[Federal Register Volume 83, Number 3 (Thursday, January 4, 2018)]
[Proposed Rules]
[Pages 490-498]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-28491]



Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R4-ES-2017-0094; 4500030113]
RIN 1018-BC52

Endangered and Threatened Wildlife and Plants; Endangered Species 
Status for Barrens Topminnow

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list the Barrens topminnow (Fundulus julisia), a freshwater fish from 
Tennessee, as an endangered species under the Endangered Species Act 
(Act). If we finalize this rule as proposed, it would extend the Act's 
protections to this species.

DATES: We will accept comments received or postmarked on or before 
March 5, 2018. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES, below) must be received by 11:59 
p.m. Eastern Time on the closing date. We must receive requests for 
public hearings, in writing, at the address shown in FOR FURTHER 
INFORMATION CONTACT by February 20, 2018.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. In the Search box, enter FWS-R4-ES-2017-0094, 
which is the docket number for this rulemaking. Then, in the Search 
panel on the left side of the screen, under the Document Type heading, 
click on the Proposed Rules link to locate this document. You may 
submit a comment by clicking on ``Comment Now!''
    (2) By hard copy: Submit by U.S. mail or hand-delivery to: Public 
Comments Processing, Attn: FWS-R4-ES-2017-0094, U.S. Fish and Wildlife 
Service, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
    We request that you send comments only by the methods described 
above. We will post all comments on http://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see Public Comments, below, for more information).

FOR FURTHER INFORMATION CONTACT: Mary Jennings, U.S. Fish and Wildlife 
Service, Tennessee Ecological Services Field Office, 446 Neal Street,

[[Page 491]]

Cookeville, TN 38506; telephone 931-528-6481. Persons who use a 
telecommunications device for the deaf (TDD) may call the Federal Relay 
Service at 800-877-8339.


Information Requested

Public Comments

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other concerned governmental agencies, 
Native American tribes, the scientific community, industry, or any 
other interested parties concerning this proposed rule. We particularly 
seek comments concerning:
    (1) The Barrens topminnow's biology, range, and population trends, 
    (a) Biological or ecological requirements of the species, including 
habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns;
    (d) Historical and current population levels, and current and 
projected trends; and
    (e) Past and ongoing conservation measures for the species, its 
habitat, or both.
    (2) Factors that may affect the continued existence of the species, 
which may include habitat modification or destruction, overutilization, 
disease, predation, the inadequacy of existing regulatory mechanisms, 
or other natural or manmade factors.
    (3) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this species and existing regulations 
that may be addressing those threats.
    (4) Additional information concerning the historical and current 
status, range, distribution, and population size of this species, 
including the locations of any additional populations of this species.
    (5) Information related to climate change within the range of the 
Barrens topminnow and how it may affect the species' habitat.
    (6) The reasons why areas should or should not be designated as 
critical habitat as provided by section 4 of the Act (16 U.S.C. 1531 et 
    (7) Specific information on:
    (a) What areas, that are currently occupied and that contain the 
physical and biological features essential to the conservation of the 
Barrens topminnow, should be included in a critical habitat designation 
and why;
    (b) Special management considerations or protection that may be 
needed for the essential features in potential critical habitat areas, 
including managing for the potential effects of climate change; and
    (c) What areas not occupied at the time of listing are essential 
for the conservation of the species and why.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for or 
opposition to the action under consideration without providing 
supporting information, although noted, will not be considered in 
making a determination, as section 4(b)(1)(A) of the Act directs that 
determinations as to whether any species is an endangered or threatened 
species must be made ``solely on the basis of the best scientific and 
commercial data available.''
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in ADDRESSES.
    If you submit information via http://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the website. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on http://www.regulations.gov.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on http://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Tennessee Ecological Services Field Office (see FOR 

Public Hearing

    Section 4(b)(5) of the Act requires us to conduct one or more 
public hearings on this proposal, if requested. Requests for a public 
hearing must be received within 45 days after the date of publication 
of this proposed rule in the Federal Register (see DATES, above) and 
must be sent to the address shown in FOR FURTHER INFORMATION CONTACT. 
We will schedule public hearings on this proposal, if requested, and 
announce the dates, times, and places of those hearings, as well as how 
to obtain reasonable accommodations, in the Federal Register and local 
newspapers at least 15 days before the hearing.

Peer Review

    The purpose of peer review is to ensure that our listing 
determination is based on scientifically sound data, assumptions, and 
analyses. In accordance with our joint policy on peer review published 
in the Federal Register on July 1, 1994 (59 FR 34270), and our August 
22, 2016, memorandum updating and clarifying the role of peer review of 
listing actions under the Act, we sought the expert opinions of six 
appropriate specialists regarding the species status assessment (SSA) 
that informed this proposed rule. All of the peer reviewers have 
expertise in fish biology, habitat, and stressors to the Barrens 
topminnow. We received a response from one of the six peer reviewers, 
which we took into account in our SSA and this proposed rule. We invite 
any additional comment from the peer reviewers on the proposed rule 
during this public comment period; all comments received from peer 
reviewers will be available, along with other public comments, in the 
docket for this proposed rule on http://www.regulations.gov.

