[Federal Register Volume 86, Number 110 (Thursday, June 10, 2021)]
[Proposed Rules]
[Pages 30888-30909]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11966]



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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2018-0021; FF09E21000 FXES11110900000 212]
RIN 1018-BD55


Endangered and Threatened Wildlife and Plants; Designating Texas 
Hornshell Critical Habitat

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 
designate critical habitat for the Texas hornshell (Popenaias popeii), 
a freshwater mussel, under the Endangered Species Act (Act). In total, 
the proposed critical habitat designation includes approximately 463.6 
river miles (745.9 kilometers) in Eddy County, New Mexico, and in 
Culberson, Brewster, Terrell, Val Verde, Kinney, Maverick, and Webb 
Counties, Texas. If we finalize this rule as proposed, it would extend 
the Act's protections to this species' critical habitat. The effect of 
this regulation is to designate critical habitat for the Texas 
hornshell under the Act. We also announce the availability of a draft 
economic analysis of the proposed designation of critical habitat. We 
also are notifying the public that we have scheduled an informational 
meeting followed by a public hearing on the proposed rule.

DATES: 
    Comment submission: We will accept comments on this proposed rule 
or draft economic analysis that are received or postmarked on or before 
August 9, 2021. 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.
    Public informational meeting and public hearing: We will hold a 
public informational session from 5:00 p.m. to 6:00 p.m., Mountain 
Time, followed by a public hearing from 6:30 p.m. to 8:30 p.m., 
Mountain Time, on June 29, 2021.

ADDRESSES: 
    Comment submission: You may submit comments on the proposed rule or 
draft economic analysis by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: http://www.regulations.gov. In the Search box, enter FWS-R2-ES-2018-0021 to 
find this proposed rule. You may submit a comment by clicking on 
``Comment Now!''
    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R2-ES-2018-0021; U.S. Fish and Wildlife Service 
Headquarters, MS: BPHC, 5275 Leesburg Pike, Falls Church, VA 22041-
3803.
    We request that you send comments only by the methods described 
above. We will post all comments on http://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see the Information Requested section below for more information).
    Public informational meeting and public hearing: The public 
informational meeting and the public hearing will be held virtually 
using the Zoom platform. See Public Hearing, below, for more 
information.
    Document availability: The draft economic analysis is available at 
https://www.fws.gov/southwest/es/TexasCoastal/, at http://www.regulations.gov in Docket No. FWS-R2-ES-2018-0021, and at the Texas 
Coastal Ecological Services Field Office (see FOR FURTHER INFORMATION 
CONTACT).
    The coordinates or plot points or both from which the maps are 
generated are included in the administrative record for this critical 
habitat designation and are available at https://www.fws.gov/southwest/es/TexasCoastal/, at http://www.regulations.gov in Docket No. FWS-R2-
ES-2018-0021, and at the Texas Coastal Ecological Services Field Office 
(see FOR FURTHER INFORMATION CONTACT). Any additional tools or 
supporting information that we may develop for this critical habitat 
designation will also be available at the Service website and field 
office set out above, and may also be included in the preamble of the 
final rule and/or at http://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Chuck Ardizzone, U.S. Fish and 
Wildlife Service, Texas Coastal Ecological Services Field Office, 17629 
El Camino Real #211, Houston, TX 77058; by telephone 281-286-8282; or 
by facsimile 281-488-5882. Persons who use a telecommunications device 
for the deaf (TDD) may call the Federal Relay Service at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Endangered Species Act, 
critical habitat must be designated, to the maximum extent prudent and 
determinable, for all species determined to be endangered or 
threatened. The Lists of Endangered and Threatened Wildlife and Plants 
are in title 50 of the Code of Federal Regulations (CFR) in part 17 (50 
CFR 17.11(h) for wildlife and 50 CFR 17.12(h) for plants). Designations 
and revisions of critical habitat can only be completed by issuing a 
rule.
    What this document does. This document proposes the designation of 
critical habitat for the Texas hornshell and announces the availability 
of the draft economic analysis. The Texas hornshell has been listed as 
an endangered species under the Act. This rule proposes designation of 
critical habitat necessary for the conservation of the species.
    The basis for our action. Under the Endangered Species Act, any 
species that is determined to be a threatened or endangered species 
shall, to the maximum extent prudent and determinable, have habitat 
designated that is considered to be critical habitat. Section 4(b)(2) 
of the Endangered Species Act states that the Secretary shall designate 
and make revisions to critical habitat on the basis of the best 
available scientific data after taking into consideration the economic 
impact, the impact on national security, and any other relevant impact 
of specifying any particular area as critical habitat. The Secretary 
may exclude an area from critical habitat if he determines that the 
benefits of such exclusion outweigh the benefits of specifying such 
area as part of the critical habitat, unless he determines, based on 
the best scientific data available, that the failure to designate such 
area as critical habitat will result in the extinction of the species.
    Supporting analyses. We prepared an analysis of the economic 
impacts of the proposed critical habitat designation and hereby 
announce the availability of the draft economic analysis for public 
review and comment.
    Our species status assessment report (SSA report) documents the 
results of the comprehensive biological status review for the Texas 
hornshell and provides an account of the species' overall viability 
through forecasting of the species' condition in the future (Service 
2018, entire). Additionally, the SSA report contains our analysis of 
required habitat and the existing conditions of that habitat.
    Peer review. We sought comments from independent specialists on the 
SSA report to ensure that our critical habitat proposal is based on 
scientifically sound data and analyses. We received feedback from four 
scientists with expertise in freshwater mussel biology, ecology, and 
genetics as peer review of the SSA report. The reviewers were generally 
supportive of

