[Federal Register Volume 88, Number 161 (Tuesday, August 22, 2023)]
[Proposed Rules]
[Pages 57060-57077]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-17844]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2023-0112; FF09E21000 FXES1111090FEDR 234]
RIN 1018-BE94
Endangered and Threatened Wildlife and Plants; Endangered Species
Status for Tennessee Clubshell, Tennessee Pigtoe, and Cumberland
Moccasinshell
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to
list three Tennessee and Cumberland River basin mussel species, the
Tennessee clubshell (Pleurobema oviforme), Tennessee pigtoe (Pleuronaia
barnesiana), and Cumberland moccasinshell (Medionidus conradicus), as
endangered species under the Endangered Species Act of 1973, as amended
(Act). This determination also serves as our 12-month finding on a
petition to list the three species. After a review of the best
available scientific and commercial information, we find that listing
the Tennessee clubshell, Tennessee pigtoe, and Cumberland moccasinshell
as endangered species is warranted. If we finalize this rule as
proposed, it would extend the Act's protections to these species.
DATES: We will accept comments received or postmarked on or before
October 23, 2023. Comments submitted electronically using the Federal
eRulemaking Portal (see ADDRESSES, below) must be received by 11:59
p.m. eastern time on the closing date. We must receive requests for a
public hearing, in writing, at the address shown in FOR FURTHER
INFORMATION CONTACT by October 6, 2023.
ADDRESSES: Written comments: You may submit comments by one of the
following methods:
(1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R4-ES-2023-0112,
which is the docket number for this rulemaking. Then, click on the
Search button. On the resulting page, in the panel on the left side of
the screen, under the Document Type heading, check the Proposed Rule
box to locate this document. You may submit a comment by clicking on
``Comment.''
(2) By hard copy: Submit by U.S. mail to: Public Comments
Processing, Attn: FWS-R4-ES-2023-0112, U.S. Fish and Wildlife Service,
MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
We request that you send comments only by the methods described
above. We will post all comments on https://www.regulations.gov. This
generally means that we will post any personal information you provide
us (see Information Requested, below, for more information).
Availability of supporting materials: Supporting materials, such as
the species status assessment report, are available at https://www.regulations.gov at Docket No. FWS-R4-ES-2023-0112.
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 (16 U.S.C. 1531 et
seq.), 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 Tennessee clubshell,
Tennessee pigtoe, and Cumberland moccasinshell meet the Act's
definition of an endangered species; therefore, we are proposing to
list them as such. Listing a species as an endangered or threatened
species can be completed only by issuing a rule through the
Administrative Procedure Act rulemaking process (5 U.S.C. 551 et seq.).
What this document does. This document proposes to list the
Tennessee clubshell (Pleurobema oviforme), Tennessee pigtoe (Pleuronaia
barnesiana), and Cumberland moccasinshell (Medionidus conradicus) as
endangered species.
The basis for our action. Under the Act, we may determine that a
species is an endangered or threatened species because of any of five
factors: (A) The present or threatened destruction, modification, or
curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; or (E) other natural or manmade factors affecting its
continued existence. We have determined that the primary threats to all
three species are large impoundments, urban development, energy
development, and agriculture, which have altered natural flow regimes
and/or diminished water and substrate quality (Factor A).
Information Requested
We intend that any final action resulting from this proposed rule
will be based on the best scientific and commercial data available and
be as accurate and as effective as possible. Therefore, we request
comments or information from other governmental agencies, Native
American Tribes, the
[[Page 57061]]
scientific community, industry, or any other interested parties
concerning this proposed rule.
We particularly seek comments concerning:
(1) The species' biology, ranges, and population trends, including:
(a) Biological or ecological requirements of the species, including
habitat requirements for feeding, breeding, and sheltering;
(b) Genetics and taxonomy;
(c) Historical and current ranges, including distribution patterns
and the locations of any additional populations of these species;
(d) Historical and current population levels, and current and
projected trends; and
(e) Past and ongoing conservation measures for these species, their
habitats, or both.
(2) Threats and conservation actions affecting the species,
including:
(a) Factors that may be affecting the continued existence of the
species, which may include habitat modification or destruction,
overutilization, disease, predation, the inadequacy of existing
regulatory mechanisms, or other natural or manmade factors;
(b) Biological, commercial trade, or other relevant data concerning
any threats (or lack thereof) to these species; and
(c) Existing regulations or conservation actions that may be
addressing threats to these species.
(3) Additional information concerning the historical and current
status of these species, including whether any of the species may
warrant listing as a threatened species or may not warrant listing.
Please include sufficient information with your submission (such as
scientific journal articles or other publications) to allow us to
verify any scientific or commercial information you include.
Please note that submissions merely stating support for, or
opposition to, the action under consideration without providing
supporting information, although noted, do not provide substantial
information necessary to support a determination. Section 4(b)(1)(A) of
the Act directs that determinations as to whether any species is an
endangered or a threatened species must be made solely on the basis of
the best scientific and commercial data available.
You may submit your comments and materials concerning this proposed
rule by one of the methods listed in ADDRESSES. We request that you
send comments only by the methods described in ADDRESSES.
If you submit information via https://www.regulations.gov, your
entire submission--including any personal identifying information--will
be posted on the website. If your submission is made via a hardcopy
that includes personal identifying information, you may request at the
top of your document that we withhold this information from public
review. However, we cannot guarantee that we will be able to do so. We
will post all hardcopy submissions on https://www.regulations.gov.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on https://www.regulations.gov.
Because we will consider all comments and information we receive
during the comment period, our final determinations may differ from
this proposal. Based on the new information we receive (and any
comments on that new information), we may conclude that any of these
species are threatened instead of endangered, or we may conclude that
any of these species do not warrant listing as either an endangered
species or a threatened species.
Public Hearing
Section 4(b)(5) of the Act provides for a public hearing on this
proposal, if requested. Requests must be received by the date specified
in DATES. Such requests must be sent to the address shown in FOR
FURTHER INFORMATION CONTACT. We will schedule a public hearing on this
proposal, if requested, and announce the date, time, and place of the
hearing, as well as how to obtain reasonable accommodations, in the
Federal Register and local newspapers at least 15 days before the
hearing. We may hold the public hearing in person or virtually via
webinar. We will announce any public hearing on our website, in
addition to the Federal Register. The use of virtual public hearings is
consistent with our regulations at 50 CFR 424.16(c)(3).
Previous Federal Actions
On April 20, 2010, we received a petition from the Center for
Biological Diversity (CBD), Alabama Rivers Alliance, Clinch Coalition,
Dogwood Alliance, Gulf Restoration Network, Tennessee Forests Council,
and West Virginia Highlands Conservancy to list 404 aquatic, riparian,
and wetland species, including the Tennessee clubshell, Tennessee
pigtoe, and Cumberland moccasinshell, as endangered or threatened
species under the Act. In response to the petition, we published a
partial 90-day finding on September 27, 2011 (76 FR 59836), in which we
announced our finding that the petition contained substantial
information indicating that listing may be warranted for numerous
species, including the Tennessee clubshell, Tennessee pigtoe, and
Cumberland moccasinshell. This document serves as both our 12-month
warranted petition finding and our proposed rule to list these species.
Peer Review
A species status assessment (SSA) team prepared an SSA report for
the Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell. The SSA team was composed of Service biologists, in
consultation with other species experts. The SSA report represents a
compilation of the best scientific and commercial data available
concerning the status of the species, including the impacts of past,
present, and future factors (both negative and beneficial) affecting
the species. After the SSA report was completed, the methodology used
to evaluate the status of the three species was published in a peer-
reviewed journal (Fitzgerald et al. 2021, entire).
In accordance with our joint policy on peer review published in the
Federal Register on July 1, 1994 (59 FR 34270), and our August 22,
2016, memorandum updating and clarifying the role of peer review of
listing actions under the Act, we solicited independent scientific
review of the information contained in the SSA report. The Service sent
the SSA report to three independent peer reviewers and received one
response. Results of this structured peer review process can be found
at https://www.regulations.gov and the Asheville Ecological Services
Field Office (see FOR FURTHER INFORMATION CONTACT). In preparing this
proposed rule, we incorporated the results of this review, as
appropriate, into the SSA report, which is the foundation for this
proposed rule.
Summary of Peer Reviewer Comments
As discussed in Peer Review above, we received comments from one
peer reviewer on the draft SSA report. We reviewed all comments we
received from the peer reviewer for substantive issues and new
information regarding the information contained in the SSA report. The
peer reviewer agreed with our assessment of the status of the three
mussel species. All substantive comments from the peer reviewer
concerned the omission of coal mining as an important threat to the
three species and included a recommendation to add references from
peer-reviewed literature that illustrate the impact coal mining has had
on freshwater mussels
[[Page 57062]]
in the species' ranges. To address the reviewer's comment, in this
proposed rule, we clarify that our modeling approach focuses on
rangewide drivers of population conditions and does not capture some
site-specific threats with high consequences, such as coal mining. Coal
mining drainage affects, very roughly, less than half the historical
range of the three species. Because a little more than half of that
range lacks coal mining impacts, mining does not explain rangewide
patterns of population condition and was not included in the final
model. Our SSA report explains that the negative effects of mining on
mussels in this region have been well-documented, and the risk posed by
this threat must be considered in addition to the model estimates
presented, particularly for watersheds in the upper Tennessee and
Cumberland River basins. As recommended by the peer reviewer, in this
proposed rule, we include references from peer-reviewed literature that
explain how coal mining has affected mussels in the range of the three
mussel species.
