Rule2022-21579
Endangered and Threatened Wildlife and Plants; Removing the Snail Darter From the List of Endangered and Threatened Wildlife
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
October 5, 2022
Effective
November 4, 2022
Issuing agencies
Interior DepartmentFish and Wildlife Service
Abstract
We, the U.S. Fish and Wildlife Service (Service), are removing the snail darter (Percina tanasi), a small freshwater fish native to the Tennessee River watershed, from the Federal List of Endangered and Threatened Wildlife (List). This final rule is based on a thorough review of the best available scientific and commercial information which indicates that the threats to the species have been reduced or eliminated to the point that it has recovered and is no longer in danger of extinction or likely to become in danger of extinction in the foreseeable future. Therefore, the species no longer meets the definition of an endangered or a threatened species under the Endangered Species Act of 1973, as amended (Act).
Full Text
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<title>Federal Register, Volume 87 Issue 192 (Wednesday, October 5, 2022)</title>
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[Federal Register Volume 87, Number 192 (Wednesday, October 5, 2022)]
[Rules and Regulations]
[Pages 60298-60313]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2022-21579]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2020-0152; FF09E22000 FXES11130900000 212]
RIN 1018-BE62
Endangered and Threatened Wildlife and Plants; Removing the Snail
Darter From the List of Endangered and Threatened Wildlife
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are removing
the snail darter (Percina tanasi), a small freshwater fish native to
the Tennessee River watershed, from the Federal List of Endangered and
Threatened Wildlife (List). This final rule is based on a thorough
review of the best available scientific and commercial information
which indicates that the threats to the species have been reduced or
eliminated to the point that it has recovered and is no longer in
danger of extinction or likely to become in danger of extinction in the
foreseeable future. Therefore, the species no longer meets the
definition of an endangered or a threatened species under the
Endangered Species Act of 1973, as amended (Act).
DATES: This rule is effective November 4, 2022.
ADDRESSES: This final rule, the post-delisting monitoring plan, and
supporting documents (including the recovery plan and 5-year review
summary) are available on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a>
under Docket No. FWS-R4-ES-2020-0152 or at <a href="https://ecos.fws.gov">https://ecos.fws.gov</a>.
FOR FURTHER INFORMATION CONTACT: Daniel Elbert, Field Supervisor, U.S.
Fish and Wildlife Service, Tennessee Ecological Services Field Office,
446 Neal Street, Cookeville, TN 38506; telephone 931-528-6481. Direct
all questions or requests for additional information to ``SNAIL DARTER
QUESTIONS'' at the address above. Individuals in the United States who
are deaf, deafblind, hard of hearing, or have a speech disability may
dial 711 (TTY, TDD, or TeleBraille) to access telecommunications relay
services. Individuals outside the United States should use the relay
services offered within their country to make international calls to
the point-of contact in the United States.
SUPPLEMENTARY INFORMATION:
Executive Summary
Why we need to publish a rule. Under the Act, a species may warrant
removal from the Federal List of Endangered and Threatened Wildlife
(i.e., ``delisting'') if it no longer meets the definition of an
endangered species or a threatened species. Delisting a species can
only be completed by issuing a rule through the Administrative
Procedure Act rulemaking process.
What this document does. We are delisting the snail darter (Percina
tanasi) based on its recovery. The prohibitions and conservation
measures provided by the Act, particularly through sections 7 and 9,
will no longer apply to the snail darter.
The basis for our action. Under the Act, we may determine that a
species is an endangered species or a 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 threats
to the species have been reduced or eliminated so that the snail darter
no longer meets the definition of an endangered or threatened species
under the Act.
Under the Act, we must review the status of all listed species at
least once every 5 years. We must delist a species if we determine, on
the basis of the best available scientific and commercial data, that
the species is neither a threatened species nor an endangered species.
Our regulations at 50 CFR 424.11 identify three reasons why we might
determine that a listed species is neither an endangered species nor a
threatened species: (1) The species is extinct; (2) the species has
recovered, or (3) the original data used at the time the species was
classified were in error. Here, we have determined that the snail
darter has recovered; therefore, we are delisting it.
Peer review and public comment. We evaluated the species' needs,
current conditions, and future conditions to support our September 1,
2021, proposed rule to delist the snail darter (86 FR 48953). We sought
comments from independent specialists to ensure that our determination
is based on scientifically sound data, assumptions, and analyses. We
invited these peer reviewers to comment on the proposed rule and draft
post-delisting monitoring plan. We considered all comments and
information we received during the public comment period on the
proposed rule when developing this final rule.
Previous Federal Actions
On October 9, 1975, we published a final rule in the Federal
Register (40 FR 47505) listing the snail darter as an endangered
species due to the threat of
[[Page 60299]]
the impoundment of the only known location of the species by the
completion of Tellico Dam. On April 1, 1976, the Service designated
16.5 miles (26.4 km) of the lower Little Tennessee River as critical
habitat for the snail darter (41 FR 13926). In 1977, the critical
habitat for the snail darter was amended to include a map (42 FR
47840). The Snail Darter Recovery Team prepared the initial recovery
plan for the snail darter on April 4, 1979 (Hurst et al. 1979, entire).
The plan was revised and finalized on May 5, 1983 (Service 1983,
entire). Due to successful translocations into the Hiawassee and
Holston Rivers and the discovery of additional populations, we
reclassified the snail darter from endangered to threatened and
rescinded critical habitat on July 5, 1984 (49 FR 27510). In 2013, we
completed a 5-year review for the snail darter. No change in the
species' listing classification was recommended as a result of that 5-
year review. We initiated a second 5-year review for the species on
April 11, 2019 (84 FR 14669), and on July 16, 2019, we were petitioned
to delist the snail darter. We were already reviewing the status of the
species as part of the 5-year review and, upon receiving the petition,
determined that there was substantial scientific and commercial
information indicating the delisting the snail darter may be warranted.
On September 1, 2021, we published a proposed rule to remove the snail
darter from the Federal List of Endangered and Threatened Wildlife (86
FR 48953) and announced the availability of a draft post-delisting
monitoring plan. The September 1, 2021, proposed rule to delist the
snail darter also serves as our 5-year review, and 90-day and 12-month
findings on the petition.
Summary of Changes From the Proposed Rule
We considered all comments and information that we received during
the comment period for the proposed rule to delist the snail darter (86
FR 48953; September 1, 2021). We made minor editorial changes and
revised various sections of the rule based on public and partner
comments. We also incorporated an additional study (Jones et al. 2015)
into our evaluation of the effects of climate change on the species.
The information from this study added to the evidence of variability in
the weather but did not change our understanding of how climate change
will affect the snail darter overall.
Background
Taxonomy
The snail darter is a small fish in the perch family, Percidae, and
darter subfamily, Etheostomatinae. The species was first discovered in
1973 (Starnes 1977, p. 1). At that time, and when listed in 1975, the
snail darter was recognized as a new, undescribed species in the genus
Percina and subgenus Imostoma. The species was described in 1976 as
Percina tanasi, named after the historic Cherokee town of Tanasi, near
where the snail darter was first discovered (Etnier 1976, p. 485). The
snail darter has been recognized as the sister species (closest
relative) to the stargazing darter (P. uranidea) (Etnier 1976, p. 480;
Near and McEachran 2002, p. 8).
Population Genetics
No studies have been completed to determine the level of gene flow
between populations or the amount of potential inbreeding within
populations. Because snail darters are often found in the lower
portions of tributaries, it is likely that tributary populations are
part of larger mainstem metapopulations (Service 2013, p. 13). It is
not clear to what level the mainstem populations are isolated by the
large Tennessee Valley Authority (TVA) dams and reservoirs.
Species Description
The following description is modified from Etnier (1976, pp. 480-
485) and Etnier and Starnes (1993, pp. 587-590). The snail darter is a
small benthic (bottom-dwelling) fish that grows to 3.55 inches (in) (90
millimeters (mm)). The base color is brown or brownish grey with some
green. The back has four clear black or dark brown saddle markings.
These markings extend down the sides toward the series of blotches
along the lateral line. A dark suborbital bar or ``teardrop'' marking
is present below the eye. Fin rays are usually speckled, but pelvic and
anal fins are sometimes clear. Males gain a blue-green sheen on the
sides and belly during the breeding season when golden flecks become
more pronounced on the cheeks and pectoral fins. Females also develop
some gold coloring but are less bright than the males. Breeding
tubercles (small bony protrusions) form on the rays of the elongated
anal fin of males as well as the lower surfaces of rays of the pelvic
fins, caudal (tail) fin, and branchiostegal (soft gill cover under
head) rays.
The snail darter may occur with two other Imostoma darters, the
river darter (Percina shumardi) and the saddleback darter (P. vigil).
The snail darter differs from the river darter by having four saddle
markings along its back, while the latter lacks saddles altogether.
Snail darters and river darters are often found together, but river
darters tend to be associated with slightly larger substrate than snail
darters (Matthews 2020, pers. comm.). While these species may share
similar habitat, there is no evidence that they compete for resources.
Habitat
The snail darter occurs in flowing sections of medium to large
rivers. In these streams, snail darters are predominantly found over
clean gravel without significant silt or plant coverage (Ashton and
Layzer 2010, p. 615). Initially thought to require shallow, unimpounded
portions of river to survive (Starnes 1977, pp. 21-23), snail darters
were later found in the impounded but flowing upper sections of
mainstem Tennessee River reservoirs (Hickman and Fitz 1978, p. 80).
Snail darters were found in shoals at a depth of 1 to 3 feet (ft) (0.3
to 1 meters (m)) (Starnes 1977, pp. 21-33; Ashton and Layzer 2010,
entire). Snail darters have also been found on gravel and cobble
patches in up to 25 ft (7.6 m) of water with regular captures at 10 to
15 ft (3 to 5 m) deep (Ripley 1976, entire; Hickman and Fitz 1978, pp.
80-83; Matthews 2017, pers. comm.; Matthews 2019, pers. comm.). In
addition to large river habitats, snail darters also occupy the lower
reaches of larger creeks, and during the breeding season, large numbers
of darters congregate on the gravel shoals in these creeks to spawn
(Starnes 1977, p. 64). Detailed descriptions of snail darter habitat
can be found in Ashton and Layzer (2010, entire) and Starnes (1977, pp.
21-33).
Life History
The life history data presented here are modified from Etnier and
Starnes (1993, p. 588), with additions from Hickman and Fitz (1978, pp.
