[Federal Register Volume 88, Number 244 (Thursday, December 21, 2023)]
[Proposed Rules]
[Pages 88338-88359]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-27873]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R4-ES-2023-0220; FF09E21000 FXES1111090FEDR 245]
RIN 1018-BG92


Endangered and Threatened Wildlife and Plants; Threatened Species 
Status for Coal Darter With Section 4(d) Rule

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list the coal darter (Percina brevicauda), a small, benthic freshwater 
fish native to the Mobile River Basin in Alabama, as a threatened 
species under the Endangered Species Act of 1973, as amended (Act). 
This determination also serves as our 12-month finding on a petition to 
list the coal darter. After a review of the best available scientific 
and commercial information, we find that listing the species is 
warranted. Accordingly, we propose to list the coal darter as a 
threatened species with a rule issued under section 4(d) of the Act 
(``4(d) rule'') to provide for the conservation of the species. If we 
finalize this rule as proposed, it would add this species to the List 
of Endangered and Threatened Wildlife and extend the Act's protections 
to the species.

DATES: We will accept comments received or postmarked on or before 
February 20, 2024. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES, below) must be received by 11:59 
p.m. eastern time on the closing date. We must receive requests for a 
public hearing, in writing, at the address shown in FOR FURTHER 
INFORMATION CONTACT by February 5, 2024.

ADDRESSES: 
    Written comments: You may submit comments by one of the following 
methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R4-ES-2023-0220, 
which is the docket number for this rulemaking. Then, click on the 
Search button. On the resulting page, in the panel on the left side of 
the screen, under the Document Type heading, check the Proposed Rule 
box to locate this document. You may submit a comment by clicking on 
``Comment.''
    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R4-ES-2023-0220, U.S. Fish and Wildlife Service, 
MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
    We request that you send comments only by the methods described 
above. We will post all comments on https://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see Information Requested, below, for more information).
    Availability of supporting materials: Supporting materials, such as 
the species status assessment report, are available on the Service's 
website at https://www.fws.gov/office/alabama-ecological-services, at 
https://ecos.fws.gov/ecp/species/9959, and at https://www.regulations.gov under Docket No. FWS-R4-ES-2023-0220.

FOR FURTHER INFORMATION CONTACT: William Pearson, Field Supervisor, 
U.S. Fish and Wildlife Service, Alabama Ecological Services Field 
Office, 1208 Main Street, Daphne, AL 36526; telephone 251-441-5181. 
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. Please see Docket No. FWS-R4-ES-2023-0220 on https://www.regulations.gov for a document that summarizes this proposed rule.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Act (16 U.S.C. 1531 et 
seq.), a species warrants listing if it meets the definition of an 
endangered species (in danger of extinction throughout all or a 
significant portion of its range) or a

[[Page 88339]]

threatened species (likely to become endangered within the foreseeable 
future throughout all or a significant portion of its range). If we 
determine that a species warrants listing, we must list the species 
promptly and designate the species' critical habitat to the maximum 
extent prudent and determinable. We have determined that the coal 
darter meets the Act's definition of a threatened species; therefore, 
we are proposing to list it as such. Listing a species as a threatened 
species can be completed only by issuing a rule through the 
Administrative Procedure Act rulemaking process (5 U.S.C. 551 et seq.).
    What this document does. We propose to list the coal darter as a 
threatened species with a rule issued under section 4(d) of the Act.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species because of any of five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that the coal darter meets the 
definition of a threatened species due to habitat loss or degradation 
from the following activities or conditions: hydrologic alteration by 
impoundments, including dams and other barriers; agriculture (poultry 
farming); urban development or change in land cover, including 
increased density of residential and commercial infrastructure; 
resource extraction, including mining and silviculture operations that 
do not follow State-approved best management practices (BMPs); 
diminished water quality from point and nonpoint source chemical 
contamination and sedimentation (Factor A); and climate change (Factor 
E).

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other governmental agencies, Native 
American Tribes, the scientific community, industry, or any other 
interested parties concerning this proposed rule. We particularly seek 
comments concerning:
    (1) The species' biology, range, and population trends, including:
    (a) Biological or ecological requirements of the species, including 
habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns 
and the locations of any additional populations of this species;
    (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) Threats and conservation actions affecting the species, 
including:
    (a) Factors that may be affecting the continued existence of the 
species, which may include habitat modification or destruction, 
overutilization, disease, predation, the inadequacy of existing 
regulatory mechanisms, or other natural or manmade factors;
    (b) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this species; and
    (c) Existing regulations or conservation actions that may be 
addressing threats to this species.
    (3) Additional information concerning the historical and current 
status of this species.
    (4) Information on regulations that may be necessary and advisable 
to provide for the conservation of the coal darter and that we can 
consider in developing a 4(d) rule for the species. In particular, we 
seek information concerning the extent to which we should include any 
of the Act's section 9 prohibitions in the 4(d) rule or whether we 
should consider any additional exceptions from the prohibitions in the 
4(d) rule.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for, or 
opposition to, the action under consideration without providing 
supporting information, although noted, do not provide substantial 
information necessary to support a determination. Section 4(b)(1)(A) of 
the Act directs that determinations as to whether any species is an 
endangered or a threatened species must be made solely on the basis of 
the best scientific and commercial data available.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in ADDRESSES.
    If you submit information via https://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the website. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on https://www.regulations.gov.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov.
    Our final determination may differ from this proposal because we 
will consider all comments we receive during the comment period as well 
as any information that may become available after this proposal. Based 
on the new information we receive (and, if relevant, any comments on 
that new information), we may conclude that the species is endangered 
instead of threatened, or we may conclude that the species does not 
warrant listing as either an endangered species or a threatened 
species. In addition, we may change the parameters of the prohibitions 
or the exceptions to those prohibitions in the 4(d) rule if we conclude 
it is appropriate in light of comments and new information received. 
For example, we may expand the prohibitions to include prohibiting 
additional activities if we conclude that those additional activities 
are not compatible with conservation of the species. Conversely, we may 
establish additional exceptions to the prohibitions in the final rule 
if we conclude that the activities would facilitate or are compatible 
with the conservation and recovery of the species. In our final rule, 
we will clearly explain our rationale and the basis for our final 
decision, including why we made changes, if any, that differ from this 
proposal.

Public Hearing

    Section 4(b)(5) of the Act provides for a public hearing on this 
proposal, if requested. Requests must be received by the date specified 
in DATES. Such requests must be sent to the address shown in FOR 
FURTHER INFORMATION CONTACT. We will schedule a public hearing on this 
proposal, if requested, and announce the date, time, and place of the 
hearing, as well as how to obtain reasonable accommodations, in the 
Federal Register and local newspapers

[[Page 88340]]

at least 15 days before the hearing. We may hold the public hearing in 
person or virtually via webinar. We will announce any public hearing on 
our website, in addition to the Federal Register. The use of virtual 
public hearings is consistent with our regulations at 50 CFR 
424.16(c)(3).

Previous Federal Actions

    On April 20, 2010, we received a petition from the Center for 
Biological Diversity (CBD), Alabama Rivers Alliance, Clinch Coalition, 
Dogwood Alliance, Gulf Restoration Network, Tennessee Forests Council, 
and West Virginia Highlands Conservancy to list 404 aquatic, riparian, 
and wetland species, including the coal darter, as endangered or 
threatened species under the Act. In response to the petition, we 
published a partial 90-day finding on September 27, 2011 (76 FR 59836), 
in which we announced our finding that the petition contained 
substantial information indicating that listing may be warranted for 
numerous species, including the coal darter.

Peer Review

    A species status assessment (SSA) team prepared an SSA report for 
the coal darter. The SSA team was composed of Service biologists, in 
consultation with other species experts. The SSA report represents a 
compilation of the best scientific and commercial data available 
concerning the status of the species, including the impacts of past, 
present, and future factors (both negative and beneficial) affecting 
the species.
    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 
2016, memorandum updating and clarifying the role of peer review in 
listing actions under the Act, we solicited independent scientific 
review of the information contained in the coal darter SSA report. We 
sent the SSA report to five independent peer reviewers and received one 
response. Results of this structured peer review process can be found 
at https://www.regulations.gov. In preparing this proposed rule, we 
incorporated the results of these reviews, as appropriate, into the SSA 
report, which is the foundation for this proposed rule.

Summary of Peer Reviewer Comments

    As discussed in Peer Review, above, we received comments from one 
peer reviewer on the draft SSA report. We reviewed the comment for 
substantive issues and new information regarding the information 
contained in the SSA report. The peer reviewer generally provided 
constructive suggestions and was broadly supportive. No substantive 
changes to our analysis and conclusions within the SSA report were 
deemed necessary, and peer reviewer comments are addressed in version 
1.1 of the SSA report.

I. Proposed Listing Determination

Background

    A thorough review of the taxonomy, life history, and ecology of the 
coal darter is presented in the SSA report (version 1.1; Service 2023, 
pp. 11-15).
    The coal darter (Percina brevicauda) is a small, benthic freshwater 
fish native to the Mobile River Basin in Alabama. The species occurs in 
small to medium-sized rivers and the larger tributaries of those rivers 
with moderate to swift flowing water. It has been observed in riffle 
and run habitat, as well as in glide and pool habitat with stable sand, 
gravel, cobble, and bedrock substrates with low levels of siltation. 
The coal darter is a member of the genus Percina in the family Percidae 
(perches), and was originally described as the channel darter, first as 
Etheostoma copelandi (Gilbert 1891) and subsequently, as Percina 
copelandi (Moore 1957) when the channel darter was reclassified into 
the genus Percina. In 1994, the coal darter was described as a unique 
species, named Percina brevicauda, and placed with two other species 
recognized within the subgenus Cottogaster (the channel darter (Percina 
copelandi) and the pearl darter (Percina aurora)) (Suttkus and Bart 
1994). Genetic analyses provided strong support of Cottogaster being a 
monophyletic clade, with these three species being sister clades.
    The coal darter is a small, elongated, slightly compressed 
freshwater fish reaching up to 50 millimeters (mm) (1.96 inches (in)) 
in total length with smaller fins compared to other Cottogaster 
members. It has dark lateral blotches and a continuous lateral stripe 
pattern on the body. Nuptial males are heavily pigmented, including on 
the ventral surface of the head and body, giving them a dusky 
appearance, which is the reason for the common name, coal darter. They 
are diurnal feeders and consume aquatic invertebrates (insects, 
crustaceans, worms). Little is known about the specific life-history 
characteristics of the coal darter. Most of the life-history knowledge 
for the species is inferred from information known for the channel 
darter and pearl darter.
    The coal darter is endemic to the eastern and central part of the 
Mobile River Basin in the State of Alabama. The species primarily 
occupies habitat above the Fall Line within the Piedmont, Ridge and 
Valley, and Southwestern Appalachians level III ecoregions. 
Additionally, there are several historical records below the Fall Line 
in the Cahaba River and Black Warrior River that are in the 
Southeastern Plains ecoregion.
    Presently, the species has a disjunct distribution, with 
populations in the Cahaba River, the Locust Fork of the Black Warrior 
River, and two tributaries in the lower Coosa River (Weogufka Creek and 
Hatchet Creek). Within the Locust Fork watershed, occurrences are 
mostly in the Locust Fork mainstem, but there are also occurrences in 
Turkey Creek, the Little Warrior River, and Blackburn Fork. In the 
Cahaba River system, the coal darter is predominantly found in the 
mainstem of the Cahaba River with occurrences in Shades Creek and the 
Little Cahaba River.

Regulatory and Analytical Framework

Regulatory Framework

    Section 4 of the Act (16 U.S.C. 1533) and the implementing 
regulations in title 50 of the Code of Federal Regulations set forth 
the procedures for determining whether a species is an endangered 
species or a threatened species, issuing protective regulations for 
threatened species, and designating critical habitat for endangered and 
threatened species. In 2019, jointly with the National Marine Fisheries 
Service, the Service issued a final rule that revised the regulations 
in 50 CFR part 424 regarding how we add, remove, and reclassify 
endangered and threatened species and the criteria for designating 
listed species' critical habitat (84 FR 45020; August 27, 2019). On the 
same day, the Service also issued final regulations that, for species 
listed as threatened species after September 26, 2019, eliminated the 
Service's general protective regulations automatically applying to 
threatened species the prohibitions that section 9 of the Act applies 
to endangered species (84 FR 44753; August 27, 2019). Our analysis for 
this decision applied the regulations that are currently in effect, 
which include the 2019 revisions. However, we proposed further 
revisions to these regulations on June 22, 2023 (88 FR 40764). In case 
those revisions are finalized before we make a final status 
determination for this species, we have also undertaken an analysis of 
whether the decision would be different if we were to apply those 
proposed revisions. We concluded that the decision would have been the 
same if we had applied the proposed 2023 regulations. The

[[Page 88341]]

analyses under both the regulations currently in effect and the 
regulations after incorporating the June 22, 2023, proposed revisions 
are included in our decision file.
    The Act defines an ``endangered species'' as a species that is in 
danger of extinction throughout all or a significant portion of its 
range, and a ``threatened species'' as a species that is likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether any species is an endangered species or a threatened 
species because of any of the following factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    These factors represent broad categories of natural or human-caused 
actions or conditions that could have an effect on a species' continued 
existence. In evaluating these actions and conditions, we look for 
those that may have a negative effect on individuals of the species, as 
well as other actions or conditions that may ameliorate any negative 
effects or may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). The term ``threat'' 
may encompass--either together or separately--the source of the action 
or condition or the action or condition itself.
    However, the mere identification of any threat(s) does not 
necessarily mean that the species meets the statutory definition of an 
``endangered species'' or a ``threatened species.'' In determining 
whether a species meets either definition, we must evaluate all 
identified threats by considering the 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 Act's definition of an ``endangered species'' or 
a ``threatened species'' only after conducting this cumulative analysis 
and describing the expected effect on the species now and in the 
foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as we can 
reasonably determine that both the future threats and the species' 
responses to those threats are likely. In other words, the foreseeable 
future is the period of time in which we can make reliable predictions. 
``Reliable'' does not mean ``certain''; it means sufficient to provide 
a reasonable degree of confidence in the prediction. Thus, a prediction 
is reliable if it is reasonable to depend on it when making decisions.
    It is not always possible or necessary to define the foreseeable 
future as a particular number of years. Analysis of the foreseeable 
future uses the best scientific and commercial data available and 
should consider the timeframes applicable to the relevant threats and 
to the species' likely responses to those threats in view of its life-
history characteristics. Data that are typically relevant to assessing 
the species' biological response include species-specific factors such 
as lifespan, reproductive rates or productivity, certain behaviors, and 
other demographic factors.