I. Proposed Listing Determination
Background
General Mussel Biology
Freshwater mussels, including the three species that are the
subjects of this proposed rule, have a complex reproduction process
involving parasitic larvae, called glochidia, that are wholly dependent
on host fish. Mussels release sperm into the water column, which is
taken in by the female, wherein fertilization and development of
glochidia occurs in a restricted portion of the gills, called the brood
pouch or marsupium. When mature, the glochidia are released to the
water column to attach on the gills, head, or fins of fishes. Glochidia
die if they fail to attach to a host fish, attach to an incompatible
fish species, or attach to the wrong location on a host fish (Neves
1991, p. 254; Bogan 1993, p. 599). Once attached to the host, glochidia
draw nutrients from the fish's tissue as they develop (Arey 1932, pp.
214-215). Time to development, from attachment of glochidia to
maturation, ranges from just over 1 week to 6 weeks or more (Parmalee
and Bogan 1998, p. 8).
Depending on the species, mussels are either short-term or long-
term brooders. In short-term brooders, fertilization occurs in the
spring or summer and glochidia are released shortly after they are
fully developed. In long-term brooders, fertilization occurs in late
summer or fall, and developed glochidia are held over winter and
released in the following spring or summer (Haag 2012, pp. 39-40).
Mature glochidia drop off their hosts and, if they settle in suitable
habitat on the stream bottom, continue the remainder of their existence
as free-living mussels. Newly released glochidia are juveniles that are
reproductively immature but otherwise resemble adults, with both halves
(valves) of the shell developed and poised for growth.
Freshwater mussels are relatively sedentary and, under their own
power, capable of moving only short horizontal distances, typically up
to a few yards or less in a year (Haag 2012, pp. 34-35). Given mussels'
limited mobility, host fish are their primary mode of dispersal, and
the hosts are essential for maintaining population connectivity. Host
specificity varies, with some mussel species being compatible with a
few fish species while others can transform from glochidia to juveniles
on several fish species.
Tennessee Clubshell
A thorough review of the taxonomy, life history, and ecology of the
Tennessee clubshell is presented in the SSA report (Service 2020, pp.
3-7).
Attaining a maximum length of approximately 90 millimeters (mm) (4
inches (in)), the Tennessee clubshell is oval to triangular shaped and
has a tawny to brown shell, usually with wide, broken green rays
(Williams et al. 2008, p. 542). It occurs in the Tennessee and
Cumberland River drainages in Alabama, Georgia, Kentucky, North
Carolina, Tennessee, and Virginia (see figure 1, below). Favoring
moderately swift currents, it is found in riffles and shoals of small
streams to large rivers, in a mixture of sand, gravel, and cobble
substrates.
The Tennessee clubshell has a lifespan of 30 years on average but
may live to 50 years. Age at maturity ranges from 4 to 6 years. In
total, 10 host fish species in the minnow and darter families have been
documented by observations of either attachment or metamorphosis of
glochidia (Service 2020, pp. 5-6). As a short-term brooder, the
Tennessee clubshell spawns in the spring and releases glochidia mid-
July through early August.
[[Page 57063]]
[GRAPHIC] [TIFF OMITTED] TP22AU23.050
Tennessee Pigtoe
A thorough review of the taxonomy, life history, and ecology of the
Tennessee pigtoe is presented in the SSA report (Service 2020, pp. 3-
7).
Attaining a maximum length of 95 mm (3.7 in), the Tennessee
pigtoe's shape varies from oval to subtriangular or subquadrate, and
its shell is yellowish or brown, sometimes with dark green rays
(Williams et al. 2008, p. 585). It occurs in the Tennessee River
drainage, in Alabama, Georgia, North Carolina, Tennessee, and Virginia
(see figure 2, below). It is presumed extirpated from Mississippi,
where it was known to occur only in Bear Creek, in Tishomingo County.
Unlike the Tennessee clubshell and Cumberland moccasinshell, the
Tennessee pigtoe does not occur in the Cumberland River drainage. It is
found in moderate current, and rarely in pools and slackwaters, in
small streams to large rivers, in a mixture of sand, gravel, and cobble
substrates.
The Tennessee pigtoe has a lifespan of 30 years on average but may
live to 50 years. Age at maturity ranges from 4 to 6 years. As a short-
term brooder, it spawns in the spring and releases glochidia mid-July
through early August. The host fishes are unknown for this species but
likely are the same as or similar to those of the Tennessee clubshell.
[[Page 57064]]
[GRAPHIC] [TIFF OMITTED] TP22AU23.051
Cumberland Moccasinshell
A thorough review of the taxonomy, life history, and ecology of the
Cumberland moccasinshell is presented in the SSA report (Service 2020,
pp. 3-7).
Attaining a maximum length of 60 mm (2.4 in), the Cumberland
moccasinshell is elliptical shaped, slightly bowing or arching with
age. Its shell is yellowish to tawny or brown and usually covered in
green rays, and the posterior of the shell is usually marked with small
ridges (Williams et al. 2008, p. 434). The Cumberland moccasinshell
occurs in the Tennessee and Cumberland River drainages in Alabama,
Georgia, Kentucky, Tennessee, and Virginia (see figure 3, below). It is
presumed extirpated in North Carolina. Favoring strong currents, it is
found in riffles and shoals of streams ranging from headwaters to
medium-sized rivers amongst gravel, cobble, boulder, and occasionally
sand and gravel substrates. It is sometimes found under large flat
rocks or cracks in bedrock.
The Cumberland moccasinshell has a lifespan of approximately 10
years on average, with a maximum reported age of 24 years, based on
shells from the Clinch River in Virginia and Tennessee (Scott 1994, pp.
16, 71). Age at maturity ranges from 1 to 3 years (Zale and Neves 1982,
p. 19; T. Lane 2023, pers. comm.). Fish hosts include at least four
(possibly six) species in the darter genus, Etheostoma (Service 2020,
pp. 5-6). As a long-term brooder, the Cumberland moccasinshell spawns
mid-July and releases glochidia sporadically September through
November, with peak releases occurring January through May (Zale and
Neves 1982, p. 25).
[[Page 57065]]
[GRAPHIC] [TIFF OMITTED] TP22AU23.052
Regulatory and Analytical Framework
Regulatory Framework
Section 4 of the Act (16 U.S.C. 1533) and the implementing
regulations in title 50 of the Code of Federal Regulations set forth
the procedures for determining whether a species is an endangered
species or a threatened species, issuing protective regulations for
threatened species, and designating critical habitat for endangered and
threatened species. In 2019, jointly with the National Marine Fisheries
Service, the Service issued a final rule that revised the regulations
in 50 CFR part 424 regarding how we add, remove, and reclassify
endangered and threatened species and the criteria for designating
listed species' critical habitat (84 FR 45020; August 27, 2019). On the
same day, the Service also issued final regulations that, for species
listed as threatened species after September 26, 2019, eliminated the
Service's general protective regulations automatically applying to
threatened species the prohibitions that section 9 of the Act applies
to endangered species (84 FR 44753; August 27, 2019).
The Act defines an ``endangered species'' as a species that is in
danger of extinction throughout all or a significant portion of its
range, and a ``threatened species'' as a species that is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range. The Act requires that we
determine whether any species is an endangered species or a threatened
species because of any of the following factors:
(A) The present or threatened destruction, modification, or
curtailment of its habitat or range;
(B) Overutilization for commercial, recreational, scientific, or
educational purposes;
(C) Disease or predation;
(D) The inadequacy of existing regulatory mechanisms; or
(E) Other natural or manmade factors affecting its continued
existence.
These factors represent broad categories of natural or human-caused
actions or conditions that could have an effect on a species' continued
existence. In evaluating these actions and conditions, we look for
those that may have a negative effect on individuals of the species, as
well as other actions or conditions that may ameliorate any negative
effects or may have positive effects.
We use the term ``threat'' to refer in general to actions or
conditions that are known to or are reasonably likely to negatively
affect individuals of a species. The term ``threat'' includes actions
or conditions that have a direct impact on individuals (direct
impacts), as well as those that affect individuals
[[Page 57066]]
through alteration of their habitat or required resources (stressors).
The term ``threat'' may encompass--either together or separately--the
source of the action or condition or the action or condition itself.
However, the mere identification of any threat(s) does not
necessarily mean that the species meets the statutory definition of an
``endangered species'' or a ``threatened species.'' In determining
whether a species meets either definition, we must evaluate all
identified threats by considering the species' expected response and
the effects of the threats--in light of those actions and conditions
that will ameliorate the threats--on an individual, population, and
species level. We evaluate each threat and its expected effects on the
species, then analyze the cumulative effect of all of the threats on
the species as a whole. We also consider the cumulative effect of the
threats in light of those actions and conditions that will have
positive effects on the species, such as any existing regulatory
mechanisms or conservation efforts. The Secretary determines whether
the species meets the definition of an ``endangered species'' or a
``threatened species'' only after conducting this cumulative analysis
and describing the expected effect on the species now and in the
foreseeable future.
The Act does not define the term ``foreseeable future,'' which
appears in the statutory definition of ``threatened species.'' Our
implementing regulations at 50 CFR 424.11(d) set forth a framework for
evaluating the foreseeable future on a case-by-case basis. The term
``foreseeable future'' extends only so far into the future as we can
reasonably determine that both the future threats and the species'
responses to those threats are likely. In other words, the foreseeable
future is the period of time in which we can make reliable predictions.
``Reliable'' does not mean ``certain''; it means sufficient to provide
a reasonable degree of confidence in the prediction. Thus, a prediction
is reliable if it is reasonable to depend on it when making decisions.