10-38) and Starnes (1977, entire). The snail darter is well adapted to
its habitat of clean gravel substrate in large creeks and rivers. The
saddle markings on the back of the fish act as camouflage amongst
gravel and small cobble, and are a pattern seen in other benthic
species (Armbruster and Page 1996, pp. 250-252). Snail darters also can
burrow into the substrate with just their eyes exposed to escape
predation (Etnier and Starnes 1993, p. 588). The species spawns in the
late winter and early spring, from about February to April. Adults
gather on shoals during the breeding season. While spawning has not
been directly observed, it is likely
[[Page 60300]]
that the eggs are buried shallowly in the sand and gravel similar to
how other Percina species bury their eggs. Females produce about 600
eggs per season during multiple spawning events. Eggs hatch after 15-20
days and produce pelagic (in the water column) larvae that drift
considerable distances downstream. The developing larvae and juveniles
likely use relatively calm deeper areas of rivers and reservoirs. By
the end of summer, juveniles are about 1.6 in (40 mm) in length and
begin migrating upstream. Some fast-growing individuals may reach
sexual maturity in their first year, but most mature in their second
year (Etnier and Starnes 1993, p. 588). Snail darters are short-lived
fish that rarely survive to their fourth year. As their name implies,
snail darters mostly feed on freshwater snails, predominantly in the
genera Leptoxis and Lithasia, as well as caddisfly and dipteran (true
fly) larvae (Etnier and Starnes 1993, p. 588).
Distribution
When we listed the snail darter (40 FR 47505; October 9, 1975), the
species was only known from about 13 miles (21 kilometers (km)) of the
lower Little Tennessee River in Loudoun County, Tennessee. Shortly
thereafter, the species was found in the Watts Bar Reservoir portion of
the Tennessee River below the mouth of the Little Tennessee River, and
efforts were made to conserve the species by translocating individuals
into other suitable streams (Hickman and Fitz 1978, pp. 80-83). Snail
darters were collected from the Little Tennessee River and stocked into
the Hiwassee, Holston, Nolichucky, and Elk Rivers beginning in 1975 to
achieve this objective. The introductions into the Nolichucky and Elk
Rivers were halted when sharphead darters (Etheostoma acuticeps), a
species once thought extinct, were rediscovered there, causing concern
about competition between the two species. However, the introductions
into the Holston and Hiwassee Rivers were successful, and it is thought
that the populations in the French Broad and Ocoee Rivers were
established by dispersal from these populations (Ashton and Layzer
2008, pp. 55-56). These locations are presented on a map in figure 1,
below.
After the completion of Tellico Dam on the Little Tennessee River,
snail darters were located in five additional tributaries and three
reservoirs: Little River (1983), Big Sewee Creek (1981), Chickamauga
Reservoir (1976), Nickajack Reservoir (1981), South Chickamauga Creek
(Tennessee and Georgia portions) (1980), Guntersville Reservoir
(Tennessee portion) (1981), Sequatchie River (1981), and Paint Rock
River (Alabama portion) (1981) (Service 1983, pp. 12-19; Service 2013,
p. 7). A survey in 2005 located the species in seven of the nine
tributaries surveyed: French Broad River, Hiwassee River, Holston
River, Little River, Sequatchie River, Big Sewee Creek, and South
Chickamauga Creek (Ashton and Layzer 2008, p. 54). This survey appears
to be the last known record of snail darters in Big Sewee Creek
(Simmons 2019, unpublished data). In this survey, snail darters were
not located in the Paint Rock River or Ocoee River, though they were
discovered at both locations in later years (Kuhajda 2018, unpublished
data). In 2007, a single snail darter was collected in Citico Creek,
suggesting that snail darters may have persisted in the Little
Tennessee River watershed after the dam was constructed; however, they
were not found in follow-up surveys (Service 2013, p. 7).
More recent survey efforts have continued to document new snail
darter locations, though with limited information on persistence. In
2012, two snail darters were collected in the Flint River in Alabama
(Simmons 2019, p. 1), but they have not been found there since. In
2015, snail darters were collected in the Elk River in Alabama and in
Bear Creek in Alabama and Mississippi, over 100 river miles (160 km)
from the Flint River location. To verify these collections, TVA began
an effort to survey the mainstem Tennessee River reservoirs for snail
darters (Simmons 2019, p. 2), collecting snail darters from six
reservoirs in Tennessee and Alabama: Chickamauga, Nickajack,
Guntersville, Wheeler, Pickwick, and the French Broad River arm of Fort
Loudoun Reservoir (Simmons 2019, p. 7; TVA unpublished data). Later
surveys of the reservoirs located juvenile snail darters in Watts Bar
Reservoir (Matthews 2020, pers. comm.), but trawling efforts did not
locate individuals in Tellico, Wilson, and Kentucky Reservoirs (Simmons
2019, p. 6).
In 2017 and 2018, an environmental DNA survey was conducted for
snail darters in the Alabama portion of the Tennessee River Basin
(Shollenberger 2019, p. 6). Environmental DNA (eDNA) is a surveillance
tool used to monitor for the genetic presence of an aquatic species.
These surveys returned positive eDNA detections in the following
streams and reservoirs where TVA surveys had physically collected snail
darters during previous survey efforts: Guntersville Reservoir, Wheeler
Reservoir, Paint Rock River, Elk River, Pickwick Reservoir, and Bear
Creek. The eDNA surveys returned negative results at locations where
snail darters had not been collected recently, such as Wilson Reservoir
and the Flint River, although an eDNA detection was found and then
validated in 2020 in Shoal Creek, a tributary to Wilson Reservoir
(Johnson 2020, p. 2).
In summary, the snail darter's known range has greatly expanded
since it was first discovered (see figure 1, below). At the time of
listing in 1975, the species was only known from a small reach of the
Little Tennessee River. By the early 1980s, new populations had been
found or established in 10 widely dispersed locations, and in 1984, we
reclassified the snail darter from an endangered to a threatened
species (49 FR 27510; July 5, 1984), due largely to an increased number
of populations and a considerable range expansion. Since 2010,
populations in an additional two reservoirs and three tributaries have
been discovered (Simmons 2019, pp. 1-2). As a result, snail darters are
now considered extant in seven mainstem reservoirs of the Tennessee
River (Fort Loudoun, Watts Bar, Chickamauga, Nickajack, Guntersville,
Wheeler, and Pickwick) and 12 tributaries in the Tennessee River
watershed (Holston River, French Broad River, Little River, Hiwassee
River, Ocoee River, South Chickamauga Creek, Sequatchie River, Paint
Rock River, Flint River (two individuals), Elk River, Shoal Creek (one
individual), and Bear Creek). We consider the snail darter extirpated
from the Little Tennessee River mainstem, Citico Creek, and Sewee
Creek, and never established in the Nolichucky River.
BILLING CODE 4333-15-P
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[GRAPHIC] [TIFF OMITTED] TR05OC22.038
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BILLING CODE 4333-15-C
Evaluating Populations
The best available scientific information does not allow us to
determine population size for the snail darter. Therefore, our
assessment was based on monitoring of the stream community conducted by
TVA throughout the Tennessee River Basin using an index of biotic
integrity (IBI) approach. The IBI uses fish community metrics, such as
percent insectivore, to develop a score of stream health. These surveys
target a representative sample of the overall fish assemblage rather
than individual species, so are not designed to provide population size
information on rare species but are useful for determining species
persistence at a site. Occasional encounters by IBI monitoring crews
provide information in the intervening years, but many of these surveys
took place in wadable portions of streams, missing the deeper water
habitats often used by the species. Where snail darters are common near
IBI sites, surveyors intentionally avoid their habitat to reduce the
probability of injury, which can result in artificially reduced numbers
of the species in samples. The wide variety of methods used during
previous survey efforts also makes comparing populations difficult.
Surveys targeted at other species only note incidental sightings of
snail darters, not density, and the TVA trawls have mostly been carried
out to determine the species' presence and range (Simmons 2019, p. 1).
However, the best available science indicates that reproducing
populations of the species likely exist in at least 16 locations (6
reservoirs and 10 tributaries) based on repeated collections that have
been made at those locations, evidence of multiple age classes at those
locations (i.e., suggesting regular recruitment into the population),
and multiple males and females captured at those locations (see tables
1 and 2 in Summary of Biological Status, below).
Recovery and Recovery Plan Implementation
Section 4(f) of the Act (16 U.S.C. 1531 et seq.) directs us to
develop and implement recovery plans for the conservation and survival
of endangered and threatened species unless we determine that such a
plan will not promote the conservation of the species. Under section
4(f)(1)(B)(ii), recovery plans must, to the maximum extent practicable,
include objective, measurable criteria which, when met, would result in
a determination, in accordance with the provisions of section 4 of the
Act, that the species be removed from the List.
Recovery plans provide a roadmap for us and our partners on methods
of enhancing conservation and minimizing threats to listed species, as
well as measurable criteria against which to evaluate progress towards
recovery and assess the species' likely future condition. However, they
are not regulatory documents and do not substitute for the
determinations and promulgation of regulations required under section
4(a)(1) of the Act. A decision to revise the status of a species, or to
delist a species, is ultimately based on an analysis of the best
scientific and commercial data available and consideration of the
standards listed in 50 CFR 424.11(e) to determine whether a species is
no longer an endangered species or a threatened species, regardless of
whether that information differs from the recovery plan.
There are many paths to accomplishing recovery of a species, and
recovery may be achieved without all of the criteria in a recovery plan
being fully met. For example, one or more criteria may be exceeded
while other criteria may not yet be accomplished. In that instance, we
may determine that the threats are minimized sufficiently and that the
species is robust enough that it no longer meets the definition of an
endangered species or a threatened species. In other cases, we may
discover new recovery opportunities after having finalized the recovery
plan. Parties seeking to conserve the species may use these
opportunities instead of methods identified in the recovery plan.
Likewise, we may learn new information about the species after we
finalize the recovery plan. The new information may change the extent
to which existing criteria are appropriate for identifying recovery of
the species. The recovery of a species is a dynamic process requiring
adaptive management that may, or may not, follow all of the guidance
provided in a recovery plan.
The snail darter recovery plan (Service 1983, entire) included
recovery criteria to indicate when threats to the species have been
adequately addressed and prescribed actions that were thought to be
necessary for achieving those criteria. We summarize the criteria and
then discuss progress toward meeting the recovery criteria in the
following sections.
Recovery Criteria
The objective of the recovery plan is to protect and recover the
snail darter to the point where it can be removed from the Federal List
of Endangered and Threatened Wildlife. The recovery plan states that
the species ``shall be considered recovered when one of the
alternatives (A, B, or C) listed below is met and no present or
foreseeable threats exist that could cause the species to become in
danger of extinction'' (Service 1983, p. 27).