Previous Federal Actions

    The Barrens topminnow was initially proposed to be listed as 
endangered under the Act in 1977 (42 FR 65209; December 30, 1977). 
Because of comments received on the proposed critical habitat, the 
listing was postponed, and critical habitat was reproposed in 1979 (44 
FR 44418; July 27, 1979); however, the proposed listing rule was 
withdrawn in 1980, because it was not finalized within the required 2 
years (45 FR 5782; January 24, 1980, effective December 30, 1979). The 
Barrens topminnow was designated a Category 2 candidate species in 1982 
(47 FR 58454; December 30, 1982) until that list was discontinued in 
1996 (61 FR 7596; February 28, 1996), and it was not added to the 
revised candidate list. In 2010, the Center for Biological Diversity 
(CBD) petitioned the Service to list 404 aquatic, riparian, and wetland 
species from the southeastern United States, including the Barrens 
topminnow, as endangered or threatened under the Act. On September 27, 
2011, the Service published a substantial 90-day finding for 374 of the 
404 species, including the Barrens topminnow, soliciting information 
about, and initiating status reviews for, those species (76 FR 59836). 
In 2015, CBD filed a complaint against the Service for failure to 

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complete a 12-month finding for the Barrens topminnow. In 2016, the 
Service entered into a settlement agreement with CBD, which specified 
that a 12-month finding for the Barrens topminnow would be delivered to 
the Federal Register by December 31, 2017.


    A thorough review of the taxonomy, life history, ecology, and 
overall viability of the Barrens topminnow (Fundulus julisia) is 
presented in the SSA (Service 2017; available at http://www.regulations.gov). In the SSA, we summarize the relevant biological 
data and a description of past, present, and likely future stressors, 
and conduct an analysis of the viability of the species. The SSA 
documents the results of the comprehensive biological status review for 
the Barrens topminnow, provides an account of the species' overall 
viability through forecasting of the species' condition in the future, 
and provides the scientific basis that informs our regulatory decision 
regarding whether this species should be listed as an endangered or 
threatened species under the Act as well as the risk analysis on which 
the determination is based (Service 2017, entire). The following 
discussion is a summary of the results and conclusions from the SSA.

Species Description

    The Barrens topminnow is a small, colorful fish that grows to 98 
millimeters (mm) (3.9 inches (in)). As is typical of its genus, 
Fundulus, the Barrens topminnow has an upturned mouth, flattened head 
and back, and rounded fins with the unpaired fins set far back on the 
body (Etnier and Starnes 1993, pp. 360-361). Reproductive males are 
very showy with bright, iridescent background colors of greens and 
blues, with reddish orange spots and yellow fins as well as tubercles 
(hardened projections) on the anal fin rays. Females, juveniles, and 
non-reproductive males are drabber, with pale brown bodies sprinkled 
with darker spots on the sides (Williams and Etnier 1982, entire; 
Etnier and Starnes 1993, pp. 365-366). A detailed description of scale 
and fin ray counts and other morphological features is provided in 
Williams and Etnier (1982, entire) and Etnier and Starnes (1993, p. 

Reproduction and Lifespan

    Barrens topminnows spawn in filamentous algae near the water 
surface, between April and August, with peak activity occurring from 
May to June. Spawning occurs on multiple occasions, with a few eggs 
released during each spawning event. By the end of the spawning season, 
up to 300 eggs are released. While the maximum age of the Barrens 
topminnow is 4 years, adults typically live for 2 years or less, and 
only about one-third of individuals spawn more than one season (Rakes 
1989, p. 42; Etnier and Starnes 1993, p. 366). Most individuals mature 
and spawn within the first year, though some of the later spawned fish 
are in year 2 before they spawn (Rakes 1989, entire).
    Prey items consumed by Barrens topminnows consist predominantly of 
microcrustaceans and immature aquatic insect larvae. However, the 
species is a generalist feeder, also consuming small snails and 
terrestrial organisms such as ants and other insects that fall or 
wander into aquatic habitats (Rakes 1989, pp. 18-25).