Analytical Framework

    The SSA report documents the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of the species, including an assessment of the potential 
threats to the species. The SSA report does not represent our decision 
on whether the species should be proposed for listing as an endangered 
or threatened species under the Act. However, it does provide the 
scientific basis that informs our regulatory decisions, which involve 
the further application of standards within the Act and its 
implementing regulations and policies.
    To assess the coal darter's viability, we used the three 
conservation biology principles of resiliency, redundancy, and 
representation (Shaffer and Stein 2000, pp. 306-310). Briefly, 
resiliency is the ability of the species to withstand environmental and 
demographic stochasticity (for example, wet or dry, warm or cold 
years); redundancy is the ability of the species to withstand 
catastrophic events (for example, droughts, large pollution events); 
and representation is the ability of the species to adapt to both near-
term and long-term changes in its physical and biological environment 
(for example, climate conditions, pathogens). In general, species 
viability will increase with increases in resiliency, redundancy, and 
representation (Smith et al. 2018, p. 306). Using these principles, we 
identified the species' ecological requirements for survival and 
reproduction at the individual, population, and species levels, and 
described the beneficial and risk factors influencing the species' 
viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the individual species' life-
history needs. The next stage involved an assessment of the historical 
and current condition of the species' demographics and habitat 
characteristics, including an explanation of how the species arrived at 
its current condition. The final stage of the SSA involved making 
predictions about the species' responses to positive and negative 
environmental and anthropogenic influences. Throughout all of these 
stages, we used the best available information to characterize 
viability as the ability of a species to sustain populations in the 
wild over time. We use this information to inform our regulatory 
decision.
    The following is a summary of the key results and conclusions from 
the SSA report; the full SSA report can be found at Docket No. FWS-R4-
ES-2023-0220 on https://www.regulations.gov and at https://ecos.fws.gov/ecp/species/9959.

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
species and its resources, and the threats that influence the species' 
current and future condition, in order to assess the species' overall 
viability and the risks to that viability.

Individual, Population, and Species Needs

    A thorough review of the coal darter's resource needs is presented 
in chapter

[[Page 88342]]

3 of the SSA report (version 1.1; Service 2023, pp. 17-18).
    For the coal darter to survive and reproduce, individuals need 
suitable habitat that supports essential life functions at all life 
stages (see table 1, below). Four elements appear to be essential to 
the survival and reproduction of individuals: sufficient water quality, 
flowing water, stable substrates, and habitat heterogeneity.
    For coal darter populations to be resilient, the needs of 
individuals require sufficient water quality, flowing water, stable 
substrates, and habitat heterogeneity to be met on a larger scale (see 
table 1, below). Stream reaches with suitable habitat must be large 
enough to support a sufficient reservoir of potential mates for coal 
darters to breed with and maintain sufficient genetic health while 
avoiding issues associated with small population sizes, such as genetic 
drift and inbreeding depression.
    Connectivity is also an important factor for populations because it 
facilitates genetic health for populations and enables movement of 
individuals to suitable habitats that can accommodate the life-history 
needs for the species (i.e., spawning, refuge, feeding). Natural flow 
regimes are an important resource need for coal darter populations, as 
flows may help trigger spawning and are a habitat requirement for all 
life stages.
    At the species level, the coal darter needs a sufficient number and 
distribution of healthy populations to withstand environmental 
stochasticity (resiliency) and catastrophes (redundancy), and to adapt 
to biological and physical changes in its environment (representation). 
For the species to be viable, there must be adequate redundancy 
(suitable number, distribution, and connectivity of populations to 
allow the species to withstand catastrophic events) and representation 
(genetic and environmental diversity to allow the species to adapt to 
changing environmental conditions). Redundancy improves with increasing 
numbers of resilient populations distributed across the species' range, 
and connectivity (either natural or human-facilitated) allows connected 
populations to ``rescue'' each other after catastrophes. Representation 
improves with the persistence of populations having greater genetic and 
ecological diversity across the species' range, resulting in an 
increased ability to adapt to changing environmental conditions. Long-
term viability will require resilient populations; for the coal darter, 
this will mean maintaining quality stream habitat (for example, 
sufficient water quality, natural flow regime, stable substrate, and 
adequate habitat heterogeneity) to support multiple populations across 
the species' range (see table 1, below).

 Table 1--Summary of Coal Darter Individual Resource Needs by Life Stage
------------------------------------------------------------------------
            Life stage                        Resources needed
------------------------------------------------------------------------
Eggs..............................  <bullet> Suitable gravel/cobble
                                     substrate for egg deposition.
                                    <bullet> Low amounts of silt and
                                     fine sediment.
                                    <bullet> Suitable water quality and
                                     quantity.
Larvae............................  <bullet> Connectivity to suitable
                                     habitat for dispersal.
                                    <bullet> Sufficient water flow for
                                     dispersal.
Juveniles.........................  <bullet> Sufficient gravel/cobble/
                                     boulder substrate.
                                    <bullet> Aquatic invertebrate food
                                     source.
                                    <bullet> Sufficient water flow.
                                    <bullet> Presence of habitat
                                     heterogeneity (riffles, runs,
                                     pools).
                                    <bullet> Suitable water quality and
                                     quantity.
Adults............................  <bullet> Sufficient gravel/cobble
                                     substrate.
                                    <bullet> Sufficient structural
                                     habitat (rock, aquatic vegetation).
                                    <bullet> Aquatic invertebrate food
                                     source.
                                    <bullet> Sufficient water flow.
                                    <bullet> Presence of habitat
                                     heterogeneity (riffles, runs,
                                     pools).
                                    <bullet> Sufficient water quality
                                     and quantity.
------------------------------------------------------------------------

    At the species level, the coal darter requires sufficient 
connectivity between populations to facilitate gene flow and ensure 
adaptive potential. Genetic diversity should be high enough that the 
species will be able to adapt to changing environmental factors through 
the process of natural selection. Additionally, the species needs to 
have sufficient connectivity between enough individuals to promote an 
effective population size that is high enough to maintain evolutionary 
potential and genetic adaptive capacity. To evaluate the current and 
future viability of the coal darter, we assessed a range of conditions 
to allow us to consider the species' resiliency, representation, and 
redundancy.

Threats

    A thorough review of the threats affecting the coal darter is 
presented in chapter 4 of the SSA report (version 1.1, Service 2023, 
pp. 23-31).
    The coal darter is influenced by stressors affecting water quality, 
water flow, stream connectivity, and genetic diversity. The main threat 
is habitat loss or degradation from the following activities or 
conditions: hydrologic alteration by impoundments, including dams and 
other barriers; agriculture (poultry farming); diminished water quality 
from point and nonpoint source chemical contamination and 
sedimentation; urban development or change in land cover, including 
increased density of residential and commercial infrastructure; 
resource extraction, including mining and silviculture operations that 
do not follow State-approved BMPs; and climate change (Service 2023, p. 
23).
Impoundments
    Impoundment of rivers is a primary threat to aquatic species in the 
Southeast (Service 2023, pp. 23-24). Dams modify habitat conditions and 
aquatic communities both upstream and downstream of an impoundment. 
Upstream of dams, habitat is flooded and in-channel conditions change 
from flowing to still water, with increased depth, decreased levels of 
dissolved oxygen, and increased sedimentation. Downstream of dams, flow 
regimes of the released tailwater vary with resulting fluctuations in 
water temperature and dissolved oxygen levels, the substrate is 
scoured, and downstream reaches are eroded. These negative tailwater 
effects on habitat can extend many kilometers downstream. Dams fragment 
habitat for the coal darter by blocking corridors for

[[Page 88343]]

migration and dispersal, resulting in population isolation and 
increased risk of extirpation and extinction. All known populations of 
the coal darter are separated from each other by large dams. The 
virtually complete loss of the Coosa population and approximately 50 
percent loss of the Black Warrior population are attributed to the 
construction of dams, reservoir creation, and channelization that 
occurred in these systems in the late 1800s to mid-1900s (see table 2, 
below). Impoundments in the Black Warrior River system were created to 
transport goods between Mobile and Tuscaloosa, and ultimately 
Birmingham. Construction of these impoundments included removal and 
clearing of overhanging trees and vegetation, blasting of rock and 
shoal complexes, removal of submerged woody debris and logs, and 
modification or removal of sand and gravel bars (Mettee 2019, pp. 10-
22). Impoundments in the Coosa River Systems for hydroelectric power 
production were constructed by Alabama Power between the 1920s and 
1960s. These impoundments are still in place today and significantly 
reduced the amount of available habitat for coal darters in the Coosa 
and Black Warrior River systems (Table 2).

Table 2--Comparison of Historically Occupied River Lengths and Currently
   Occupied River Lengths of Coal Darters in Three Major River Systems
                          [Service 2023, p. 14]
------------------------------------------------------------------------
                                     Historically
          River systems                occupied        Currently occupy
------------------------------------------------------------------------
Black Warrior...................  At least 130 river  65 rmi/104.7 rkm.
                                   miles (rmi)/209.2
                                   river kilometers
                                   (rkm).
Cahaba..........................  133 rmi/214 rkm...  114.9 rmi/184.9
                                                       rkm.
Coosa...........................  At least 92.2 rmi/  9 rmi/14.5 rkm in
                                   148.4 rkm.          Hatchet Creek,
                                                       one site in
                                                       Weogufka Creek.
------------------------------------------------------------------------

    The Cahaba River, at 190 rmi/305.8 rkm long, is often referred to 
as Alabama's longest free-flowing stream. However, two barriers have 
impacted the flow of the river. The first is a low-head dam, located at 
Highway 280 near Acton, Alabama, and built in 1891. It is 15 feet tall 
and backs up water for withdrawal by Birmingham. This low-head dam is 
significantly smaller than the dams on the Black Warrior River and 
Coosa River, and as such, the Highway 280 dam has not converted vast 
areas of habitat, meaning habitat for the coal darter is still present 
and the species is still able to occupy habitat both upstream and 
downstream of the dam. Although coal darters occur upstream and 
downstream of the Highway 280 dam, this dam represents a significant 
barrier to upstream movement of coal darters. Downstream dispersal 
could be possible when larvae enter the water column and are carried 
downstream during a process known as pelagic larval drift (PLD). 
Because individuals upstream of the dam are isolated from those 
downstream, the upstream subpopulation is at a higher risk of genetic 
drift and inbreeding depression. The second barrier, the Marvel Slab, 
was removed in 2004; it is discussed in more detail under Conservation 
Efforts and Regulatory Mechanisms, below.
Water Quality
    In general, darters tend to be sensitive to poor water quality 
(Service 2023, pp. 24-26). According to the Fishery Index Biotic 
Integrity (IBI) reports and related fish community survey work, coal 
darters are consistently labeled as a ``disturbance-sensitive'' or an 
``intolerant'' (of habitat impairments) species. Based on its narrow 
distribution and habitat conditions (including water quality 
parameters) where coal darters are found, the coal darter needs clean, 
relatively clear, flowing water to survive and carry out its basic 
life-history functions; thus, water quality degradation is considered a 
threat to the species. Below, we discuss the causes of water quality 
degradation in more detail.
    Point and Nonpoint Source Pollution--Inputs of point source 
pollution (discharge from an identifiable source) and nonpoint source 
pollution (diffuse land surface runoff) across the coal darter's range 
are numerous and widespread. Point source pollution originates from 
inadequately treated effluent from industrial plants, sanitary 
landfills, sewage treatment plants, active surface mining, drain fields 
from individual private homes, and others.
    Nonpoint source pollution may originate from agricultural 
activities, poultry and cattle feedlots, abandoned mine runoff, 
construction, silviculture operations that do not follow State-approved 
BMPs, failing septic tanks, and contaminated runoff from urban areas. 
These sources have the potential to contribute pollution, including 
sediments, heavy metals, fertilizers, pesticides (e.g., herbicides, 
insecticides, fungicides, and rodenticides), animal wastes, septic tank 
and gray water leakage, and oils and greases, to streams. Water quality 
declines resulting from this pollution cause nitrification, decreases 
in dissolved oxygen (DO) concentration, increases in acidity and 
conductivity, and introduction of toxicants. These alterations likely 
have direct (decreased survival and/or reproduction) and indirect 
(loss, degradation, and fragmentation of habitat) effects on coal 
darters. For the coal darter, submerged vegetation provides spawning 
habitat for adults, refugia from predators, and habitat for prey of all 
life stages. Aquatic vegetation also provides substrate stability for 
the species. Degraded water quality and high algal biomass that result 
from pollutant inputs cause loss of these critical submerged plant 
species (e.g., water willow (Justicia americana), river weed 
(Podostemum ceratophyllum)), which are vital habitat for the coal 
darter and its prey.
    Sedimentation--Sedimentation has been linked to changes in fish 
assemblages and community structure (Shepard et al. 1994; Onorato et 
al. 2000, pp. 56-58). A wide range of current activities and land uses 
can lead to excessive sedimentation within streams, which has occurred 
throughout the coal darter's range, especially in Hatchet Creek. 
Sources potentially include agricultural practices, construction 
activities, stormwater runoff, unpaved roads, silvicultural activities, 
utility crossings, and mining. Fine sediments are not only introduced 
into streams during present day activities, but historical land-use 
practices may have substantially altered hydrological and 
geomorphological processes such that sediments continued to be input 
into streams for several decades after those activities ceased.
    Increases in sedimentation from sources such as agriculture, 
silviculture operations that do not follow State-approved BMPs, mining, 
and

