
and conservation needs of the species. This determination is further 
informed by any generalized conservation strategy, criteria, or outline 
that may have been developed for the species to provide a substantive 
foundation for identifying which features and specific areas are 
essential to the conservation of the species and, as a result, the 
development of the critical habitat designation.
    We are not proposing to designate as critical habitat any areas 
outside the geographical area currently occupied by the species because 
we determined that occupied areas are sufficient to conserve the 
longsolid and round hickorynut. For the longsolid, in total, we are 
designating approximately 1,115 river mi (1,794 river km) within 12 
units of critical habitat; and for the round hickorynut, in total, we 
are designating approximately 921 river mi (1,482 river km) within 14 
units of critical habitat. The critical habitat designation focuses on 
current strongholds and those populations with sufficient resiliency in 
determining the features that are essential for the conservation of the 
species (see Criteria Used to Identify Critical Habitat, above). These 
rivers and streams (identified as critical habitat for the longsolid 
and round hickorynut) contain populations that are large and dense 
enough, that are most likely to be self-sustaining over time (despite 
fluctuations in local conditions), and that also have retained the 
physical or biological features that will allow for the maintenance and 
expansion of existing populations. These units also represent 
populations that are stable and distributed over a wide geographic 
area. We recognize that habitat is dynamic, and species may move from 
one area to another over time. Thus, critical habitat designated at a 
particular point in time may not include all of the habitat areas that 
we may later determine are necessary for the recovery of the species. 
For these reasons, a critical habitat designation does not signal that 
habitat outside the designated area is unimportant or may not be needed 
eventually 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.

Required Determinations

Regulatory Planning and Review (Executive Orders 12866 and 13563)

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

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

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

[[Page 14837]]

be directly regulated by this rulemaking, we certify that this critical 
habitat designation will not have a significant economic impact on a 
substantial number of small entities.
    During the development of this final rule, we reviewed and 
evaluated all information submitted during the comment period on the 
September 29, 2020, proposed rule (85 FR 61384) that may pertain to our 
consideration of the probable incremental economic impacts of this 
critical habitat designation. Based on this information, we affirm our 
certification that this critical habitat designation will not have a 
significant economic impact on a substantial number of small entities, 
and a regulatory flexibility analysis is not required.

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

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

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

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

Takings--Executive Order 12630

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

Federalism--Executive Order 13132

    In accordance with E.O. 13132 (Federalism), this rule does not have 
significant Federalism effects. A federalism summary impact statement 
is not required. In keeping with Department of the Interior and 
Department of Commerce policy, we requested information from, and 
coordinated development of these critical habitat designations with, 
appropriate State resource agencies. From a federalism perspective, the 
designation of critical habitat directly affects only the 
responsibilities of Federal agencies. The Act imposes no other duties 
with respect to critical habitat, either for States and local 
governments, or for anyone else. As a result, this final rule does not 
have substantial direct effects either on the States, or on the 
relationship between the national government and the States, or on the 
distribution of powers and responsibilities among the various levels of 
government. The designations may have some benefit to these governments 
because the areas that contain the features essential to the 
conservation of the species are more clearly defined, and the physical 
or

[[Page 14838]]

biological features of the habitat necessary for the conservation of 
the species are specifically identified. This information does not 
alter where and what federally sponsored activities may occur. However, 
it may assist State and local governments in long-range planning 
because they no longer have to wait for case-by-case section 7 
consultations to occur.
    Where State and local governments require approval or authorization 
from a Federal agency for actions that may affect critical habitat, 
consultation under section 7(a)(2) of the Act will be required. While 
non-Federal entities that receive Federal funding, assistance, or 
permits, or that otherwise require approval or authorization from a 
Federal agency for an action, may be indirectly impacted by the 
designation of critical habitat, the legally binding duty to avoid 
destruction or adverse modification of critical habitat rests squarely 
on the Federal agency.

Civil Justice Reform--Executive Order 12988

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

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

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

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

    Regulations adopted pursuant to section 4(a) of the Act are exempt 
from the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et 
seq.) and do not require an environmental analyses under NEPA. We 
published a notice outlining our reasons for this determination in the 
Federal Register on October 25, 1983 (48 FR 49244). This includes 
listing, delisting, and reclassification rules, as well as critical 
habitat designations and species-specific protective regulations 
promulgated concurrently with a decision to list or reclassify a 
species as threatened. The courts have upheld this position (e.g., 
Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 1995) (critical 
habitat); Center for Biological Diversity v. U.S. Fish and Wildlife 
Service., 2005 WL 2000928 (N.D. Cal. Aug. 19, 2005) (concurrent 4(d) 
rule)).