It is not always possible or necessary to define the foreseeable
future as a particular number of years. Analysis of the foreseeable
future uses the best scientific and commercial data available and
should consider the timeframes applicable to the relevant threats and
to the species' likely responses to those threats in view of its life-
history characteristics. Data that are typically relevant to assessing
the species' biological response include species-specific factors such
as lifespan, reproductive rates or productivity, certain behaviors, and
other demographic factors.
Analytical Framework
The SSA report documents the results of our comprehensive
biological review of the best scientific and commercial data regarding
the status of these species, including an assessment of the potential
threats to the species. The SSA report does not represent our decision
on whether these species should be proposed for listing as endangered
or threatened species under the Act. However, it does provide the
scientific basis that informs our regulatory decisions, which involve
the further application of standards within the Act and its
implementing regulations and policies.
To assess the viability of the Tennessee clubshell, Tennessee
pigtoe, and Cumberland moccasinshell, 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, reduced
birth rates), 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 or biological environment
(for example, climate conditions, pathogens). In general, species
viability will increase with increases in resiliency, redundancy, and
representation (Smith et al. 2018, p. 306). Using these principles, we
identified the species' ecological requirements for survival and
reproduction at the individual, population, and species levels, and
described the beneficial and risk factors influencing the species'
viability.
The SSA process can be categorized into three sequential stages.
For each of the three species, during the first stage, we evaluated the
individual species' life-history needs. The next stage involved an
assessment of the historical and current condition of the species'
demographics and habitat characteristics, including an explanation of
how the species arrived at its current condition. The final stage of
the SSA involved making predictions about the species' responses to
positive and negative environmental and anthropogenic influences.
Throughout all of these stages, we used the best available information
to characterize viability as the ability of a species to sustain
populations in the wild over time. We use this information to inform
our regulatory decision.
The following is a summary of the key results and conclusions from
the SSA report; the full SSA report can be found at Docket No. FWS-R4-
ES-2023-0112 on https://www.regulations.gov and at the Service's
Environmental Conservation Online System species profile pages: https://ecos.fws.gov/ecp/species/3254; https://ecos.fws.gov/ecp/species/9887;
and https://ecos.fws.gov/ecp/species/9881.
Summary of Biological Status and Threats
In this discussion, we review the biological condition of these
species and their resources, and the threats that influence the
species' current and future conditions, in order to assess the species'
overall viability and the risks to that viability.
Species Needs
The Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell share similar habitat needs, preferring riffles, shoals,
and high gradient streams with stable substrates composed predominantly
of coarse sand, gravel, and cobble. Most often, the three species are
found in habitat less than 3 feet (0.9 meter) deep, in small to medium-
sized rivers. Larger, more inflated shell types of Tennessee clubshell
and Tennessee pigtoe inhabited large rivers prior to impoundment
(Ortmann 1918, pp. 534-538, 550-555), but representation of these shell
types has been lost, as both species, in addition to the Cumberland
moccasinshell, require free-flowing streams and are not viable (do not
successfully reproduce) in large impoundments, such as those along the
mainstem Tennessee and Cumberland rivers. Known and likely fish hosts
needed by each mussel species for reproduction are noted above (see
General Mussel Biology).
Analysis Units
For all three species, in our SSA, we used U.S. Geological Survey
(USGS) 10-digit hydrologic unit codes (HUCs, or watersheds; see figures
1-3, above) as analysis units for threats, current conditions, and
future conditions. These analysis units were selected because they
reflect relative differences in hydrologic conditions (e.g., separation
by major impoundments), and they were at the finest spatial scale for
which mussel survey data were available.
Threats
We provide information regarding present and future influences,
including both positive and negative, on the three
[[Page 57067]]
mussels' current and future viability, including large impoundments,
urban development, energy development, and agriculture, which have
altered natural flow regimes and/or diminished water and substrate
quality (Factor A). The existing regulatory mechanisms (Factor D) have
not been adequate to arrest the decline of the species. Additional
threats, including nonnative competitors and pathogens (which may be
responsible for enigmatic declines in some streams), likely have had
negative effects on the three mussel species, as described in the SSA
report and in a peer-reviewed publication on the SSA methodology
(Fitzgerald et al. 2021, entire). These additional threats may
negatively affect individuals of the species, but, unlike the primary
threats, these additional threats do not affect the species' overall
viability. Further, our analysis did not indicate that climate change
is a primary threat to the three species. While the rangewide effects
of climate change are likely to worsen in the future as droughts and
storms are projected to become more intense, the primary threats (large
impoundments, urban development, energy development, and agriculture)
are the main driver of the three species' status currently and into the
future.
We used a regression model to identify the threats affecting the
species. The model estimated the relative effects of a set of candidate
predictor variables (threats) on the mussels' current conditions (see
table 1, below). The threat variables retained for the regression
analysis were those that best predicted mussel persistence at the
rangewide scale. The analysis revealed the primary threats influencing
current conditions of the three species are erosion and sedimentation
from urban development and hydrologic alteration from large reservoirs
and urban development. Mean runoff, another variable that reflects the
impacts of erosion and sedimentation, was identified as a primary
threat only to the Cumberland moccasinshell; its influence on the other
two mussel species was not statistically significant.
Several threats (candidate variables in the model) were considered
as potential influences on current condition but were excluded from the
regression analysis because they decreased the model's ability to
detect the primary threats acting on the three mussel species rangewide
(see table 1, below). However, some of the excluded threats negatively
affect the three mussel species at smaller scales. In some watersheds
in the upper Tennessee Basin and Cumberland Basin, energy development,
which includes coal mining, natural gas, and oil extraction, has been
identified as key threats to mussels that have reduced habitat (see
``Energy Development--Coal, Natural Gas, and Oil,'' below).
Table 1--Summary of Major Threats Identified for Three Freshwater Mussel
Species, Including Proxy Variables Considered and Variables Retained in
the Final Model of Current Conditions of the Three Mussel Species
[Service 2020, p. 11]
------------------------------------------------------------------------
Proxy variables Variables in
Threats considered final model
------------------------------------------------------------------------
Hydrologic alteration......... Reservoir surface area Included.
Percentage developed Included.
land use.
Number and density of Not included.
dams.
Erosion and sedimentation..... Coefficient of Included.
variation mean
monthly precipitation.
Percentage developed Included.
land use.
Mean runoff........... Included.
Density of agriculture Included.
(crops and
pastureland).
Soil erodibility index Not included.
Climate change................ Coefficient of Included.
variation mean
monthly precipitation.
Mean monthly air Not included.
temperature.
Nutrient and chemical Percentage developed Included.
pollution. land use.
Density of agriculture Included.
(crops and
pastureland).
Percentage of mining Not included.
land use and number
of mines.
Stream km impaired Not included.
(EPA 303(d) and TMDL
lists \1\).
Nonnative competitors......... No suitable proxy for Not included.
competitive effects
identified.
------------------------------------------------------------------------
\1\ Section 303(d) of the Clean Water Act (33 U.S.C. 1251 et seq.)
authorizes the Environmental Protection Agency (EPA) to assist States,
Territories, and authorized Tribes in listing impaired waters and
developing total maximum daily loads (TMDLs) for these waterbodies. A
TMDL establishes the maximum amount of a pollutant allowed in a
waterbody and serves as the starting point or planning tool for
restoring water quality.
Large Impoundments
Our analysis identified large impoundments (indicated by reservoir
surface area) as a rangewide threat to the three mussel species. The
Tennessee Valley Authority operates 31 large dams in the Tennessee
River system and one large dam (Great Falls Dam) in the Cumberland
system (TVA Recreation Map website, 2023) and the U.S. Army Corps of
Engineers operates 10 large dams in the Cumberland system (USACE
Nashville District website, 2023). The effects of dams on aquatic
habitats and freshwater mussels are well-documented (Watters 2000, p.
261), and extinction and extirpations 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).
Dams disrupt population connectivity and alter water quality. After
a dam has been constructed, upstream the channel becomes deeper, flow
decreases dramatically, and fine sediments accumulate on the channel
bottom, which eliminates shoal and riffle habitats needed by the three
mussel species, as well as many others, and their host fishes.
Downstream of dams, natural flow regimes are disrupted by alternating
low flow releases and pulses of scouring flows (Hardison and Layzer
2001, p. 79), reduced water temperatures, reduced dissolved oxygen, and
changes in fish assemblages. Mussels may survive in cold tailwaters but
may not be able to reproduce, as was shown for native washboard mussels
(Megalonaias nervosa) in the mainstem Cumberland River (Heinricher and
Layzer 1999, entire). In a Cumberland River tributary, Caney Fork, the
extirpation of several mussel species, including Cumberland
moccasinshell, was attributed mainly to cold tailwater temperatures
from Center Hill Dam (completed in 1948) and
[[Page 57068]]
alteration of channel morphology from peaking flows, and no live
mussels were found within 7.5 mi (12 km) of the dam outfall (Layzer et
al. 1993, pp. 69-70).
Developed Land Use/Urbanization
For all three mussel species, development and urbanization
contribute to habitat degradation and loss. Freshwater mussel
populations may experience reduced abundance, species richness,
reproduction, growth, and survival stemming from the impacts of
urbanization on water and habitat quality (Diamond and Serveiss 2001,
p. 4716; Gangloff et al. 2009, p. 198; Cao et al. 2013, pp. 1212-1214;
Gillis et al. 2017, pp. 674-679). The threats analysis in our SSA found
the estimated probability of extirpation for all three species
approaches 100 percent when developed land area is between 9 and 15
percent of the total land area in a watershed (Service 2020, p. 61).