[[Page 30889]]

our approach and made suggestions and comments that strengthened our 
analysis. We incorporated these comments into the SSA report, which can 
be found at http://www.regulations.gov under Docket No. FWS-R2-ES-2018-
0021.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific data available and be as accurate 
and as effective as possible. Therefore, we request comments or 
information from other concerned government agencies, the scientific 
community, industry, or any other interested party concerning this 
proposed rule. Because we will consider all comments and information 
received during the comment period, our final determinations may differ 
from this proposal.
    We particularly seek comments concerning:
    (1) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act (16 U.S.C. 1531 et 
seq.) including information to inform the following factors such that a 
designation of critical habitat may be determined to be not prudent:
    (a) The species is threatened by taking or other human activity and 
identification of critical habitat can be expected to increase the 
degree of such threat to the species;
    (b) The present or threatened destruction, modification, or 
curtailment of a species' habitat or range is not a threat to the 
species, or threats to the species' habitat stem solely from causes 
that cannot be addressed through management actions resulting from 
consultations under section 7(a)(2) of the Act;
    (c) Areas within the jurisdiction of the United States provide no 
more than negligible conservation value, if any, for a species 
occurring primarily outside the jurisdiction of the United States;
    (d) No areas meet the definition of critical habitat.
    (2) Specific information on:
    (a) The amount and distribution of Texas hornshell habitat;
    (b) What areas that were occupied at the time of listing and that 
contain the physical or biological features essential to the 
conservation of the species should be included in the designation and 
why;
    (c) Special management considerations or protection that may be 
needed in critical habitat areas we are proposing, including managing 
for the potential effects of climate change; and
    (d) What areas not occupied at the time of listing are essential 
for the conservation of the species. We particularly seek comments 
regarding:
    (i) Whether occupied areas are inadequate for the conservation of 
the species; and,
    (ii) Specific information that supports the determination that 
unoccupied areas will, with reasonable certainty, contribute to the 
conservation of the species and, contain at least one physical or 
biological feature essential to the conservation of the species.
    (3) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (4) Information on the projected and reasonably likely impacts of 
climate change on the Texas hornshell and proposed critical habitat.
    (5) Any probable economic, national security, or other relevant 
impacts of designating any area that may be included in the final 
designation, and the benefits of including or excluding areas that may 
be impacted.
    (6) Information on the extent to which the description of probable 
economic impacts in the draft economic analysis is a reasonable 
estimate of the likely economic impacts.
    (7) Whether any specific areas we are proposing for critical 
habitat designation should be considered for exclusion under section 
4(b)(2) of the Act, and whether the benefits of potentially excluding 
any specific area outweigh the benefits of including that area under 
section 4(b)(2) of the Act, in particular for those covered by the 
Candidate Conservation Agreement (CCA) and Candidate Conservation 
Agreement with Assurances (CCAA) for the Texas hornshell in the Black 
and Delaware Rivers in New Mexico and Texas.
    (8) Whether any lands should be considered for exclusion under 
section 4(b)(2) of the Act for national security reasons, whether such 
exclusion is or is not appropriate, and whether the benefits of 
excluding any specific area outweigh the benefits of including that 
area as critical habitat and why.
    (9) Whether lands owned by the Kickapoo Indian Reservation of Texas 
should be considered for exclusion under section 4(b)(2) of the Act, 
whether such exclusion is or is not appropriate, and whether the 
benefits of excluding any specific area outweigh the benefits of 
including that area as critical habitat and why.
    (10) The likelihood of adverse social reactions to the designation 
of critical habitat, as discussed in the associated documents of the 
draft economic analysis, and how the consequences of such reactions, if 
likely to occur, would relate to the conservation and regulatory 
benefits of the proposed critical habitat designation.
    (11) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments.
    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.
    All comments submitted electronically via http://www.regulations.gov will be presented on the website in their entirety 
as submitted. For comments submitted via hard copy, we will post your 
entire comment--including your personal identifying information--on 
http://www.regulations.gov. You may request at the top of your document 
that we withhold personal information such as your street address, 
phone number, or email address from public review; however, we cannot 
guarantee that we will be able to do so.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on http://www.regulations.gov.