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), Executive Order 13175 (Consultation and 
Coordination with Indian Tribal Governments), and the Department of the 
Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized federally 
recognized Tribes on a government-to-government basis. In accordance 
with Secretarial Order 3206 of June 5, 1997 (American Indian Tribal 
Rights, Federal-Tribal Trust Responsibilities, and the Endangered 
Species Act), we readily acknowledge our responsibilities to work 
directly with Tribes in developing programs for healthy ecosystems, to 
acknowledge that Tribal lands are not subject to the same controls as 
Federal public lands, to remain sensitive to Indian culture, and to 
make information available to Tribes. We have determined that no Tribal 
lands fall within the boundaries of the final critical habitat for the 
longsolid and round hickorynut, so no Tribal lands would be affected by 
the designations.

References Cited

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

Authors

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

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

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

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

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

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


0
2. Amend Sec.  17.11(h) by adding entries for ``Hickorynut, round'' and 
``Longsolid'' to the List of Endangered and Threatened Wildlife in 
alphabetical order under CLAMS to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                          Listing citations and
           Common name              Scientific name        Where listed        Status        applicable rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
                                                      Clams
 
                                                  * * * * * * *
Hickorynut, round...............  Obovaria subrotunda  Wherever found.....  T            88 FR [Insert Federal
                                                                                          Register page where
                                                                                          the document begins],
                                                                                          March 9, 2023; 50 CFR
                                                                                          17.45(d); \4d\ 50 CFR
                                                                                          17.95(f).\CH\
 

[[Page 14839]]

 
                                                  * * * * * * *
Longsolid.......................  Fusconaia            Wherever found.....  T            88 FR [Insert Federal
                                   subrotunda.                                            Register page where
                                                                                          the document begins],
                                                                                          March 9, 2023; 50 CFR
                                                                                          17.45(d); \4d\ 50 CFR
                                                                                          17.95(f).\CH\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------


0
3. Amend Sec.  17.45 by adding paragraphs (c) and (d) to read as set 
forth below:


Sec.  17.45  Special rules--snails and clams.

* * * * *
    (c) [Reserved]
    (d) Longsolid (Fusconaia subrotunda) and round hickorynut (Obovaria 
subrotunda).
    (1) Prohibitions. The following prohibitions that apply to 
endangered wildlife also apply to the longsolid and round hickorynut. 
Except as provided under paragraph (d)(2) of this section and 
Sec. Sec.  17.4 and 17.5, it is unlawful for any person subject to the 
jurisdiction of the United States to commit, to attempt to commit, to 
solicit another to commit, or cause to be committed, any of the 
following acts in regard to these species:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken specimens, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of commercial 
activity, as set forth at Sec.  17.21(e) for endangered wildlife.
    (v) Sale or offer for sale, as set forth at Sec.  17.21(f) for 
endangered wildlife.
    (2) Exceptions from prohibitions. In regard to these species, you 
may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take, as set forth at Sec.  17.31(b).
    (iv) Take incidental to an otherwise lawful activity caused by:
    (A) Conservation and restoration efforts for listed species 
conducted by State wildlife agencies, including, but not limited to, 
population monitoring, relocation, and collection of broodstock; tissue 
collection for genetic analysis; captive propagation; and subsequent 
stocking into currently occupied and unoccupied areas within the 
historical range of the species.
    (B) Channel and bank restoration projects that create natural, 
physically stable, ecologically functioning streams (or stream and 
wetland systems) that are reconnected with their groundwater aquifers. 
These projects can be accomplished using a variety of methods, but the 
desired outcome is a natural channel with low shear stress (force of 
water moving against the channel); bank heights that enable 
reconnection to the floodplain; a reconnection of surface and 
groundwater systems, resulting in perennial flows in the channel; 
riffles and pools composed of existing soil, rock, and wood instead of 
large imported materials; low compaction of soils within adjacent 
riparian areas; and inclusion of riparian wetlands.
    (C) Bank stabilization projects that use bioengineering methods to 
replace pre-existing, bare, eroding stream banks with vegetated, stable 
stream banks, thereby reducing bank erosion and instream sedimentation 
and improving habitat conditions for the species. Following these 
bioengineering methods, stream banks may be stabilized using native 
species live stakes (live, vegetative cuttings inserted or tamped into 
the ground in a manner that allows the stake to take root and grow), 
native species live fascines (live branch cuttings, usually willows, 
bound together into long, cigar-shaped bundles), or native species 
brush layering (cuttings or branches of easily rooted tree species 
layered between successive lifts of soil fill). Native species 
vegetation includes woody and herbaceous species appropriate for the 
region and habitat conditions. These methods will not include the sole 
use of quarried rock (rip-rap) or the use of rock baskets or gabion 
structures. Prior to channel restoration and bank stabilization 
actions, surveys conducted in coordination with the appropriate Service 
field office to determine presence of longsolid and round hickorynut 
must be performed, and if located, relocation prior to project 
implementation may be necessary, with post-implementation monitoring. 
To qualify under this exemption, channel restoration and bank 
stabilization actions must satisfy all Federal, State, and local 
permitting requirements.
    (D) Forest management activities that implement State-approved best 
management practices.
    (v) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.