[[Page 88344]]

urbanization are of concern for the coal darter and can negatively 
affect the species by reducing growth rates, disease tolerance, and 
gill function; reducing spawning habitat, reproductive success, and egg 
(embryo), larva, and juvenile development; reducing food availability 
through reductions in prey; reducing foraging efficiency; and reducing 
shelter (Service 2023, pp. 25-26).
Agriculture
    Agricultural practices such as traditional farming, feedlot 
operations, and associated land-use practices can contribute pollutants 
to rivers. These practices can also degrade habitat by encouraging the 
erosion of stream banks, which results in alterations to stream 
hydrology and geomorphology. Nutrients, bacteria, pesticides, and other 
organic compounds are generally found in higher concentrations in areas 
around agriculture than in forested areas. Contaminants associated with 
agriculture (fertilizers, pesticides, herbicides, and animal waste) can 
cause degradation of water quality and habitats through instream oxygen 
deficiencies, excess nutrification, and excessive algal growths, with a 
related alteration in fish community composition. In the Alabama 
Department of Environmental Management's (ADEM's) 2022 list of impaired 
waters, which was prepared in accordance with section 303(d) of the 
Clean Water Act (CWA; 33 U.S.C. 1251 et seq.) and submitted to the 
Environmental Protection Agency (EPA), Hatchet Creek was designated as 
impaired due the presence of pathogens from animal feeding operations 
and pasture grazing, and Weogufka Creek was designated as impaired due 
to the presence of pathogens from pasture grazing (ADEM 2022, p. 300).
    Poultry farming, undertaken primarily in poultry houses, occurs 
within the range of the coal darter, especially in and around the 
Locust Fork watershed. Poultry houses have an estimated ability to 
produce approximately 100 tons of litter a year (assuming a 20,000-
square-foot poultry house stocked at one bird per square foot and six 
flocks produced per year, which is a probable underestimate of litter 
production per broiler house). Poultry litter is a mixture of chicken 
manure, feathers, spilled food, and bedding material that is used to 
fertilize pastureland or row crops that frequently occur adjacent to 
rivers and streams.
    Runoff from heavy rains carries excess nutrients from chicken 
manure into nearby streams as a result of surface-spreading of litter. 
Litter can also contain arsenic, which is formed from a chemical 
routinely used as a feed additive to prevent disease and stimulate 
growth, and it enters streams through runoff (Stolze et al. 2007, p. 
821). Other substances often found in poultry litter include fecal 
coliform, Salmonella, and other pathogens; pesticide residue; and other 
heavy metals (Bolan et al. 2010, pp. 676-683). In general, the inputs 
from poultry litter into rivers and streams reduce water quality for 
the coal darter, causing physiological stress. This is especially 
evident in Locust Fork in the species' range (ADEM 1999, pp. 57-78, 
147, 218; Deutsch et al. 1990, entire).
Resource Extraction: Mining and Oil/Gas
    Coal mining in Alabama began in the early 1800s. Currently, there 
are active and reclaimed mines operating throughout the Black Warrior 
and Cahaba watersheds, and one proposed graphite mine permitted for 
future operations in the Coosa watershed. Surface and subsurface coal 
mines have the potential to degrade water quality from erosion and 
sedimentation, and the presence of mines near rivers and streams 
elevates the risk of water contamination. These mining processes expose 
metallic minerals, which can then enter the surrounding waterways, 
increasing conductivity, increasing acidity, and contaminating the 
waterways with heavy metals, creating toxic conditions for aquatic 
fauna (Stiefel and Busch 1983, pp. 187-212; Neves et al. 1997, pp. 69-
70).
    In addition to surface and subsurface mining, oil and gasoline 
extraction and transportation is also present within the range of the 
coal darter. In 2016, there was a near disaster in the range of the 
coal darter when 252,000 gallons of gasoline spilled from the Colonial 
Pipeline into an old mining pond that feeds into a tributary of the 
Cahaba (EPA 2016, unpaginated). The spill was contained before reaching 
the Cahaba River; however, this incident illustrates that the risk of 
threat to the species from resource extraction does exist.
Resource Extraction: Silviculture
    The forestry industry, in the form of monoculture pine plantations, 
is prevalent throughout the range of the coal darter. Forestry can have 
negative implications for water quality in the form of nonpoint source 
pollution, especially when BMPs are not implemented. Excessive 
sedimentation in Hatchet Creek has been documented since the mid-1990s. 
The excessive sedimentation and subsequent loss of clean gravel and 
pool habitat has been attributed to forestry activities, including 
removal of riparian vegetation (Alabama Department of Conservation and 
Natural Resources (ADCNR) 2006, p. 3). Sedimentation of streams and 
waterways has the potential to increase due to accelerated erosion from 
logging roads and timber harvest. We recognize that modern 
silvicultural operations are widely implemented in accordance with 
State-approved BMPs, and the adherence to these BMPs broadly protects 
water quality, particularly related to sedimentation. However, in many 
cases, sedimentation in streams is a continuing legacy effect from past 
eras of poor logging practices (Service 2023, p. 27).
Urbanization
    Urbanization is a significant source of water quality degradation 
that can reduce the survival of aquatic organisms, including the coal 
darter. Urbanization refers to a change in land cover and land use from 
forests or agriculture to increased density of residential and 
commercial infrastructure. Urban development can stress aquatic systems 
in a variety of ways, including increasing the frequency and magnitude 
of high flows in streams, increasing sedimentation (construction 
activities) and nutrient loads (lawn fertilization), increasing 
contamination and toxicity (from household pesticides and herbicides), 
altering flows because of an increase in impervious surfaces (i.e., 
flashier flows), and altering stream morphology, stability, and 
chemistry, which can result in a decreased diversity of fishes, aquatic 
insects, plants, and amphibians. Sources and risks of an acute or 
catastrophic contamination event, such as a leak from an underground 
storage tank, pipeline, or wastewater system, or a hazardous materials 
spill on a highway, also increase as urbanization increases.
    Changes to both frequency and magnitude of stream flows have direct 
effects on important structural habitat for coal darters. Stream 
channelization and higher flows reduce overall stream cover and other 
natural substrates like boulders, cobble, and gravel, and they remove 
large woody structures and other terrestrial plant materials. As a 
result, urban streams have lower habitat heterogeneity, stable 
substrates, and amounts of plant material, which negatively impacts the 
coal darter's sheltering, breeding, and feeding.
    Birmingham is the third largest city in the State of Alabama and 
was ranked as the largest city until the 2020 census. It continues to 
be one of the fastest growing metropolitan areas in the State.

[[Page 88345]]

Despite the population of Birmingham decreasing between 1992 and 2011, 
urban cover over that time period increased from 9.4 percent to 35.7 
percent due to expansion of the metropolitan area (Dosdogru et al. 
2020, p. 2). The upper part of the Cahaba River watershed and the 
southeastern part of the Locust Fork watershed drain a significant 
portion of the Birmingham metropolitan area. The overall degradation of 
water and habitat quality because of increased urbanization has 
negative implications for coal darter populations currently, and into 
the future, as discussed below under Current Condition and Future 
Condition.
Climate Change
    Changing climate conditions can influence coal darter viability 
through changes in water temperature and precipitation patterns that 
result in increased flooding, prolonged droughts, or reduced stream 
flows. Since the 1970s, moderate to severe droughts in the Southeast 
have increased by 12 percent during spring months and by 14 percent 
during summer months (Jones et al. 2015, p. 126). Reduced baseflows due 
to droughts can cause population declines, habitat loss, and degraded 
water quality (decreased dissolved oxygen and temperature alteration) 
leading to death, crowding of individuals leading to stress, and 
decreased reproduction in stream fish populations. Increased 
groundwater withdrawal for agriculture or other human needs during 
droughts may potentially exacerbate the impacts of reduced quantity or 
frequency of precipitation.
    Climate models for the southeastern United States project that 
average annual temperatures will increase, cold days will become less 
frequent, the freeze-free season will lengthen by up to a month, days 
with temperatures exceeding 95 degrees Fahrenheit will increase, heat 
waves will become longer, and the number of category 5 hurricanes will 
increase (Ingram et al. 2013, p. 32; IPCC 2021, entire). While these 
climate models predict variability into the future, they suggest that 
the region will be subjected to more frequent large storms (hurricanes) 
with severe flooding and extremely low flows during droughts. Average 
and extreme precipitation is expected to increase, and subsequently, 
river flooding is also expected to increase. Extreme weather events, 
such as flash flooding associated with heavy precipitation events, are 
projected to increase in the future within the range of the coal 
darter, and these events can impact the coal darter through habitat 
degradation and displacement, injury, or even mortality (Service 2023, 
pp. 29-30).
    Future changes in climate within the coal darter's range include 
increases in temperatures, especially for summer and fall, and 
increases in overall precipitation. Therefore, the watersheds occupied 
by coal darters could experience moderate to significant changes in 
climate by the 2050s, especially under scenarios run for representative 
concentration pathway (RCP) 8.5 (corresponding to high levels of carbon 
emissions). Increases in summer temperatures coupled with decreased 
instream flow can increase water temperatures and reduce dissolved 
oxygen levels, while flashier flows can increase soil erosion and 
stream sedimentation.
Low Genetic Diversity
    Low genetic diversity makes the coal darter vulnerable to threats. 
Greater genetic diversity results in greater potential to adapt to a 
changing environment through natural selection. Reduced genetic 
diversity in a population can limit its adaptive potential. Small 
populations often have lower genetic diversity because there are fewer 
individuals. Small populations are also susceptible to genetic 
phenomena of inbreeding depression, population bottlenecks, and genetic 
drift, which can lead to a greater reduction in genetic diversity over 
time and reduced fitness of the population, leaving it more vulnerable 
to changing environmental conditions. The combination and interaction 
of these negative demographic and genetic effects on a small population 
can lead the population into an extinction vortex.
    Effective population size (Ne) goes hand in hand with genetic 
diversity. There are two heuristics relating effective population size 
to conservation biology principles. The first is the 50/500 ``rule of 
thumb,'' which states that if a population's estimated effective 
population size is greater than 500, then it will maintain evolutionary 
potential and adaptive capacity over time. However, an effective 
population size of fewer than 50 would place the population in the 
extinction vortex, and as the Ne falls below 500 and moves towards 50, 
the population becomes increasingly at risk of loss in genetic 
variation. The more conservative theory is the 100/1,000 ``rule of 
thumb,'' which states that an estimated effective population size of 
more than 1,000 is needed to maintain evolutionary potential, and an 
effective population size of fewer than 100 would place the population 
in the extinction vortex.
    In 2018 to 2020, range-wide genetic analyses were carried out for 
the coal darter, which included samples from the Cahaba River, Locust 
Fork, and Hatchet Creek. No samples were included in the analysis from 
Weogufka Creek, because individuals at that site were discovered in 
2021, after this genetic work was completed. As such, the Coosa River 
system is represented only by Hatchet Creek in the genetics analysis.
    Results show that populations were historically connected and 
shared gene flow, however they are currently functionally isolated, 
showing no gene flow between the three watersheds (Jones and Sandel 
2019, entire; Jones 2021, entire). Genetic diversity was relatively low 
across all three watersheds as indicated by the observed and expected 
heterozygosity (H<INF>o</INF> and H<INF>e</INF>) and percent 
polymorphic loci. The Hatchet Creek population's genetic diversity is 
considered very low (Jones and Sandel 2019, entire; Jones 2021, 
entire). Effective population size (N<INF>e</INF>), the number of 
breeding individuals in an idealized population that would maintain 
genetic diversity, was also reported for each of the watersheds. The 
effective population size for the Black Warrior population is 2,759 
(range of 2,158-3,823); Cahaba River population is 3,145 (range of 
2,423-4,480); and Coosa River population is 268 (range of 252-290) 
(Jones and Sandel 2019, pg. 5; Jones 2021, pg. 22). In the Coosa River, 
Hatchet Creek's effective population size is an order of magnitude 
lower than the other two populations (Jones 2021, entire).

Summary

    A summary of the threats acting on coal darter populations in each 
river system is presented below in table 3. The magnitude of each of 
these threats varies from river system to river system. Details on the 
impacts of the different threats on coal darter populations are 
provided below under Current Condition.