Habitat and Range

    Barrens topminnow habitat is restricted to springhead pools and 
slow-flowing areas of spring runs on the Barrens Plateau in middle 
Tennessee. These fish are strongly associated with abundant aquatic 
vegetation such as filamentous algae (e.g., Cladophora and Pithophora), 
watercress (Nasturtium officinale), rushes (Juncus), pondweed 
(Potamogeton), and eelgrass (Vallisneria), and will occasionally 
shelter under overhanging terrestrial plants and tree roots. Barrens 
topminnows have only been found in streams where the predominant source 
of base flow is groundwater. Due to the groundwater influence of these 
habitats, temperatures are relatively stable, ranging from 15 to 25 
degrees Celsius ([deg]C) (59 to 77 degrees Fahrenheit ([deg]F)). The 
karst topography of the Barrens Plateau results in the presence of a 
number of spring systems, though not all of these have been inhabited 
by the Barrens topminnow. In times of drought, if the discharge of the 
springs is severely reduced, Barrens topminnows likely move downstream 
into more permanent water if suitable habitat is available.
    Historically, Barrens topminnows were found in Cannon, Coffee, and 
Warren Counties of Tennessee in three river systems, the Elk River, 
Duck River, and Caney Fork River. The Elk River and Duck River flow to 
the Tennessee River, and the Caney Fork River flows to the Cumberland 
River. The small streams or springs inhabited by Barrens topminnows in 
each river system are separated by hundreds of miles of intervening, 
unsuitable, larger stream habitat; therefore the individual populations 
are isolated and cannot come into contact with other populations by 
moving downstream. Within these three systems, the Barrens topminnow 
was known to occur in at least 18 sites (Hurt et al. 2017, p. 2). It is 
likely that many more sites were occupied, but were either not surveyed 
due to lack of access to private land, or were modified to be 
incompatible with Barrens topminnow presence for uses such as watering 
livestock before surveys could be conducted.
    Currently, the Barrens topminnow occurs in five sites: Marcum 
Spring (Ovaca Spring), Short Spring, Benedict Spring, McMahan Creek, 
and Greenbrook Pond. Marcum Spring and Short Spring are in the Duck 
River system. The remaining three springs are in the Caney Fork River 
system. Benedict Spring and McMahan Creek are occupied by native stock, 
while the three other occupied sites were reestablished with 
individuals from the Caney Fork system (see discussion under 
Conservation Actions and Regulatory Mechanisms, below). Greenbrook 
Pond, although it ultimately drains to the Caney Fork, is outside the 
known historical range of the species, in Dekalb County, Tennessee. 
Although no longer extant at its native locality, the Pond Spring 
population from the Elk River system is maintained in captivity at 
three facilities. Collectively, these captively held topminnows form an 
``ark population'' that is managed as part of a conservation strategy 
that will enable release back into the wild if Pond Spring can be 
    Estimates of current population size by site are lacking, but 
recent surveys (Kuhajda et al. 2014, entire; Kuhajda 2017, entire) 
reported the number of Barrens topminnows captured (Table 1, below), 
providing a rough approximation of the number of topminnows in each 
population. Based on these samples, Benedict Spring, Marcum Spring, and 
Greenbrook Pond had fairly robust populations, with at least, or likely 
with more than, 100 individuals. The population in McMahan Creek 
appeared to be small relative to other occupied sites, but this 
difference is at least partly an artifact of sampling bias. In stream 
habitat such as McMahan Creek, habitat structure makes it easier for 
fish to avoid the seine, and fish tend to be more broadly dispersed 
than they are in pond-like spring habitats.

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  Table 1--Number of Barrens Topminnows Captured by Site (Kuhajda 2017,
 Entire) McMahan Creek Number From 2017 Sampling (Service, Unpublished)
                          Site                               captured
Benedict Spring.........................................      100 (2016)
McMahan Creek...........................................       10 (2017)
Marcum Spring...........................................      132 (2015)
Short Spring............................................       30 (2015)
Greenbrook Pond.........................................       91 (2015)

Species Needs

    In this section, we describe the needs of the species at the 
individual, population, and species level. We describe the Barrens 
topminnow's viability needs in terms of resiliency (ability of the 
populations to withstand stochastic events), redundancy (ability of the 
species to withstand large-scale, catastrophic events), and 
representation (the ability of the species to adapt to changing 
environmental conditions). In later sections, using various time frames 
and the current and projected resiliency, redundancy, and 
representation, we will describe the species' viability over time.
    Barrens topminnows need filamentous algae or other submerged 
vegetation for egg deposition and cover, and consistently cool water 
ranging from 15 to 25 [deg]C (59 to 77 [deg]F) that is sufficiently 
clear for mating display (Rakes, 1989, entire). For feeding, they need 
microcrustaceans and immature aquatic insect larvae (Rakes 1989, pp. 
18-25). At the larval and juvenile stage, it is essential that 
predation rates and competition from other fishes is low (Laha and 
Mattingly 2006, pp. 1, 6-10).
    For the Barrens topminnow to maintain viability, its populations or 
some portion thereof must be resilient. Stochastic events that affect 
resiliency are reasonably likely to occur infrequently, but are of a 
magnitude that can drastically alter the ecosystem where they happen. 
Classic examples of stochastic events include drought, major storms 
(hurricanes), fire, and landslides (Chapin et al. 2002, pp. 285-288). 
To be resilient to stochastic events populations of Barrens topminnow 
need to be sufficiently abundant, with several hundred individuals 
(Service 2017, p. 11) represented by adult and juvenile age classes. 
The larger the range, or spatial extent, occupied by a Barrens 
topminnow population, the more resilient the population will be to a 
stochastic event. Additionally, populations need to exist in locations 
where environmental conditions provide suitable habitat and water 
quality such that adequate numbers of individuals can be supported. 
Without all of these factors, a population has an increased likelihood 
of extirpation.
    Maintaining representation in the form of genetic diversity is 
important to the Barrens topminnow's capacity to adapt to environmental 
changes. Ecological diversity, another measure of species' 
representation, is naturally low, as the Barrens topminnow has always 
been restricted to spring habitats in a single physiographic province. 
Based on mitochondrial DNA, genetic variation of extant populations is 
extremely low, and there are fixed differences between the Caney Fork 
system populations and the Elk River system population (Hurt et al. 
2017, pp. 1, 5), which is from Pond Spring and is represented now only 
by individuals held in captivity. The captive Elk River population, for 
which there are two identified mitochondrial DNA haplotypes unique from 
the third haplotype present in all Caney Fork system sampled fish, 
should be considered an evolutionary significant unit (ESU) (Hurt et 
al. 2017, p. 5), a historically isolated population that is on an 
independent evolutionary trajectory (Moritz 1994, p. 373). Accordingly, 
reestablishing the captive Elk River population in the wild will be 
important to increasing genetic representation and species' viability.
    Finally, the Barrens topminnow needs to have multiple resilient 
populations distributed throughout its range to provide redundancy, the 
ability of the species to withstand catastrophic events. The more 
populations, and the wider the distribution of those populations, the 
more redundancy the species will exhibit. Redundancy reduces the risk 
that a large portion of the species' range will be negatively affected 
by a catastrophic natural or anthropogenic event at a given point in 
time. Species that are well-distributed across their historical range 
are considered less susceptible to extinction and have higher viability 
than species confined to a small portion of their range (Carroll et al. 
2010, entire; Redford et al. 2011, entire).