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.
Urbanization effects may include alterations to water quality, water
quantity, and instream and streamside habitat (Ren et al. 2003, p. 649;
Wilson 2015, p. 424). The effects on habitat also include 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).
In urbanized environments, storm drains deliver large volumes of
water to streams much faster than would naturally occur, often
resulting in flooding and bank erosion that reshape the channel and
cause substrate instability. 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. Once floodwaters recede, displaced individuals may be
left stranded out of the water, and fine sediments transported to the
stream settle on coarser substrates, which may damage or destroy areas
of mussel habitat. During storm events, contaminants in urbanized
environments (e.g., gasoline, oil drips, fertilizers) accumulated on
impervious surfaces may be washed directly into streams.
Energy Development--Coal, Natural Gas, and Oil
Extraction of coal, natural gas, and (to a lesser extent) oil is
common in the Cumberland and Upper Tennessee River basins and has been
associated with mussel declines in several watersheds (Layzer and
Anderson 1992, entire; Warren and Haag 2005, entire; Johnson et al.
2014, p. 890; TDEC 2014, p. 62; Zipper et al. 2016, pp. 612-613;
Ahlstedt et al. 2016, p. 13). Examples of energy development impacts in
the range of the three mussels include high levels of copper,
manganese, and zinc, metals that can be toxic to freshwater mussels,
found in sediment samples from both the Clinch and Powell Rivers. Both
rivers receive runoff from active, reclaimed, and abandoned coal mine
sites. In Cumberland Basin streams, including Buck Creek, Horse Lick
Creek, Little South Fork, and Rockcastle River, there was a clear
correlation between surface mines, increased metal concentrations
downstream, and the extirpation of some mussel species (Layzer and
Anderson 1992, pp. 91-96). In the upper Powell River, Virginia, coal
mining has almost eliminated the mussel fauna; sediment pore water from
the riverbed contains levels of contaminants potentially toxic to
mussels, particularly selenium and copper (Timpano et al. 2023, p. 13).
Natural gas and oil extraction is a threat to freshwater mussels in
the Upper Tennessee Basin and Cumberland Basin. In addition to the
general impacts of erosion and sedimentation from forest clearing for
access roads and installing drill pads, spills from (brine) disposal
ponds at gas wells or end-of-pipe discharges from brine treatment
facilities can reduce freshwater mussel abundance and diversity, as
well as increase mortality. These effects have been observed in the
Allegheny River (Patnode et al. 2015, p. 55), a watershed outside the
range of the three mussel species, but within the Ohio Basin, which
contains the Tennessee River and Cumberland River.
Agriculture
Agricultural activities are common throughout the range of the
three mussel species and have impacted watersheds in the species'
historical and current ranges. The advent of intensive row crop
agriculture is a potential factor in freshwater mussel decline and
species extirpation in the eastern United States (Peacock et al. 2005,
p. 550). Nutrient enrichment from fertilized crops and livestock is a
threat commonly associated with negative effects on aquatic biota and
can increase ammonia concentrations, to which freshwater mussels are
particularly sensitive. In addition, agricultural 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). Concentrations of these contaminants
from fields or pastures may be at levels that can affect an entire
population, especially given the highly fragmented distributions of the
three mussel species.
Agricultural land use has been associated with decreased freshwater
mussel diversity, growth, and survival in North American streams. A
temporal analysis of freshwater mussel populations in Iowa streams
showed declines in mussel species richness, and local extirpations
corresponded with agricultural intensity and forest clearing of the
riparian zone (Poole and Downing 2004, pp. 121-124). In those Iowa
streams, the segments with the highest substrate diversity exhibited
the lowest declines in species richness, indicating homogenization of
substrates from sedimentation is a freshwater mussel stressor. Further,
species richness increased or was unchanged where agriculture was less
than 25 percent of the land use. Another study, in Minnesota streams,
revealed decreases in mussel abundance and richness corresponding with
increases in agricultural land use (Hornbach et al. 2019, p. 1,833). In
Kentucky, streams in proximity to row crop agriculture were associated
with higher values of contaminants (pesticides and fertilizers), and
growth of caged mussels in those streams was low in comparison with
most other streams, where row crops were a minor land use (Haag et al.
2019, pp. 761-763). One of the streams in the study with high row crop
land use was the Red River, in the historical range of the Cumberland
moccasinshell and with one current low-condition population of the
Tennessee clubshell. The abnormally low growth rates observed in the
streams in proximity to high row crop land use usually presage early
mortality observed in mussel hatchery settings (Haag et al. 2019, p.
765).
Agencies such as the U.S. Department of Agriculture's Natural
Resources Conservation Service, along with State 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 the effects of agricultural practices, on aquatic
resources. These programs help identify opportunities for conservation
through projects such as exclusion fencing and alternate water supply
sources, which
[[Page 57069]]
help decrease nutrient inputs and keep livestock off stream banks and
shorelines, thus reducing erosion. However, the overall effectiveness
of these programs over a large scale is unknown given the three mussel
species' wide distribution and varying agricultural intensities.
Effects of the agricultural activities within the ranges of the
three mussel species, including diminishment of water quality and
habitat deterioration, are not often detected until after the
sedimentation and/or pesticide and herbicide inputs occur. In summary,
many effects of agricultural practices are pervasive across the ranges
of the three mussel species and are a factor in their historical
decline and localized extirpations.
Contaminants
Three of the land uses identified as threats to the three mussel
species (urban development, energy development, and agriculture)
contribute contaminants to stream habitats, which can degrade water and
substrate quality and adversely impact individuals and 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 contaminants such as metals, chlorine, and ammonia
on juvenile mussels are profound (Augspurger et al. 2003, p. 2,571;
Bartsch et al. 2003, p. 2,566). Among 69 aquatic organisms, the EPA
reported freshwater mussels (from tests on juveniles and glochidia)
were the taxonomic group most sensitive to ammonia (U.S. EPA 2013, pp.
24-27), which is a common contaminant in sewage plant discharges and
agricultural runoff. Juvenile mussels may readily ingest contaminants
adsorbed to sediment particles (Newton and Cope 2007, p. 276), and,
unlike adults, they feed in sediment pore water rather than on surface
water (Yeager et al. 1994, p. 221). Unionized ammonia in pore water was
clearly associated with recruitment failure in populations of eastern
elliptio (Elliptio complanata) mussels in the wild and was at
concentrations far below those found to be toxic in laboratory
experiments (Strayer and Malcom 2012, pp. 1,787-1,788).
Mussel glochidia 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). Even at low levels, certain heavy metals may inhibit glochidial
attachment to fish hosts. Contaminants have been shown to affect mussel
glochidia on the Clinch River (Goudreau et al. 1993, p. 221; Jacobson
et al. 1997, p. 2,386; Valenti et al. 2005, p. 1,243), which harbors
some of the best condition populations of the three species,
particularly the Cumberland moccasinshell.
Cadmium, chromium, copper, mercury, and zinc can negatively affect
biological processes of all mussel life stages (Havlik and Marking
1987, pp. 4-9; 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 destroyed a diverse
mussel fauna downstream of Saltville, Virginia (Brown et al. 2005, p.
1,459). Copper and zinc contamination originating from wastewater
discharges at a coal-fired electric power plant is one of the sources
of mussel declines in a reach of the Clinch River (Zipper et al. 2014,
p. 9). Despite localized improvements since these rivers initially were
contaminated, metals have remained in sediments, affecting recruitment
and densities of the mussel fauna for decades thereafter (Price et al.
2014, p. 12; Zipper et al. 2014, p. 9).
Threats Summary
In summary, the primary threats have curtailed the habitat and
range of the Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell, via flow alterations caused by large impoundments and
diminishment of water and substrate quality caused by various land
development activities. These threats, which result in both
contamination and the physical disruption of surface waters and
substrates, are the source of negative impacts to freshwater mussel
fauna, including the Tennessee clubshell, Tennessee pigtoe, and
Cumberland moccasinshell.
Current Conditions
The current resiliency of the Tennessee clubshell, Tennessee
pigtoe, and Cumberland moccasinshell was analyzed using demographic and
spatial distribution criteria (see table 2, below). Data for the
criteria are from quantitative and qualitative mussel surveys reported
in peer-reviewed literature, agency reports, and museum databases
(Service 2020, p. 8). Resiliency was classified as low, medium, or high
in the 10-digit HUC watersheds in each mussel species' historical
range. Demographic criteria consisted of categories of abundance or
density, and evidence of recent recruitment (inferred from the presence
of individuals less than or equal to 30 mm in shell length).
Distribution criteria were based on stream distance occupied within a
watershed.
Table 2--Criteria for Classifying Current Conditions of Populations Within Watersheds
[Service 2020, p. 10]
----------------------------------------------------------------------------------------------------------------
Demographic criteria
Condition ----------------------------------------- Distribution criteria Probability of
Abundance \1\ Reproduction persistence \2\
----------------------------------------------------------------------------------------------------------------
High......................... Abundant........ Evidence of Occurs in more than >0.75
reproduction. 50 river km.
Common.......... Increasing population
trend or evidence of
reproduction.
Medium....................... Abundant........ Decreasing population Occurs in 10-50 river 0.25-0.75
trend or no evidence km.
of reproduction.
Common.......... No information
available.
Rare............ Evidence of recent
reproduction.
Low.......................... Common.......... Decreasing trend or Occurs in less than <0.25
no evidence of 10 river km.
reproduction.
Rare............ Decreasing trend or
no evidence of
reproduction.