<bullet> Alternative A: Suitable habitat areas of the Tennessee
River within the area from the backwaters of Wheeler Reservoir upstream
to the headwaters of Watts Bar Reservoir are inhabited by snail darter
populations that can survive and reproduce independently of tributary
rivers as evidenced by documented reproduction in Watts Bar Reservoir
or some other Tennessee River reservoir.
<bullet> Alternative B: More Tennessee River tributary populations
of the species are discovered, and existing populations are not lost.
The number of additional populations needed to meet this criteria would
vary depending on the status of the new populations, but two
populations similar to the Big Sewee Creek, South Chickamauga Creek, or
Sequatchie River populations, or one comparable to the Hiwassee River
population, would denote recovery.
<bullet> Alternative C: Through maintenance of existing populations
and/or by expansion of these populations, there exist viable
populations of snail darters in five separate streams such as Big Sewee
Creek, Hiwassee River, South Chickamauga Creek, Sequatchie River and
Paint Rock River. (For this alternative, ``viable populations'' means
that population monitoring over a 10-year period (biannual sampling)
indicates that the snail darter is reproducing (at least two year
classes present each year sampled) and that the population is either
stable or expanding. For some populations, existing data may be used to
meet this requirement.)
Achievement of Recovery Criteria
Alternative A of the recovery criteria requires that snail darters
be present in suitable habitats within reservoirs from Wheeler
Reservoir upstream to Watts Bar Reservoir and evidence of reproduction
within reservoirs independent of tributaries in at least one reservoir.
We conclude that Alternative A has been met based on collection of
seven permanent mainstem populations (Pickwick, Wheeler, Guntersville,
Nickajack, Chickamauga, Watts Bar, and Fort Loudoun reservoirs) and
evidence of reproduction independent of tributaries in Chickamauga,
Nickajack, and Wheeler reservoirs (see tables 1 and 2 in Summary of
Biological Status,
[[Page 60303]]
below, and figure 1 in Background, above). These populations represent
multiple reservoirs, rivers and span at least three physiographic
regions (Highland Rim, Cumberland Plateau, and Ridge and Valley)
(Etnier and Starnes 1993, p. 3; Mettee et al. 1996, p. 5).
Our assessment of the tributary populations of snail darters
supports the determination that Alternative B has also been met.
Alternative B of the recovery criteria requires the discovery or
establishment of at least two new tributary populations similar to the
Big Sewee Creek, South Chickamauga Creek, or Sequatchie River
populations or one comparable to the Hiwassee River population. In our
analysis, we determined that 10 tributary populations are extant that
have a moderate or high resilience (see table 1, below). Four of these
(French Broad River, Ocoee River, Elk River, and Bear Creek) have been
found or established since the recovery plan was finalized. The largest
new population occurs in the lower French Broad River. The founders of
this population were likely migrants or juveniles from the stocked
population in the Holston (Service 2013, p. 14). Snail darters have
been collected across at least 21.8 miles (35.1 km) of the French Broad
River and across 19 miles (30.5 km) of the Hiwassee River (Ashton and
Layzer 2008, pp. 54-55; Kuhajda 2018, supplementary data; TVA,
unpublished data). Therefore, the requirement to discover or establish
a population comparable to the Hiwassee River population has been met.
Additionally, Alternative B gives the option of two tributary
populations comparable to Big Sewee Creek, South Chickamauga Creek, and
Sequatchie River. The current populations in the Ocoee River and Bear
Creek are comparable to the Big Sewee Creek, South Chickamauga Creek,
and Sequatchie River populations that existed at the time the recovery
plan was finalized based on captures and occupied stream length.
Since 2011, snail darters have been found consistently in the Ocoee
River by TVA IBI crews, appearing in every biannual sample since 2015.
Snail darters have been collected across 5.9 miles (9.5 km) of the
Ocoee River, and collections of snail darters in the Hiwassee River
near the mouth of the Ocoee suggest that they may occupy more of the
river.
Snail darters have only been collected as individuals or pairs, but
the lower portion of Bear Creek is in the Gulf Coastal Plain
physiographic region, so preferred habitat is more limited than in
other streams. Individuals have been collected across 5.8 miles (9.3
km) of Bear Creek, but trawling collections near the mouth of Bear
Creek and eDNA detections in the lower parts of the Bear Creek system
and at its mouth suggest that snail darters may occur in an additional
25 miles (40 km) of the creek (Simmons 2019, supplementary data;
Shollenberger 2019, pp. 14-16).
Since 2015, snail darters have been collected in 1.4 miles (2.3 km)
of the Elk River in Tennessee. Snail darters may also occur in the
Alabama portion of the Elk River over more than 20 river miles of free-
flowing stream down to the portion of the river inundated by Wheeler
Reservoir (Simmons 2019, supplementary data; Shollenberger 2019, pp.
14-16).
Our assessment of the tributary populations of the snail darter
supports the determination that Alternative B has been met based on the
establishment of the French Broad River population that is comparable
to the Hiwassee population. Additionally, the Ocoee River, Bear Creek,
and Elk River populations are comparable to the Big Sewee Creek
historical population, which was found across 4.2 miles of stream,
exceeding the prescription in Alternative B for at least one additional
large population or two additional small populations.
The intent of Alternative C has been fulfilled because the
documented conditions are functionally equivalent to those prescribed.
This alternative of the recovery criteria calls for the maintenance of
viable populations in five separate streams. The definition for viable
populations in the 1983 recovery plan requires biannual monitoring over
a 10-year period with enough data to demonstrate a stable or increasing
population size and evidence of reproduction indicated by the presence
of at least two year classes present in each year sampled. The best
available monitoring data do not allow us to determine whether
populations meet this definition, because most of our collections come
from TVA IBI surveys that are not species-specific. However, our
analysis of the tributary populations found 10 populations that were
considered at least moderately resilient (see table 1 in Summary of
Biological Status, below), which we conclude is equivalent to a
determination that the populations are viable. Of these, nine met the
requirement of Alternative C that at least two year classes be present.
The discovery of populations in Bear Creek, Elk River, Wheeler
Reservoir, and Pickwick Reservoir since 2009 shows evidence of either
species expansion or growth of existing populations to the level of
detection (see table 2 in Summary of Biological Status, below). The
presence of resilient populations in 10 tributaries and 7 mainstem
reservoirs across four physiographic regions provides evidence of high
redundancy and representation for the species (see further explanation
of these terms in Analytical Framework, below).
In summary, alternative pathways to recovery A and B have been met
or exceeded, and the intent of alternative C has been fulfilled. The
recovery plan only required one of the three alternative pathways to be
met. Therefore, we conclude that the recovery criteria established by
the plan have been surpassed.
Regulatory and Analytical Framework
Regulatory Framework
Section 4 of the Act (16 U.S.C. 1533) and its implementing
regulations in title 50 of the Code of Federal Regulations 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 threatened
and endangered species. In 2019, jointly with the National Marine
Fisheries Service, the Service issued final rules that revised the
regulations in 50 CFR parts 17 and 424 regarding how we add, remove,
and reclassify threatened and endangered species and the criteria for
designating listed species' critical habitat (84 FR 45020 and 84 FR
44752; August 27, 2019). At the same time 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
(collectively, the 2019 regulations).
However, on July 5, 2022, the U.S. District Court for the Northern
District of California vacated the 2019 regulations (Center for
Biological Diversity v. Haaland, No. 4:19-cv-05206-JST, Doc. 168 (N.D.
Cal. July 5, 2022) (CBD v. Haaland)), reinstating the regulations that
were in effect before the effective date of the 2019 regulations as the
law governing species classification and critical-habitat decisions.
Accordingly, in developing the analysis contained in this final rule,
we applied the pre-2019 regulations, which may be reviewed in the 2018
edition of the Code of Federal Regulations at 50 CFR 17.31, 17.71,
424.02, 424.11(d) and (e), and 424.12(a)(1) and (b)(2). Because of the
ongoing litigation regarding the court's vacatur of the 2019
regulations,
[[Page 60304]]
and the resulting uncertainty surrounding the legal status of the
regulations, we also undertook an analysis of whether the final rule
would be different if we were to apply the 2019 regulations. That
analysis, which we described in a separate memo in the decisional file
and posted on <a href="https://www.regulations.gov">https://www.regulations.gov</a>, concluded that we would have
reached the same decision if we had applied the 2019 regulations. This
is because both before and after the 2019 regulations, the standard for
whether a species warrants delisting has been, and will continue to be,
whether the species meets the definition of an endangered species or a
threatened species. Further, we concluded that our determination of the
foreseeable future would be the same under the 2019 regulations as
under the pre-2019 regulations.
On September 21, 2022, the U.S. Circuit Court of Appeals for the
Ninth Circuit stayed the district court's July 5, 2022, order vacating
the 2019 regulations until a pending motion for reconsideration before
the district court is resolved (In re: Cattlemen's Ass'n, No. 22-
70194). The effect of the stay is that the 2019 regulations are the
governing law. Because of our desire to remove regulatory burdens in a
timely manner whenever species no longer meet the definition of an
endangered or threatened species, rather than revise the proposal in
response to the Ninth Circuit's decision for submission of a final rule
to the Federal Register, we hereby adopt the analysis in the separate
memo that applied the 2019 regulations as our primary justification for
the final rule. However, due to the continued uncertainty resulting
from the ongoing litigation, we also retain the analysis in this
preamble that applies the pre-2019 regulations and we conclude that,
for the reasons stated in our separate memo analyzing the 2019
regulations, this final rule would have been the same if we had applied
the 2019 regulations.
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. The determination to delist a
species must be based on an analysis of the same five factors.
We use the term ``threat'' to refer in general to actions or
conditions that are known to or are reasonably likely to negatively
affect individuals of a species. The term ``threat'' includes actions
or conditions that have a direct impact on individuals (direct
impacts), as well as those that affect individuals through alteration
of their habitat or required resources (stressors). The term ``threat''
may encompass--either together or separately--the source of the action
or condition or the action or condition itself.
However, the mere identification of any threat(s) does not
necessarily mean that the species meets the statutory definition of an
``endangered species'' or a ``threatened species.'' In determining
whether a species meets either definition, we must evaluate all
identified threats by considering the species' expected response and
the effects of the threats--in light of those actions and conditions
that will ameliorate the threats--on an individual, population, and
species level. We evaluate each threat and its expected effects on the
species, then analyze the cumulative effect of all of the threats on
the species as a whole. We also consider the cumulative effect of the
threats in light of those actions and conditions that will have
positive effects on the species--such as any existing regulatory
mechanisms or conservation efforts. The Secretary determines whether
the species meets the definition of an ``endangered species'' or a
``threatened species'' only after conducting this cumulative analysis
and describing the expected effect on the species now and in the
foreseeable future.