Summary of Biological Status and Threats

    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 is an ``endangered species'' or a ``threatened 
species.'' The Act defines an endangered species as a species that is 
``in danger of extinction throughout all or a significant portion of 
its range,'' and a threatened species as a species that is ``likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range.'' The Act directs us to 
determine whether any species is an endangered species or a threatened 
species because of one or more of the following factors affecting its 
continued existence: (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 for those that may ameliorate any negative effects and those 
that may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). A threat may 
encompass--either together or separately--the source of the action or 
condition, or the action or condition itself.
    However, the mere identification of any threat(s) does not 
necessarily mean that the species meets the statutory definition of an 
``endangered species'' or a ``threatened species.'' In determining 
whether a species meets either definition, we must evaluate all 
identified threats by considering the expected response by the species, 
and the effects of the threats--in light of those actions and 
conditions that will ameliorate the threats--on an individual, 
population, and species level. We evaluate each threat and its expected 
effects on the species, then analyze the cumulative effect of all of 
the threats on the species as a whole. We also consider the cumulative 
effect of the threats in light of those actions and conditions that 
will have positive effects on the species--such as any

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existing regulatory mechanisms or conservation efforts. It is only 
after conducting this cumulative analysis of threats and the actions 
that may ameliorate them or have positive effects on the species, and 
describing the expected effect on the species now and in the 
foreseeable future, that the Secretary can determine whether the 
species meets the definition of an ``endangered species'' or a 
``threatened species.'' We completed a comprehensive assessment of the 
biological status of the Barrens topminnow, and prepared a report of 
the assessment which provides a thorough account of the species' 
overall viability and evaluates the cumulative effects of the five 
listing factors (Service 2017, entire).