-----------------------------------------
Presence-absence data only.
-----------------------------------------
[[Page 57070]]
Unknown...................... Historical records of occurrence in Subwatershed (HUC10)
watershed with no surveys in past 30 lacking site-
years. specific surveys in
watershed (HUC8) of
known occurrence.
-----------------------------------------
Extirpated................... No live or fresh dead individuals No areas known to be
collected in surveys within the past currently occupied
30 years. within watershed.
----------------------------------------------------------------------------------------------------------------
\1\ In this column, abundant is defined as more than 500 individuals reported or densities greater than 0.70 per
square meter (m\2\); common is defined as 100-500 individuals reported or densities between 0.10-0.70/m\2\;
and rare is defined as fewer than 100 individuals reported or densities fewer than 0.10/m\2\.
\2\ Probability of persistence represents expected risk of extirpation over 30 years (roughly 3 generations),
with numeric estimates selected based on best professional judgment of freshwater mussel experts.
Mussel records were considered current if they included detection
of live individuals or fresh dead shells (with soft tissue attached)
since 1988. Watersheds containing only records before 1988 were
considered extirpated if recent surveys had not encountered live
individuals or no suitable habitat was available (e.g., large
impoundments), and unknown if no recent surveys (since 1988) were
conducted. This approach represents an underestimate of decline, as
only watersheds with confirmed records were considered historically
occupied. Because early surveys did not always record exact localities
and many watersheds faced hydrologic alterations prior to comprehensive
sampling, actual historical ranges (still confined to the Cumberland
and/or Tennessee Basin) were likely greater than those represented in
figure 2 of the SSA report (Service 2020, p. 13). In addition, sampling
has not occurred in a standardized manner, and many watersheds with
unknown current conditions may reflect experts' opinions that these
regions are unlikely to support viable populations (i.e., sample
selection bias). This suggests that upper values of estimated range
reductions (74 percent, 76 percent, and 62 percent for the Cumberland
moccasinshell, Tennessee clubshell, and Tennessee pigtoe, respectively)
may better represent current conditions of these species (see table 3,
below). Early surveys of freshwater mussels often recorded qualitative
descriptions of abundance (e.g., rare, common, widespread) that make
direct comparison of current abundance estimates impossible; however,
it is widely accepted in the literature that dramatic reductions from
historical abundance have occurred throughout the ranges of these
species.
In the absence of sufficient genetic data to confirm spatial
population structure, we treated each watershed as a population for our
analyses of species conditions. Watersheds were nested within two major
units of representation, the Cumberland River basin and the Tennessee
River basin. For each of the three species, redundancy was
characterized by the number of populations, and, in our analysis, range
loss incorporates redundancy as the portion of watersheds where the
species is extirpated (see table 3, below). Although populations in low
condition contribute to redundancy values, they have minimal influence
on population resiliency and species representation. Low-condition
populations are not, or are barely, recruiting individuals to found new
generations and, therefore, are functionally extirpated.
Table 3--Current Resiliency of All Watersheds (Populations), and Range Loss (Percent of Watersheds Where Extirpated)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Current resiliency
Species -------------------------------------------------------------------------------- Range loss
Extirpated Low Medium High Unknown (percent)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tennessee clubshell..................................... 83 28 4 3 29 58-76
Tennessee pigtoe........................................ 51 32 8 3 20 42-62
Cumberland moccasinshell................................ 87 22 3 9 29 56-74
--------------------------------------------------------------------------------------------------------------------------------------------------------
Tennessee Clubshell--Current Conditions
The Tennessee clubshell historically occurred throughout the
Tennessee and Cumberland River basins. Currently, it occupies 35 to 64
watersheds, compared to 147 historically, reflecting a range reduction
of 58 to 76 percent. Most extant populations of the species are
classified as low condition (28), with only three populations
classified as high condition and four populations classified as medium
condition, indicating species condition is currently low (see table 3,
above). Rangewide, there are three redundant populations with high
resiliency, which are likely to withstand the effects of stochastic
events, and five redundant populations with medium resiliency, which
may withstand the effects of a stochastic event. The 28 low-condition
(low resiliency) populations have little capacity to withstand the
effects of a stochastic event and do not contribute to species
redundancy or the species' capacity for withstanding catastrophic
events. While the Tennessee clubshell persists in the Tennessee River
basin, it is on the verge of extirpation from the entire Cumberland
River basin, with only 5 low-condition populations (low resiliency) and
16 extirpated populations. Extirpation of the species from this basin
would result in a 50 percent loss in representation, as the Tennessee
clubshell would be lost from one of the two major ecological settings
(representation units) in its range.
[[Page 57071]]
Representation has been further diminished by reductions in
connectivity between mainstem and tributary streams, which contribute
to reduced size and genetic isolation of Tennessee clubshell
populations.
Tennessee Pigtoe--Current Conditions
The Tennessee pigtoe was once a common species throughout the
Tennessee Basin. Currently, it occupies 43 to 63 watersheds, compared
to 114 historically, reflecting a range reduction of 42 to 62 percent.
Most extant populations of the species are classified as low condition
(32), with only three populations classified as high condition and
eight populations classified as medium condition, indicating species
condition is currently low (see table 3, above). Rangewide, there are
three redundant populations with high resiliency, which are likely to
withstand the effects of stochastic events, and eight redundant
populations with medium resiliency, which may withstand the effects of
a stochastic event. The 32 low-condition (low resiliency) populations
have little capacity to withstand the effects of a stochastic event and
do not contribute to species redundancy or the species' capacity for
withstanding catastrophic events. Representation of the Tennessee
pigtoe has declined, as populations in the mainstem Tennessee River are
extirpated and the connectivity between tributaries is disrupted by
impoundments, which has diminished population interaction necessary for
maintenance of genetic diversity.
Cumberland Moccasinshell--Current Conditions
The Cumberland moccasinshell historically occurred throughout the
Tennessee and Cumberland River basins. Currently it occupies 34 to 63
watersheds, compared to 150 historically, reflecting a range reduction
of 56 to 74 percent. Most extant populations of the species are
classified as low condition (22), with nine populations classified as
high condition and three populations classified as medium condition,
indicating species condition is currently low (see table 3, above).
With nine populations in high condition and two populations in medium
condition in the Tennessee Basin, redundancy in the basin may buffer
against stochastic events. However, these populations are concentrated
in Upper Tennessee Basin tributaries, mainly the Clinch-Powell
watershed, with seven high condition populations, and one high
condition population in the Holston watershed. The Duck River
watershed, in the lower Tennessee Basin, has one high-condition and two
medium-condition populations. The low-condition populations in the rest
of the Tennessee Basin lack resiliency and have little capacity to
withstand effects of environmental stochasticity. Because there are no
populations with high resiliency, and only one population with medium
resiliency in the Cumberland basin ecological setting, and smaller-
scale ecological settings outside the Upper Tennessee and Duck basins
only contain populations with low resiliency, Cumberland moccasinshell
representation, or its potential for adapting to environmental change,
is diminished.
Current Risk Profiles
We used the model parameters estimated in the current conditions
analysis (i.e., the relative effects of each stressor) to model the
probability that a watershed would be classified as extirpated, low,
medium, or high based on historical land-use and climate patterns.
These probabilities discussed in the ``Future Conditions'' section of
our SSA report (Service 2020, pp. 16-20) represent the species' present
(or baseline; i.e., current) risk profile with no additional climate or
land-use changes. The baseline modeling, based on threats alone,
measures the present extirpation risk to all populations regardless of
their current condition. For example, there may be populations that
have a comparatively high demographic and distributional condition, but
due to significant stressors that are already acting on the population,
such as large impoundments and isolation, they also have a high
probability of extirpation. Additionally, because low-condition
populations contain few individuals or display little evidence of
recruitment), they have an inherently high risk of extirpation within
several generations. Importantly, these baseline estimates are not
impacted by uncertainty in future climate or land-use scenarios because
they derive from currently observed patterns across the landscape.
These baseline probabilities are assumed valid over the next 10 years.
Therefore, we used the current or baseline probability to assess the
current risk of extirpation or low condition to each of the three
mussel species (see table 4, below).
The current risk of being classified as extirpated or low condition
for all three species was similar. For Tennessee clubshell, the average
current risk of being classified as extirpated or low condition is 0.71
and 0.23, respectively. In addition, nearly all populations of
Tennessee clubshell may be at high risk of being classified as
extirpated or low condition due to current land use. For Tennessee
pigtoe, the average current risk of being classified as extirpated or
low condition is 0.54 and 0.34, respectively. In addition, all
populations of Tennessee pigtoe were more likely than not to be
classified as extirpated or low condition based on current patterns of
land use within watersheds. For Cumberland moccasinshell, the average
current risk of being classified as extirpated or low condition is 0.72
and 0.16, respectively. The current risk of being classified as
extirpated or low condition was similarly high for Cumberland
moccasinshell populations in the lower Tennessee and throughout the
Cumberland Basin as described for Tennessee pigtoe; however, the upper
Tennessee Basin currently contains eight populations classified as high
condition that may have lower risk of becoming extirpated or low
condition populations compared to other regions.