The Act does not define the term ``foreseeable future,'' which
appears in the statutory definition of ``threatened species.'' Because
the decision in CBD v. Haaland vacated our 2019 regulations regarding
the foreseeable future, we refer to a 2009 Department of the Interior
Solicitor's opinion entitled ``The Meaning of `Foreseeable Future' in
Section 3(20) of the Endangered Species Act'' (M-37021). That
Solicitor's opinion states that the foreseeable future ``must be rooted
in the best available data that allow predictions into the future'' and
extends as far as those predictions are ``sufficiently reliable to
provide a reasonable degree of confidence in the prediction, in light
of the conservation purposes of the Act.'' Id. at 13.
It is not always possible or necessary to define 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' 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
To assess species viability, we use the three conservation biology
principles of resiliency, redundancy, and representation (Shaffer and
Stein 2000, pp. 306-310). Briefly, resiliency supports the ability of
the species to withstand environmental and demographic stochasticity
(for example, wet or dry, warm or cold years), redundancy supports the
ability of the species to withstand catastrophic events (for example,
droughts, large pollution events), and representation supports the
ability of the species to adapt over time to long-term changes in the
environment (for example, climate change). In general, the more
resilient and redundant a species is and the more representation it
has, the more likely it is to sustain populations over time, even under
changing environmental conditions. 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.
Summary of Biological Status
Resiliency Analysis
As explained above in Evaluating Populations, the existing data
available do not allow us to estimate population sizes for snail
darter. However,
[[Page 60305]]
collections over multiple years and the presence of multiple age
classes provide evidence of persistence in tributaries throughout the
snail darter's range. In the reservoirs, the capture of multiple
individuals and evidence of multiple age classes typically represents a
sustainable population. Where available, presence of snail darters in
breeding condition is used as additional evidence of spawning, because
snail darters move onto the spawning ground before spawning commences
(Starnes 1977, p. 64). We used IBI scores from fixed monitoring
stations to address stream health where possible for tributary
populations. These scores are generated from fish assemblage surveys
throughout the Tennessee River Valley that rank streams from 12 to 60
(poor to excellent) based on metrics such as total number of species,
proportions of intolerant and tolerant species, and the numbers of
species in various ecological guilds (TVA 2005, pp. 5-7). We use these
measures to describe the resiliency of the snail darter populations and
their contributions to the species' recovery.
Tributary Resiliency--We characterized snail darter population
resiliency in 14 tributaries (11 extant populations, one extirpated,
and two apparently not established with only one collection each and no
evidence of reproduction) using data related to three factors:
collections in multiple years since 2009, presence of multiple year
classes in these samples, and TVA IBI scores for the tributary
populations (see resiliency scores for these factors in table 1,
below). Detection of the species in multiple years provides evidence of
persistence within a tributary. Consistent collections also indicate
population numbers that are high enough to be detected using non-
depletion methods (not every fish in a sample reach is caught), which
is relevant for species like the snail darter that are difficult to
capture with standard fish sampling equipment. The presence of multiple
age classes is evidence of successful reproduction in the population.
Given that snail darters only live 4 years and likely do not mature
until their second year, it would only take a few years of failed
reproduction for a population to be extirpated (Etnier and Starnes
1993, p. 588). We reviewed the available data to determine population
scores for each of the tributaries. The best available data are not
sufficient to determine snail darter population size or trends due to
the typically small numbers collected at any given site; however, we
can address resiliency of the tributary populations by looking at
persistence over time and evidence of reproduction. To do this, we used
data from snail darter collections and observations from TVA and
Conservation Fisheries, Inc., and data compiled by the Tennessee
Aquarium Conservation Institute.
We used IBI scores to address stream community health where
possible for tributary populations. Measuring the overall fish
community is a way to investigate habitat quality, water quality, and
ecosystem stability by proxy of the fish that live in the stream. The
IBI incorporates 12 metrics to measure fish community health based on
the number of species or proportion of individuals in different guilds
(group of species with similar life history) compared to what is
expected in a reference condition stream. These metrics are adjusted
based on stream size and physiographic region in order to be relevant
to the differences in natural conditions across the Tennessee River
Basin. Each metric is assigned a value matching a ranking of good (5),
fair (3), or poor (1). The 12 metrics are then summed for each,
yielding an overall rating of the stream community health. An IBI score
of 12 to 22 equates to a very poor rating, 28 to 34 to a poor rating,
40 to 44 to a fair rating, 48 to 52 to a good rating, and 58 to 60 to
an excellent rating. Scores between these ranges received intermediate
ratings (TVA 2005, entire). To determine potential IBI trends, we
compared overall IBI scores for sites within the range of snail darters
in each tributary from 2009 to 2019. Roughly half of the tributaries
(French Broad River, Little River, Hiwassee River, Ocoee River, Elk
River, and Flint River) showed some improvement during the 1999-2009
period, but during the 2009-2019 analysis period, the communities in
all of the tributaries were mostly stable.
We combined the population metrics to give a population score (low,
medium, or high), and the habitat metrics combined to form a composite
habitat score (low, medium, or high). These scores are compiled in
table 1, below. The population and habitat scores were averaged to
provide the overall resilience score. Tributaries with multiple
collections (of several fish each collection) and multiple age classes
over the 12-year period were ranked high; conversely, those with only
one collection and no evidence of reproduction were considered not
established. Age classes were assigned by body length, based on life-
history studies (Starnes 1977, pp. 47-63; Hickman and Fitz 1978, pp.
10-19). Sites with multiple collections but only one age class were
ranked low. Tributaries with good or better IBI scores that were stable
or improving were then ranked high, and tributaries with fair IBI
scores with stable or improving conditions were ranked moderate.
Overall resilience was calculated by averaging the column scores. Where
snail darters had been extirpated or not established, IBI scores were
not incorporated. While the habitat in Little River is very good, we
found that the low numbers (three or fewer individuals in any single
observation) of snail darters captured and the lack of multiple age
classes did not warrant categorizing the Little River population as
moderate or high. Our results of the tributary resiliency analysis are
summarized in table 1.
Table 1--Tributary Population Resiliency Based on Collection Data and TVA IBI Scores From 2009-2019
--------------------------------------------------------------------------------------------------------------------------------------------------------
Multiple Multiple age Overall
Tributary detections classes Population score IBI score IBI trend Habitat score resiliency
--------------------------------------------------------------------------------------------------------------------------------------------------------
Holston River................ Yes............. Yes............. High............ Fair............ Stable......... Moderate....... Moderate/high.
French Broad River........... Yes............. Yes............. High............ Fair/good....... Stable or High........... High.
improving.
Little River................. Yes............. No.............. Low............. Good/excellent.. Stable......... High........... Low.
Citico Creek................. No.............. No.............. Not established. Good............ Stable......... High........... Not
established.
Big Sewee Creek.............. No.............. No.............. Extirpated...... Poor/fair....... Stable......... Low............ Extirpated.
Hiawassee River.............. Yes............. Yes............. High............ Good/excellent.. Stable......... High........... High.
Ocoee River.................. Yes............. Yes............. High............ Fair............ Stable......... Moderate....... Moderate/high.
South Chickamauga Creek...... Yes............. Yes............. High............ Fair............ Stable or Moderate....... Moderate/high.
declining.
Sequatchie River............. Yes............. Yes............. High............ Fair............ Stable or Moderate....... Moderate/high.
declining.
Paint Rock River............. Yes............. Yes............. High............ Fair/good....... Stable......... High........... High.
Flint River.................. No.............. No.............. Not established. Fair............ Insufficient Moderate....... Not
data. established.
Elk River.................... Yes............. Yes............. High............ Fair/good....... Stable or High........... High.
improving.
Shoal Creek.................. No.............. No.............. Not established. Good............ Stable or High........... Not
improving. established.
[[Page 60306]]
Bear Creek................... Yes............. Yes............. High............ Good............ Stable or High........... High.
improving.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Reservoir Resiliency--Using the data available from the TVA snail
darter trawl surveys (Simmons 2019, p. 3), we analyzed resiliency of
the reservoir populations based first on the number of individuals
captured and second, evidence of reproduction with evidence of
reproduction established either through presence of multiple age
classes, adults in spawning condition (gravid females and/or males
flowing milt [sperm]), or juveniles. To categorize number of
individuals, we classified collections of 0-4 individuals as low, 5-9
as moderate, and 10 or more as high. To classify reproduction, given
the limited sampling effort to date, collection of more than one age
class or other evidence of reproduction resulted in a high rating in
the reproduction metrics. Collection of only one age class or no other
evidence of reproduction resulted in a low rating. Similar to the
stream population, overall resilience was calculated by averaging the
scores of the number collected and reproduction metrics. Results are
summarized below in table 2.
Table 2--Reservoir Population Collections Based on TVA Benthic Trawls, 2016-2019 *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Population score (number Age
Reservoir collected) classes Evidence of reproduction Reproduction score Overall resilience
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fort Loudoun........................ Low (2).................. 2 No....................... High..................... Moderate.
Watts Bar........................... Low (3).................. 1 Yes...................... High..................... Moderate.
Chickamauga......................... Low (4).................. 2 Yes...................... High..................... Moderate.
Nickajack........................... High (11)................ 2 Yes...................... High..................... High.
Guntersville........................ High (33)................ 2 No....................... High..................... High.
Wheeler............................. High (18)................ 2 Yes...................... High..................... High.
Wilson.............................. Low (0).................. 0 No....................... N/A...................... Not established.
Pickwick............................ High (18)................ 3 No....................... High..................... High.
Kentucky............................ Low (0).................. 0 No....................... N/A...................... Not established.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Age classes based on total length measurements from Hickman and Fritz (1978). Evidence of reproduction is based on capture of juvenile individuals,
adults in spawning condition, or multiple age classes (Simmons 2019, p. 7).