Risk Factors

    In the SSA, we assessed the potential risk factors (i.e., threats, 
stressors) that could be affecting the Barrens topminnow now and in the 
future. In this proposed rule, we will discuss only those factors in 
detail that could meaningfully impact the status of the species. Those 
risks that are not known to have effects on Barrens topminnow 
populations, such as collection and disease, are not discussed here.
    The primary risk factor affecting the status of the Barrens 
topminnow is western mosquitofish (Gambusia affinis), a species 
invasive to the Barrens Plateau that preys on young topminnows, 
harasses older individuals, and may compete with adults for space and 
food (Factor C).
    Western mosquitofish are native to Tennessee, but their range 
within the State was most likely confined to the Coastal Plain province 
(Etnier and Starnes 1993, p. 373), and they are not native to the 
Barrens Plateau. In many parts of North America, western mosquitofish 
were stocked in attempt to control mosquito larvae, which is presumably 
the means by which they were introduced to the Barrens Plateau in the 
mid twentieth century. Although to the best of our knowledge 
mosquitofish stocking stopped shortly thereafter, the species has 
spread and become a permanent inhabitant throughout most of the Barrens 
Plateau. Mosquitofish are well adapted to spread in habitats where they 
are introduced because they reproduce rapidly, spawning three to four 
cohorts per year of a few to a hundred or more individuals (Etnier and 
Starnes 1993, p. 373). They can move through very shallow water and 
have invaded sites connected by temporarily wetted areas created by 
floods. Mosquitofish prey on young topminnows and harass adults, 
causing recruitment failure such that only the adult age class remains 
after a spawning season (Goldsworthy and Bettoli 2006, p. 341; Laha and 
Mattingly 2007, p. 9). Under most circumstances, extirpation of Barrens 
topminnows occurs within 3 to 5 years of mosquitofish invading a site 
(Service 2017, p. 32). The five extant Barrens topminnow populations 
are at sites free of mosquitofish.
    As a consequence of the western mosquitofish invasion, the habitat 
available to the Barrens topminnow, and the species' range, has been 
curtailed (Factor A). Historically, Barrens topminnow populations were 
likely connected by floods and high flow events that washed individuals 
downstream or provided temporary connections across local stream 
divides. Most, if not all, pathways via flood-facilitated migration are 
no longer viable owing to the presence of mosquitofish. Many of the 
sites where the topminnow is extirpated currently have sufficient 
habitat quality to support populations (Kuhajda et al. 2014, entire; 
Kuhajda 2017, entire). Thus, it is the presence of mosquitofish rather 
than habitat that is limiting Barrens topminnow populations because 
mosquitofish prevent topminnows from colonizing previously occupied 
springs in their range. This reduction in connectivity contributes to 
reduced gene flow, which in turn reduces genetic diversity and species' 
representation. Additionally, the lost connectivity contributes to the 
diminished range (number of occupied sites), which has caused a 
reduction in species' redundancy.
    Reduced habitat availability has exacerbated the threat of drought 
(Factor E), which has greatest effect on one of the two remaining 
native populations, at Benedict Spring. Approximately once every 5 
years, drought results in Benedict Spring drying completely or nearly 
so, to the point that it can no longer support the Barrens topminnow. 
In these years, all topminnows are removed from Benedict Spring and 
placed in aquaria, where they are held until water levels return. Under 
natural (i.e., mosquitofish free) conditions, drought would not be a 
concern because Barrens topminnows would recolonize areas in wetter 
years; however, due to the widespread reduction in suitable habitat due 
to mosquitofish and the resulting small number of remaining 
populations, the loss of any population is a concern.

Conservation Actions and Regulatory Mechanisms

    There have been many targeted efforts since circa 1980 to conserve 
the Barrens topminnow. Without these efforts it is likely the species 
would persist only at one site, McMahan Spring, which has not gone dry 
during periods of drought and is not occupied by mosquitofish. In 2001, 
the Barrens Topminnow Working Group, consisting of the Tennessee 
Wildlife Resources Agency, the Service, universities, and nonprofit 
organizations, was created to coordinate actions such as habitat 
improvement, propagation, and reintroduction of the species in the 
wild. Since the initiation of the stocking program, more than 44,000 
Barrens topminnows have been reintroduced in 27 sites deemed to have 
appropriate habitat. Brood fish were taken from McMahan Creek and 
Benedict Spring in the Caney Fork watershed, and Pond Spring in the Elk 
River watershed. Reintroduction was unsuccessful at most of these 
sites, either because of insufficient or marginal habitat or the 
invasion of mosquitofish (Goldsworth and Bettoli 2005, entire). At the 
2016 Working Group meeting, the decision was made to stop the stocking 
program because it was no longer needed to maintain populations at 
suitable sites that lack mosquitofish, and at other sites, continued 
stocking was unlikely to establish self-sustaining populations.
    One of the stocked sites, Vervilla Spring, was situated in the 
Caney Fork watershed on land opportunistically purchased by the Service 
for Barrens topminnow reintroduction. When the land came under the 
management of Tennessee National Wildlife Refuge, mosquitofish were 
present in the spring on the property and topminnows were not. To 
improve habitat for topminnows at the site, spring pools were deepened, 
a concrete low water barrier was installed, and the mosquitofish 
removed with a piscicide. Topminnows from Benedict Spring were then 
stocked above the barrier. This population was stocked in 2001, and 
maintained viability until 2010, when mosquitofish reinvaded the spring 
during a flood. In 2011, only adults were present, and by 2013, no 
Barrens topminnows remained in Vervilla Spring.
    From the late 1980s into the 2000s, the Service's Partners for Fish 
and Wildlife program worked with landowners to exclude livestock from 
the springs and spring runs where Barrens topminnows occurred in an 
effort to curb sedimentation. None of these Partners agreements is 
currently active. However, there are still buffers that exclude 
livestock from topminnow habitat in place at some sites, many which 
have since been invaded by mosquitofish.

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Current Condition

    As discussed above, only five remaining populations of Barrens 
topminnow remain (see Table 1, above), in contrast to at least 18 
identified historical populations (occupied sites) and likely several 
more that were extirpated without having been first identified. Thus, 
there has been at least a 72 percent reduction in the number of 
populations in the wild. Furthermore, the number of native populations 
has been reduced by at least 89 percent. The only population known to 
be native in the Elk River watershed, from Pond Spring, is now 
maintained as a captive ``ark population'' at three facilities. In the 
Duck River system, native populations were extirpated by the late 1960s 
(Etnier and Starnes 1993, p. 366), and if there was any genetic 
component unique to the Duck River system, it has been lost. The only 
two remaining native populations are at Benedict Spring and McMahan 
    In summary, the current condition for each of the conservation 
metrics of resiliency, redundancy, and representation is low. Regarding 
resiliency, four of the five extant populations are of moderate size, 
likely with 100 individuals or more. The other population is smaller, 
although based on recent surveys it appears to be persisting and 
recruiting new cohorts each year. However, even if the number of 
individuals in each population is sufficient to maintain future 
generations, all currently occupied sites are small and vulnerable to 
stochastic events, so that a disturbance would adversely affect a site 
and its whole population equally. Regarding redundancy, at least 16 of 
18 native populations (89 percent) have been lost, with only 5 
populations remaining in the wild. Thus, the spatial distribution of a 
naturally narrow-ranging endemic has become more concentrated, making 
the species more susceptible to a catastrophic event. Lastly, 
representation has been reduced and the species' adaptive capacity may 
be limited as there is little genetic variation between extant 
populations. Native stock from the Elk River and Duck River has been 
extirpated, although members of the Elk River population survive in 