Table 4--Average Current Probability (Baseline or Current Risk Profile) of Species Condition Across All
Watersheds Given Current Threats
----------------------------------------------------------------------------------------------------------------
Species Extirpated Low Medium High
----------------------------------------------------------------------------------------------------------------
Tennessee Clubshell............................. 0.71 0.23 0.04 0.03
Tennessee Pigtoe................................ 0.54 0.34 0.06 0.05
Cumberland Moccasinshell........................ 0.72 0.16 0.04 0.08
----------------------------------------------------------------------------------------------------------------
Future Conditions
Because we determined that the current condition of the Tennessee
clubshell, Tennessee pigtoe, and Cumberland moccasinshell is consistent
with an endangered species (see Determination of Status for the Three
Mussel Species, below), we are not presenting the results of the future
[[Page 57072]]
scenarios in this proposed rule. However, above, we present the
baseline or current risk profile results as these were used in the
determination of the three species' status. Please refer to the SSA
report (Service 2020, pp. 16-21) for the full analysis of future
scenarios.
We note that, by using the SSA framework to guide our analysis of
the scientific information documented in the SSA report, we have not
only analyzed individual effects on the three 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 three species. To assess the
current and future condition of the three 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. For each of the three species, because the
SSA framework considers not just the presence of the factors, but to
what degree they collectively influence risk to the entire species, our
assessment integrates the cumulative effects of the factors and
replaces a standalone cumulative effects analysis.
Conservation Efforts and Regulatory Mechanisms
Existing conservation measures directly benefiting the three mussel
species are limited. Five percent or less of the currently occupied
area for all three species is within protected areas managed for
biodiversity conservation (Service 2020, pp. 27-29). While the percent
of areas receiving some level of protection is slightly greater (15
percent or less), many of these areas are subject to mining and other
extractive uses detrimental to freshwater mussels. Compared to
currently extant populations of the three species, the percentage of
protected area is similar for extirpated populations, suggesting the
levels of protection observed are not adequate to prevent local
extirpations.
Reintroductions have been attempted for at least three populations
of Cumberland moccasinshell using individuals translocated from the
Clinch River at Kyles Ford, Tennessee, to other rivers in the State.
Between 2010 and 2015, 1,100 individuals were stocked in the Emory
River, and 3,539 individuals were stocked in the Nolichucky River
(Phipps et al. 2018, pp. 27-41). Populations of the Cumberland
moccasinshell in both rivers are currently in low condition and do not
appear to be reproducing based on 2016 surveys. An additional 800
individuals were stocked in the Hiwassee River in 2012 (Phipps et al.
2018, pp. 26-27), but reintroduction efforts were not successful, and
this population is currently considered extirpated. It is possible that
cold-water discharges from Apalachia Dam, which is operated as a
peaking hydropower facility, have reduced the reintroduction potential
of mussel species in the Hiwassee River. Unnatural thermal regimes
continue to affect populations of Tennessee clubshell in the Hiwassee
River and freshwater mussels below other hydropower dams in the
Tennessee River basin (Layzer and Scott 2006, p. 488).
States vary in level of protection provided to freshwater mussels
in general. The State of Virginia has statutory protection for
freshwater mussels. State wildlife management agencies in Alabama,
Tennessee, North Carolina, and Kentucky have protective regulatory
measures prohibiting the take or possession of freshwater mussels
without a scientific collector's permit. Freshwater mussel species are
only protected in Georgia if they are listed under the Act.
Accordingly, they currently may be taken with a fishing license or
commercial fishing license. A variety of additional ``designations'' or
status descriptions are assigned to the three species within States of
occurrence; however, these do not indicate State statutory protections,
nor are they associated with habitat or restoration priorities.
Determination of Status for the Three Mussel Species
Section 4 of the Act (16 U.S.C. 1533) and its implementing
regulations (50 CFR part 424) set forth the procedures for determining
whether a species meets the definition of an endangered species or a
threatened species. The Act defines an ``endangered species'' as a
species in danger of extinction throughout all or a significant portion
of its range, and a ``threatened species'' as a species likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range. The Act requires that we
determine whether a species meets the definition of an endangered
species or a threatened species because of any of the following
factors: (A) The present or threatened destruction, modification, or
curtailment of its habitat or range; (B) overutilization for
commercial, recreational, scientific, or educational purposes; (C)
disease or predation; (D) the inadequacy of existing regulatory
mechanisms; or (E) other natural or manmade factors affecting its
continued existence.
Status Throughout All of Its Range
After evaluating threats to the species and assessing the
cumulative effects of the threats under the Act's section 4(a)(1)
factors, we found that the three mussel species have declined
significantly in distribution and abundance. The primary broadscale
threats, development (as urbanization) and large impoundments, and more
localized threats, including energy development and agriculture, have
reduced available habitat, curtailing the range of the three species
(Factor A). All three species have experienced substantial reductions
in their current distributions compared to historical ranges.
Our SSA modeled the current probability (i.e., baseline or current
risk profile) that the species' status within various watersheds would
be extirpated, low, medium, or high (see table 4, above) based on
historical land-use and climate patterns, which account for the
rangewide primary threats as discussed above. Together, the model
(baseline or current risk profile) and current population conditions
analysis (which is based on observations in the wild and current
threats) informed our determination as to whether each species is in
danger of extinction throughout all or a significant portion of its
range (i.e., whether each species meets the definition of an endangered
species under the Act). Our determinations for each species are
discussed below.
Tennessee Clubshell--Status Throughout All of Its Range
The Tennessee clubshell historically occurred throughout the
Tennessee and Cumberland River basins. Most extant populations of the
Tennessee clubshell are in low condition (have low resiliency) and
exhibit little to no reproduction. Recruitment of new generations to
the low-condition populations is very unlikely, and, as such, they are
functionally extirpated, with little resistance to stochastic events,
and they are unlikely to recover under the chronic stresses of current
and projected threats. The three high-condition populations are
restricted to the upper Tennessee River basin, in the Clinch River (two
watersheds) and Hiwassee River (one watershed). In the Cumberland Basin
representation unit, 5 populations are in low condition, and 16 are
extirpated. As discussed above, while the Tennessee clubshell persists
in the Tennessee River basin, it is on the verge of extirpation from
the entire
[[Page 57073]]
Cumberland River basin, with only 5 low-condition populations and 16
extirpated populations. Extirpation of the species from this basin
would result in a 50 percent loss in representation. Representation has
been further diminished by reductions in connectivity between mainstem
and tributary streams, which contribute to reduced size and genetic
isolation of Tennessee clubshell populations.
Because species viability is bolstered by having a broad spatial
distribution across ecological settings (representation) and a
sufficient number of resilient populations (redundancy), the
restriction of few resilient populations to one region, in comparison
to the broader distribution of populations historically, indicates
species viability is currently low. In addition, the average current
risk of extirpation (0.71) or low condition (0.23) across all
watersheds for the Tennessee clubshell is high. Given the preponderance
of low condition populations that are likely functionally extirpated
throughout the species' range and the extent of urban development and
large impoundments throughout the range, as well as more localized
threats, including energy development and agriculture, the Tennessee
clubshell is in danger of extinction throughout its range. Unlike a
threatened species, which is likely to become an endangered species
within the foreseeable future throughout all or a significant portion
of its range, the Tennessee clubshell is in danger of extinction
throughout its range now, owing to the low condition of most
populations and their current high risk of extirpation resulting from
current threats. Thus, after assessing the best available information,
we determine that Tennessee clubshell is in danger of extinction
throughout all of its range.
Tennessee Clubshell--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
within the foreseeable future throughout all or a significant portion
of its range. We have determined that the Tennessee clubshell is in
danger of extinction throughout all of its range and accordingly did
not undertake an analysis of any significant portion of its range.
Because the Tennessee clubshell warrants listing as endangered
throughout all of its range, our determination does not conflict with
the decision in Center for Biological Diversity v. Everson, 435 F.
Supp. 3d 69 (D.D.C. 2020) (Everson), which vacated the provision of the
Final Policy on Interpretation of the Phrase ``Significant Portion of
Its Range'' in the Endangered Species Act's Definitions of ``Endangered
Species'' and ``Threatened Species'' (Final Policy; 79 FR 37578, July
1, 2014) providing that if the Service determines that a species is
threatened throughout all of its range, the Service will not analyze
whether the species is endangered in a significant portion of its
range.
Determination of Status for the Tennessee Clubshell
Our review of the best available scientific and commercial
information indicates that the Tennessee clubshell meets the Act's
definition of an endangered species. Therefore, we propose to list the
Tennessee clubshell as an endangered species in accordance with
sections 3(6) and 4(a)(1) of the Act.
Tennessee Pigtoe--Status Throughout All of Its Range
Once a common species in the Tennessee Basin, most extant
populations of the Tennessee pigtoe are in low condition (have low
resiliency) and exhibit little to no reproduction. Recruitment of new
generations to the low-condition populations is very unlikely, and, as
such, they are functionally extirpated, with little resistance to
stochastic events, and they are unlikely to recover under the chronic
stresses of current and projected threats. Two of the three high-
condition populations are in the upper part of the basin, in a Clinch
River subwatershed and one of the river's tributaries, Copper Creek.
The other high-condition population is in the lower Tennessee system,
in the Duck River basin. Eight populations are in medium condition and
distributed among lower, middle, and upper Tennessee Basin watersheds.