For the purpose of evaluating the snail darter's status, we
considered those tributaries that ranked moderate or high as
contributing to resiliency. Because of the limited amount of reservoir
sampling that has been completed, we considered those reservoir
populations that had evidence of reproduction present as permanent,
independent populations (Simmons 2019, p. 2) that contribute to
resiliency. We, therefore, considered 7 reservoir populations (Fort
Loudoun, Watts Bar, Chickamauga, Nickajack, Guntersville, Wheeler, and
Pickwick) and 10 tributary populations (Holston, French Broad, Little,
Hiwassee, Ocoee, Sequatchie, Paint Rock, and Elk Rivers, and South
Chickamauga and Bear Creeks) as contributing to species resiliency. We
did not count Wilson Reservoir or Kentucky Reservoir toward resiliency
because snail darters had never been collected there despite trawling
efforts. While Watts Bar is only represented by three juveniles, their
collection far from any large tributaries is evidence of reproduction
within the reservoir. We did not consider Citico Creek, Big Sewee
Creek, Flint River, or Shoal Creek as contributing toward resiliency
either because the species had not been collected there within the
analysis period despite multiple efforts (Big Sewee Creek, Citico
Creek) or because a single snail darter had been found on only one
occasion (Shoal Creek, Flint River); therefore, we considered the
populations to be not established in those locations (see table 1,
above).
Analysis of Redundancy and Representation
With discoveries of new tributary and reservoir populations, the
known redundancy and representation of the snail darter has expanded
during the analysis period. When we listed the species (40 FR 47505;
October 9, 1975), it had very low redundancy and representation because
only one population was known from several miles of the Little
Tennessee River, in the Ridge and Valley physiographic region.
Currently, the species is known across more than 400 miles (640 km) of
the Tennessee River Valley, with moderately to highly resilient
populations in 9 tributaries and 7 reservoirs, providing a level of
redundancy that helps shield the species from localized stochastic
events.
While we do not have population genetic data for the snail darter,
we can look at the species' ability to adapt to changes in the
environment (representation) by looking at its distribution across a
range of habitats and physiographic regions. Resilient populations are
currently known from streams ranging in size from mid-sized creeks to
the large Tennessee River itself, with collections in depths ranging
from less than 3 ft (1 m) to 25 ft (7.6 m). These populations occur in
reservoirs and tributaries with these conditions in four different
physiographic regions (Ridge and Valley, Cumberland Plateau, Highland
Rim, and Gulf Coastal Plain). This wide range of habitat use and
geographic distribution helps to demonstrate the snail darter's
adaptability to changing environmental pressures (representation).
Summary of Factors Affecting the Species
A recovered species is one that no longer meets the Act's
definition of an endangered species or a threatened species.
Determining whether the status of a species has improved to the point
that it can be delisted or downlisted
[[Page 60307]]
requires consideration of the same five factors identified above for
listing a species. When we initially listed the snail darter as
endangered in 1975, the only identified threat influencing its status
was the modification and loss of habitat and curtailment of range
(Factor A) caused by the completion of Tellico Dam and the flooding of
the entire known range of the species. When we reclassified the species
as threatened in 1984, we evaluated a more complete list of factors
based on improved knowledge of the snail darter's range and life
history. These factors included threats to habitat such as shipping
activities in the mainstem Tennessee River, impacts from development in
some of the tributaries such as South Chickamauga Creek, threats from
agricultural runoff and channelization in streams like the Elk River,
impacts from coal mining in the Sequatchie River watershed, and
chemical spills in the Hiwassee and Ocoee watersheds (Factor A);
excessive collection associated with the notoriety of the species
(Factor B); and protections afforded the species by State and Federal
laws (Factor D). The following analysis evaluates these previously
identified threats, any other threats currently facing the species that
we have identified, as well as any other threats that are reasonably
likely to affect the species in the foreseeable future.
To establish the foreseeable future for the purpose of evaluating
trends in the threats and the species' responses, we analyzed trends
from historical data on distribution and abundance, ongoing
conservation efforts, factors currently affecting the species, and
predictions of future climate change. When combined with our knowledge
of factors affecting the species (see discussion below), available data
allow us to reasonably predict future conditions, albeit with
diminishing precision over time. Given our understanding of the best
available data, for the purposes of this rule, we consider the
foreseeable future for the snail darter to be approximately 30 years.
We determined that we can reasonably predict the threats to the species
and the species' response during this timeframe based on climate
vulnerability assessments through 2050, the planning horizon of the
reservoir release improvement program (RRIP), and enough time for the
species to respond based on biology and lifespan.
As noted above, when the species was reclassified from endangered
to threatened (49 FR 27510; July 5, 1984), the reclassification rule
identified additional threats to habitat in the additional populations
established or discovered since the original listing (40 FR 47505;
October 9, 1975). These included threats from shipping activities in
the mainstem Tennessee River, impacts from development in some of the
tributaries such as South Chickamauga Creek, threats from agricultural
runoff and channelization in streams like the Elk River, impacts from
coal mining in the Sequatchie River watershed, and chemical spills in
the Hiwassee and Ocoee watersheds.
One of the biggest factors still affecting the snail darter is the
impoundment of large portions of the Tennessee River Valley. TVA
operates 9 dams on the mainstem Tennessee River and 38 dams on
tributaries to the Tennessee River. These impoundments create large
areas of deep, still water that do not meet the habitat needs of the
snail darter. Snail darters are limited in the depth they can occupy by
the presence of food resources. Snails, the darter's preferred prey,
live only in water shallow enough for light to penetrate and allow
algae to grow on the substrate, about 15-20 ft (5-7 m) in much of the
Tennessee mainstem. Impoundment also reduces stream flow and allows
fine sediments to settle out, which can cover the clean gravel habitats
needed by snail darters. Additionally, these dams were initially
operated with a hydropeaking strategy, only releasing water when needed
to generate electricity or maintain reservoir level or flood storage
capacity. In addition, many of these releases came from the water
levels within the reservoir that held cold, oxygen-deficient water.
Collectively, these factors created conditions in the tailwaters that
negatively affected water quality, food availability, and fish
diversity.
Given the long operational lifespan of dams (more than 100 years),
it is nearly certain that the TVA reservoirs will be in place for the
foreseeable future. However, beginning in 1981, TVA began studies to
improve conditions in the tailwaters of their dams. The cold, oxygen-
deficient water released from the bottom of many of the dams created
conditions that eliminated many fish and mussel species from these
areas. Through the RRIP, TVA began implementing strategies to increase
minimum flow, dissolved oxygen, and, in some cases, temperature, in the
tailwaters of their dams beginning in 1991 (Bednarek and Hart 2005, p.
997). In 2002, TVA conducted a reservoir operation study to consider
how to implement these changes across the basin to improve the health
of the river (TVA 2004, p. ES-3). The result was to manage the river
based on minimum flows instead of reservoir level and improve tailwater
conditions. These changes have resulted in significant improvements in
biological and abiotic variables and increases in fish and invertebrate
diversity in many TVA dam tailwaters (Layzer and Scott 2006, entire;
Bednarek and Hart 2005, entire; Scott et al. 1996, entire). These
improvements have likely resulted in improved conditions for the snail
darter and may have contributed to improvements to the species' status
within tailwaters since the 1990s, across more than 400 miles (640 km)
of the mainstem of the Tennessee River. Since the RRIP is based on
ecologically meaningful parameters in the tailwaters, such as dissolved
oxygen and temperature, this program may be able to provide some
resiliency to a warming climate and precipitation variability in the
future, especially if TVA adjusts the program to maintain the needed
conditions in the tailwaters. The reservoir operation study is planned
along an approximately 25-year timeline, extending to 2030 (TVA 2004,
p. ES-4). However, given the presence of at least 10 other listed
aquatic species in the tailwaters of the mainstem Tennessee River
reservoirs and the complexities of changing the operations plan, it is
highly likely that TVA will continue RRIP as part of its compliance
with the Act for these other species beyond the timeline of the
environmental impact statement (EIS) and biological opinion that were
prepared under section 7 of the Act before alterations were made to dam
release management. For these same reasons, TVA will likely incorporate
RRIP to protect federally listed mussels when it revisits its EIS
around 2030, and because the current EIS's term is 25 years, it is
reasonable to assume TVA will issue another 25-year EIS. Therefore, we
anticipate that the conditions benefiting the snail darter will
continue through at least midcentury (Baxter 2020, pers. comm.).
Overall, the persistence and expansion of snail darter populations in
the mainstem since the 1970s indicate greater resiliency in these
habitats than was considered at the time of listing, particularly now
with the implementation of TVA's RRIP.
Anthropogenic changes to the land can also negatively impact the
snail darter and its habitats. Sedimentation is one of the biggest
threats to water quality in the Tennessee River Valley, including in
streams occupied by snail darters. Big Sewee Creek has been impacted by
sedimentation from persistent farming in the watershed, reducing the
amount and quality of
[[Page 60308]]
gravel habitat in the stream. The predominant agricultural activities
contributing to sedimentation in Big Sewee Creek (livestock pasture and
row crops) are exempt from many State and Federal regulations designed
to reduce sediment runoff, and these activities are likely to continue
into the future. Therefore, we do not expect this population to
reestablish unless habitat conditions improve in the future.
Sedimentation from agriculture and development is also considered a
concern in the lower Little Tennessee River, Sequatchie River, South
Chickamauga Creek, and Paint Rock River watersheds. Watershed-level
efforts have been conducted to address sedimentation issues in some of
the tributaries where snail darters have been found. The South
Chickamauga Creek Land Treatment Watershed Project, an effort of the
Natural Resources Conservation Service of the U.S. Department of
Agriculture (USDA), began in 2001, to reduce the runoff of sediment and
nutrients in the watershed by installing animal waste management
systems (see 65 FR 44519; July 18, 2000). Additionally, the Limestone
Valley Resource Conservation and Development Council is working with a
wide variety of partners to implement the South Chickamauga Creek
Headwaters Management Plan, developed in 2012, to address water quality
issues (Smith and Huser 2012, pp. i-3). In the Paint Rock River, The
Nature Conservancy designated a ``landscape conservation area'' and
worked to address sedimentation issues from agriculture throughout the
watershed, resulting in improved conditions for aquatic fauna
(Throneberry 2019, unpublished data). Many of these efforts include
restoring natural stream channel characteristics where streams have
been channelized. These efforts have been undertaken outside of
species-specific recovery efforts for the snail darter, and they are
likely to continue regardless of the delisting of the species. Other
small-scale efforts have been undertaken to reduce sedimentation in
many of the other tributaries inhabited by snail darters. It is likely
that sedimentation has resulted in the extirpation of snail darters
from Big Sewee Creek, but there is some potential for recolonization by
individuals from Chickamauga Reservoir if habitat conditions improve.
Urban and suburban development may impact the snail darter as well.