Previous Federal Actions

    All previous Federal actions are described in the final rule 
listing the Texas hornshell as an endangered species under the Act 
published in the Federal Register on February 9, 2018 (83 FR 5720).

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.

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    Our regulations at 50 CFR 424.02 define the geographical area 
occupied by the species as: An area that may generally be delineated 
around species' occurrences, as determined by the Secretary (i.e., 
range). Such areas may include those areas used throughout all or part 
of the species' life cycle, even if not used on a regular basis (e.g., 
migratory corridors, seasonal habitats, and habitats used periodically, 
but not solely by vagrant individuals).
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the destruction or adverse modification of 
critical habitat. The designation of critical habitat does not affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. Such designation does not allow the government 
or public to access private lands. Such designation does not require 
implementation of restoration, recovery, or enhancement measures by 
non-Federal landowners. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the consultation requirements of section 7(a)(2) 
of the Act would apply, but even in the event of a destruction or 
adverse modification finding, the obligation of the Federal action 
agency and the landowner is not to restore or recover the species, but 
to implement reasonable and prudent alternatives to avoid destruction 
or adverse modification of critical habitat.
    Under the first prong of the Act's definition of critical habitat, 
areas within the geographical area occupied by the species at the time 
it was listed are included in a critical habitat designation if they 
contain physical or biological features (1) Which are essential to the 
conservation of the species and (2) which may require special 
management considerations or protection. For these areas, critical 
habitat designations identify, to the extent known using the best 
scientific and commercial data available, those physical or biological 
features that are essential to the conservation of the species (such as 
space, food, cover, and protected habitat). In identifying those 
physical or biological features that occur in specific areas, we focus 
on the specific features that are essential to support the life-history 
needs of the species, including but not limited to, water 
characteristics, soil type, geological features, prey, vegetation, 
symbiotic species, or other features. A feature may be a single habitat 
characteristic, or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity.
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species. When designating critical habitat, the Secretary will first 
evaluate areas occupied by the species. The Secretary will only 
consider unoccupied areas to be essential where a critical habitat 
designation limited to geographical areas occupied by the species would 
be inadequate to ensure the conservation of the species. In addition, 
for an unoccupied area to be considered essential, the Secretary must 
determine that there is a reasonable certainty both that the area will 
contribute to the conservation of the species and that the area 
contains one or more of those physical or biological features essential 
to the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines, provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 
habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information from the SSA report and information developed during the 
listing process for the species. Additional information sources may 
include any generalized conservation strategy, criteria, or outline 
that may have been developed for the species, the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, other unpublished materials, or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. We recognize that critical habitat designated at a 
particular point in time may not include all of the habitat areas that 
we may later determine are necessary for the recovery of the species. 
For these reasons, a critical habitat designation does not signal that 
habitat outside the designated area is unimportant or may not be needed 
for recovery of the species. Areas that are important to the 
conservation of the species, both inside and outside the critical 
habitat designation, will continue to be subject to: (1) Conservation 
actions implemented under section 7(a)(1) of the Act, (2) regulatory 
protections afforded by the requirement in section 7(a)(2) of the Act 
for Federal agencies to ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species, and (3) section 9 of the Act's prohibitions on taking any 
individual of the species, including taking caused by actions that 
affect habitat. Federally funded or permitted projects affecting listed 
species outside their designated critical habitat areas may still 
result in findings that the action jeopardizes the continued existence 
of the species in some cases. These protections and conservation tools 
will continue to contribute to recovery of this species. Similarly, 
critical habitat designations made on the basis of the best available 
information at the time of designation will not control the direction 
and substance of future recovery plans, habitat conservation plans, or 
other species conservation planning efforts if new information