Future Condition

    As part of the SSA, we developed three future condition scenarios 
to capture the range of uncertainties regarding future threats and the 
projected responses by the Barrens topminnow. Our scenarios included a 
status quo scenario, which incorporated the current risk factors 
continuing on the same trajectory that they are on now. We also 
evaluated a best case scenario, under which management actions to 
exclude mosquitofish and reintroduce populations would occur. Finally, 
we evaluated a worst case scenario, under which no management actions 
would be applied and climate change would increase the frequency and 
magnitude of droughts and floods. Regarding the likelihood of each 
scenario transpiring, in the near future (3- to 5-year time frame), the 
status quo scenario was predicted to be ``very likely'' and best case 
and worst case scenarios were ``unlikely.'' For the SSA, the terms 
``very likely'' and ``unlikely'' as they apply to confidence are 70-90 
percent certain and 10-40 percent certain, respectively (IPCC 2014, p. 
2). In 20 to 30 years, the time frame constituting the extent of the 
foreseeable future, beyond which there is insufficient confidence in 
how threats will act, the best case scenario was predicted to be 
``unlikely'' and the status quo and worst case scenarios were ``as 
likely as not,'' defined as having a 40-70 percent certainty of 
occurrence (IPCC 2014, p. 2). Because we determined that the current 
condition of the Barrens topminnow was consistent with that of an 
endangered species (see Determination, below), and that it is very 
likely the current condition will persist through the near future, we 
are not presenting in any more detail how each scenario would likely 
act on species viability. Please refer to the SSA (Service 2017, pp. 
32-42) for the full analysis of future scenarios.


    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 ``endangered species'' or 
``threatened species.'' The Act defines an endangered species as any 
species that is ``in danger of extinction throughout all or a 
significant portion of its range'' and a threatened species as any 
species ``that is likely to become endangered throughout all or a 
significant portion of its range within the foreseeable future.'' We 
have carefully assessed the best scientific and commercial information 
available and find that the Barrens topminnow is presently in danger of 
extinction throughout its entire range based on the severity and 
immediacy of threats currently impacting the species.
    The overall range of the Barrens topminnow has been significantly 
reduced (Factor A), and its remaining populations are threatened by 
mosquitofish (Factor C), drought, and small population size (Factor E) 
acting in combination to reduce the overall viability of the species. 
The risk of extinction is high because the remaining populations have a 
high risk of extirpation, are isolated, and have no potential for 
recolonization without intervening management actions. Therefore, on 
the basis of the best available scientific and commercial information, 
we propose listing the Barrens topminnow as endangered in accordance 
with sections 3(6) and 4(a)(1) of the Act. We find that a threatened 
species status is not appropriate for the Barrens topminnow, as it is 
already in danger of extinction throughout its range because of the 
currently contracted range (loss of 79 percent of occupied sites), 
because the threats are occurring across the entire range of the 
species, and because the threats are ongoing currently and are expected 
to continue into the future.
    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. Because we have determined that the 
Barrens topminnow is endangered throughout all of its range, no portion 
of its range can be ``significant'' for purposes of the definitions of 
``endangered species'' and ``threatened species.'' See 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).

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness and 
conservation by Federal, State, Tribal, and local agencies; private 
organizations; and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies and 
the prohibitions against certain activities are discussed, in part, 
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Subsection 4(f) of the Act calls for the Service to develop

[[Page 496]]