Increases in the amount of impervious surfaces associated with
development increase runoff to streams, destabilize hydrology, and
increase water temperature. Additionally, residential and commercial
development are associated with increased runoff of lawn and automotive
chemicals into the streams (Matthaei and Lang 2016, p. 180; Walsh et
al. 2005, p. 707). The snail darter tributaries currently most impacted
by development and the associated chemical and sediment runoff are
South Chickamauga Creek in Chattanooga, Tennessee; Flint River in
Huntsville, Alabama; and Little River in Maryville, Tennessee. Based on
the SLEUTH (Slope, Land use, Excluded area, Urban area, Transportation,
Hillside area) model, these areas are anticipated to have increased
suburban and urban growth in the next 30 years, which might further
impact South Chickamauga Creek, Flint River, and Little River; there is
also the potential for increased urban impacts to the Sequatchie River
and Paint Rock River watersheds associated with the growth of
Chattanooga and suburban development from Huntsville, respectively
(Terando et al. 2014, pp. 1-3). However, based on the moderate
resilience of snail darters in South Chickamauga Creek (see table 1,
above), some evidence supports a conclusion that the species is
resilient to the impacts of urbanization.
Additionally, the Thrive Regional Partnership is a group working to
promote responsible growth in a 16-county region in the Greater
Chattanooga area. The partnership's goal is to improve communities
while maintaining healthy ecosystems. Thrive has identified portions of
streams and surrounding land that are key to preserving and enhancing
water quality in the region of interest, with the goals of conserving
50 percent of unprotected forest and improving water quality in at
least 50 percent of polluted streams by 2055. The area covered by this
initiative includes portions of the Big Sewee Creek, South Chickamauga
Creek, Sequatchie River, and Paint Rock River watersheds (Thrive
Regional Partnership 2019, entire).
The threat of chemical and industrial spills was raised as a
potential threat in the downlisting rule (49 FR 27510; July 5, 1984).
The range of the snail darter is crossed by several major highways and
railroad lines, making the possibility of a spill during transport an
ongoing risk. Such spills have occurred as recently as 1991 in the
Hiwassee River. While spills may have severe impacts locally, they are
unlikely to affect the species as a whole given its wide range in the
mainstem of the Tennessee River and several tributaries (Service 2013,
p. 18). Furthermore, the Ocoee River has suffered from industrial and
mine runoff from the historical copper extraction in the watershed.
Within the Ocoee River watershed, concerted efforts have been made to
clean up industrial and mine-related pollution, resulting in much
improved water quality and a healthier ecosystem which may have
contributed to the increased numbers of snail darters seen in that
river since the Service's 2013 5-year review (Service 2013, p. 12;
Simmons 2019, unpublished data).
The threat to snail darters from coal mining in the Sequatchie
Valley has been greatly reduced since the recovery plan was completed.
Mining for coal in the Sequatchie Valley ceased in the 1990s, and since
that time, there have been efforts to remediate acid mine drainage in
the area. Currently, there are no active coal mining permits in the
Sequatchie Valley (Office of Surface Mining Reclamation and Enforcement
(OSMRE) 2016, p. 34; Interstate Technology & Regulatory Council (ITRC)
2010, entire).
The Tennessee River is a major inland shipping corridor, and in the
downlisting rule (49 FR 27510; July 5, 1984), activities associated
with barge traffic were considered to potentially threaten snail
darters through habitat alterations in the mainstem Tennessee River
reservoirs. Barge and large boat wakes can result in significant bank
erosion along the river. Within the mainstem reservoirs, bank
stabilization efforts have occurred in some significantly impacted
areas and reduced sedimentation at those locations, but there is no
concerted plan to address this source of sediment across the Tennessee
River Basin. However, there is some evidence that areas of consistent
traffic, such as barge mooring cells, may provide areas of silt-free
habitat swept clean by tug engines (Matthews 2017, pers. comm.; Walker
and Alford 2016, p. 1101).
In summary, while effects to snail darter habitat (Factor A)
associated with continued urbanization and agriculture are certain to
persist into the foreseeable future, efforts are being made to reduce
the impact to many of the tributaries inhabited by snail darters.
Additionally, snail darters appear to be resilient to current levels of
urbanization and agriculture, including practices such as
channelization, in certain tributaries such as South Chickamauga Creek
and Sequatchie River. In the Sequatchie River, the threat from coal
mining is reduced with the cessation of mining in the valley and
ongoing reclamation efforts. The mainstem populations are less
susceptible to sedimentation and runoff associated with agriculture and
urbanization due to the buffering
[[Page 60309]]
capacity of the larger river, but they still may be affected by bank
erosion and industrial transport along the Tennessee River. However,
population stability and apparent expansion in the mainstem since the
1970s demonstrate the resiliency of the snail darter within these
habitats, especially with the implementation of TVA's RRIP.
At the time of the downlisting rule (49 FR 27510; July 5, 1984),
the Service projected that the notoriety of the snail darter could
result in an increase in illegal collection (Factor B); however, no
such activities have been observed or documented since that rule was
published. Snail darters receive some protection against collection
from the States. The species is listed as threatened in Tennessee,
endangered in Georgia, and protected as a non-game species in Alabama
and Mississippi. These protections require State permits for the
collection of the species.
The snail darter's habitat is also protected by State water quality
laws that require the use of best management practices, such as leaving
a riparian buffer, when clearing or building near a stream (Factor D).
In Tennessee, any waterway with a State-listed species is designated an
``Exceptional Tennessee Waterway,'' and projects impacting these
streams are required to undergo additional review before receiving the
necessary State permits. While agriculture is typically exempt from
many of the provisions in State laws, various efforts described above,
such as those in the Paint Rock River and South Chickamauga Creek, are
working to reduce the impact of sedimentation from agriculture on the
snail darter. Additionally, the snail darter's range overlaps with the
ranges of more than 10 federally endangered mussels. This provides some
protection, as entities implementing projects with a Federal nexus,
such as infrastructure repair and construction and dam operation, are
required to consult with the Service to reduce the impacts to listed
species and designated critical habitat. These consultations may result
in changes to the project to reduce sedimentation or limit the time of
year when construction can take place to reduce disruption to the life
history of a species. The protection, restoration, conservation, and
management of ecological resources within the snail darter's range have
been broadly enhanced through Executive orders and Federal regulations
since the species was listed. These include provisions emphasizing the
protection and restoration of ecosystem function and quality in
compliance with existing Federal environmental statutes and regulations
(e.g., National Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.)
and Clean Water Act (CWA; 33 U.S.C. 1251 et seq.)) and endorsing
Federal efforts to advance environmental goals. Recent water resources
authorizations have also enhanced opportunities for the involvement of
the U.S. Army Corps of Engineers and other Federal agencies in studies
and projects to specifically address objectives related to the
restoration of ecological resources (e.g., section 1135 of the Water
Resources Development Act of 1986, as amended, 33 U.S.C. 2201 et seq.).
Protections associated with the CWA and State wildlife laws will
continue to provide some protection to the snail darter. The fear that
the species' notoriety would result in increased collection or other
forms of take has not been realized since we reclassified the species
to threatened, and collection is unlikely to have a major impact on
species resilience in the foreseeable future. Additionally, even if
range States were to cease protecting the snail darter, its wide range
and current redundancy should minimize its risk of extinction for the
foreseeable future.
In addition to the threats mentioned in the downlisting rule (49 FR
27510; July 5, 1984) that are addressed above, we now consider other
threats or stressors that reasonably could affect the snail darter in
the foreseeable future. One such potential threat is climate change. In
the southeastern United States, clear trends in climate predictions are
limited. However, annual temperatures are projected to increase; cold
days will become less frequent; the freeze-free season will lengthen by
up to a month; temperatures exceeding 95 degrees Fahrenheit ([deg]F)
(35 degrees Celsius ([deg]C)) will increase; heat waves will become
longer; and the number of category 5 hurricanes will increase (Ingram
et al. 2013, p. 32). Variability in weather is predicted to increase,
resulting in more frequent and more extreme dry years and wet years
over the next century, with limited evidence of a directional
precipitation trend anticipated in the Tennessee River Valley
(Mulholland et al. 1997, pp. 951-955; Ingram et al. 2013, pp. 15, 35).
One study (Jones et al. 2015, entire) did find a small, statistically
significant negative trend indicating precipitation had decreased
between 1950 and 2009 in a parts of the Upper Tennessee River Valley,
but overall the trends during this time period were mixed.
There is some evidence that the increased variability may already
be taking effect. The two wettest years on record for the Tennessee
River Valley (Simmons 2020, unpublished data) are 2018 and 2019. During
the late summer and early fall of 2019, the second wettest year
overall, parts of the Valley temporarily experienced abnormally dry or
drought conditions (USDA Drought Monitor for Tennessee River Valley,
October 1, 2019).
Increased rainfall will result in increased runoff, higher river
levels, and longer periods of spilling from the top of dams by TVA.
During periods of spilling at dams, there is the chance for more
oxygenation of tailwaters and temperature mixing that could benefit the
snail darter. However, increased rainfall, especially extreme events,
would increase runoff of sediment and pollutants into tributaries and
eventually into the mainstem. These inputs could potentially degrade
spawning and foraging habitat for the snail darter. Increased flows
during the spawning season could also increase the distance that the
pelagic larvae of snail darters drift before becoming benthic. If the
larvae found suitable habitat, increased flow could expand the range of
the species and contribute to genetic mixing; however, there is also
the chance that larvae could be pushed into unsuitable habitat which
would result in reduced survival. Drought would most likely impact the
shallower habitats inhabited by snail darters in tributaries. The area
of shoal habitat available during periods of low flow could be reduced
during a drought. The flows could be further reduced by water
extraction for irrigation. These reductions of spawning habitat could
result in lower spawning success. If discharge is reduced enough, the
clean-swept gravel habitats that the snail darter relies on in the
mainstem could begin to retain silt, reducing habitat quality.
There is evidence that the habitat and life history of the snail
darter will protect it from predicted changes in climate over the next
30 years. In a 2017 climate change vulnerability assessment of 700
species, the Appalachian Landscape Conservation Cooperative (LCC)
ranked the snail darter as ``presumed stable'' through 2050 under
predicted climate conditions (Appalachian LCC 2017, supplemental data).
Being adapted to large river habitats, the snail darter is less
susceptible to impacts from high-flow events. As much of its habitat in
the mainstem is already impounded, the effects of high water are less
meaningful, and TVA flood control efforts may offset some of the strong
flow peaks associated with extreme rain events. The species' preference
for deeper water habitats and late winter spawning period protects it
from
[[Page 60310]]
drought. Deep water habitats are not impacted by droughts as
drastically as shallow habitats. The RRIP in TVA tailwaters ensures
availability of suitable water for the mainstem populations throughout
the year despite the occurrence of drought. Drought is also unlikely to
impact spawning events on shoals in tributaries because late winter and
early spring are typically the wettest times of the year within the
Tennessee River Valley. The snail darter is likely also protected from
the projected temperature increases by adaptation to larger streams and
the thermal buffering of the large reservoirs on the mainstem.