0
4. Amend Sec.  17.95(f) by adding, immediately following the entry for 
``Carolina Heelsplitter (Lasmigona decorata),'' entries for ``Round 
Hickorynut (Obovaria subrotunda)'' and ``Longsolid (Fusconaia 
subrotunda)'' to read as follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and Snails.
* * * * *
Round Hickorynut (Obovaria subrotunda)
    (1) Critical habitat units for the round hickorynut are depicted on 
the maps in this entry for Jackson, Madison, and Marshall Counties, 
Alabama; Fulton, Marshall, Pulaski, and Starke Counties, Indiana; Bath, 
Butler, Campbell, Edmonson, Fleming, Green, Harrison, Hart, Kenton, 
Laurel, Morgan, Nicholas, Pendleton, Pulaski, Rockcastle, Robertson, 
Rowan, and Warren Counties, Kentucky; Montgomery County, Mississippi; 
Bedford, Marshall, and Maury Counties, Tennessee; Ashtabula, Lake, and 
Trumbull Counties, Ohio; Crawford and Mercer Counties, Pennsylvania; 
and Braxton, Calhoun, Clay, Doddridge, Fayette, Gilmer, Kanawha, 
Pleasants, Ritchie, Tyler, and Wood Counties, West Virginia.
    (2) Within these areas, the physical or biological features 
essential to the conservation of the round hickorynut consist of the 
following components:
    (i) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species is found and to maintain stream connectivity, specifically 
providing for the exchange of nutrients and sediment for maintenance of 
the mussel's and fish host's habitat and food availability, maintenance 
of spawning habitat for native fishes, and the ability for newly 
transformed juveniles to settle and become established in their 
habitats. Adequate flows ensure delivery of oxygen, enable 
reproduction, deliver food to filter-feeding mussels, and

[[Page 14840]]

reduce contaminants and fine sediments from interstitial spaces. Stream 
velocity is not static over time, and variations may be attributed to 
seasonal changes (with higher flows in winter/spring and lower flows in 
summer/fall), extreme weather events (e.g., drought or floods), or 
anthropogenic influence (e.g., flow regulation via impoundments).
    (ii) Suitable substrates and connected instream habitats, 
characterized by geomorphically 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) with habitats that support a diversity of freshwater mussel 
and native fish (such as, stable riffle-run-pool habitats that provide 
flow refuges consisting of predominantly silt-free, stable sand, 
gravel, and cobble substrates).
    (iii) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including (but not limited to): Dissolved oxygen 
(generally above 2 to 3 parts per million (ppm)), salinity (generally 
below 2 to 4 ppm), and temperature (generally below 86 [deg]F ([deg]F) 
(30 [deg]Celsius ([deg]C)). Additionally, water and sediment should be 
low in ammonia (generally below 0.5 ppm total ammonia-nitrogen) and 
heavy metal concentrations, and lack excessive total suspended solids 
and other pollutants.
    (iv) The presence and abundance of fish hosts necessary for 
recruitment of the round hickorynut (i.e., eastern sand darter 
(Ammocrypta pellucida), emerald darter (Etheostoma baileyi), greenside 
darter (E. blennioides), Iowa darter (E. exile), fantail darter (E. 
flabellare), Cumberland darter (E. susanae), spangled darter (E. 
obama), variegate darter (E. variatum), blackside darter (Percina 
maculata), frecklebelly darter (P. stictogaster), and banded sculpin 
(Cottus carolinae)).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
April 10, 2023.
    (4) Data layers defining map units were created by overlaying 
Natural Heritage Element Occurrence data and U.S. Geological Survey 
hydrologic data for stream reaches. The hydrologic data used in the 
critical habitat maps were extracted from the U.S. Geological Survey 
1:1M scale nationwide hydrologic layer (https://www.usgs.gov/core-science-systems/ngp/national-hydrography) with a projection of 
EPSG:4269--NAD83 Geographic. Natural Heritage program and State mussel 
database species presence data from Pennsylvania, Ohio, Indiana, West 
Virginia, Kentucky, Tennessee, Alabama, and Mississippi were used to 
select specific river and stream segments for inclusion in the critical 
habitat layer. The maps in this entry, as modified by any accompanying 
regulatory text, establish the boundaries of the critical habitat 
designation. The coordinates or plot points or both on which each map 
is based are available to the public at the Service's internet site at 
https://www.regulations.gov at Docket No. FWS-R4-ES-2020-0010, and at 
the field office responsible for this designation. You may obtain field 
office location information by contacting one of the Service regional 
offices, the addresses of which are listed at 50 CFR 2.2.
    (5) Index map for the round hickorynut follows:

Figure 1 to Round Hickorynut (Obovaria subrotunda) paragraph (5)
BILLING CODE 4333-15-P

[[Page 14841]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.017

    (6) Unit RH 1: Shenango River; Crawford and Mercer Counties, 
Pennsylvania.
    (i) Unit RH 1 consists of 22 river miles (mi) (35.5 kilometers 
(km)) of the Shenango River in Crawford County, Pennsylvania, from 
Pymatuning Dam downstream to the point of inundation by Shenango River 
Lake near Big Bend, Mercer County, Pennsylvania. Approximately 15 river 
mi (24.3 km; 68 percent) of riparian lands that border the unit are 
private ownership, and 7 river mi (11.1 km; 32 percent) are public 
(Federal or State) ownership. This unit is immediately downstream from 
Pymatuning Dam, which is owned by the State of Pennsylvania.
    (ii) Map of Unit RH 1 follows:

Figure 2 to Round Hickorynut (Obovaria subrotunda) paragraph (6)(ii)

[[Page 14842]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.018

    (7) Unit RH 2: Grand River; Ashtabula, Lake, and Trumbull Counties, 
Ohio.
    (i) Unit RH 2 consists of 92 river mi (148.2 km) of the Grand River 
in Ashtabula, Lake, and Trumbull Counties, Ohio. Approximately 59 river 
mi (95.2 km; 64 percent) of riparian lands that border the unit are 
private ownership, and 33 river mi (53 km; 36 percent) are public 
(State or local) ownership. The Grand River is a State Wild and Scenic 
River. The Wild River designation includes approximately 23 river mi 
(37 km) from the Harpersfield Covered Bridge downstream to the Norfolk 
and Western Railroad Trestle in Lake County, and approximately 33 mi 
(53 km) from the U.S. Route 322 Bridge in Ashtabula County downstream 
to the Harpersfield Covered Bridge. Harpersfield Dam within this unit 
is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit RH 2 follows:

Figure 3 to Round Hickorynut (Obovaria subrotunda) paragraph (7)(ii)

[[Page 14843]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.019

    (8) Unit RH 3: Tippecanoe River; Fulton, Marshall, Pulaski, and 
Starke Counties, Indiana.
    (i) Unit RH 3 consists of 75 river mi (120.8 km) of the Tippecanoe 
River in Fulton, Marshall, Pulaski, and Starke Counties, Indiana. 
Approximately 66 river mi (105.6 km; 89 percent) of riparian lands that 
border the unit are private ownership, and 9 river mi (14.5 km; 11 
percent) are public (State or easement) ownership.
    (ii) Map of Unit RH 3 follows:

Figure 4 to Round Hickorynut (Obovaria subrotunda) paragraph (8)(ii)

[[Page 14844]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.020

    (9) Unit RH 4: Middle Island Creek; Doddridge, Pleasants, and Tyler 
Counties, West Virginia.
    (i) Unit RH 4 consists of 75 stream mi (120.8 km) of Middle Island 
Creek in Doddridge, Pleasants, and Tyler Counties, West Virginia. 
Approximately 74.8 stream mi (120.4 km; 99 percent) of riparian lands 
that border the unit are private ownership, and 0.2 stream mi (0.4 km; 
less than 1 percent) is public ownership.
    (ii) Map of Unit RH 4 follows:

Figure 5 to Round Hickorynut (Obovaria subrotunda) paragraph (9)(ii)

[[Page 14845]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.021

    (10) Unit RH 5: Little Kanawha River; Calhoun, Gilmer, Ritchie, and 
Wood Counties, West Virginia.
    (i) Unit RH 5 consists of 110 stream mi (176.6 km) of the Little 
Kanawha River in Calhoun, Gilmer, Ritchie, and Wood Counties, West 
Virginia. Approximately 109 river mi (175.4 km; 99 percent) of riparian 
lands that border the unit are private ownership, and 0.7 river mi (1.2 
km; 1 percent) are public (Federal, State, or local) ownership. This 
unit is directly below Burnsville Dam, which is operated by the U.S. 
Army Corps of Engineers.
    (ii) Map of Unit RH 5 follows:

Figure 6 to Round Hickorynut (Obovaria subrotunda) paragraph (10)(ii)

[[Page 14846]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.022

    (11) Unit RH 6: Elk River; Braxton, Clay, and Kanawha Counties, 
West Virginia.
    (i) Unit RH 6 consists of 101 river mi (163 km) of the Elk River in 
Braxton, Clay, and Kanawha Counties, West Virginia. Approximately 93 
river mi (150.3 km; 92 percent) of riparian lands that border the unit 
are private ownership, and 7 river mi (12.7 km; 8 percent) are public 
(Federal, State, or local) ownership. This unit is immediately below 
Sutton Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit RH 6 follows:

Figure 7 to Round Hickorynut (Obovaria subrotunda) paragraph (11)(ii)

[[Page 14847]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.023

    (12) Unit RH 7: Kanawha River; Fayette and Kanawha Counties, West 
Virginia.
    (i) Unit RH 7 consists of 37.5 river mi (60.4 km) of the Kanawha 
River in Fayette and Kanawha Counties, West Virginia. Approximately 33 
river mi (53.2 km; 90 percent) of riparian lands that border the unit 
are private ownership, and 4 river mi (7.2 km; 10 percent) are public 
(Federal, State, or local) ownership. London and Marmet locks and dams 
within this unit are operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit RH 7 follows:

Figure 8 to Round Hickorynut (Obovaria subrotunda) paragraph (12)(ii)

[[Page 14848]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.024

    (13) Unit RH 8: Licking River; Bath, Campbell, Fleming, Harrison, 
Kenton, Morgan, Nicholas, Pendleton, Robertson, and Rowan Counties, 
Kentucky.
    (i) Unit RH 8 consists of 150 river mi (241.9 km) of the Licking 
River in Bath, Campbell, Fleming, Harrison, Kenton, Morgan, Nicholas, 
Pendleton, Robertson, and Rowan Counties, Kentucky. Approximately 131 
river mi (211.8 km; 87 percent) of riparian lands that border the unit 
are private ownership, and 18 river mi (30 km; 13 percent) are public 
(Federal, State, or local) ownership. This unit is directly below Cave 
Run Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit RH 8 follows:

Figure 9 to Round Hickorynut (Obovaria subrotunda) paragraph (13)(ii)

[[Page 14849]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.025

    (14) Unit RH 9: Rockcastle River; Laurel, Pulaski, and Rockcastle 
Counties, Kentucky.
    (i) Unit RH 9 consists of 15.3 river mi (24.6 km) of the Rockcastle 
River in Laurel, Pulaski, and Rockcastle Counties, Kentucky. 
Approximately 0.3 river mi (0.4 km; 1 percent) of riparian lands that 
border the unit is private ownership, and 15 river mi (24.2 km; 99 
percent) are public (Federal; Daniel Boone National Forest) ownership.
    (ii) Map of Unit RH 9 follows:

Figure 10 to Round Hickorynut (Obovaria subrotunda) paragraph (14)(ii)

[[Page 14850]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.026

    (15) Unit RH 10: Buck Creek; Pulaski County, Kentucky.
    (i) Unit RH 10 consists of 36 stream mi (58.1 km) of Buck Creek in 
Pulaski County, Kentucky. Approximately 33 stream mi (52.6 km; 92 
percent) of riparian lands that border the unit are private ownership, 
and 3 stream mi (5.5 km; 8 percent) are public (State or local) 
ownership.
    (ii) Map of Unit RH 10 follows:

Figure 11 to Round Hickorynut (Obovaria subrotunda) paragraph (15)(ii)

[[Page 14851]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.027

    (16) Unit RH 11: Green River; Hart, Edmonson, Green, Butler, and 
Warren Counties, Kentucky.
    (i) Unit RH 11 consists of 98 river mi (157.7 km) of the Green 
River in Butler, Edmonson, Green, Hart, and Warren Counties, Kentucky. 
Approximately 61 river mi (98.4 km; 62 percent) of riparian lands that 
border the unit are private ownership, and 37 river mi (59.4 km; 38 
percent) are public (Federal or State) ownership, including portions of 
Mammoth Cave National Park. This unit is located directly below Green 
River Lake Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit RH 11 follows:

Figure 12 to Round Hickorynut (Obovaria subrotunda) paragraph (16)(ii)

[[Page 14852]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.028

    (17) Unit RH 12: Paint Rock River; Jackson, Madison, and Marshall 
Counties, Alabama.
    (i) Unit RH 12 consists of 48 river mi (77.5 km) of the Paint Rock 
River in Jackson, Madison, and Marshall Counties, Alabama. 
Approximately 2 river mi (4.1 km; 2 percent) of riparian lands that 
border the unit are private ownership, and 46 river mi (73.4 km; 98 
percent) are public (Federal or State) ownership.
    (ii) Map of Unit RH 12 follows:

Figure 13 to Round Hickorynut (Obovaria subrotunda) paragraph (17)(ii)

[[Page 14853]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.029

    (18) Unit RH 13: Duck River; Bedford, Marshall, and Maury Counties, 
Tennessee.
    (i) Unit RH 13 consists of 59 river mi (94.8 km) of the Duck River 
in Bedford, Marshall, and Maury Counties, Tennessee. Approximately 27 
river mi (43.7 km; 47 percent) of riparian lands that border the unit 
are private ownership, and 32 river mi (51.1 km; 53 percent) are public 
(State or local) ownership.
    (ii) Map of Unit RH 13 follows:

Figure 14 to Round Hickorynut (Obovaria subrotunda) paragraph (18)(ii)

[[Page 14854]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.030

    (19) Unit RH 14: Big Black River; Montgomery County, Mississippi.
    (i) Unit RH 14 consists of 4 river mi (7 km) of the Big Black River 
in Montgomery County, Mississippi. All of riparian lands that border 
the unit are private ownership.
    (ii) Map of Unit RH 14 follows:

Figure 15 to Round Hickorynut (Obovaria subrotunda) paragraph (19)(ii)

[[Page 14855]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.031

Longsolid (Fusconaia subrotunda)
    (1) Critical habitat units for the longsolid are depicted on the 
maps in this entry for Jackson, Madison, and Marshall Counties, 
Alabama; Bath, Butler, Campbell, Edmonson, Fleming, Green, Harrison, 
Hart, Kenton, Morgan, Nicholas, Pendleton, Robertson, Rowan, Taylor, 
and Warren Counties, Kentucky; Clarion, Crawford, Erie, Forest, Mercer, 
Venango, and Warren Counties, Pennsylvania; Claiborne, Hancock, 
Hawkins, Smith, Trousdale, and Wilson Counties, Tennessee; Russell, 
Scott, Tazewell, and Wise Counties, Virginia; and Braxton, Calhoun, 
Clay, Doddridge, Fayette, Gilmer, Kanawha, Ritchie, Tyler, and Wood 
Counties, West Virginia.
    (2) Within these areas, the physical or biological features 
essential to the conservation of the longsolid consist of the following 
components:
    (i) Adequate flows, or a hydrologic flow regime (magnitude, timing, 
frequency, duration, rate of change, and overall seasonality of 
discharge over time), necessary to maintain benthic habitats where the 
species is found and

[[Page 14856]]

to maintain stream connectivity, specifically providing for the 
exchange of nutrients and sediment for maintenance of the mussel's and 
fish host's habitat and food availability, maintenance of spawning 
habitat for native fishes, and the ability for newly transformed 
juveniles to settle and become established in their habitats. Adequate 
flows ensure delivery of oxygen, enable reproduction, deliver food to 
filter-feeding mussels, and reduce contaminants and fine sediments from 
interstitial spaces. Stream velocity is not static over time, and 
variations may be attributed to seasonal changes (with higher flows in 
winter/spring and lower flows in summer/fall), extreme weather events 
(e.g., drought or floods), or anthropogenic influence (e.g., flow 
regulation via impoundments).
    (ii) Suitable substrates and connected instream habitats, 
characterized by geomorphically 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) with habitats that support a diversity of freshwater mussel 
and native fish (such as, stable riffle-run-pool habitats that provide 
flow refuges consisting of predominantly silt-free, stable sand, 
gravel, and cobble substrates).
    (iii) Water and sediment quality necessary to sustain natural 
physiological processes for normal behavior, growth, and viability of 
all life stages, including (but not limited to): Dissolved oxygen 
(generally above 2 to 3 parts per million (ppm)), salinity (generally 
below 2 to 4 ppm), and temperature (generally below 86 [deg]Fahrenheit 
([deg]F) (30 [deg]Celsius ([deg]C)). Additionally, water and sediment 
should be low in ammonia (generally below 0.5 ppm total ammonia-
nitrogen) and heavy metal concentrations, and lack excessive total 
suspended solids and other pollutants.
    (iv) The presence and abundance of fish hosts necessary for 
recruitment of the longsolid (currently unknown, likely includes the 
minnows of the family Cyprinidae and banded sculpin (Cottus 
carolinae)).
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
April 10, 2023.
    (4) Data layers defining map units were created by overlaying 
Natural Heritage Element Occurrence data and U.S. Geological Survey 
hydrologic data for stream reaches. The hydrologic data used in the 
critical habitat maps were extracted from the U.S. Geological Survey 
1:1M scale nationwide hydrologic layer (https://www.usgs.gov/core-science-systems/ngp/national-hydrography) with a projection of 
EPSG:4269--NAD83 Geographic. Natural Heritage program and State mussel 
database species presence data from Pennsylvania, West Virginia, 
Virginia, Kentucky, Tennessee, and Alabama were used to select specific 
river and stream segments for inclusion in the critical habitat layer. 
The maps in this entry, as modified by any accompanying regulatory 
text, establish the boundaries of the critical habitat designation. The 
coordinates or plot points or both on which each map is based are 
available to the public at the Service's internet site at https://www.regulations.gov at Docket No. FWS-R4-ES-2020-0010, and at the field 
office responsible for this designation. You may obtain field office 
location information by contacting one of the Service regional offices, 
the addresses of which are listed at 50 CFR 2.2.
    (5) Index map for the longsolid follows:

Figure 1 to Longsolid (Fusconaia subrotunda) paragraph (5)

[[Page 14857]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.032

    (6) Unit LS 1: French Creek; Crawford, Erie, Mercer, and Venango 
Counties, Pennsylvania.
    (i) Unit LS 1 consists of 120 stream mi (191.5 km) of French Creek 
in Crawford, Erie, Mercer, and Venango Counties, Pennsylvania. 
Approximately 106 stream mi (170.6 km; 76 percent) of riparian lands 
that border the unit are private ownership, and 14 stream mi (22.1 km; 
24 percent) are public (Federal or State) ownership. This unit begins 
immediately downstream of the Union City Dam, which is operated by the 
U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 1 follows:

Figure 2 to Longsolid (Fusconaia subrotunda) paragraph (6)(ii)

[[Page 14858]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.033

    (7) Unit LS 2: Allegheny River; Clarion, Crawford, Forest, Venango, 
and Warren Counties, Pennsylvania.
    (i) Unit LS 2 consists of 99 river mi (159.3 km) of the Allegheny 
River in Clarion, Crawford, Forest, Venango, and Warren Counties, 
Pennsylvania. Approximately 15 river mi (24.1 km; 14 percent) of 
riparian lands that border the unit are private ownership, and 84 river 
mi (135.8 km; 86 percent) are public (Federal or State; primarily 
Allegheny National Forest) ownership. This unit is immediately 
downstream of Kinzua Dam, which is operated by the U.S. Army Corps of 
Engineers.
    (ii) Map of Unit LS 2 follows:

Figure 3 to Longsolid (Fusconaia subrotunda) paragraph (7)(ii)

[[Page 14859]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.034

    (8) Unit LS 3: Shenango River; Crawford and Mercer Counties, 
Pennsylvania.
    (i) Unit LS 3 consists of 22 river miles (mi) (35.5 kilometers 
(km)) of the Shenango River in Crawford County, Pennsylvania, from 
Pymatuning Dam downstream to the point of inundation by Shenango River 
Lake near Big Bend, Mercer County, Pennsylvania. Approximately 15 river 
mi (24.3 km; 68 percent) of riparian lands that border the unit are 
private ownership, and 7 river mi (11.3 km; 32 percent) are public 
(Federal or State) ownership. This unit is immediately downstream from 
the Pymatuning Dam, which is owned by the State of Pennsylvania.
    (ii) Map of Unit LS 3 follows:

Figure 4 to Longsolid (Fusconaia subrotunda) paragraph (8)(ii)

[[Page 14860]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.035

    (9) Unit LS 4: Middle Island Creek; Doddridge and Tyler Counties, 
West Virginia.
    (i) Unit LS 4 consists of 14 stream mi (23.7 km) of Middle Island 
Creek in Doddridge and Tyler Counties, West Virginia. Approximately 14 
stream mi (23.5 km; 99 percent) of riparian lands that border the unit 
are private ownership, and 0.1 stream mi (0.2 km; less than 1 percent) 
are public (local) ownership.
    (ii) Map of Unit LS 4 follows:

Figure 5 to Longsolid (Fusconaia subrotunda) paragraph (9)(ii)

[[Page 14861]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.036

    (10) Unit LS 5: Little Kanawha River; Calhoun, Gilmer, Ritchie, and 
Wood Counties, West Virginia.
    (i) Unit LS 5 consists of 123 river mi (198 km) of the Little 
Kanawha River in Calhoun, Gilmer, Ritchie, and Wood Counties, West 
Virginia. Approximately 122 river mi (197.2 km; 99 percent) are private 
ownership, and 0.53 river mi (0.9 km; 1 percent) are public (Federal or 
State) ownership. This unit is directly below the Burnsville Dam, which 
is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 5 follows:

Figure 6 to Longsolid (Fusconaia subrotunda) paragraph (10)(ii)

[[Page 14862]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.037

    (11) Unit LS 6: Elk River; Braxton, Clay, and Kanawha Counties, 
West Virginia.
    (i) Unit LS 6 consists of 101 river mi (163 km) of the Elk River in 
Braxton, Clay, and Kanawha Counties, West Virginia. Approximately 93 
river mi (150.3 km; 92 percent) of riparian lands that border the unit 
are private ownership, and 7 river mi (12.7 km; 8 percent) are public 
(Federal, State, or local) ownership. This unit is directly below 
Sutton Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 6 follows:

Figure 7 to Longsolid (Fusconaia subrotunda) paragraph (11)(ii)