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available at the time of these planning efforts calls for a different 
outcome.
Habitat Outside the United States
    Within the identified geographical area occupied at the time of 
listing (see below, Areas Occupied at the Time of Listing), the habitat 
areas used by the species are in Texas, New Mexico, and Mexico. Because 
we do not designate as critical habitat areas outside the United States 
(50 CFR 424.12(g)), we did not examine areas on the Mexican side of the 
Rio Grande; the critical habitat extends only as far into the river as 
the United States' jurisdictional boundary, i.e., to the middle of the 
river. However, conservation of habitat that meets the conditions 
described in this designation in Mexico may be important to recovery of 
the species.

Prudency Determination

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12), require that, to the maximum extent 
prudent and determinable, the Secretary shall designate critical 
habitat at the time the species is determined to be an endangered or 
threatened species. Our regulations (50 CFR 424.12(a)(1)) state that 
the Secretary may, but is not required to, determine that a designation 
would not be prudent in the following circumstances:
    (i) The species is threatened by taking or other human activity and 
identification of critical habitat can be expected to increase the 
degree of such threat to the species;
    (ii) The present or threatened destruction, modification, or 
curtailment of a species' habitat or range is not a threat to the 
species, or threats to the species' habitat stem solely from causes 
that cannot be addressed through management actions resulting from 
consultations under section 7(a)(2) of the Act;
    (iii) Areas within the jurisdiction of the United States provide no 
more than negligible conservation value, if any, for a species 
occurring primarily outside the jurisdiction of the United States;
    (iv) No areas meet the definition of critical habitat; or
    (v) The Secretary otherwise determines that designation of critical 
habitat would not be prudent based on the best scientific data 
available.
    We did not identify any of the factors above to apply to the Texas 
hornshell. Therefore, we find designation of critical habitat is 
prudent for the species.

Critical Habitat Determinability

    Having determined that designation is prudent, under section 
4(a)(3) of the Act we must find whether critical habitat for the Texas 
hornshell is determinable. Our regulations at 50 CFR 424.12(a)(2) state 
that critical habitat is not determinable when one or both of the 
following situations exist:
    (i) Data sufficient to perform required analyses are lacking, or
    (ii) The biological needs of the species are not sufficiently well 
known to identify any area that meets the definition of ``critical 
habitat.''
    When critical habitat is not determinable, the Act allows the 
Service an additional year to publish a critical habitat designation 
(16 U.S.C. 1533(b)(6)(C)(ii)).
    At the time of our August 10, 2016, proposed rule to list the 
species, we found that critical habitat was not determinable due to 
insufficient knowledge of the biological needs of the species. We have 
continued to review the available information related to the Texas 
hornshell and newly acquired information necessary to perform this 
assessment, and we reviewed the available information pertaining to the 
biological needs of the species and habitat characteristics where this 
species is located. We examined collection reports and occupancy models 
for the Texas hornshell (Randklev et al. 2017, entire). Additionally, 
we prepared a draft economic analysis. This and other information 
represent the best scientific data available and led us to conclude 
that the designation of critical habitat is determinable for the Texas 
hornshell.