and implement recovery plans for the conservation of endangered and 
threatened species. The recovery planning process involves the 
identification of actions that are necessary to halt or reverse the 
species' decline by addressing the threats to its survival and 
recovery. The goal of this process is to restore listed species to a 
point where they are secure, self-sustaining, and functioning 
components of their ecosystems.
    Recovery planning includes the development of a recovery outline 
when a species is listed and preparation of a draft and final recovery 
plan. The recovery outline guides the immediate implementation of 
urgent recovery actions and describes the process to be used to develop 
a recovery plan. Subsequently, a recovery plan identifies recovery 
criteria for review of when a species may be ready for downlisting or 
delisting, and methods for monitoring recovery progress. Recovery plans 
also establish a framework for agencies to coordinate their recovery 
efforts and provide estimates of the cost of implementing recovery 
tasks. Recovery teams (composed of species experts, Federal and State 
agencies, nongovernmental organizations, and stakeholders) are often 
established to develop recovery plans. Revisions of the plan may be 
done to address continuing or new threats to the species, as new 
substantive information becomes available. We intend to make a recovery 
outline available to the public concurrent with the final listing rule, 
if listing continues to be warranted. When completed, the recovery 
outline, draft recovery plan, and the final recovery plan will be 
available on our website (http://www.fws.gov/endangered), or from our 
Tennessee Ecological Services Field Office (see FOR FURTHER INFORMATION 
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their ranges may occur primarily or solely on 
non-Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands. 
If this species is listed, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the State of Tennessee would be 
eligible for Federal funds to implement management actions that promote 
the protection or recovery of the Barrens topminnow. Information on our 
grant programs that are available to aid species recovery can be found 
at: http://www.fws.gov/grants.
    Although the Barrens topminnow is only proposed for listing under 
the Act at this time, please let us know if you are interested in 
participating in recovery efforts for this species. Additionally, we 
invite you to submit any new information on this species whenever it 
becomes available and any information you may have for recovery 
planning purposes (see FOR FURTHER INFORMATION CONTACT).
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as an 
endangered or threatened species and with respect to its critical 
habitat, if any is designated. Regulations implementing this 
interagency cooperation provision of the Act are codified at 50 CFR 
part 402. Section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any action that is likely to jeopardize the 
continued existence of a species proposed for listing or result in 
destruction or adverse modification of proposed critical habitat. If a 
species is listed subsequently, section 7(a)(2) of the Act requires 
Federal agencies to ensure that activities they authorize, fund, or 
carry out are not likely to jeopardize the continued existence of the 
species or destroy or adversely modify its critical habitat. If a 
Federal action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into consultation with the 
    Federal agency actions within the species' habitat that may require 
conference or consultation or both as described in the preceding 
paragraph include issuance of section 404 Clean Water Act (33 U.S.C. 
1251 et seq.) permits by the U.S. Army Corps of Engineers, construction 
and maintenance of roads or highways by the Federal Highway 
Administration, construction and maintenance of utility corridors by 
the Tennessee Valley Authority, and construction and maintenance of 
natural gas or oil pipeline corridors by the Federal Energy Regulatory 
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to endangered wildlife. 
The prohibitions of section 9(a)(1) of the Act, codified at 50 CFR 
17.21, make it illegal for any person subject to the jurisdiction of 
the United States to take (which includes harass, harm, pursue, hunt, 
shoot, wound, kill, trap, capture, or collect; or to attempt any of 
these) endangered wildlife within the United States or on the high 
seas. In addition, it is unlawful to import; export; deliver, receive, 
carry, transport, or ship in interstate or foreign commerce in the 
course of commercial activity; or sell or offer for sale in interstate 
or foreign commerce any listed species. It is also illegal to possess, 
sell, deliver, carry, transport, or ship any such wildlife that has 
been taken illegally. Certain exceptions apply to employees of the 
Service, the National Marine Fisheries Service, other Federal land 
management agencies, and State conservation agencies.
    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits are codified at 50 CFR 17.22. With regard to 
endangered wildlife, a permit may be issued for the following purposes: 
For scientific purposes, to enhance the propagation or survival of the 
species, and for incidental take in connection with otherwise lawful 
activities. There are also certain statutory exemptions from the 
prohibitions, which are found in sections 9 and 10 of the Act.
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of a proposed 
listing on proposed and ongoing activities within the range of the 
species proposed for listing. Based on the best available information, 
if we list this species, the following actions are unlikely to result 
in a violation of section 9, if these activities are carried out in 
accordance with existing regulations and permit requirements; this list 
is not comprehensive:
    (1) Normal agricultural and silvicultural practices, including 
herbicide and pesticide use, which are carried out in accordance with 
any existing regulations, permit and label requirements, and best 
management practices; and
    (2) Normal residential landscape activities.
    Based on the best available information, if we list this species, 

[[Page 497]]

following activities may potentially result in a violation of section 9 
of the Act; this list is not comprehensive:
    (1) Intentional release of mosquitofish into occupied Barrens 
topminnow habitat;
    (2) Unauthorized handling or collecting of the species;
    (3) Modification of the water flow of any spring or stream in which 
the Barrens topminnow is known to occur;
    (4) Direct or indirect destruction of stream habitat; and
    (5) Discharge of chemicals or fill material into any waters in 
which the Barrens topminnow is known to occur.
    Questions regarding whether specific activities would constitute a 
violation of section 9 of the Act should be directed to the Tennessee 
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