The Tennessee pigtoe may have sufficiently resilient populations
(redundancy) spread over a large enough area to withstand a
catastrophic event due to the occurrence in eight watersheds by either
a high-condition or medium-condition population (three high-condition
and eight medium-condition). However, populations in the mainstem
Tennessee River, where the phenotype with a larger, more inflated shell
only occurred, are extirpated. In addition, numerous large impoundments
on the mainstem Tennessee and several of its tributaries prevent gene
flow between populations, which is necessary for maintaining
representation. The average current risk of extirpation across all
watersheds for the Tennessee pigtoe is high (0.54) based on current
patterns of land use within the watersheds. Therefore, the 11
populations in high and medium condition may be at high risk of
becoming extirpated or low condition in the future given current land
use and population trajectories. While the reduction in range (42 to 62
percent) appears slightly smaller for the Tennessee pigtoe when
compared to the Cumberland moccasinshell and the Tennessee clubshell,
this may reflect the Tennessee pigtoe's endemism to the Tennessee Basin
and naturally smaller distribution rather than differences in the
species' response to major stressors. Given the extent of urban
development and large impoundments, and more localized but widespread
threats of energy development and agriculture, most populations of the
Tennessee pigtoe are in low condition such that they are at high risk
of extirpation. Unlike a threatened species, which is likely to become
an endangered species within the foreseeable future throughout all or a
significant portion of its range, the Tennessee pigtoe is in danger of
extinction throughout its range now, owing to the low condition of most
populations and their current high risk of extirpation resulting from
current threats. Thus, after assessing the best available information,
we determine that the Tennessee pigtoe is in danger of extinction
throughout all of its range.
Tennessee Pigtoe--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
within the foreseeable future throughout all or a significant portion
of its range. We have determined that the Tennessee pigtoe is in danger
of extinction throughout all of its range and accordingly did not
undertake an analysis of any significant portion of its range. Because
the Tennessee pigtoe warrants listing as endangered throughout all of
its range, our determination does not conflict with the decision in
Everson, which vacated the provision of the Final Policy (79 FR 37578;
July 1, 2014) providing that if the Service determines that a species
is threatened throughout all of its range, the Service will not analyze
whether the species is endangered in a significant portion of its
range.
Determination of Status for the Tennessee Pigtoe
Our review of the best available scientific and commercial
information indicates that the Tennessee pigtoe meets the Act's
definition of an endangered species. Therefore, we propose to list the
Tennessee pigtoe as
[[Page 57074]]
an endangered species in accordance with sections 3(6) and 4(a)(1) of
the Act.
Cumberland Moccasinshell--Status Throughout All of Its Range
Historically occurring throughout the Tennessee and Cumberland
Basins, most extant populations of the Cumberland moccasinshell are in
low condition (have low resiliency) and exhibit little to no
reproduction. Recruitment of new generations to the low-condition
populations is very unlikely, and, as such, they are functionally
extirpated, with little resistance to stochastic events, and they are
unlikely to recover under the chronic stresses of current and projected
threats. Nine populations are in high condition, with seven occupying
the Clinch River drainage and one occupying a watershed in the North
Fork Holston River drainage, both in the Upper Tennessee Basin. One
high-condition population and two medium-condition populations are in
the Duck River watershed. In the Cumberland Basin representation unit,
1 population is in medium condition, 7 are in low condition, and 20 are
extirpated. The average current risk of extirpation across all
watersheds for the Cumberland moccasinshell is high (0.72).
Containing eight of the nine high-condition populations rangewide,
the Upper Tennessee Basin is a stronghold for the species. However, in
the Upper Tennessee, there is uncertainty around population condition,
for which mean risk of extirpation or low-condition population ranges
from 0.5 to 0.8. The stronghold status of the Upper Tennessee Basin and
the presence of one high-condition and two medium-condition populations
in the Lower Tennessee Basin's Duck River, and another medium-condition
population in the Cumberland Basin, indicate the species has some
capacity to withstand a catastrophic event, although species redundancy
is greatly reduced from historical levels.
Although currently nine populations are in high condition, they are
isolated by large impoundments and the hundreds of river miles between
the three river systems where they occur. This isolation prohibits
genetic exchange between populations, which is essential to maintaining
adaptive capacity (representation); therefore, the average risk of
extirpation or low condition is high (greater than 0.5) for most of the
high-condition populations. Additionally, the level of current
rangewide threats to the species, which have contributed to documented
extirpation from 87 of 150 watersheds, is projected to remain
relatively constant, suggesting population trajectories are unlikely to
change. Considering watersheds of unknown condition are likely
extirpated and instead are classified as ``unknown'' due to being
excluded from surveys because of poor habitat quality, the number of
extirpations is likely closer to 106 of the 150 watersheds. The current
level and extent of threats has resulted in a low-condition or
extirpated state for most populations of the Cumberland moccasinshell,
such that these populations are at a high risk of extirpation. Unlike a
threatened species, which is likely to become an endangered species
within the foreseeable future throughout all or a significant portion
of its range, the Cumberland moccasinshell is in danger of extinction
throughout its range now, owing to the low condition of most
populations and their current high risk of extirpation resulting from
current threats. Thus, after assessing the best available information,
we determine that the Cumberland moccasinshell is in danger of
extinction throughout all of its range.
Cumberland Moccasinshell--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
within the foreseeable future throughout all or a significant portion
of its range. We have determined that the Cumberland moccasinshell is
in danger of extinction throughout all of its range and accordingly did
not undertake an analysis of any significant portion of its range.
Because the Cumberland moccasinshell warrants listing as endangered
throughout all of its range, our determination does not conflict with
the decision in Everson, which vacated the provision of the Final
Policy (79 FR 37578; July 1, 2014) providing that if the Service
determines that a species is threatened throughout all of its range,
the Service will not analyze whether the species is endangered in a
significant portion of its range.
Determination of Status for the Cumberland Moccasinshell
Our review of the best available scientific and commercial
information indicates that the Cumberland moccasinshell meets the Act's
definition of an endangered species. Therefore, we propose to list the
Cumberland moccasinshell as an endangered species in accordance with
sections 3(6) and 4(a)(1) of the Act.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened species under the Act include recognition as a listed
species, planning and implementation of recovery actions, requirements
for Federal protection, and prohibitions against certain practices.
Recognition through listing results in public awareness, and
conservation by Federal, State, Tribal, and local agencies, private
organizations, and individuals. The Act encourages cooperation with the
States and other countries and calls for recovery actions to be carried
out for listed species. The protection required by Federal agencies,
including the Service, and the prohibitions against certain activities
are discussed, in part, below.
The primary purpose of the Act is the conservation of endangered
and threatened species and the ecosystems upon which they depend. The
ultimate goal of such conservation efforts is the recovery of these
listed species, so that they no longer need the protective measures of
the Act. Section 4(f) of the Act calls for the Service to develop and
implement recovery plans for the conservation of endangered and
threatened species. The goal of this process is to restore listed
species to a point where they are secure, self-sustaining, and
functioning components of their ecosystems.
The recovery planning process begins with development of a recovery
outline made available to the public soon after a final listing
determination. The recovery outline guides the immediate implementation
of urgent recovery actions while a recovery plan is being developed.
Recovery teams (composed of species experts, Federal and State
agencies, nongovernmental organizations, and stakeholders) may be
established to develop and implement recovery plans. The recovery
planning process involves the identification of actions that are
necessary to halt and reverse the species' decline by addressing the
threats to its survival and recovery. The recovery plan identifies
recovery criteria for review of when a species may be ready for
reclassification from endangered to threatened (``downlisting'') or
removal from protected status (``delisting''), and methods for
monitoring recovery progress. Recovery plans also establish a framework
for agencies to coordinate their recovery efforts and provide estimates
of the cost of implementing recovery tasks. Revisions of the plan may
be done to address continuing or new threats to the species, as new
[[Page 57075]]
substantive information becomes available. For each of the three
species, the recovery outlines, draft recovery plans, final recovery
plans, and any revisions will be available on our website (https://ecos.fws.gov/ecp/species/3254; https://ecos.fws.gov/ecp/species/9887;
and https://ecos.fws.gov/ecp/species/9881) or from our Asheville
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT)
as they are completed.
Implementation of recovery actions generally requires the
participation of a broad range of partners, including other Federal
agencies, States, Tribes, nongovernmental organizations, businesses,
and private landowners. Examples of recovery actions include habitat
restoration (e.g., restoration of native vegetation), research, captive
propagation and reintroduction, and outreach and education. The
recovery of many listed species cannot be accomplished solely on
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires
cooperative conservation efforts on private, State, and Tribal lands.
If these species are listed, funding for recovery actions will be
available from a variety of sources, including Federal budgets, State
programs, and cost-share grants for non-Federal landowners, the
academic community, and nongovernmental organizations. In addition,
pursuant to section 6 of the Act, the States of Alabama, Georgia,
Kentucky, North Carolina, Tennessee, and Virginia would be eligible for
Federal funds to implement management actions that promote the
protection or recovery of the Tennessee clubshell, Tennessee pigtoe,
and Cumberland moccasinshell. Information on our grant programs that
are available to aid species recovery can be found at: https://www.fws.gov/service/financial-assistance.
Although the Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell are only proposed for listing under the Act at this time,
please let us know if you are interested in participating in recovery
efforts for these species. Additionally, we invite you to submit any
new information on these species whenever it becomes available and any
information you may have for recovery planning purposes (see FOR
FURTHER INFORMATION CONTACT).
Section 7(a) of the Act requires Federal agencies to evaluate their
actions with respect to any species that is proposed or 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) states that each Federal action agency shall, in
consultation with the Secretary, ensure that any action they authorize,
fund, or carry out is not likely to jeopardize the continued existence
of a listed species or result in the destruction or adverse
modification of designated critical habitat. Each Federal agency shall
review its action at the earliest possible time to determine whether it
may affect listed species or critical habitat. If a determination is
made that the action may affect listed species or critical habitat,
formal consultation is required (50 CFR 402.14(a)), unless the Service
concurs in writing that the action is not likely to adversely affect
listed species or critical habitat. At the end of a formal
consultation, the Service issues a biological opinion, containing its
determination of whether the Federal action is likely to result in
jeopardy or adverse modification.