Physical or Biological Features

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12(b), in determining which areas within the geographical 
area occupied by the species at the time of listing to designate as 
critical habitat, we consider the physical or biological features that 
are essential to the conservation of the species and which may require 
special management considerations or protection. The regulations at 50 
CFR 424.02 define ``physical or biological features essential to the 
conservation of the species'' as the features that occur in specific 
areas and that are essential to support the life-history needs of the 
species, including but not limited to, water characteristics, soil 
type, geological features, sites, prey, vegetation, symbiotic species, 
or other features. A feature may be a single habitat characteristic, or 
a more complex combination of habitat characteristics. Features may 
include habitat characteristics that support ephemeral or dynamic 
habitat conditions. Features may also be expressed in terms relating to 
principles of conservation biology, such as patch size, distribution 
distances, and connectivity. For example, physical features might 
include gravel of a particular size required for spawning, alkaline 
soil for seed germination, protective cover for migration, or 
susceptibility to flooding or fire that maintains necessary early-
successional habitat characteristics. Biological features might include 
prey species, forage grasses, specific kinds or ages of trees for 
roosting or nesting, symbiotic fungi, or a particular level of 
nonnative species consistent with conservation needs of the listed 
species.
    The features may also be combinations of habitat characteristics 
and may encompass the relationship between characteristics or the 
necessary amount of a characteristic needed to support the life history 
of the species. In considering whether features are essential to the 
conservation of the species, the Service may consider an appropriate 
quality, quantity, and spatial and temporal arrangement of habitat 
characteristics in the context of the life-history needs, condition, 
and status of the species. These characteristics include, but are not 
limited to space for individual and population growth and for normal 
behavior; food, water, air, light, minerals, or other nutritional or 
physiological requirements; cover or shelter; sites for breeding, 
reproduction, or rearing (or development) of offspring; and habitats 
that are protected from disturbance.
Space for Individual and Population Growth and for Normal Behavior
    Most freshwater mussels, including Texas hornshell, are found in 
aggregations, called mussel beds, that vary in size from about 50 to 
greater than 5,000 square meters (m\2\), separated by stream reaches in 
which mussels are absent or rare (Vaughn 2012, p. 983). Texas hornshell 
larvae (called glochidia) are parasites that must attach to a host fish 
(generally river carpsucker (Carpiodes carpio), grey redhorse 
(Moxostoma congestum), and red shiner (Cyprinella lutrensis)). A 
population of Texas hornshell incorporates more than one mussel bed; it 
is the collection of mussel beds within a stream reach between which 
infested host fish may travel, allowing for ebbs and flows in mussel 
bed density and abundance over time throughout the population's 
occupied reach. Therefore, resilient

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Texas hornshell populations must occupy stream reaches long enough so 
that stochastic events that affect individual mussel beds do not 
eliminate the entire population. Repopulation by infested host fish 
from other mussel beds within the reach can allow the population to 
recover from these events. Longer stream reaches are more likely to 
support populations of Texas hornshell into the future than shorter 
stream reaches. Therefore, we determine that long stream reaches are an 
important component of a riverine system with habitat to support all 
life stages of Texas hornshell.
    Texas hornshell need flowing water for survival. They are not found 
in lakes or in pools without flow, or in areas that are regularly 
dewatered. River reaches with continuous flow support all life stages 
of Texas hornshell, while those with little or no flow do not. Flow 
rates needed by the species will vary depending on river size, 
location, and substrate type.
    Additionally, Texas hornshell occur in flow refuges such as 
crevices, undercut riverbanks, travertine shelves, and large boulders. 
These refuges must have seams of clay or other fine sediments within 
which the mussels may anchor, but not so much excess sediment that the 
mussels are smothered. Those areas with clean-swept substrate 
(substrate not covered in sediment) with seams of fine sediments in 
crevices are suitable Texas hornshell habitat, as well as habitat for 
their host fish.
Physiological Requirements: Water Quality Requirements
    Freshwater mussels, as a group, are sensitive to changes in water 
quality parameters such as dissolved oxygen, salinity, ammonia, and 
pollutants. Habitats with appropriate levels of these parameters are 
considered suitable, while those habitats with levels outside of the 
appropriate ranges are considered less suitable. We have used 
information available for other species of freshwater mussels to inform 
the needs of Texas hornshell. Juvenile freshwater mussels are 
particularly susceptible to low dissolved oxygen levels. Juveniles will 
reduce feeding behavior when dissolved oxygen is between 2-4 milligrams 
per liter (mg/L), and mortality has been shown to occur at dissolved 
oxygen levels below 1.3 mg/L. Additionally, Texas hornshell will die at 
salinity levels of 7 parts per thousand (ppt) for more than several 
weeks (Lang 2001, pp. 10-11). Juvenile mussels of other species have 
been shown to experience complete mortality after 7 days at salinity 
levels greater than 4 ppt (Blakeslee et al. 2013, p. 2851)
    The release of pollutants into streams from point and nonpoint 
sources have immediate impacts on water quality conditions and may make 
environments unsuitable for habitation by mussels. Early life stages of 
freshwater mussels are some of the most sensitive organisms of all 
species to ammonia and copper (Naimo 1995, pp. 351-352; Augsperger et 
al. 2007, p. 2025). Additionally, sublethal effects of contaminants 
over time can result in reduced feeding efficiency, reduced growth, 
decreased reproduction, changes in enzyme activity, and behavioral 
changes to all mussel life stages. Even wastewater discharges with low 
ammonia levels have been shown to negatively affect mussel populations. 
Therefore, we determine that stream reaches with the following water 
quality parameters are suitable for Texas hornshell:

<bullet> Low salinity (less than 0.9 ppt)
<bullet> Low ammonia (less than 0.7 mg/L)
<bullet> Low levels of contaminants
<bullet> Dissolved oxygen levels within substrate greater than 1.3 mg/
L.
Sites for Development of Offspring
    As discussed above, Texas hornshell larvae are parasites that must 
attach to a host fish to develop into juvenile mussels. Texas hornshell 
primarily use river carpsucker, gray redhorse, and red shiner as hosts. 
The river carpsucker and red shiner are widespread throughout the Texas 
hornshell's occupied range (Hubbs 1990, pp. 90-91; Levine et al. 2012, 
p. 1857). The presence of these fish species, either singly or in 
combination, supports the life-history needs of the Texas hornshell.

Summary of Essential Physical or Biological Features

    We derive the specific physical or biological features essential to 
the conservation of the Texas hornshell from studies of this species' 
habitat, ecology, and life history as described below. Additional 
information can be found in the final listing rule published in the 
Federal Register on February 9, 2018 (83 FR 5720), and the Species 
Status Assessment for the Texas Hornshell (Service 2018, entire). We 
have determined that the following physical or biological features are 
essential to the conservation of the Texas hornshell:
    A riverine system with habitat to support all life stages of the 
Texas hornshell, which includes:
    (a) Flowing water at rates high enough to support clean-swept 
substrate but not so high as to dislodge individuals;
    (b) Crevices beneath boulders, shelves, and within undercut banks 
with seams of fine sediment;
    (c) River carpsucker, red shiner, and gray redhorse present; and
    (d) Water quality parameters within the following ranges:
    (i) Salinity below 0.9 ppt;
    (ii) Ammonia below 0.7 mg/L;
    (iii) Low levels of contaminants; and
    (iv) Dissolved oxygen levels within substrate greater than 1.3mg/L.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features that are essential to the conservation of 
the species and which may require special management considerations or 
protection. The features essential to the conservation of this species 
may require special management considerations or protection to reduce 
the following threats: Increased fine sediment, water quality 
impairment, loss of flowing water, and barriers to fish movement.
    Management activities that could ameliorate these threats and 
protect the integrity of the stream ecosystem include restoring or 
maintaining the natural hydrology of the stream, removing livestock 
from Texas hornshell habitats, preventing chemical spills, and 
appropriately maintaining bridges and other stream crossings to limit 
sediment input.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available to designate critical habitat. In accordance 
with the Act and our implementing regulations at 50 CFR 424.12(b), we 
review available information pertaining to the habitat requirements of 
the species and identify specific areas within the geographical area 
occupied by the species at the time of listing and any specific areas 
outside the geographical area occupied by the species to be considered 
for designation as critical habitat. We are not currently proposing to 
designate any areas outside the geographical area occupied by the 
species at the time of listing in February 2018.
    The SSA report contains much of the information used to identify 
critical habitat for Texas hornshell, which includes existing State 
recovery plans, numerous survey reports on streams

[[Page 30893]]

throughout the species' range, and museum records of historical 
locations (Service 2018).