Critical Habitat


    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features:
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary.
    Such methods and procedures include, but are not limited to, all 
activities associated with scientific resources management such as 
research, census, law enforcement, habitat acquisition and maintenance, 
propagation, live trapping, and transplantation, and, in the 
extraordinary case where population pressures within a given ecosystem 
cannot be otherwise relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the destruction or adverse modification of 
critical habitat. The designation of critical habitat does not affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. Such designation does not allow the government 
or public to access private lands. Such designation does not require 
implementation of restoration, recovery, or enhancement measures by 
non-Federal landowners. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the consultation requirements of section 7(a)(2) 
of the Act would apply, but even in the event of a destruction or 
adverse modification finding, the obligation of the Federal action 
agency and the landowner is not to restore or recover the species, but 
to implement reasonable and prudent alternatives to avoid destruction 
or adverse modification of critical habitat.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658), 
and our associated Information Quality Guidelines, provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 

Prudency Determination

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12), require that, to the maximum extent 
prudent and determinable, the Secretary designate critical habitat at 
the time the species is determined to be endangered or threatened. Our 
regulations (50 CFR 424.12(a)(1)) state that the designation of 
critical habitat is not prudent when one or both of the following 
situations exist: (1) The species is threatened by taking or other 
human activity, and identification of critical habitat can be expected 
to increase the degree of threat to the species, or (2) such 
designation of critical habitat would not be beneficial to the species.
    As discussed above and in the SSA, there is currently no imminent 
threat to the Barrens topminnow of take attributed to collection or 
vandalism (Factor B), and identification and mapping of critical 
habitat would not likely to increase any such threat. In the absence of 
finding that the designation of critical habitat would increase threats 
to a species, if there are any benefits to a critical habitat 
designation, then a prudent finding is warranted. The potential 
benefits of designation include: (1) Triggering consultation under 
section 7 of the Act in new areas for actions in which there may be a 
Federal nexus where it would not otherwise occur because, for example, 
it is or has become unoccupied or the occupancy is in question; (2) 
focusing conservation activities on the most essential features and 
areas; (3) providing educational benefits to State or county 
governments or private entities; and (4) preventing people from causing 
inadvertent harm to the species. Therefore, because we have determined 
that the designation of critical habitat will not likely increase the 
degree of threat to these species and may provide some measure of 
benefit, we find that designation of critical habitat is prudent for 
the Barrens topminnow.

Critical Habitat Determinability

    Having determined that designation is prudent, under section 
4(a)(3) of the Act we must find whether critical habitat for the 
species is determinable. Our regulations at 50 CFR 424.12(a)(2) state 
that critical habitat is not determinable when one or both of the 
following situations exist: (1) Information sufficient to perform 
required analyses of the impacts of the designation is lacking, or (2) 
The biological needs of the species are not sufficiently well known to 
permit identification of an area as critical habitat. As discussed 
above, we have reviewed the available information pertaining to the 
biological needs of this species and the habitat characteristics where 
this species is located. However, a careful assessment of the economic 
impacts that may occur due to a critical habitat designation is 
ongoing, and we are in the process of working with the States and other 
partners in acquiring the complex information needed to perform that 
assessment. Until these efforts are complete, information sufficient to 
perform a required analysis of the impacts of the designation is 
lacking, and, therefore, we find designation of critical habitat for 
this species to be not determinable at this time. However, we

[[Page 498]]

expect to have the necessary information, and publish a proposed rule 
in the Federal Register, in the near future.

Required Determinations

Clarity of the Rule

    We are required by Executive Orders 12866 and 12988 and by the 
Presidential Memorandum of June 1, 1998, to write all rules in plain 
language. This means that each rule we publish must:
    (1) Be logically organized;
    (2) Use the active voice to address readers directly;
    (3) Use clear language rather than jargon;
    (4) Be divided into short sections and sentences; and
    (5) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in ADDRESSES. To better help us 
revise the rule, your comments should be as specific as possible. For 
example, you should tell us the numbers of the sections or paragraphs 
that are unclearly written, which sections or sentences are too long, 
the sections where you feel lists or tables would be useful, etc.

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

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act, need not be prepared in connection with 
listing a species as an endangered or threatened species 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 

References Cited

    A complete list of references cited is available in Appendix A of 
the SSA (Service 2017. Species Status Assessment Report for the Barrens 
Topminnow (Fundulus julisia), Version 1.0. Cookeville, TN), available 
online at http://www.regulations.gov under Docket No. FWS-R4-ES-2017-


    The primary authors of this proposed rule are the staff members of 
the Tennessee Ecological Services Field Office.

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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


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.
 2. Amend Sec.  17.11(h) by adding an entry for ``Topminnow, Barrens'' 
to the List of Endangered and Threatened Wildlife in alphabetical order 
under FISHES to read as follows:

Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

                                                                                              Listing citations
            Common name                Scientific name          Where listed       Status   and applicable rules
                                                  * * * * * * *
                                                  * * * * * * *
Topminnow, Barrens................  Fundulus julisia.....  Wherever found.......        E   [Insert Federal
                                                                                             Register citation
                                                                                             when published as a
                                                                                             final rule]
                                                  * * * * * * *

     Dated: December 3, 2017.
 James W. Kurth,
Deputy Director for U.S. Fish and Wildlife Service, Exercising the 
Authority of the Director for U.S. Fish and Wildlife Service.
[FR Doc. 2017-28491 Filed 1-3-18; 8:45 am]