[[Page 88346]]



                                Table 3--Summary of Threats in Each River System
----------------------------------------------------------------------------------------------------------------
            Black Warrior                            Cahaba                                 Coosa
----------------------------------------------------------------------------------------------------------------
<bullet> Water quality degradation    <bullet> Water quality degradation    <bullet> Water quality degradation
 from:                                 from:                                 from:
<bullet> Urbanization;                <bullet> Urbanization;                <bullet> Agriculture.
<bullet> Active and reclaimed mines;  <bullet> Silviculture--legacy         <bullet> Silviculture--legacy
 and                                   effects;                              effects; and
<bullet> Agriculture (including       <bullet> Active and reclaimed mines;  <bullet> Future mining.
 poultry operations); and              and                                  <bullet> ~90% reduction in range.
<bullet> Silviculture--legacy         <bullet> Agriculture.                 <bullet> Very low genetic diversity.
 effects                              <bullet> Low genetic diversity.       <bullet> Low effective population
<bullet> ~50% reduction in range.     <bullet> Climate change.               size.
<bullet> Low genetic diversity.                                             <bullet> Climate change.
<bullet> Climate change.
----------------------------------------------------------------------------------------------------------------

Conservation Efforts and Regulatory Mechanisms

    The coal darter is not State-protected in Alabama but is included 
in the Alabama State Wildlife Action Plan (SWAP), where it is assigned 
a ``priority 2'' (``high conservation concern'') status (ADCNR 2015, 
pg. 19). There have been no captive propagation efforts for the 
species. The Geological Survey of Alabama (GSA) completed targeted 
surveys for the species in the Locust Fork in 2001, and rangewide in 
2022 in partnership with the Service. Additionally, GSA, ADEM, ADCNR, 
and other partners have conducted fish Index of Biotic Integrity (IBI) 
assessments, a fish community-based assessment of stream health, in 
waterways throughout the State, including areas within the coal 
darter's range (Service 2023, pp. 31-32).
    Priority watersheds within the range of the coal darter have been 
designated as ``strategic habitat units'' (SHUs) by the Alabama Rivers 
and Streams Network (ARSN). The SHU concept was created to prioritize 
efforts and leverage capacity among partners (government, 
nongovernmental organizations, private industry) to implement 
restoration and recovery of listed and rare aquatic species. Locust 
Fork, the Cahaba River, and Hatchet Creek have all been designated as 
SHUs. However, Weogufka Creek does not have an SHU designation.
    Habitat restoration has been one of the most influential 
conservation efforts positively affecting coal darters. Projects, such 
as stream bank stabilization and dam removal, have been completed or 
planned by State and Federal partners, nonprofit organizations, and 
private landowners. These types of restoration projects are not 
specifically targeting coal darter conservation, but they aim to 
improve the habitat quality in general for the benefit of imperiled 
aquatic species.
Cahaba
    The Cahaba River has a long history of water quality declines and 
subsequent remediation activities (Thom et al. 2013, pp. 60-62). In 
recognition of these water quality challenges, EPA and the State of 
Alabama began working on measures to improve the water quality of the 
river under the auspices of the CWA. The CWA regulates water quality 
standards for surface waters and discharges of pollutants into the 
waters of the United States. The CWA made point source discharge into 
navigable waters without a permit unlawful in 1972. The EPA has 
authority to enforce the CWA, and with that authority, has developed 
national water quality criteria recommendations for pollutants found in 
surface waters and has implemented various pollution control programs 
(i.e., wastewater standards for industry) (EPA 2021, entire).
    Stormwater runoff containing pollutants is often transported 
through municipal separate stormwater sewer systems (MS4s), which 
discharge without treatment into local waterways (Service 2023, p. 33). 
An MS4 is owned by a public entity and is designed to collect and 
convey stormwater that discharges to waters of the United States. It is 
not part of a combined sewer or a publicly owned treatment facility or 
works (EPA 2023, entire). Administered under the National Pollution 
Discharge Elimination System (NPDES) permit program, MS4 permits 
require development and implementation of a comprehensive storm water 
management program (SWMP) that addresses prevention, treatment, 
removal, monitoring, and other measures to control the quality of 
stormwater that travels through storm drains to waters of the United 
States (EPA 2021, introduction). At present, several urban areas in the 
Upper Cahaba are designated as part of the MS4 program. These permits 
are regulated under the NPDES system, are treated as point sources by 
the EPA, and receive waste load allocations (WLAs) under the total 
maximum daily load (TMDL) program, which is a calculation of the 
maximum amount of a particular pollutant that can enter a water body 
and allow that water body to meet water quality standards (Service 
2023, p. 34). Thereby, under the CWA, point source discharges of 
pollutants (including stormwater) are currently being regulated.
    In addition, there are processes in place to manage new discharges 
into the river from industrial sources (e.g., industrial plants, 
mining, and wastewater). Water quality has substantially improved in 
recent decades due in part to the NPDES and the NPDES MS4 permits in 
the upper watershed, the TMDL program, and a general trend towards 
better stormwater management and soil retention measures in the 
watershed. TMDLs establish pollution reduction targets, allocate load 
reductions for pollutant sources, and include a margin of safety while 
also accounting for seasonal variability of water quality. Currently, 
the TMDL for Buck Creek, Cahaba Valley Creek, and the Cahaba River 
adhere to ADEM's water quality standards for the designated use 
classification of that stream. Overall, this has improved turbidity and 
improved nutrient loading near the coal darter population (Service 
2023, pp. 34-35).
    Significant habitat restoration efforts have also taken place in 
the Cahaba River. For example, in 2004, The Nature Conservancy, the 
U.S. Army Corps of Engineers, and other partners removed a vented ford 
dam named the Marvel Slab. Built in the 1960s and 1970s, the dam was 
originally used for transporting coal and timber across the river. It 
was 67 meters (219 feet) long, 1.8 meters (5.9 feet) tall, and 7.6 
meters (24.9 feet) wide with 40 culverts through which water could 
flow. Ecologically, the barrier functioned as a dam, blocking upstream 
movement of aquatic fauna. Removal of the structure restored 
connectivity between the river reaches. When compared with historical 
records, fish monitoring conducted after the dam was removed indicated 
that several fish species, including two that are Federally listed 
under the Act, have extended their ranges as a result of the removal 
(Bennett et al. 2015, pp. 51-61).

[[Page 88347]]

Black Warrior
    Currently, within the Black Warrior River system, the coal darter 
is restricted to the Locust Fork. The Locust Fork has its own history 
of water quality issues and remediation. In 1998, it was added to the 
EPA's list of impaired and threatened waters in Alabama (i.e., 
Alabama's 303(d) list) due to siltation and nutrient loading concerns 
along with the presence of federally endangered and threatened species. 
The ADEM performed monitoring of four 303(d) segments between 2012 and 
2016 by assessing the macroinvertebrate community and habitat quality, 
and evaluating water quality data (Service 2023, pp. 35-36).
    From these assessments, the macroinvertebrate community was 
characterized as ``fair'' for each of the four segments; habitat 
quality was ``optimal'' at the most upstream segment, ``sub-optimal'' 
at the middle two segments, and ``marginal'' at the most downstream 
segment; and the numerical water quality parameters (total suspended 
solids and turbidity) were below the eco-reference guidelines for all 
four segments (ADEM 2018, pp. 14-16). Based on these monitoring 
results, in 2018, the Locust Fork was removed from the 303(d) list for 
siltation, and it was also removed from the 303(d) list for nutrients 
because a TMDL was established (Service 2023, p. 36).

Synergistic and Cumulative Effects

    We note that, by using the SSA framework to guide our analysis of 
the scientific information documented in the SSA report, we have not 
only analyzed individual effects on the species, but we have also 
analyzed their potential cumulative effects. We incorporate the 
cumulative effects into our SSA analysis when we characterize the 
current and future conditions of the species. Our assessment of the 
current and future conditions encompasses and incorporates the threats 
individually and primary threats cumulatively. Our current and future 
conditions assessment is iterative because it accumulates and evaluates 
the effects of all the factors that may be influencing the species, 
including threats and conservation efforts. Because the SSA framework 
considers not just the presence of the factors, but to what degree they 
collectively influence risk to the entire species, our assessment 
integrates the cumulative effects of the factors and replaces a 
standalone cumulative effects analysis.

Current Condition

    A thorough review of the coal darter's current condition is 
presented in chapter 5 of the SSA report (version 1.1, Service 2023, 
pp. 39-53).
    Currently, the coal darter is known from three tributary systems of 
the Mobile River Basin: Locust Fork of the Black Warrior River, Cahaba 
River, and Hatchet and Weogufka Creeks of the Coosa River. Coal darter 
movements and dispersal patterns within these systems are not well 
understood. Recent population genetics work by University of West 
Alabama supports gene flow within each river system. However, migration 
rate estimates indicate no individuals migrating between river systems; 
thus, no contemporary gene flow exists between systems. These results 
indicate that each river system is demographically independent of each 
other. Using these data, populations were delineated based on river 
system, resulting in three populations that will serve as the 
resiliency units for assessing population resiliency: the Black 
Warrior, the Cahaba, and the Coosa. Currently, each population is found 
in a different Level III ecoregion. Since no other biologically 
meaningful boundaries are known to exist for the coal darter, we 
determined the representative units to be the same as the resiliency 
units (populations).
    Based on the coal darter's individual and population needs, such as 
adequate water quality and quantity, the availability of clean gravel/
cobble substrates, sufficient food sources, and appropriate population 
size and connectivity to support reproduction and recruitment within a 
population, we developed an approach using key habitat and demographic 
factors to assess population resiliency. We assessed two demographic 
condition parameters (genetic health and persistence through time) and 
two habitat condition parameters (Human Disturbance Gradient Index and 
habitat quantity) (see table 4, below). Based on the coal darter's 
lifespan, we used the time period from 2007 to 2022 to inform the 
current condition of the species.
    For a population to be resilient in the context of genetic health, 
a population should have sufficient standing genetic variation and 
effective population size (Ne). The 50/500 and 100/1,000 ``rules of 
thumb'' threshold were used to describe the minimum effective 
population size needed for both short-term and long-term viability. 
Greater genetic diversity in a population will improve the fitness of a 
population, equating to higher survival and rebound potential in the 
face of demographic and environmental stochasticity. An Ne greater than 
50 or 100 is necessary to prevent the deleterious effects of inbreeding 
depression and genetic drift (i.e., short-term viability) (Service 
2023, p. 41). The upper thresholds of the Ne ``rule of thumb'' (500 or 
1,000) will be important for our current condition representation 
because above this upper threshold, a population is expected to be able 
to maintain its adaptive capacity (i.e., long-term viability). However, 
the upper threshold of 500 or 1,000 is important to consider for 
resiliency as well, because when the Ne declines from 500 to 50, or 
from 1,000 to 100, the risks of genetic diversity loss progressively 
increase. Thus, an Ne below the upper thresholds of 500 or 1,000 are of 
concern for both population resiliency and species representation.
    We consider a population with high resiliency to have high or 
moderate genetic diversity and an Ne that exceeds the 500/1,000 
threshold. Thresholds for genetic diversity could not be quantified in 
table 4, below, because the genetic data we have available represent a 
snapshot of the current condition, and we do not have historical 
genetic data to which we can compare them. What is considered high, 
moderate, and low genetic diversity can vary from taxa to taxa. 
However, after consulting with conservation genetics experts on the 
coal darter's genetics and the scientific literature on genetic 
diversity results of other similar species, we determined that the 
Cahaba and Black Warrior populations exhibit ``low'' genetic diversity 
and the Hatchet Creek population exhibits ``very low'' genetic 
diversity. We used these expert opinions along with the Ne 500/1,000 
``rules of thumb'' to differentiate our ranking of moderate resiliency 
and low resiliency (Service 2023, pp. 41-42). We used research by 
University of West Alabama, which provided range-wide genetic diversity 
metrics and effective population size estimates for coal darter, in our 
assessment of current genetic health.
    When determining the current condition of the coal darter, the 
extent of the current range in the context of the historical range was 
important to consider (see table 4, below). Impoundments constructed in 
the Black Warrior and Coosa Rivers in the late 1800s to the mid-1900s, 
converted mainstem areas once occupied by coal darters to unsuitable 
conditions, resulting in large-scale extirpation throughout the 
species' historical range. This was an important consideration for the 
species because coal darters are now restricted to smaller areas than 
they were previously, which has

[[Page 88348]]

implications for maximum attainable population size, access to suitable 
habitat, and the overall ability to move and disperse when conditions 
are unfavorable at certain locations, all of which are important needs 
of the species in order to successfully reproduce and maintain 
populations (Service 2023, p. 42).
    To better assess coal darter resiliency, thresholds were 
standardized for each population by using a percentage of historical 
range in each river system to represent potential habitat for the 
species (see table 4, below). We determined that a population with high 
resiliency would have lost no more than one third of its historical 
range; a population with moderate resiliency would have lost between 
one third and two thirds of its historical range; and a population with 
low resiliency would have lost more than two thirds of its historical 
range.
    The coal darter's sensitivity to habitat alterations from human 
activities were also used to assess resiliency. In order to describe 
the level of impairment and risk to natural aquatic habitats that arise 
from human activities, the Human Disturbance Gradient Index (HDGI) was 
used (see table 4, below). The HDGI considers a variety of landscape 
variables associated with disturbance to aquatic environments. 
Specifically, these variables include: human density (population count/
kilometer of watershed), phosphorus load (kilograms/hectare/year), 
percent developed (percentage of the watershed that is developed), 
percent barren (percentage of the watershed that is barren due to human 
activities), percent pasture (percentage of the watershed that is 
pasture), percent crop (percentage of watershed that is used for row 
crops), road density (kilometers of roads/square kilometer of 
watershed), and road-stream crossings (number of road-stream crossings 
per kilometer of road). Each landscape variable is weighted by a factor 
known as the landscape development intensity (LDI) index, which ranges 
between 0 and 10, and relates land-use classifications with the 
intensity of nonrenewable energy consumption. An LDI of 0 corresponds 
to natural environments, and an LDI of 10 corresponds to highly 
developed urban environments. The sum of the weighted landscape 
variables calculated for each hydrologic unit code (HUC) 12 watershed 
in the range equates to the HDGI (Service 2023, pp. 42-43).
    The final HDGI for each population of the coal darter was found by 
averaging the HDGI of its constituent HUC 12 watersheds. Stream reaches 
with HDGI values that exceed 200 were found to correspond to poor 
biological condition with low diversity of fish species, mostly 
inhabited by generalist species tolerant of habitat uneasiness (Service 
2023, p. 43). Therefore, we expect the abundance and probability of 
coal darter presence to decline when HDGI scores approach and exceed 
200. However, we acknowledge that landscape heterogeneity within the 
scale of a HUC 12 watershed may allow suitable environmental conditions 
to persist within an otherwise largely disturbed landscape. Further, 
based on our analysis, we are most confident that HDGI scores below 175 
reflect good conditions and those above 300 reflect poor conditions. 
For these reasons, HDGI scores below 175 were classified as high 
condition or most suitable for the coal darter, with high probability 
of occurrence and high abundance; scores between 176 and 300 as 
moderate condition, with moderate probability of occurrence and 
moderate abundance; and scores greater than 300 as low condition, with 
the lowest probability of occurrence or very low abundance and posing 
the highest levels of risk to the species (Service 2023, pp. 42-43; see 
table 4, below).
    Habitat quantity is another important metric to assess the current 
condition of the coal darter using HUC 12 watersheds as our units. The 
greater quantity of connected, suitable habitat available within a 
population, the greater the population resiliency. Resiliency was 
classified into one of three classes: High, Moderate, and Low. 
Thresholds for habitat quantity were established by enumerating extent 
of coal darter presence in the context of the historical range limits 
(see table 4, below).