Areas Occupied at the Time of Listing

    The proposed critical habitat designation does not include all 
streams known to have been occupied by the species historically; 
instead, it focuses on occupied streams within the historical range 
that have retained the necessary physical and biological features 
(PBFs) that will allow for the maintenance and expansion of existing 
populations. The following streams meet the definition of areas 
occupied by the species at the time of listing: Black River, Delaware 
River, Pecos River, Devils River, and Rio Grande. No developed areas 
occur within the proposed designation except for road crossings of 
streams, which do not remove the suitability of these areas for this 
species, because habitat is still present.
    In summary, for areas proposed as critical habitat, we delineated 
critical habitat unit boundaries using the following criterion: 
Evaluate habitat suitability of stream segments within the geographic 
area occupied at the time of listing, and delineate those segments that 
contain some or all of the PBFs to support life-history functions 
essential for conservation of the species.
    As a final step, we evaluated those occupied stream segments 
identified through the above analysis and refined the starting and 
ending points by evaluating the presence or absence of appropriate 
PBFs. We selected upstream and downstream cutoff points to omit areas 
that are highly degraded and are not likely to support the Texas 
hornshell. For example, permanently dewatered areas or areas in which 
there was a change to unsuitable parameters (e.g., water quality, 
bedrock substrate) were used to mark the start or endpoint of a stream 
segment proposed for designation. Critical habitat stream segments were 
then mapped using ArcMap version 10 (Environmental Systems Research 
Institute, Inc.), a Geographic Information Systems program.
    The areas proposed for designation as critical habitat provide 
sufficient stream habitat for adult Texas hornshell, as well as for the 
habitat needs for juveniles and the fish species that serve as hosts 
for the Texas hornshell's parasitic larvae. In general, the PBFs of 
critical habitat are contained within the riverine ecosystem formed by 
the channel at bankfull stage. Texas hornshell use the riverine 
ecosystem for feeding, breeding, and sheltering.
    When determining proposed critical habitat boundaries, we made 
every effort to avoid including developed areas such as lands covered 
by buildings, pavement, and other structures because such lands lack 
physical or biological features necessary for the Texas hornshell. The 
scale of the maps we prepared under the parameters for publication 
within the Code of Federal Regulations may not reflect the exclusion of 
such developed lands. Any such lands inadvertently left inside critical 
habitat boundaries shown on the maps of this proposed rule have been 
excluded by text in the proposed rule and are not proposed for 
designation as critical habitat. Therefore, if the critical habitat is 
finalized as proposed, a Federal action involving these lands would not 
trigger section 7 consultation with respect to critical habitat and the 
requirement of no adverse modification unless the specific action would 
affect the physical or biological features in the adjacent critical 
habitat.
    We are proposing for designation of critical habitat river miles 
that we have determined were occupied at the time of listing and 
contain one or more of the physical or biological features that are 
essential to support life-history processes of the species.
    The critical habitat designation is defined by the maps, as 
modified by any accompanying regulatory text, presented at the end of 
this document in the rule portion. We include more detailed information 
on the boundaries of the critical habitat designation in the preamble 
of this document. We will make the coordinates or plot points or both 
on which each map is based available to the public on http://www.regulations.gov at Docket No. FWS-R2-ES-2017-0030, on our internet 
site (https://www.fws.gov/southwest/es/TexasCoastal/), and at the field 
office responsible for the designation (see FOR FURTHER INFORMATION 
CONTACT above).

Proposed Critical Habitat Designation

    We are proposing to designate 463.6 mi (745.9 km) in five units as 
critical habitat for Texas hornshell. The critical habitat areas we 
describe below constitute our current best assessment of areas that 
meet the definition of critical habitat for Texas hornshell. The five 
areas we propose as critical habitat are: (1) Pecos Tributary Unit; (2) 
Pecos River Unit; (3) Devils River Unit; (4) Rio Grande--Lower Canyons 
Unit; and (5) Rio Grande--Laredo Unit. Table 1 shows the occupancy of 
the units, the land ownership, and approximate areas of the proposed 
designated areas for the Texas hornshell.