In contrast, section 7(a)(4) of the Act requires Federal agencies
to confer with the Service on any action which is likely to jeopardize
the continued existence of any species proposed to be listed under the
Act or result in the destruction or adverse modification of critical
habitat proposed to be designated for such species. Although the
conference procedures are required only when an action is likely to
result in jeopardy or adverse modification, action agencies may
voluntarily confer with the Service on actions that may affect species
proposed for listing or critical habitat proposed to be designated. In
the event that the subject species is listed or the relevant critical
habitat is designated, a conference opinion may be adopted as a
biological opinion and serve as compliance with section 7(a)(2) of the
Act.
Examples of discretionary actions for the Tennessee clubshell,
Tennessee pigtoe, and Cumberland moccasinshell that may be subject to
the section 7 processes are land management or other landscape-altering
activities on Federal lands administered by the National Park Service,
U.S. Fish and Wildlife Service, or U.S. Forest Service, as well as
actions on State, Tribal, local, or private lands that require a
Federal permit (such as a permit from the U.S. Army Corps of Engineers
under section 404 of the Clean Water Act (33 U.S.C. 1251 et seq.) or a
permit from the Service under section 10 of the Act) or that involve
some other Federal action (such as funding from the Federal Highway
Administration, Federal Aviation Administration, or Federal Emergency
Management Agency). Federal actions not affecting listed species or
critical habitat--and actions on State, Tribal, local, or private lands
that are not federally funded, authorized, or carried out by a Federal
agency--do not require section 7 consultation. Federal agencies should
coordinate with the local Service Field Office (see FOR FURTHER
INFORMATION CONTACT) with any specific questions.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to endangered wildlife.
The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR
17.21, make it illegal for any person subject to the jurisdiction of
the United States to commit, to attempt to commit, to solicit another
to commit or to cause to be committed any of the following: (1) import
endangered wildlife into, or export from, the United States; (2) take
(which includes harass, harm, pursue, hunt, shoot, wound, kill, trap,
capture, or collect, or to attempt to engage in any such conduct)
endangered wildlife within the United States or on the high seas; (3)
possess, sell, deliver, carry, transport, or ship, by any means
whatsoever, any such wildlife that has been taken illegally; (4)
deliver, receive, carry, transport, or ship in interstate or foreign
commerce in the course of commercial activity; or (5) sell or offer for
sale in interstate or foreign commerce. Certain exceptions to these
prohibitions apply to employees or agents of the Service, the National
Marine Fisheries Service, other Federal land management agencies, and
State conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving endangered wildlife under certain circumstances. Regulations
governing permits are codified at 50 CFR 17.22. With regard to
endangered wildlife, a permit may be issued for the following purposes:
for scientific purposes, to enhance the propagation or survival of the
species, and for incidental take in connection with otherwise lawful
activities. The statute also contains certain exemptions from the
prohibitions, which are found in sections 9 and 10 of the Act.
It is the policy of the Service, as published in the Federal
Register on July 1, 1994 (59 FR 34272), to identify, to the extent
known at the time a species is listed, specific activities that would
not be considered likely to result in violation of section 9 of the
Act. To the extent possible, activities that would be considered likely
to result in violation will also be identified in as specific a manner
as possible. The intent of this policy is to increase public
[[Page 57076]]
awareness of the effect of a proposed listing on proposed and ongoing
activities within the ranges of the species proposed for listing.
As discussed above, certain activities that are prohibited under
section 9 may be permitted under section 10 of the Act. In addition, to
the extent currently known, the following activities would not be
considered likely to result in violation of section 9 of the Act if we
list the Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell:
(1) Normal agricultural and silvicultural practices, which are
carried out in accordance with any existing regulations and best
management practices; and
(2) Normal residential landscape activities.
This list is intended to be illustrative and not exhaustive;
additional activities that would not be considered likely to result in
violation of section 9 of the Act may be identified during coordination
with the local field office, and in some instances (e.g., with new
information), the Service may conclude that one or more activities
identified here would be considered likely to result in violation of
section 9.
To the extent currently known, the following is a list of examples
of activities that would be considered likely to result in violation of
section 9 of the Act, in addition to what is already clear from the
descriptions of the prohibitions found at 50 CFR part 17, if we list
the Tennessee clubshell, Tennessee pigtoe, and Cumberland
moccasinshell:
(1) Unauthorized handling or collecting of the species;
(2) Modification of the channel or water flow of any stream in
which the Tennessee clubshell, Tennessee pigtoe, or Cumberland
moccasinshell is known to occur;
(3) Livestock grazing that results in direct or indirect
destruction of stream habitat; and
(4) Discharge of chemicals or fill material into any waters in
which the Tennessee clubshell, Tennessee pigtoe, or Cumberland
moccasinshell is known to occur.
This list is intended to be illustrative and not exhaustive;
additional activities that would be considered likely to result in
violation of section 9 of the Act may be identified during coordination
with the local field office, and in some instances (e.g., with new or
site-specific information), the Service may conclude that one or more
activities identified here would not be considered likely to result in
violation of section 9 of the Act. Questions regarding whether specific
activities would constitute violation of section 9 of the Act should be
directed to the Asheville Ecological Services Field Office (see FOR
FURTHER INFORMATION CONTACT).
II. Critical Habitat
Background
Critical habitat is defined in section 3 of the Act as:
(1) The specific areas within the geographical area occupied by the
species, at the time it is listed in accordance with the Act, on which
are found those physical or biological features
(a) Essential to the conservation of the species, and
(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.
We have found critical habitat to be prudent and determinable for
all three mussel species and have drafted a proposed critical habitat
rule for these species. However, the proposed critical habitat rule is
proceeding on a different timeline from the proposed listing rule
because we were informed on August 9, 2023, that the Office of
Information and Regulatory Affairs (OIRA) in the Office of Management
and Budget (OMB) had determined that our proposed critical habitat rule
is significant under Executive Order 12866 and will be initiating the
interagency review process for that proposed rule. Because the Service
is operating under a court-enforceable deadline requiring us to submit
the 12-month finding to the Federal Register by August 15, 2023, and
because E.O. 12866 does not apply to listing determinations, we are
proceeding with publishing this finding and proposed rule without the
proposed critical habitat designation. We will publish a proposed
critical habitat rule for the three mussels following interagency
review of the proposed critical habitat rule.
Required Determinations
Clarity of the Rule
We are required by E.O.s 12866 and 12988 and by the Presidential
Memorandum of June 1, 1998, to write all rules in plain language. This
means that each rule we publish must:
(1) Be logically organized;
(2) Use the active voice to address readers directly;
(3) Use clear language rather than jargon;
(4) Be divided into short sections and sentences; and
(5) Use lists and tables wherever possible.
If you feel that we have not met these requirements, send us
comments by one of the methods listed in ADDRESSES. To better help us
revise the rule, your comments should be as specific as possible. For
example, you should tell us the numbers of the sections or paragraphs
that are unclearly written, which sections or sentences are too long,
the sections where you feel lists or tables would be useful, etc.
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
Regulations adopted pursuant to section 4(a) of the Act are exempt
from the National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et
seq.) and do not require an environmental analysis under NEPA. We
published a notice outlining our reasons for this determination in the
Federal Register on October 25, 1983 (48 FR 49244). This includes
listing, delisting, and reclassification rules, as well as critical
habitat designations. In a line of cases starting with Douglas County
v. Babbitt, 48 F.3d 1495 (9th Cir. 1995), the courts have upheld this
position.
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), E.O. 13175 (Consultation and Coordination
with Indian Tribal Governments), and the Department of the Interior's
manual at 512 DM 2, we readily acknowledge our responsibility to
communicate meaningfully with recognized Federal Tribes on a
government-to-government basis. In accordance with Secretary's Order
3206 of June 5, 1997 (American Indian Tribal Rights, Federal-Tribal
Trust Responsibilities, and the Endangered Species Act), we readily
acknowledge our responsibilities to work directly with Tribes in
developing programs for healthy ecosystems, to acknowledge that Tribal
lands are not subject to the same controls as Federal public lands, to
remain sensitive to Indian culture, and to make information available
to Tribes.
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).
[[Page 57077]]
Authors
The primary authors of this proposed rule are the staff members of
the Fish and Wildlife Service's Species Assessment Team and the
Asheville Ecological Services Field Office.
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Plants,
Reporting and recordkeeping requirements, Transportation, Wildlife.
Proposed Regulation Promulgation
Accordingly, we propose to amend part 17, subchapter B of chapter
I, title 50 of the Code of Federal Regulations, as set forth below:
PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, unless
otherwise noted.
0
2. In Sec. 17.11, in paragraph (h), amend the List of Endangered and
Threatened Wildlife by adding entries for ``Clubshell, Tennessee'',
``Moccasinshell, Cumberland'', and ``Pigtoe, Tennessee'' 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
----------------------------------------------------------------------------------------------------------------
* * * * * * *
Clubshell, Tennessee............ Pleurobema oviforme Wherever found..... E [Federal Register
citation when
published as a final
rule]
* * * * * * *
Moccasinshell, Cumberland....... Medionidus Wherever found..... E [Federal Register
conradicus. citation when
published as a final
rule]
* * * * * * *
Pigtoe, Tennessee............... Pleuronaia Wherever found..... E [Federal Register
barnesiana. citation when
published as a final
rule]
* * * * * * *
----------------------------------------------------------------------------------------------------------------
* * * * *
Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-17844 Filed 8-21-23; 8:45 am]
BILLING CODE 4333-15-P