   Table 4--Condition Categories for Demographic and Habitat Parameters Used To Assess Coal Darter Resiliency
                                              [Service 2023, p. 45]
----------------------------------------------------------------------------------------------------------------
                                                                   Condition category
              Parameter               --------------------------------------------------------------------------
                                               High (3)               Moderate (2)               Low (1)
----------------------------------------------------------------------------------------------------------------
Genetic health.......................  Genetic diversity        Genetic diversity        Genetic diversity
                                        considered               considered ``low''; N    considered ``very
                                        ``moderate'' or          exceeds the 500/1,000    low''; N does not
                                        ``high''; N exceeds      ``rule of thumb''        exceed the 500/1,000
                                        the 500/1,000 ``rule     threshold.               ``rule of thumb''
                                        of thumb'' threshold.                             threshold.
Percentage of historical range with    Greater than 66 percent  33-66 percent of         Less than 33 percent of
 current records.                       of historical range is   historical range is      historical range is
                                        currently occupied.      currently occupied.      currently occupied.
Human Disturbance Gradient Index       0-175..................  176-300................  Greater than 300.
 (HDGI).
Habitat quantity.....................  Greater than or equal    4-7 currently occupied   Fewer than 4 currently
                                        to 8 currently           HUC 12 units.            occupied HUC 12 units.
                                        occupied HUC 12 units.
----------------------------------------------------------------------------------------------------------------

    For each parameter, we assigned a score from 1 to 3 (1 = low, 2 = 
moderate, 3 = high) based on condition categories that we developed in 
coordination with species experts. For the overall resiliency of a 
population, scores were summed for all parameters. The minimum possible 
sum is 4 (a score of low for each of the four parameters), and the 
maximum possible sum is 12 (a score of high for each of the four 
parameters). We set thresholds for overall resiliency scores based on 
the minimum and maximum possible sums and the number of categories (3: 
high, moderate, low) (see table 5, below). The following discussion 
describes our reasoning for each parameter, the condition categories, 
and the methodology we used to derive an overall score for each factor.

[[Page 88349]]



                              Table 5--Thresholds for Overall Population Resiliency
                                              [Service 2023, p. 45]
----------------------------------------------------------------------------------------------------------------
                                                                         Overall population resiliency
                                                              --------------------------------------------------
                                                                     High           Moderate           Low
----------------------------------------------------------------------------------------------------------------
Parameter Score Sum..........................................           10-12              7-9              4-6
----------------------------------------------------------------------------------------------------------------

Resiliency
    Black Warrior--The overall resiliency for the Black Warrior 
population is moderate (see table 6, below). Genetic diversity, as 
expressed by observed and expected heterozygosity and percent 
polymorphic loci, is considered low for this population by experts. 
Additionally, the effective population size is higher than the 500 or 
1,000 ``rules of thumb'' threshold at 2,759 (range of 2,158-3,823) 
(Jones and Sandel 2019, pg. 5; Jones 2021, pg. 22). Due to the low 
genetic diversity but high effective population size (exceeding the 
500/1,000 threshold), a score of moderate is assigned for genetic 
health of the Black Warrior population. The Black Warrior population 
has experienced a 50 percent reduction, at minimum, in occupied range 
due to the installation of impoundments in the late 1800s and early 
1900s, resulting in a moderate score for the percentage of historical 
range with current records metric. The HDGI for the Black Warrior 
population is most heavily influenced by a combination of moderate 
amounts of development and urbanization in northern Jefferson County 
and more intensive livestock agriculture in the area. The averaged HDGI 
for currently occupied HUC 12 watersheds is 207, which results in a 
classification of moderate. With nine HUC 12 watersheds currently 
occupied, this population scores high for habitat quantity. However, 
despite the effects of these impacts, the Black Warrior population 
currently has an adequate effective population size and connectivity to 
support reproduction and recruitment.
    Cahaba--The Cahaba River is considered the stronghold for the 
species, reflected by consistent catch records from the 1960s to 
present day. Trends in population numbers can be difficult to discern 
due to differences in sampling methods and purpose over the years, but 
there continues to be evidence of reproduction and recruitment. 
However, there is evidence that population numbers of the coal darter 
may be declining in the Cahaba River, especially in the upper portion 
of the watershed around the Birmingham metropolitan area. A comparison 
by experts of historical fish community records spanning from 1964-1983 
to records obtained in 1994-1997 at 12 sites in the upper Cahaba River 
watershed in the Birmingham area indicated an overall decrease in fish 
species diversity, pointing to habitat degradation related to 
urbanization as the primary reason. Coal darters were found to have the 
greatest decline of all darter species, with 330 total specimens 
collected from historical samples (out of 46 samples) and only 6 
collected from the same sites in the 1995-1997 samples (out of 48 
samples). Along with coal darters, the study found disturbance-
sensitive species, in general, to have decreased in percent relative 
abundance (Service 2023, p. 47).
    The overall resiliency for the Cahaba population is moderate (see 
table 6, below). Genetic diversity of the Cahaba population is low, and 
the effective population size is higher than 500 or 1,000 ``rules of 
thumb'' threshold at 3,145 (range of 2,423-4,480) (Jones and Sandel 
2019, pg. 5; Jones 2021, pg. 22). Due to the low genetic diversity but 
high effective population size (exceeding the 500/1,000 threshold), the 
Cahaba population scores moderate for genetic health (see table 6, 
below). The population genetic results indicate that the Cahaba 
population currently has a lower expected heterozygosity and percent 
polymorphic loci when compared to the Black Warrior population, yet a 
higher effective population size than the Black Warrior population 
(Service 2023, p. 46). One explanation for this could be a decrease in 
population size because of degraded water quality in the Cahaba River 
beginning in the early 1900s up to the enactment of the CWA (1972). A 
significant decrease in the number of individuals in this population 
would have resulted in a loss of genetic diversity. Because of their 
short generation time, coal darter numbers may have been able to 
rebound faster than it would take to increase genetic diversity since 
the latter would be dependent on the accumulation of novel mutations 
which would be expected to occur over thousands of years.
    The Cahaba population has experienced the least reduction in range 
of the three populations. No major impoundments were constructed within 
the mainstem of the Cahaba River. However, a single low head dam 
located at Highway 280 currently prevents movement of coal darters 
upstream. While the species still occupies sites approximately 20 miles 
upstream of this dam, those individuals are isolated from downstream 
individuals and gene flow is likely unidirectional, creating a greater 
risk of further loss in genetic diversity in this portion of the river 
(Zarri et al. 2022, entire). To date, no range reduction of the species 
due to this dam has been observed. The Cahaba population scores high 
for the percentage of historical range with current records metric (see 
table 6, below).
    The Cahaba River HDGI score is largely influenced by intense 
urbanization associated with the City of Birmingham and its suburbs. 
The averaged HDGI for currently occupied HUC 12 watersheds is 356 
(Service 2023, p. 46), which results in a score of low for the Cahaba 
population (see table 6, below). Eight HUC 12 watersheds are currently 
occupied, which results in a score of high for habitat quantity (see 
table 6, below).
    Coosa--The overall resiliency for the Coosa population is low (see 
table 6, below). Genetic diversity is considered very low for this 
population. Since Weogufka Creek discovered individuals in 2021 
following the completion of the genetic analysis, only the Hatchet 
Creek population was used in the Coosa River system genetics results, 
The effective population size is above the ``rule of thumb'' threshold 
of 50 or 100 that is necessary to prevent deleterious effects of 
inbreeding depression and genetic drift. However, the effective 
population size is still considered low at 268 (range of 252-290) 
(Jones and Sandel 2019, pg. 5; Jones 2021, pg. 22) and is an order of 
magnitude lower than the other two populations. Furthermore, the 
effective population for Hatchet Creek falls in between the upper and 
lower bounds of the 50/500 and 100/1,000 rule thresholds, indicating 
that the population is at high risk of continual loss of genetic 
diversity. This low effective population size may also reflect the 
ongoing deleterious genetic effects of a population bottleneck or the

[[Page 88350]]

ongoing habitat limitations that prevent population sizes reaching 
those found in the other two populations or both (Franklin 1980, pp. 
135-149; Frankham et al. 2014, pp. 56-63; Franklin et al. 2014, pp. 
284-285). Based on the lower effective population size in Hatchet Creek 
coupled with the very low genetic diversity, the Coosa population 
results in a score of low for genetic health (see table 6, below).
    The Coosa population has experienced the greatest range reduction 
of the three coal darter populations. With a 90 percent reduction in 
range compared to pre-impoundment historical condition, this population 
is assessed a score of low for the percentage of historical range with 
current records metric (see table 6, below).
    The HDGI for the Lower Weogufka Creek HUC 12 had a value of 51.5, 
and the HDGI for the Lower Hatchet Creek HUC 12 had a value of 40.7 
(Service 2023, p. 49). The averaged HDGI score for currently occupied 
HUC 12 watersheds is 46, which results in a score of high for the HDGI 
metric for this population (see table 6, below).
    Regarding the habitat quantity metric for the Coosa population, 
only two HUC 12 watersheds are currently occupied: Lower Hatchet Creek 
and Lower Weogufka Creek. Within these two HUC 12 boundaries, the coal 
darter is only known from one site in Weogufka Creek and 14.5 rkm (9 
rmi) of Hatchet Creek. Because of the low quantity of occupied habitat, 
this population scores low for the habitat quantity factor.

                 Table 6--Current Condition Resiliency Results by Population for the Coal Darter
                                              [Service 2023, p. 50]
----------------------------------------------------------------------------------------------------------------
                                                                     Population
              Factor              ------------------------------------------------------------------------------
                                       Black Warrior            Cahaba                       Coosa
----------------------------------------------------------------------------------------------------------------
Genetic health...................  Moderate (2)........  Moderate (2).......  Low (1).
Percentage of historical range     50 percent: Moderate  90 percent: High     10 percent: Low (1).
 with current records.              (2).                  (3).
Human Disturbance Gradient Index   207: Moderate (2)...  356: Low (1).......  46: High (3).
 (HDGI).
Habitat quantity.................  9: High (3).........  8: High (3)........  2: Low (1).
Overall resiliency...............  Moderate (9)........  Moderate (9).......  Low (6).
----------------------------------------------------------------------------------------------------------------

Representation
    Representation is the ability of a species to adapt to both near-
term and long-term changes in its physical and biological environment. 
The best available scientific information suggests using population 
genetic analyses to characterize the coal darter's current adaptive 
capacity. Due to the current isolation of coal darter populations, it 
is unlikely that gene flow exists among rivers (to increase genetic 
diversity), or that darter populations are able to shift to track 
suitable habitat conditions. Isolated coal darter populations must 
adapt to changing conditions in place, requiring sufficient genetic 
variation in order to respond to shifting selection pressures and any 
unexpected selection events, such as introduction of a novel disease or 
invasive species (Service 2023, p. 52).
    The Cahaba River and Black Warrior populations meet the effective 
population size threshold ``rule of thumb'' of 500 or 1,000 to maintain 
evolutionary potential and adaptive capacity over time. By contrast, 
the Coosa population does not meet these effective population size 
thresholds for retaining adaptive potential. Coupled with its low 
genetic diversity, this population is at high risk of ongoing losses of 
standing genetic variation, lowering its capacity to respond to 
changing selection pressures.
    We estimate that the coal darter has low adaptive capacity based on 
the poor genetic condition of the Coosa population; the low genetic 
diversity, yet sufficient effective population sizes, of the Black 
Warrior and Cahaba populations; and the lack of connectivity between 
populations. Overall representation for the coal darter is currently 
low.
Redundancy
    Redundancy refers to the ability of a species to withstand 
catastrophic events and is measured by the amount and distribution of 
resilient populations across the species' range. Catastrophic events 
that could severely affect or extirpate entire coal darter populations 
include gas pipeline bursts and associated spills, changes in upstream 
land use that alter stream characteristics and water quality, and 
potential effects of climate change such as drought and increases in 
occurrence of flash-flooding events.
    Redundancy is characterized by having multiple, resilient and 
representative populations of the coal darter distributed throughout 
the species' range. While there remain three populations distributed 
throughout the range and at a scale for which it would be unlikely for 
a single event to catastrophically affect all, one population (Coosa) 
has low resiliency to stochastic events and a higher risk of 
extirpation. The remaining two populations (Black Warrior and Cahaba) 
were found to be moderately resilient to stochastic events. Each 
population's reduced resiliency prevents them from fully contributing 
to a high level of redundancy; therefore, the coal darter currently 
exhibits a moderate level of redundancy.