[[Page 14863]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.038

    (12) Unit LS 7: Kanawha River; Fayette and Kanawha Counties, West 
Virginia.
    (i) Unit LS 7 consists of 21 river mi (33.9 km) of the Kanawha 
River in Fayette and Kanawha Counties, West Virginia. Approximately 18 
river mi (29.3 km; 90 percent) of riparian lands that border the unit 
are private ownership, and 2 river mi (4.6 km; 10 percent) are public 
(Federal, State, or local) ownership. London and Marmet locks and dams 
within this unit are operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 7 follows:

Figure 8 to Longsolid (Fusconaia subrotunda) paragraph (12)(ii)

[[Page 14864]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.039

    (13) Unit LS 8: Licking River; Bath, Campbell, Fleming, Harrison, 
Kenton, Morgan, Nicholas, Pendleton, Robertson, and Rowan Counties, 
Kentucky.
    (i) Unit LS 8 consists of 181 river mi (291.5 km) of the Licking 
River in Bath, Campbell, Fleming, Harrison, Kenton, Morgan, Nicholas, 
Pendleton, Robertson, and Rowan Counties, Kentucky. Approximately 161 
river mi (259.7 km; 90 percent) of riparian lands that border the unit 
are private ownership, and 19 river mi (31.7 km; 10 percent) are public 
(Federal, State, or local) ownership. This unit is directly below Cave 
Run Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 8 follows:

Figure 9 to Longsolid (Fusconaia subrotunda) paragraph (13)(ii)

[[Page 14865]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.040

    (14) Unit LS 9: Green River; Butler, Edmonson, Green, Hart, Taylor, 
and Warren Counties, Kentucky.
    (i) Unit LS 9 consists of 156 river mi (251.6 km) of the Green 
River in Butler, Edmonson, Green, Hart, Taylor, and Warren Counties, 
Kentucky. Approximately 105 river mi (169.2 km; 67 percent) of riparian 
lands that border the unit are private ownership, and 51 river mi (82.4 
km; 33 percent) are public (Federal, State, or local) ownership, 
including Mammoth Cave National Park. This unit is directly below Green 
River Dam, which is operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 9 follows:

Figure 10 to Longsolid (Fusconaia subrotunda) paragraph (14)(ii)

[[Page 14866]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.041

    (15) Unit LS 10: Cumberland River; Smith, Trousdale, and Wilson 
Counties, Tennessee.
    (i) Unit LS 10 consists of 48 river mi (77.5 km) of the Cumberland 
River in Smith, Trousdale, and Wilson Counties, Tennessee. All riparian 
lands that border the river are owned by the U.S. Army Corps of 
Engineers (Federal; 48 river mi (77.5 km)). This unit also falls within 
the Tennessee Wildlife Resources Agency's Rome Landing Sanctuary. 
Cordell Hull and Old Hickory Dams, upstream and downstream of this 
unit, respectively, are operated by the U.S. Army Corps of Engineers.
    (ii) Map of Unit LS 10 follows:

Figure 11 to Longsolid (Fusconaia subrotunda) paragraph (15)(ii)

[[Page 14867]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.042

    (16) Unit LS 11: Clinch River; Russell, Scott, Tazewell, and Wise 
Counties, Virginia; Claiborne, Hancock, and Hawkins Counties, 
Tennessee.
    (i) Unit LS 11 consists of 177 river mi (286.1 km) of the Clinch 
River in Russell, Scott, Tazewell, and Wise Counties, Virginia, and 
Claiborne, Hancock, and Hawkins Counties, Tennessee. Approximately 160 
river mi (258.8 km; 90 percent) of riparian lands that border the unit 
are private ownership, and 17 river mi (27.3 km; 10 percent) are public 
(Federal or State) ownership. The Tennessee portion of this unit is 
encompassed by the Tennessee Wildlife Resources Agency's Clinch River 
Sanctuary.
    (ii) Map of Unit LS 11 follows:

Figure 12 to Longsolid (Fusconaia subrotunda) paragraph (16)(ii)

[[Page 14868]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.043

    (17) Unit LS 12: Paint Rock River; Jackson, Madison, and Marshall 
Counties, Alabama.
    (i) Unit LS 12 consists of 58 river mi (94.5 km) of the Paint Rock 
River in Jackson, Madison, and Marshall Counties, Alabama. 
Approximately 2 river mi (4.1 km; 3 percent) of riparian lands that 
border the unit are private ownership, and 56 river mi (90.4 km; 97 
percent) are public (Federal or State) ownership.
    (ii) Map of Unit LS 12 follows:

Figure 13 to Longsolid (Fusconaia subrotunda) paragraph (17)(ii)

[[Page 14869]]

[GRAPHIC] [TIFF OMITTED] TR09MR23.044

* * * * *

Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-03998 Filed 3-8-23; 8:45 am]
BILLING CODE 4333-15-C