If we examine current projections beyond our 30-year foreseeable
future, under plausible future greenhouse gas concentrations termed
representative concentration pathways (RCP), warming temperatures and
precipitation projections continue to suggest mixed effects to the
species. Relative to 1981-2010, over 2050-2074, the 50th percentile
(median) for the Tennessee Region, maximum air temperature warms by 4.4
[deg]F (2.4 [deg]C) in RCP 4.5, whereas the region warms by 6.4 [deg]F
(3.6 [deg]C) in RCP 8.5 (Alder and Hostetler 2013, entire). Changes in
precipitation are not as apparent. Relative to 1981-2010, over 2050-
2074, the 50th percentile (median) for the Tennessee Region,
precipitation increases by only 0.2 in (5.1 mm) per month in both RCP
4.5 and RCP 8.5 (Alder and Hostetler 2013, entire). We still consider
2050 as the foreseeable future timeline for this species because the
time frame associated with the RRIP and other stressors have the
greatest predictability between now and 2050, which allows us to draw
stronger conclusions regarding the species response and condition.
Additionally, we have greater certainty about the snail darters'
response to changing climactic conditions between now and 2050 because
we have both the projections and scientific sources that predict the
species' response, such as the LCC report. Further, the climate
projections are more reliable between now and 2050 as compared to
beyond 2050 because the models diverge significantly after 2050, which
results in substantial uncertainty regarding how changes in climate
will manifest late-century. As a result, we do not consider the snail
darter to be vulnerable to the effects of climate change in the
foreseeable future.
The increases documented in the abundance and distribution of the
snail darter since it was listed in 1975 have led to a better
understanding of the current and future condition of the species'
resiliency, redundancy, and representation across the range. The
observed variations in population size, density, or distribution of the
snail darter are typical of metapopulation dynamics. Surveys have shown
that individual populations may decline based on localized stressors
(e.g., severe sedimentation, toxic spills, streamflow alteration) or
their cumulative effects. When threats occur together, one may
exacerbate the effects of another, causing effects not accounted for
when threats are analyzed individually. However, the best available
information does not demonstrate that cumulative effects are occurring
at a level sufficient to negatively affect the species now nor do we
anticipate that they will in the future.
Summary of Comments and Recommendations
In the proposed rule published in the Federal Register on September
1, 2021 (86 FR 48953), we requested that all interested parties submit
written comments on our proposal to delist the snail darter by November
1, 2021. We also contacted appropriate Federal and State agencies,
scientific experts and organizations, and other interested parties and
invited them to comment on the proposal. We did not receive any
requests for a public hearing. All substantive information provided
during the comment period has either been incorporated directly into
this final rule or is addressed below.
During the comment period, we received comments from 31 individuals
addressing the proposed rule, representing 30 public commenters and 1
partner review. Public comments are posted at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R4-ES-2020-0152. Nine public
commenters supported the proposed rule with no additional analysis or
revision requested. These comments are not further addressed. Public
comments that did not provide substantive information that could be
evaluated or incorporated are also not addressed further. Several
public commenters provided substantive information that is addressed
below.
Public Comments
(1) Comment: Several commenters expressed concern that the RRIP,
which has been important in improving conditions in the TVA tailwaters,
will not be continued if the snail darter is delisted. A few commenters
also raised the concern of maintaining tailwater conditions in the
event of TVA privatization.
Our Response: Much of the snail darter's recovery in the mainstem
Tennessee River can likely be tied to the implementation of the RRIP,
which is a suite of dam management practices that results in increased
oxygen and more stable temperatures and flow rates in the tailwaters of
TVA dams. However, as noted above in Summary of Factors Affecting the
Species, the tailwaters inhabited by snail darters are also home to
between 8 and 20 Federally listed mussel species that also require
consistent flows and oxygen below TVA dams. The presence of these
listed species requires that TVA continue to provide suitable
conditions for them in the operation of their dams under the existing
EIS and Operations and Management biological opinion. It is also very
likely that their presence will necessitate continuation of the RRIP
into the future if the biological opinion is revisited. Therefore, we
do not expect the management practices at the dams to change based on
the delisting of the snail darter; we expect that conditions maintained
for other listed species will continue to be suitable for survival of
snail darters. If management conditions are determined to endanger or
threaten the long-term viability of the snail darter such that it meets
the Act's definition of an endangered or threatened species, we can use
our authorities under section 4 the Act, including the emergency
listing authorities at section 4(b)(7), to relist the species as
appropriate.
TVA is a public corporation within the Federal Government, but
there have been considerations to convert it to a nongovernmental
corporation. If TVA is privatized, the operation of the dams in the
Tennessee Valley would no longer be directly managed by a Federal
agency subject to the requirements of section 7 of the Act; however,
the new corporation would still be regulated by the Federal Energy
Regulatory Commission (FERC), which is also required to consult with
the Service under section 7 of the Act to determine if their actions
may affect any listed species. With the presence of federally listed
mussels in the tailwaters, these consultations are unlikely to result
in changes to operations that would negatively affect the tailwater
conditions for the snail darter.
(2) Comment: Some commenters expressed concern that 5 years of
post-delisting monitoring was not enough to ensure continued viability
of the snail darter and recommended that resources for genetic
monitoring are needed to ensure maintenance of genetic diversity.
Our Response: Following delisting, the Act requires the Service to
work with States and other partners to prepare and implement a
monitoring plan for the snail darter for at least 5
[[Page 60311]]
years following the delisting. We have developed a draft post-delisting
monitoring plan for the snail darter in coordination with State and
Federal agencies. The draft post-delisting monitoring plan is based on
TVA's stream IBI monitoring and continuation of the reservoir trawl
surveys for the snail darter. This plan will provide data on the
continued resilience of the species or highlight unexpected declines
and additional threats, should they arise. Five years of post-delisting
monitoring of snail darters is sufficient because it will add to survey
data collected over the past 10 years, which will allow us to look at
the progress of the species over a longer time. Following 5 years of
post-delisting monitoring, TVA will continue to monitor the health of
the watersheds where snail darter is found by conducting IBI surveys.
These surveys are expected to detect future declines of the species,
should they occur. The draft post-delisting monitoring plan can be
found at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R4-ES-2020-
0152.
We acknowledge that sustaining post-delisting monitoring efforts
can be challenging and subject to competing priorities for available
resources given that the Service cannot directly fund monitoring after
a species has been delisted. Nonetheless, we designed a draft post-
delisting monitoring plan that is realistic given limited resources.
While maintaining genetic diversity is important for species
conservation, we were able to make the decision that the snail darter
no longer meets the Act's definition of an endangered or threatened
species without available genetic information. Similarly, we will be
able to assess the viability of the snail darter in the future without
genetic monitoring to determine if the species should be relisted.
(3) Comment: A few commenters expressed concern that delisting the
snail darter without complete population genetics for the species and
without knowing the status of the newly discovered populations as
distinct or descended from the translocated populations is premature.
Our Response: We are required to make our determinations based on
the best available scientific and commercial data at the time the
determination is made. A need for further research on a species is not
necessarily relevant to the question of whether the species meets the
Act's definition of an endangered or threatened species. The presence
of resilient populations in 10 tributaries and 7 mainstem reservoirs
across four physiographic regions provides sufficient evidence of high
redundancy and representation for the species. This abundance and
distribution of self-sustaining snail darter populations in both
tributaries and mainstem reservoirs led us to conclude that the snail
darter does not meet the Act's definition of an endangered or
threatened species. Furthermore, delisting does not prevent continued
research on the species.
While much of the success of the snail darter has come from the
transplantation efforts into the Hiwassee and Holston Rivers, at the
same time as those efforts, populations were found in Sewee Creek,
South Chickamauga Creek, and in Nickajack Reservoir below Chickamauga
Dam and near the mouth of the Sequatchie River. These discoveries
indicate that the snail darter is wider spread than just the lower
Little Tennessee River and that the recently discovered populations
could have been established from multiple sources.
(4) Comment: Several commenters raised concerns with the long-term
impacts of climate change on the snail darter, and one commenter cited
a climate study of the upper Tennessee River Basin that we had not
considered in the proposed rule (Jones et al. 2015).
Our Response: In the proposed rule (86 FR 48953; September 1,
2021), we considered multiple climate models for the Tennessee Valley,
including the RCP 4.5 and RCP 8.5 models (Alder and Hostetler 2013,
entire), interior Southeast models (Mulholland et al. 1997, entire;
Ingram et al. 2013, entire), as well as a meta-analysis potential
climate vulnerability of 700 species of rare and imperiled Appalachian
flora and fauna (Appalachian LCC, 2017). While there was some
variability in the exact predictions, these studies provided evidence
for limited changes from the mean in both temperature and precipitation
before 2050, but that there would be more extreme events, such as
floods and droughts. However, due to the snail darter's larger stream
habitats, it is more resilient to these changes than would be a
headwater or shallow habitat species. We also concluded that the RRIP
would likely further buffer the effects of climate change in the
tailwaters.
The climate study from Jones et al. (2015) used past precipitation
data for the upper Tennessee Valley to investigate trends between 1950
and 2009, with a more complete TVA dataset for 1990-2010. These data
suggested a small but statistically significant decrease in annual
precipitation for most of the subwatersheds investigated, seasonal
variation with increased precipitation in the drier months and a
decrease in the wetter months. However, using the same TVA dataset, 3
of the wettest years on record for the Tennessee Valley were in the
last 5 years. While we anticipate the changes to precipitation from
climate change to be noticeable in the foreseeable future, as mentioned
above, the available evidence suggests that the snail darter will be
resilient to these changes. We have incorporated information from Jones
et al. (2015) and our analysis provided under Summary of Factors
Affecting the Species, above.
Determination of the Snail Darter's Status
Section 4 of the Act (16 U.S.C. 1533) and its implementing
regulations (50 CFR part 424) set forth the procedures for determining
whether a species meets the definition of an endangered species or a
threatened species. The Act defines an ``endangered species'' as a
species 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. For a more
detailed discussion on the factors considered when determining whether
a species meets the definition of an endangered species or a threatened
species and our analysis on how we determine the foreseeable future in
making these decisions, see Regulatory and Analytical Framework, above.