Future Condition

    A thorough review of the coal darter's future condition is 
presented in chapter 6 of the SSA report (version 1.1, Service 2023, 
pp. 54-58).
    In our SSA report (version 1.1, Service 2023, entire), we define 
viability as the ability of the coal darter to sustain natural 
populations in river and stream systems over time. In our assessments 
of factors influencing viability and current condition, we found that 
disturbance on the landscape negatively affects the coal darter's 
ability to sustain natural populations and these disturbances can be 
attributed and measured by quantifying land use and cover types. To 
help address uncertainty associated with the degree and extent of 
potential future stressors and their impacts on the species' needs, the 
concepts of resiliency, redundancy, and representation were assessed 
using two scenarios and time stepped them at years 2040 and 2050. We 
devised these scenarios by identifying information on primary threat 
factors arising from increasing human populations and resulting 
alterations to the habitat. The four scenarios use the EPA's Integrated 
Climate and Land Use (ICLUS; version 2.1.1, EPA 2017) model, which uses 
human demography as a primary means to project local land-use changes 
in the future with consideration of climate change. It is consistent 
with updated global socioeconomic scenarios (shared

[[Page 88351]]

socioeconomic pathways (SSPs)) and global climate change model targets 
(representative concentration pathways (RCPs)). Using the ICLUS models, 
we projected the future resiliency of coal darter populations using two 
future scenarios that consider a range of impacts from future 
urbanization and land-use change along with climate change effects. 
Data from the ICLUS model was used to predict future HDGI scores, which 
can be compared with the HDGI scores of each population from our 
current condition analysis. While other stressors were identified as 
factors influencing viability, such as impoundments and genetic health, 
we were unable to model these factors into the future. However, these 
stressors are expected to continue to limit the species' viability into 
the future. Dams and impoundments are expected to constrain population 
extent, and genetic health is not expected to improve due to the long 
period of time required for mutations to occur that would improve 
genetic diversity (Service 2023, pp. 23-31).
    We used the best available data and models to project changes in 
human disturbance under a high impact scenario and a moderate impact 
scenario at year 2040 and 2050 (20 and 30 years). This timeframe was 
reasonably certain to predict patterns of urbanization and agriculture, 
and how these land uses forecast patterns in the species' range 
relevant to the coal darter and its habitat given the species' short 
lifespan. In addition, catastrophic events (for example, invasive 
species, disease, and chemical spills) could have an immediate impact 
on the species, especially on the Coosa population due to its limited 
abundance and distribution.
    Results of HDGI under the two future scenarios did not vary greatly 
between the two scenarios within each population (Black Warrior: 610 
and 635; Cahaba: 636 and 661; Coosa: 77 and 141) (Service 2023, pp. 56-
59). As stated above under Current Condition, HDGI scores below 175 are 
classified as high condition or most suitable for the coal darter, with 
high probability of occurrence and high abundance; scores of between 
176 and 300 correspond to moderate condition, with moderate probability 
of occurrence and moderate abundance; and scores greater than 300 are 
classified as low condition, with the lowest probability of occurrence 
or very low abundance and posing the highest levels of risk to the 
species.
    When compared to the current condition's HDGI, the Black Warrior 
and Cahaba populations' future HDGI scores nearly tripled and doubled, 
respectively. Therefore, aquatic habitats currently occupied by the 
coal darter will experience substantial levels of disturbance due to 
human urbanization activities, and the species' likelihood of presence 
and abundance will continue to decline. Furthermore, the habitat 
quantity will also decrease. Due to the significant projected increase 
in human disturbance within the Black Warrior and Cahaba populations, 
resiliency of each of these populations is projected to decrease from 
moderate to low under all future scenarios (Service 2023, p. 56).
    While the future HDGI did not indicate poor habitat condition in 
the Coosa population, no habitat improvements are projected. The Coosa 
population of the coal darter is confined to small reaches of Hatchet 
and Weogufka creeks. These two tributaries of the Coosa River likely 
represent peripheral habitat that was sustained by now extirpated 
source populations in the Coosa River. As flow appears to be a 
predictor of species presence, population expansion in these streams is 
constrained by the lack of suitable flows and habitat in the upstream 
reaches. Further, given the natural state of these streams, it is 
unlikely density could increase. That is, the populations are likely at 
carrying capacity within these refugia. The Coosa population's poor 
genetic health is projected to decline without the influx of any new 
genetic material. Therefore, projected resiliency of the Coosa 
population remains low (Service 2023, p. 56).
    The overall projected decline in resiliency decreases the Black 
Warrior and Cahaba populations' contribution to future redundancy. 
Therefore, catastrophic events that occur across the regional or State 
scale could cause extirpation in both populations. Furthermore, the 
current low resiliency in the Coosa population leaves it susceptible to 
extirpation, and with heavy land-use changes projected to occur on the 
landscape surrounding this population, this population is likely to be 
extirpated by the 2040 and 2050 time steps. For these reasons, the 
overall redundancy under all future scenarios is low.
    We do not anticipate any improvement to the connectivity or 
adaptive capacity of the species. While our current condition 
assessment finds sufficient effective population size in the Black 
Warrior and Cahaba populations, the amount of habitat disturbance 
projected to occur, and probable range contraction, will reduce the 
effective population size and genetic diversity of these two 
populations. The overall representation for the coal darter under all 
future scenarios is assessed as low.

Determination of Coal 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 in danger of extinction throughout all or a significant portion 
of its range, and a ``threatened species'' as a species likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether a species meets the definition of an endangered 
species or a threatened species because of any of the following 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence.

Status Throughout All of Its Range

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the coal darter. We considered whether the coal darter is presently 
in danger of extinction. Our review of the best available information 
indicates there are three populations across the known historical range 
in the Locust Fork of the Black Warrior River system, the Cahaba River 
system, and the Hatchet and Weogufka Creeks of the Coosa River system 
in Alabama. Genetic analysis indicates that the three populations were 
previously connected but are currently isolated and uniquely 
identifiable populations. Based on the coal darter's individual and 
population needs, an approach including two key habitat (Human 
Disturbance Gradient Index (HDGI) and habitat quantity) factors and two 
demographic (genetic health and persistence through time) factors was 
used to assess population resiliency with an assigned score of high, 
moderate, or low.
    The current resiliency for both the Black Warrior and Cahaba 
populations is moderate. Impacts from habitat destruction and 
modification; the reduction of range as a result of impoundments (Black 
Warrior); and water quality degradation resulting from urbanization, 
mining, and agriculture (Factors A and E) appear to be affecting the 
coal darter at the population level

[[Page 88352]]

for these two resiliency units. Both also have low genetic diversity. 
The Black Warrior population has experienced at least a 50 percent 
reduction in occupied range due to the installation of impoundments in 
the late 1800s and early 1900s. However, despite the effects of these 
impacts, the Black Warrior and Cahaba populations currently have 
adequate effective population sizes and connectivity to support 
reproduction and recruitment. The Cahaba population has experienced the 
smallest range reduction (14 percent) of the three populations and has 
had no major impoundments constructed within the mainstem of the Cahaba 
River. It is considered the stronghold for the species.
    The Coosa population has low resiliency due to habitat destruction 
and degradation resulting from dams and impoundments (Factors A and E). 
Only two HUC 12 watersheds are currently occupied in the Coosa 
population: Lower Hatchet Creek and Lower Weogufka Creek. Within these 
two HUC 12 boundaries, the coal darter is only known from one site in 
lower Weogufka Creek and 9 rmi (14.5 rkm) of lower Hatchet Creek. The 
genetic diversity is currently very low for this population (an order 
of magnitude lower than the other two populations), and its inadequate 
effective population size is vulnerable to the deleterious effects of 
inbreeding depression and genetic drift. This low effective population 
size may also reflect the ongoing harmful genetic effects of a 
population bottleneck or the ongoing habitat limitations that prevent 
population sizes reaching those found in the other two populations or 
both.
    The species is currently extant in all three representation units, 
with two resiliency units (Black Warrior and Cahaba) having moderate 
resiliency. Both units with moderate resiliency contain effective 
populations sizes necessary for retaining adaptive potential. In 
contrast, the one unit (Coosa) with low resiliency does not meet the 
effective population size threshold for retaining adaptive potential. 
Coupled with low genetic diversity, the Coosa unit is currently at high 
risk of ongoing losses of standing genetic variation, lowering its 
capacity to respond to changing selection pressures.
    The three populations are distributed across northern Alabama, and 
two of the three units across the range currently have moderate 
resiliency, which bolsters the species' ability to withstand 
catastrophic events. However, a catastrophic event (such as a chemical 
spill, change in upstream land use that alters stream characteristics 
and water quality, new impoundment, drought, or flash flood) could 
severely affect or extirpate coal darter populations such that the 
species is affected as a whole. This is exacerbated by one population 
(Coosa) having low resiliency to stochastic events and being at a 
higher risk of extirpation, while the remaining two populations (Black 
Warrior and Cahaba) have moderate resiliency to respond to stochastic 
events. Connectivity does not exist between any of the extant units. 
However, the species is not presently facing threats that place it at 
risk of extinction throughout all its range. Further, while multiple 
populations exist, each population's low or moderate resiliency 
contributes to a moderate level of redundancy for the species. 
Therefore, we find that the species does not meet the definition of an 
endangered species.
    We forecasted the viability of the coal darter under four plausible 
scenarios into the future (summarized above under Future Condition). We 
assessed relevant risk factors that may be acting on the coal darter in 
the future and whether we could make reliable predictions about these 
factors and how they may impact the viability of the species. Since the 
main threats arise from increasing human populations and resultant 
alterations to the habitat, we used human demography as a means to 
project land-use changes in the future with consideration of climate 
change. We projected changes in human disturbance under two scenarios 
at year 2040 and 2050 (i.e., 20 and 30 years). In considering the 
foreseeable future as it relates to the status of the coal darter, we 
considered the relevant risk factors (threats/stressors) acting on the 
species and whether we could draw reliable predictions about the 
species' response to these factors. Our analysis in the SSA report of 
future scenarios over an approximately 30-year timeframe encompasses 
the best available information for future projections of land-use 
change. We determined that this approximately 30-year timeframe enables 
us to consider the threats/stressors acting on the species and draw 
reliable predictions about the species' response to these factors. This 
30-year timeframe allows multiple generations of the short-lived coal 
darter to respond to potential land-use changes.
    Taking into account the primary factors influencing the species in 
the future (habitat destruction and degradation caused by land uses, 
and loss of connectivity between populations) and the potential impacts 
to the species' needs, we project a decline in resiliency for the coal 
darter throughout its range. The current low resiliency in the Coosa 
population leaves it vulnerable to extirpation, especially considering 
the major land-use changes expected to occur to this landscape, and 
this population is projected to remain in low condition. Furthermore, 
the Black Warrior and Cahaba populations are projected to decline in 
resiliency, as will their projected contribution to redundancy over the 
next 30 years. Therefore, potential catastrophic events occurring 
across the Southeast or in the State of Alabama could result in 
extirpation of any of the populations. Given the scenarios assessed, it 
is projected that aquatic habitats currently occupied by the coal 
darter will experience substantial levels of disturbance due to human 
activities, reducing the amount of habitat available to the species and 
corresponding to declines in the species' likelihood of presence and 
abundance. For these reasons, the overall projected redundancy for the 
coal darter under all future scenarios is low.
    Future projections also indicate that the coal darter will continue 
to have low adaptive capacity (low representation) based on (1) the 
poor genetic condition of the Coosa population, if it remains extant in 
the future; (2) the low genetic diversity of the Black Warrior and 
Cahaba populations; and (3) the lack of connectivity between 
populations. Further, while the current condition assessment found 
sufficient effective population sizes in the Black Warrior and the 
Cahaba populations, the amount of habitat disturbance and range 
contractions that are projected to occur would likely reduce the 
effective population sizes and genetic diversity of these two 
populations. For these reasons, the overall projected representation 
for the coal darter under all future scenarios is low. From our future 
scenario assessment, we find that the coal darter will be at risk of 
extinction, and therefore is likely to become endangered, within the 
foreseeable future (i.e., within the next 30 years) throughout all of 
its range.
    Based on projected future threats, the coal darter will not have 
sufficient resiliency, redundancy, and representation to support 
species' viability. Overall, the future threats are projected to 
increase in magnitude and severity such that the coal darter is at risk 
of extinction throughout all of its range. Thus, after assessing the 
best available information, we conclude that the coal darter is likely 
to become in danger of extinction within the foreseeable future 
throughout all of its range.

[[Page 88353]]

Status Throughout a Significant Portion of Its Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
within the foreseeable future throughout all or a significant portion 
of its range. The court in Center for Biological Diversity v. Everson, 
435 F. Supp. 3d 69 (D.D.C. 2020) (Everson), vacated the provision of 
the Final Policy on Interpretation of the Phrase ``Significant Portion 
of Its Range'' in the Endangered Species Act's Definitions of 
``Endangered Species'' and ``Threatened Species'' (hereafter ``Final 
Policy''; 79 FR 37578, July 1, 2014) that provided if the Service 
determines that a species is threatened throughout all of its range, 
the Service will not analyze whether the species is endangered in a 
significant portion of its range.
    Therefore, we proceed to evaluating whether the species is 
endangered in a significant portion of its range--that is, whether 
there is any portion of the species' range for which both (1) the 
portion is significant; and (2) the species is in danger of extinction 
in that portion. Depending on the case, it might be more efficient for 
us to address the ``significance'' question or the ``status'' question 
first. We can choose to address either question first. Regardless of 
which question we address first, if we reach a negative answer with 
respect to the first question that we address, we do not need to 
evaluate the other question for that portion of the species' range.
    Following the court's holding in Everson, we now consider whether 
there are any significant portions of the species' range where the 
species is in danger of extinction now (i.e., endangered). In 
undertaking this analysis for coal 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 portions of the range where the species may 
be endangered.
    We evaluated the range of the coal darter to determine if the 
species is in danger of extinction now in any portion of its range. The 
range of a species can theoretically be divided into portions in an 
infinite number of ways. We focused our analysis on portions of the 
species' range that may meet the definition of an endangered species. 
For the coal darter, we considered whether the threats or their effects 
on the species are greater in any biologically meaningful portion of 
the species' range than in other portions such that the species is in 
danger of extinction now in that portion.
    The statutory difference between an endangered species and a 
threatened species is the timeframe in which the species becomes in 
danger of extinction; an endangered species is in danger of extinction 
now while a threatened species is not in danger of extinction now but 
is likely to become so within the foreseeable future. Thus, we 
considered the time horizon for the threats that are driving the coal 
darter to warrant listing as a threatened species throughout all of its 
range. We then considered whether these threats or their effects are 
occurring in any portion of the species' range such that the species is 
in danger of extinction now in that portion of its range. We examined 
the following threats: habitat degradation or loss stemming from 
hydrologic alteration by impoundments, including dams and other 
barriers; habitat degradation or loss stemming from urban development 
or change in land cover, including increased density of residential and 
commercial infrastructure; resource extraction, including mining and 
timber operations; agriculture, including poultry farming; and 
diminished water quality from point and nonpoint source chemical 
contamination and siltation, including cumulative effects.
    We identified that the Coosa portion of the species' range is 
experiencing a concentration of the following threat at a biologically 
meaningful scale: habitat destruction and degradation from land uses 
and impoundments resulting in poor water quality (Factor A). Currently, 
the Coosa population unit has low resiliency, with only two HUC 12 
watersheds currently occupied: Lower Hatchet Creek and Lower Weogufka 
Creek. This population unit has experienced the greatest range 
reduction (a loss of 90 percent of its historical range) of the three 
coal darter populations, and its low effective population size is an 
order of magnitude lower than the other two populations. Overall, the 
Coosa population lacks any adaptive potential, and it is likely that a 
single catastrophic event would result in the extirpation of the 
species from this portion. Based on this information, we conclude that 
the impacts are having a biologically meaningful effect on the Coosa 
population. Therefore, the best scientific and commercial information 
indicates that the Coosa population may have a different status than 
the other two populations in the species' range.
    We then proceeded to consider whether this portion of the range 
(i.e., the Coosa population) is significant. The Service's most recent 
definition of ``significant'' within agency policy guidance has been 
invalidated by court order (see Desert Survivors v. U.S. Department of 
the Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 2018)). In 
undertaking this analysis for the coal darter, we considered whether 
the Coosa population portion of the species' range may be significant. 
Therefore, for the purposes of this analysis, when considering whether 
this portion is significant, we considered whether the portion may (1) 
occur in a unique habitat or ecoregion for the species; (2) contain 
high-quality or high-value habitat relative to the remaining portions 
of the range, for the species' continued viability in light of the 
existing threats; (3) contain habitat that is essential to a specific 
life-history function for the species and that is not found in the 
other portions (for example, the principal breeding ground for the 
species); or (4) contain a large geographic portion of the suitable 
habitat relative to the remaining portions of the range for the 
species.
    Currently, the Coosa population represents a small portion (less 
than 5 percent based on current occurrences and occupied stream 
reaches) of the coal darter's range. In addition, this portion does not 
have any areas of habitat that are unique or that contain high-quality 
or high-value habitat relative to the remaining portions of the range. 
The Coosa population also does not contain habitat that is essential to 
a specific life-history function. Overall, we found no information that 
would indicate that the Coosa population constitutes a portion of the 
range that may be significant in terms of its geographic portion of 
suitable habitat, or that it is significant in terms of high-quality 
habitat or otherwise important for the species' life history.
    The best scientific and commercial data available indicate that no 
portion of the species' range provides a basis for determining that the 
species is in danger of extinction in a significant portion of its 
range, and we determine that the species is likely to become in danger 
of extinction within the foreseeable future throughout all of its 
range. This does not conflict with the courts' holdings in Desert 
Survivors v. U.S. Department of the Interior, 321 F. Supp. 3d 1011, 
1070-74 (N.D. Cal. 2018) and Center for Biological Diversity v. Jewell, 
248 F. Supp. 3d 946, 959 (D. Ariz. 2017) because, in reaching this 
conclusion, we did not apply the aspects of the Final Policy, including 
the definition of ``significant,'' that those court decisions held to 
be invalid.

Determination of Status

    Our review of the best available scientific and commercial 
information

[[Page 88354]]

indicates that the coal darter meets the Act's definition of a 
threatened species. Therefore, we propose to list the coal darter as a 
threatened species in accordance with sections 3(20) and 4(a)(1) of the 
Act.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition as a listed 
species, planning and implementation of recovery actions, requirements 
for Federal protection, and prohibitions against certain practices. 
Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies, 
including the Service, and the prohibitions against certain activities 
are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Section 4(f) of the Act calls for the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The goal of this process is to restore listed 
species to a point where they are secure, self-sustaining, and 
functioning components of their ecosystems.
    The recovery planning process begins with development of a recovery 
outline made available to the public soon after a final listing 
determination. The recovery outline guides the immediate implementation 
of urgent recovery actions while a recovery plan is being developed. 
Recovery teams (composed of species experts, Federal and State 
agencies, nongovernmental organizations, and stakeholders) may be 
established to develop and implement recovery plans. The recovery 
planning process involves the identification of actions that are 
necessary to halt and reverse the species' decline by addressing the 
threats to its survival and recovery. The recovery plan identifies 
recovery criteria for review of when a species may be ready for 
reclassification from endangered to threatened (``downlisting'') or 
removal from protected status (``delisting''), and methods for 
monitoring recovery progress. Recovery plans also establish a framework 
for agencies to coordinate their recovery efforts and provide estimates 
of the cost of implementing recovery tasks. Revisions of the plan may 
be done to address continuing or new threats to the species, as new 
substantive information becomes available. The recovery outline, draft 
recovery plan, final recovery plan, and any revisions will be available 
on our website as they are completed (https://www.fws.gov/program/endangered-species), or from our Alabama Ecological Services Field 
Office (see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their 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 Alabama would be 
eligible for Federal funds to implement management actions that promote 
the protection or recovery of the coal darter. Information on our grant 
programs that are available to aid species recovery can be found at: 
https://www.fws.gov/service/financial-assistance.
    Although the coal darter 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 of the Act is titled, ``Interagency Cooperation,'' and it 
mandates all Federal action agencies to use their existing authorities 
to further the conservation purposes of the Act and to ensure that 
their actions are not likely to jeopardize the continued existence of 
listed species or adversely modify critical habitat. Regulations 
implementing section 7 are codified at 50 CFR part 402.
    Section 7(a)(2) states that each Federal action agency shall, in 
consultation with the Secretary, ensure that any action they authorize, 
fund, or carry out is not likely to jeopardize the continued existence 
of a listed species or result in the destruction or adverse 
modification of designated critical habitat. Each Federal agency shall 
review its action at the earliest possible time to determine whether it 
may affect listed species or critical habitat. If a determination is 
made that the action may affect listed species or critical habitat, 
formal consultation is required (see 50 CFR 402.14(a)), unless the 
Service concurs in writing that the action is not likely to adversely 
affect listed species or critical habitat. At the end of a formal 
consultation, the Service issues a biological opinion, containing its 
determination of whether the Federal action is likely to result in 
jeopardy or adverse modification.
    In contrast, section 7(a)(4) of the Act requires Federal agencies 
to confer with the Service on any action which is likely to jeopardize 
the continued existence of any species proposed to be listed under the 
Act or result in the destruction or adverse modification of critical 
habitat proposed to be designated for such species. Although the 
conference procedures are required only when an action is likely to 
result in jeopardy or adverse modification, action agencies may 
voluntarily confer with the Service on actions that may affect species 
proposed for listing or critical habitat proposed to be designated. In 
the event that the subject species is listed or the relevant critical 
habitat is designated, a conference opinion may be adopted as a 
biological opinion and serve as compliance with section 7(a)(2) of the 
Act.
    Examples of discretionary actions for the coal darter that may be 
subject to conference and consultation procedures under section 7 of 
the Act are land management or other landscape-altering activities on 
Federal lands administered by the U.S. Department of Agriculture's U.S. 
Forest Service or Natural Resources Conservation Service, the U.S. 
Geological Survey, and the U.S. Army Corps of Engineers, as well as 
actions on State, Tribal, local, or private lands that require a 
Federal permit (such as a permit from the U.S. Army Corps of Engineers 
under section 404 of the CWA or a permit from the Service under section 
10 of the Act) or that involve some other Federal action (such as 
funding from the Federal Highway Administration, Federal Aviation

[[Page 88355]]

Administration, or Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat--and actions 
on State, Tribal, local, or private lands that are not funded, 
authorized, or carried out by a Federal agency--do not require section 
7 consultation. Federal agencies should coordinate with the local 
Service Field Office (see FOR FURTHER INFORMATION CONTACT) with any 
specific questions on section 7 consultation and conference 
requirements.
    It is the policy of the Service, as published in the Federal 
Register on July 1, 1994 (59 FR 34272), to identify to the extent known 
at the time a species is listed, specific activities that will not be 
considered likely to result in violation of section 9 of the Act. To 
the extent possible, activities that will be considered likely to 
result in violation will also be identified in as specific a manner as 
possible. The intent of this policy is to increase public awareness of 
the effect of a proposed listing on proposed and ongoing activities 
within the range of the species proposed for listing. Although most of 
the prohibitions in section 9 of the Act apply to endangered species, 
sections 9(a)(1)(G) and 9(a)(2)(E) of the Act prohibit the violation of 
any regulation, including a rule issued under section 4(d) of the Act 
pertaining to any threatened species of fish or wildlife, or threatened 
species of plant, respectively. Section 4(d) of the Act directs the 
Secretary to promulgate protective regulations that are necessary and 
advisable for the conservation of threatened species. As a result, we 
interpret our policy to mean that, when we list a species as a 
threatened species, to the extent possible, we identify activities that 
will or will not be considered likely to result in violation of the 
protective regulations under section 4(d) for that species.
    At this time, we are unable to identify specific activities that 
will or will not be considered likely to result in violation of section 
9 of the Act beyond what is already clear from the descriptions of 
prohibitions and exceptions we would establish by protective regulation 
under section 4(d) of the Act (see Provisions of the Proposed 4(d) 
Rule, below).
    Questions regarding whether specific activities would constitute 
violation of section 9 of the Act should be directed to the Alabama 
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT).

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

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the Secretary shall issue such regulations as she deems 
necessary and advisable to provide for the conservation of species 
listed as threatened species. The U.S. Supreme Court has noted that 
statutory language similar to the language in section 4(d) of the Act 
authorizing the Secretary to take action that she ``deems necessary and 
advisable'' affords a large degree of deference to the agency (see 
Webster v. Doe, 486 U.S. 592, 600 (1988)). Conservation is defined in 
the Act to mean the use of all methods and procedures which are 
necessary to bring any endangered species or threatened species to the 
point at which the measures provided pursuant to the Act are no longer 
necessary. Additionally, the second sentence of section 4(d) of the Act 
states that the Secretary may by regulation prohibit with respect to 
any threatened species any act prohibited under section 9(a)(1), in the 
case of fish or wildlife, or section 9(a)(2), in the case of plants. 
Thus, the combination of the two sentences of section 4(d) provides the 
Secretary with wide latitude of discretion to select and promulgate 
appropriate regulations tailored to the specific conservation needs of 
the threatened species. The second sentence grants particularly broad 
discretion to the Service when adopting one or more of the prohibitions 
under section 9.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld, as a valid 
exercise of agency authority, rules developed under section 4(d) that 
included limited prohibitions against takings (see Alsea Valley 
Alliance v. Lautenbacher, 2007 WL 2344927 (D. Or. 2007); Washington 
Environmental Council v. National Marine Fisheries Service, 2002 WL 
511479 (W.D. Wash. 2002)). Courts have also upheld 4(d) rules that do 
not address all of the threats a species faces (see State of Louisiana 
v. Verity, 853 F.2d 322 (5th Cir. 1988)). As noted in the legislative 
history when the Act was initially enacted, ``once an animal is on the 
threatened list, the Secretary has an almost infinite number of options 
available to [her] with regard to the permitted activities for those 
species. [She] may, for example, permit taking, but not importation of 
such species, or [she] may choose to forbid both taking and importation 
but allow the transportation of such species'' (H.R. Rep. No. 412, 93rd 
Cong., 1st Sess. 1973).
    The provisions of this proposed 4(d) rule would promote 
conservation of the coal darter by encouraging management of the 
landscape in ways that meet both watershed and riparian management 
purposes and facilitate the conservation of the species. The provisions 
of this proposed 4(d) rule are one of many tools that we would use to 
promote the conservation of the coal darter. This proposed 4(d) rule 
would apply only if and when we make final the listing of the coal 
darter as a threatened species.
    As mentioned previously in Available Conservation Measures, section 
7(a)(2) of the Act requires Federal agencies, including the Service, to 
ensure that any action they authorize, fund, or carry out is not likely 
to jeopardize the continued existence of any endangered species or 
threatened species or result in the destruction or adverse modification 
of designated critical habitat of such species. In addition, even 
before the listing of any species or the designation of its critical 
habitat is finalized, section 7(a)(4) of the Act requires Federal 
agencies to confer with the Service on any agency action which is 
likely to jeopardize the continued existence of any species proposed to 
be listed under the Act or result in the destruction or adverse 
modification of critical habitat proposed to be designated for such 
species.
    These requirements are the same for a threatened species with a 
species-specific 4(d) rule. For example, as with an endangered species, 
if a Federal agency determines that an action is ``not likely to 
adversely affect'' a threatened species, it will require the Service's 
written concurrence (see 50 CFR 402.13(c)). Similarly, if a Federal 
agency determinates that an action is ``likely to adversely affect'' a 
threatened species, the action will require formal consultation with 
the Service and the formulation of a biological opinion (see 50 CFR 
402.14(a)).