Status Throughout All of Its Range
After evaluating threats to the species and assessing the
cumulative effect of the threats under the Act's section 4(a)(1)
factors, we have found that snail darter representation and redundancy
has increased, with extant populations in 7 mainstem reservoirs of the
Tennessee River and 10 tributaries in the Tennessee River watershed. Of
the mainstem reservoirs, six populations showed multiple age classes,
and for these six, we have observed direct evidence of reproduction in
three populations, indicating moderate or high resilience. Collection
efforts in two mainstem reservoirs, Wilson and Kentucky reservoirs,
failed to find snail darters during our analysis period. Of the
tributaries, nine populations demonstrated moderate to high resilience;
one population is considered to have low resilience with no evidence of
reproduction; three tributary populations (Citico Creek, Flint River,
and Shoal Creek) lacked sufficient collections during our analysis
period to consider them established. Additionally, the species is now
known to be present in four physiographic
[[Page 60312]]
regions indicating increased representation, and the multiple resilient
populations indicate an increase in redundancy since the species was
reclassified to threatened in 1984. Because the snail darter has
increased in representation and redundancy generally, and in particular
with respect to numbers of resilient, self-sustaining populations, we
expect this species to be able to sustain populations into the
foreseeable future.
We have carefully assessed the best scientific and commercial
information regarding the threats faced by the snail darter in
developing this rule. Threats related to habitat loss and curtailment
of range (Factor A) reported at the time of listing in 1975 (40 FR
47505; October 9, 1975) and when we downlisted the species to
threatened status in 1984 (49 FR 27510; July 5, 1984) have been reduced
in many locations. Available data indicate the species possesses
greater resilience to the negative effects of dams than was determined
at the time of listing. Further, beneficial dam operations (i.e., RRIP)
are expected to continue into the foreseeable future.
At the time of the downlisting rule (49 FR 27510; July 5, 1984), it
was thought that the notoriety of the snail darter would result in an
increase in illegal collection (Factor B); however, no such activities
have been seen, and we do not consider this a threat to the current or
future viability of the species. State water quality and wildlife laws
provide some protections to the snail darter and its habitat, and its
range overlaps with other federally protected aquatic animals (Factor
D). In addition, we have evaluated potential effects of climate change
(Factor E) and the evidence indicates that the species is resilient to
the predicted levels of climate change. Thus, after assessing the best
available information, we conclude that the snail darter is not in
danger of extinction or likely to become so throughout all of its range
within the foreseeable future.
Status Throughout a Significant Portion of Its Range
Under the Act and our implementing regulations, a species may
warrant listing if it is in danger of extinction or likely to become so
in the foreseeable future throughout all or a significant portion of
its range. Having determined that the snail darter is not in danger of
extinction or likely to become so throughout all of its range in the
foreseeable future, we now consider whether it may be in danger of
extinction or likely to become so in the foreseeable future in a
significant portion of its range--that is, whether there is any portion
of the species' range for which it is true that both (1) the portion is
significant; and (2) the species is in danger of extinction now or
likely to become so in the foreseeable future in that portion.
Depending on the case, it might be more efficient for us to address the
``significance'' question or the ``status'' question first. We can
choose to address either question first. Regardless of which question
we address first, if we reach a negative answer with respect to the
first question that we address, we do not need to evaluate the other
question for that portion of the species' range.
In undertaking this analysis for the snail darter, we choose to
address the status question first--we consider information pertaining
to the geographic distribution of both the species and the threats that
the species faces to identify any portions of the range where the
species may be endangered or threatened. For the snail darter, we
considered whether the threats are geographically concentrated in any
portion of the species' range on a biologically meaningful scale. We
examined the following threats: habitat modification, curtailment of
range, climate change, and illegal collection, including cumulative
effects.
Threats related to habitat modification or curtailment of range
affect snail darters throughout their range. With the implementation of
TVA's RRIP, conditions around the large dams on the mainstem of the
Tennessee River have improved. Our analysis of the species' resiliency
(see Analytical Framework, above), which integrated information on
demographics and threats, determined that six of the nine reservoir
populations showed multiple age classes and direct evidence of
reproduction in three of the reservoirs. These reservoirs with
resilient populations are distributed across the snail darter's range
and multiple geographic provinces. Of the 10 resilient tributary
populations, 9 populations demonstrated moderate to high resiliency. In
tributary watersheds such as the Ocoee and Sequatchie where water
quality was impacted by localized mining threats, conditions have
improved due in part to the cessation of mining and efforts to clean up
the mine sites. In watersheds with higher levels of agriculture and
urbanization such as the South Chickamauga Creek and Paint Rock River
watersheds, conservation programs are in place to reduce the impact of
these activities on the instream habitat used by the snail darter.
Based on the distribution of resilient populations and the conservation
efforts put in place, we have determined that there are not any
portions of the range where the species may be endangered or threatened
due to habitat modification or curtailment of the range.
We have reviewed other potential threats, including climate change,
illegal collection, and cumulative effects, and concluded that there
are not any portions of the range where the species is endangered or
threatened due to these threats. Therefore, no portion of the species'
range provides a basis for determining that the species is in danger of
extinction now or likely to become so in the foreseeable future in a
significant portion of its range. This does not conflict with the
courts' holdings in Desert Survivors v. U.S. Department of the
Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 2018) and Center for
Biological Diversity v. Jewell, 248 F. Supp. 3d 946, 959 (D. Ariz.
2017) because, in reaching this conclusion, we did not need to consider
whether any portions are significant; and, therefore, we did not apply
the aspects of the definition of ``significant'' in the Final Policy on
Interpretation of the Phrase ``Significant Portion of Its Range'' in
the Endangered Species Act's Definitions of ``Endangered Species'' and
``Threatened Species'' (79 FR 37578; July 1, 2014) that court decisions
held were invalid.
Determination of Status
Our review of the best scientific and commercial data available
indicates that the snail darter does not meet the definition of an
endangered species or a threatened species in accordance with sections
3(6) and 3(20) of the Act. In accordance with our regulations at 50 CFR
424.11(d)(2), the snail darter has recovered. With this rule, we remove
the snail darter from the List of Endangered and Threatened Wildlife.
Effects of This Rule
This final rule revises 50 CFR 17.11(h) by removing the snail
darter from the Federal List of Endangered and Threatened Wildlife. On
the effective date of this rule (see DATES, above), the prohibitions
and conservation measures provided by the Act will no longer apply to
the snail darter. Federal agencies will no longer be required to
consult with the Service under section 7 of the Act in the event that
activities they authorize, fund, or carry out may affect the snail
darter. There is no critical habitat designated for this species, so
there will be no effect to 50 CFR 17.95.
Post-Delisting Monitoring
Section 4(g)(1) of the Act requires us to implement a monitoring
program for not less than 5 years for all species that have been
delisted due to recovery.
[[Page 60313]]
Post-delisting monitoring refers to activities undertaken to verify
that a species delisted due to recovery remains secure from the risk of
extinction after the protections of the Act no longer apply. The
primary goal of post-delisting monitoring is to ensure that the
species' status does not deteriorate and that if a decline is detected,
measures are taken to halt the decline so as to avoid the need to
propose listing of the species again. If at any time during the
monitoring period data indicate that protective status under the Act
should be reinstated, we can initiate listing procedures, including, if
appropriate, emergency listing under section 4(b)(7) of the Act.
Section 4(g) of the Act explicitly requires us to cooperate with the
States in development and implementation of post-delisting monitoring
programs, but we remain responsible for compliance with section 4(g)
and, therefore, must remain actively engaged in all phases of post-
delisting monitoring. We also seek active participation of other
entities that are expected to assume responsibilities for the species'
conservation post-delisting.
Post-Delisting Monitoring Overview
A post-delisting monitoring plan was developed in partnership with
State and Federal agencies. The post-delisting monitoring has been
designed to verify that the snail darter remains secure from risk of
extinction after its removal from the Federal List of Endangered and
Threatened Wildlife by detecting changes in population trends. The Act
has a minimum post-delisting monitoring requirement of 5 years;
however, if populations decline in abundance past the defined threshold
in the post-delisting monitoring plan or a substantial new threat
arises, post-delisting monitoring may be extended or modified, and the
status of the species will be reevaluated.
Post-delisting monitoring will occur for 5 years with the first
year of monitoring beginning after the publication of the final
delisting rule. Post-delisting monitoring will be accomplished by using
TVA's stream IBI monitoring to assess the resilience of tributary
populations. Sites will be surveyed at least once within the 5-year
period, though most will be surveyed two or three times. Reservoir
trawl surveys will also be conducted, and all reservoirs will be
surveyed at least three times during the post-delisting monitoring
period to ensure the continued resilience and recruitment in the
mainstem populations. A draft post-delisting monitoring plan for the
species can be found at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No.
FWS-R4-ES-2020-0152. We will work closely with our partners to maintain
the recovered status of the snail darter and ensure post-delisting
monitoring is conducted and future management strategies are
implemented (as necessary) to benefit the species.
Required Determinations
National Environmental Policy Act (42 U.S.C. 4321 et seq.)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be
prepared in connection with determining a species' listing status under
the Endangered Species Act. We published a notice outlining our reasons
for this determination in the Federal Register on October 25, 1983 (48
FR 49244).
Government-to-Government Relationship With Tribes
In accordance with the President's memorandum of April 29, 1994
(Government-to-Government Relations with Native American Tribal
Governments; 59 FR 22951), Executive Order 13175 (Consultation and
Coordination with Indian Tribal Governments), and the Department of the
Interior's manual at 512 DM 2, we readily acknowledge our
responsibility to communicate meaningfully with recognized Federal
Tribes on a government-to-government basis. In accordance with
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights,
Federal-Tribal Trust Responsibilities, and the Endangered Species Act),
we readily acknowledge our responsibilities to work directly with
Tribes in developing programs for healthy ecosystems, to acknowledge
that Tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to Tribes. There are no Tribal lands associated
with this final rule, and we did not receive any comments from any
Tribes or Tribal members on the proposed rule (86 FR 48953; September
1, 2021).
References Cited
A complete list of all references cited in this final rule is
available on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket
No. FWS-R4-ES-2020-0152, or upon request from the Tennessee Ecological
Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Authors
The primary authors of this final rule are the staff members of the
Fish and Wildlife Service's Species Assessment Team and the Tennessee
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.
Regulation Promulgation
Accordingly, we hereby 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.
Sec. 17.11 [Amended]
0
2. In Sec. 17.11, at paragraph (h), amend the List of Endangered and
Threatened Wildlife by removing the entry for ``Darter, snail'' under
FISHES.
Martha Williams
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2022-21579 Filed 10-4-22; 8:45 am]
BILLING CODE 4333-15-P
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</html>Indexed from Federal Register on October 5, 2022.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.