Provisions of the Proposed 4(d) Rule

    Exercising the Secretary's authority under section 4(d) of the Act, 
we have developed a proposed rule that is designed to address the coal 
darter's conservation needs. As discussed previously under Summary of 
Biological Status and Threats, we have concluded that the darter is 
likely to become in danger of extinction within the foreseeable future 
primarily due to habitat loss or degradation from the following 
activities or conditions: hydrologic alteration by impoundments, 
including dams and other barriers;

[[Page 88356]]

agriculture (poultry farming); urban development or change in land 
cover, including increased density of residential and commercial 
infrastructure; resource extraction, including mining and silviculture 
operations that do not follow State-approved BMPs; diminished water 
quality from point and nonpoint source chemical contamination and 
sedimentation; and climate change. Section 4(d) requires the Secretary 
to issue such regulations as she deems necessary and advisable to 
provide for the conservation of each threatened species and authorizes 
the Secretary to include among those protective regulations any of the 
prohibitions that section 9(a)(1) of the Act prescribes for endangered 
species. We find that, if finalized, the protections, prohibitions, and 
exceptions in this proposed 4(d) rule as a whole satisfy the 
requirement in section 4(d) of the Act to issue regulations deemed 
necessary and advisable to provide for the conservation of the coal 
darter.
    The protective regulations we are proposing for the coal darter 
incorporate prohibitions from section 9(a)(1) of the Act to address the 
threats to the species. Section 9(a)(1) prohibits the following 
activities for endangered wildlife: importing or exporting; take; 
possession and other acts with unlawfully taken specimens; delivering, 
receiving, carrying, transporting, or shipping in interstate or foreign 
commerce in the course of commercial activity; or selling or offering 
for sale in interstate or foreign commerce. This protective regulation 
includes all of these prohibitions because the coal darter is at risk 
of extinction within the foreseeable future and putting these 
prohibitions in place would help to preserve the species' remaining 
populations and decrease synergistic, negative effects from other 
ongoing or future threats.
    In particular, this proposed 4(d) rule would provide for the 
conservation of the coal darter by prohibiting the following 
activities, unless they fall within specific exceptions or are 
otherwise authorized or permitted: import or export; take; possession 
and other acts with unlawfully taken specimens; delivery, receipt, 
carriage, transport, or shipment in interstate or foreign commerce in 
the course of commercial activity; and sale or offer for sale in 
interstate or foreign commerce. We also include several exceptions to 
these prohibitions, which, along with the prohibitions, are set forth 
below.
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulations at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Regulating 
take would help preserve the species' remaining populations and slow 
their rate of decline. Therefore, we propose to prohibit take of the 
coal darter, except for take resulting from those actions and 
activities specifically excepted by the 4(d) rule. Exceptions to the 
prohibition on take would include all of the general exceptions to the 
prohibition on take of endangered wildlife, as set forth in 50 CFR 
17.21, and additional exceptions, as described below.
    The proposed 4(d) rule would also provide for the conservation of 
the species by allowing exceptions that incentivize conservation 
actions or that, while they may have some minimal level of take of the 
coal darter, are not expected to rise to the level that would have a 
negative impact (i.e., would have only de minimis impacts) on the 
species' conservation. The proposed exceptions to the prohibitions 
include: take incidental to any otherwise lawful activity caused by 
channel restoration; streambank restoration; habitat improvement 
activities; and silviculture and forestry activities that follow best 
management practices (described below). These are expected to have 
negligible impacts to the coal darter and its habitat.
    Channel Restoration--Channel restoration is used as a technique to 
restore degraded, physically unstable streams back to natural, 
physically stable, ecologically functioning streams. When done 
correctly, these projects reduce, ameliorate, or fix unnatural erosion, 
head cutting, and/or sedimentation. Thus, channel restoration projects 
result in geomorphically stable stream channels that maintain the 
appropriate lateral dimensions, longitudinal profiles, and sinuosity 
patterns over time without an aggrading or degrading bed elevation and 
include stable riffle-run-pool complexes that consist of silt-free 
gravel, coarse sand, cobble, boulders, woody structure, and river weed 
(Podostemum ceratophyllum). This provision of the proposed 4(d) rule 
for channel restoration would promote conservation of the coal darter 
by excepting incidental take resulting from activities that would 
improve channel conditions and restore degraded, physically unstable 
streams or stream segments. We anticipate these activities will advance 
ecological conditions within a watershed to a more natural state that 
would benefit the coal darter.
    Streambank Stabilization--Streambank stabilization is used as a 
habitat restoration technique to restore degraded and eroded 
streambanks back to natively vegetated, stable streambanks. When done 
correctly, these projects reduce bank erosion and instream 
sedimentation, resulting in improved habitat conditions for aquatic 
species. Therefore, we would allow streambanks to be stabilized using 
the following bioengineering methods: native live stakes (live, 
vegetative cuttings inserted or tamped into the ground in a manner that 
allows the stake to take root and grow), native live fascines (live 
branch cuttings, usually willows, bound together into long, cigar-
shaped bundles), planting of bare-root seedlings or native brush 
layering (cuttings or branches of easily rooted tree species layered 
between successive lifts of soil fill). All methods should use plant 
species native to the region where the project is being conducted. 
These methods would not include the sole use of quarried rock (riprap) 
or the use of rock baskets or gabion structures, but quarried rock 
(riprap), rock baskets, or gabion structures could be used in 
conjunction with the allowed bioengineering methods described above. 
This provision of the proposed 4(d) rule would promote conservation of 
the coal darter by excepting from the prohibition on incidental take 
those streambank stabilization activities that would improve habitat 
conditions by reducing bank erosion and instream sedimentation.
    Habitat Improvement Activities--Activities that improve watershed, 
riparian, or habitat conditions within the range of the coal darter 
would provide for the conservation of the species. Activities carried 
out under the Working Lands for Wildlife program of the Natural 
Resources Conservation Service, U.S. Department of Agriculture, or 
similar projects, which may include projects funded by the Service's 
Partners for Fish and Wildlife Program or the EPA's 319 grant program, 
would benefit the species if they do not alter habitats known to be 
used by the species beyond its tolerances and are implemented with a 
primary objective of improving environmental conditions to support the 
aquatic biodiversity of flowing water habitats. This provision of the 
proposed 4(d) rule would promote conservation of the coal darter by 
excepting from the prohibition on incidental take those activities 
described above that improve conditions for the species and that would 
likely increase resiliency in the

[[Page 88357]]

Black Warrior, Cahaba, and Coosa Rivers resiliency units.
    Silviculture and Forestry Management Activities--Silviculture and 
forest management activities that use State-approved BMPs to protect 
water and sediment quality and stream and riparian habitat would 
provide for the conservation of the coal darter. Best management 
practices would have to be designed to reduce sedimentation, erosion, 
and bank destruction, thereby protecting instream habitat for the 
species. We recognize that silvicultural operations are widely 
implemented in accordance with State-approved BMPs (as reviewed by 
Cristan et al. 2018, entire), and the adherence to these BMPs broadly 
protects water quality, particularly related to sedimentation (as 
reviewed by Cristan et al. 2016, entire; Warrington et al. 2017, 
entire; Schilling et al. 2021, entire). This provision of the 4(d) rule 
would promote conservation of the coal darter by excepting from the 
prohibition on incidental take those silviculture and forest management 
activities that use State-approved BMPs because this exception would 
allow these activities to continue while protecting the coal darter's 
habitat.
    Despite these prohibitions regarding threatened species, we may 
under certain circumstances issue permits to carry out one or more 
otherwise-prohibited activities, including those described above. The 
regulations that govern permits for threatened wildlife state that the 
Director may issue a permit authorizing any activity otherwise 
prohibited with regard to threatened species. These include permits 
issued for the following purposes: for scientific purposes, to enhance 
propagation or survival, for economic hardship, for zoological 
exhibition, for educational purposes, for incidental taking, or for 
special purposes consistent with the purposes of the Act (50 CFR 
17.32). The statute also contains certain exemptions from the 
prohibitions, which are found in sections 9 and 10 of the Act.
    We recognize the special and unique relationship with our State 
natural resource agency partners in contributing to conservation of 
listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we must cooperate to the 
maximum extent practicable with the states in carrying out programs 
authorized by the Act. Therefore, any qualified employee or agent of a 
State conservation agency that is a party to a cooperative agreement 
with us in accordance with section 6(c) of the Act, who is designated 
by his or her agency for such purposes, would be able to conduct 
activities designed to conserve coal darter that may result in 
otherwise prohibited take without additional authorization.
    Nothing in this proposed 4(d) rule would change in any way the 
recovery planning provisions of section 4(f) of the Act, the 
consultation requirements under section 7 of the Act, or the ability of 
the Service to enter into conservation partnerships for the management 
and protection of the coal darter. However, interagency cooperation may 
be further streamlined through planned programmatic consultations for 
the species between Federal agencies and the Service, where 
appropriate. We ask the public, particularly State agencies and other 
interested stakeholders that may be affected by the proposed 4(d) rule, 
to provide comments and suggestions regarding additional guidance and 
methods that the Service could provide or use, respectively, to 
streamline the implementation of this proposed 4(d) rule (see 
Information Requested, above).

III. Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    We have found critical habitat to be prudent and determinable for 
the coal darter and have developed a proposed critical habitat rule for 
this species. On October 25, 2023, we were informed that the Office of 
Information and Regulatory Affairs (OIRA) in the Office of Management 
and Budget (OMB) determined that our proposed critical habitat rule is 
significant under Executive Order 12866. Therefore, we will publish a 
proposed critical habitat rule for the coal darter following 
interagency review of the proposed critical habitat rule.

Required Determinations

Clarity of the Rule

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

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

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

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), E.O. 13175 (Consultation and Coordination 
with Indian Tribal Governments), and the Department of the Interior's 
manual at

[[Page 88358]]

512 DM 2, we readily acknowledge our responsibility to communicate 
meaningfully with federally recognized Tribes on a government-to-
government basis. In accordance with Secretary's Order 3206 of June 5, 
1997 (American Indian Tribal Rights, Federal-Tribal Trust 
Responsibilities, and the Endangered Species Act), we readily 
acknowledge our responsibilities to work directly with Tribes in 
developing programs for healthy ecosystems, to acknowledge that Tribal 
lands are not subject to the same controls as Federal public lands, to 
remain sensitive to Indian culture, and to make information available 
to Tribes. We have determined that no Tribal lands fall within the 
occupied range of the coal darter, so no Tribes would be affected by 
the listing of the species.

References Cited

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

Authors

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

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

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

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

0
2. In Sec.  17.11, amend paragraph (h) by adding an entry for ``Darter, 
coal'' 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 and
           Common name              Scientific name      Where listed         Status         applicable rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------
                                                     Fishes
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
Darter, coal....................  Percina brevicauda  Wherever found....  T              [Federal Register
                                                                                          citation when
                                                                                          published as a final
                                                                                          rule]; 50 CFR
                                                                                          17.44(ii).\4d\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

0
3. Amend Sec.  17.44 by adding paragraph (ii) to read as follows:


Sec.  17.44  Special rules--fishes.

* * * * *
    (ii) Coal darter (Percina brevicauda).
    (1) Prohibitions. The following prohibitions that apply to 
endangered wildlife also apply to the coal darter. Except as provided 
under paragraph (ii)(2) of this section and Sec. Sec.  17.4 and 17.5, 
it is unlawful for any person subject to the jurisdiction of the United 
States to commit, to attempt to commit, to solicit another to commit, 
or cause to be committed, any of the following acts in regard to this 
species:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken wildlife, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of commercial 
activity, as set forth at Sec.  17.21(e) for endangered wildlife.
    (v) Sale or offer for sale, as set forth at Sec.  17.21(f) for 
endangered wildlife.
    (2) Exceptions from prohibitions. In regard to this species, you 
may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take, as set forth at Sec.  17.31(b).
    (iv) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.
    (v) Take incidental to an otherwise lawful activity caused by:
    (A) Channel restoration projects that create natural, physically 
stable, ecologically functioning streams. These projects can be 
accomplished using a variety of methods, but the desired outcome is a 
natural channel with geomorphically stable stream channels that 
maintain the appropriate lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation and include stable riffle-run-pool complexes that consist of 
silt-free gravel, coarse sand, cobble, boulders, woody structure, and 
river weed (Podostemum ceratophyllum).
    (B) Streambank stabilization projects that use bioengineering 
methods to replace pre-existing, bare, eroding stream banks with 
natively vegetated, stable stream banks, thereby reducing bank erosion 
and instream sedimentation, and improving habitat conditions for the 
coal darter. Stream banks may be stabilized using native live stakes 
(live, vegetative cuttings inserted or tamped into the ground in a 
manner that allows the stake to take root and grow), native live 
fascines (live branch cuttings, usually willows, bound together into 
long, cigar-shaped bundles), planting of bare-root seedlings or native 
brush layering (cuttings or branches of easily rooted tree species 
layered between successive lifts of soil fill). Stream banks must not 
be stabilized solely through the use of quarried rock (riprap) or the 
use of rock baskets or gabion structures.
    (C) Activities that improve the watershed, riparian, or habitat 
conditions for the coal darter within the range of the species. 
Activities carried out under the Working Lands for Wildlife program of 
the Natural Resources Conservation Service, U.S.

[[Page 88359]]

Department of Agriculture, or similar projects, which may include 
projects funded by the Service's Partners for Fish and Wildlife Program 
or the Environmental Protection Agency's 319 grant program, benefit the 
species if they do not alter habitats known to be used by the species 
beyond its tolerances and are implemented with a primary objective of 
improving environmental conditions to support the aquatic biodiversity 
of flowing water habitats.
    (D) Silviculture and forest management activities that use State-
approved best management practices to protect water and sediment 
quality and stream and riparian habitat. Best management practices must 
be designed to reduce sedimentation, erosion, and bank destruction, 
thereby protecting instream habitat for the coal darter.

Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2023-27873 Filed 12-20-23; 8:45 am]
BILLING CODE 4333-15-P