                      Table 1--Occupancy, Land Ownership, and Size of Texas Hornshell Proposed Critical Habitat Units and Subunits
                                         [BLM = Bureau of Land Management; NGO = non-governmental organization]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                              Occupancy at time of
                Unit                         Subunit                 listing           Current occupancy      Riparian ownership            Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
1--Pecos Tributary.................  1a--Black River.......  Occupied..............  Occupied.............  Private..............  9.7 mi (15.6 km).
                                     1b--Delaware River....  Occupied..............  Occupied.............  BLM, Private.........  31.1 mi (50.0 km).
2--Pecos River.....................  ......................  Occupied..............  Occupied.............  Private, Federal, NGO  85.7 mi (137.9 km).
3--Devils River....................  ......................  Occupied..............  Occupied.............  Federal, Private,      33.0 mi (53.1 km).
                                                                                                             NGO, State.
4--Rio Grande--Lower Canyons.......  4a--Lower Canyons       Occupied..............  Occupied.............  Federal, State.......  66.7 mi (107.3 km).
                                      Reach.
                                     4b--Langtry Reach.....  Occupied..............  Occupied.............  Private, Federal.....  46.5 mi (74.8 km).
5--Rio Grande--Laredo..............  5a--Eagle Pass Reach..  Occupied..............  Occupied.............  Private, City, Tribal  138.7 mi (223.2 km).
                                     5b--Laredo Reach......  Occupied..............  Occupied.............  Private, City........  52.2 mi (84.0 km).
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 30894]]

    We present brief descriptions of all units, and reasons why they 
meet the definition of critical habitat for Texas hornshell, below.

Unit 1: Pecos Tributary Unit

    Subunit 1a: Black River: Subunit 1a consists of 15.6 km (9.7 mi) in 
private ownership in Eddy County, New Mexico. The Texas hornshell 
occupies the entire stream in this subunit, and the subunit contains 
all of the PBFs essential to the conservation of Texas hornshell. The 
watershed of the Black River is characterized by rural ranching and 
farming, as well as oil and gas development. Diverted river water and 
groundwater are used for irrigation of farms and ranches as well as 
hydraulic fracturing by oil and gas development operations (Bren School 
of Environmental Management 2014, pp. 32, 130). Additionally, only a 
few roads cross the Black River at low-water crossings; therefore, 
traffic, including local and industrial, is concentrated in these 
areas. The relatively short length of this reach renders the population 
more susceptible to stochastic events. Consequently, special management 
may be necessary to ensure perennial flow in the river, prevent 
contaminant spills, and reduce livestock access to the river.
    The Service has collaborated with water users, oil and gas 
developers, landowners, and other partners to develop a Candidate 
Conservation Agreement (CCA) and Candidate Conservation Agreements with 
Assurances (CCAAs) for the species on State, Federal, and private 
lands. The purpose of these agreements is to provide voluntary 
conservation that would reduce threats to the species while improving 
physical habitat and water quality. The key conservation measures in 
the agreements are designed to limit oil and gas development to areas 
outside of the Black and Delaware River floodplains, minimize erosion, 
and maintain minimum water flows in the rivers. Along with these 
measures, the partners to the agreement are evaluating alternatives to 
the multiple low water crossings on the Black River. Partners are 
considering alternate crossing locations that could include bridges 
designed to allow host fishes to pass through in addition to decreasing 
potential contamination events. We are considering excluding the 
subunit under section 4(b)(2) of the Act if these agreements are 
implemented in a manner sufficient to defray the need for additional 
special management.
    Subunit 1b: Delaware River: Subunit 1b consists of 50.0 km (31.1 
mi) of occupied habitat in the Delaware River in Culberson County, 
Texas, and Eddy County, New Mexico. Texas hornshell were historically 
known from dead shells found within this subunit; the species was 
likely extirpated due to lack of water. Habitat improvements undertaken 
by the Bureau of Land Management (BLM) resulted in perennial flow 
through the rehabilitated section of the Delaware River (BLM 2005, p. 
1). A total of 126 adult Texas hornshell were reintroduced to the river 
in New Mexico in 2014 and 2015. The reintroduced adults were recaptured 
alive and the females were gravid (brooding larvae) in 2016, indicating 
preliminary success. A spill of 11 barrels of oil and 18,000 barrels of 
water that has been collected as a byproduct of oil and gas production 
occurred upstream of the reintroduced individuals in August 2017; the 
effects of this spill and the subsequent flooding has resulted in only 
two of the reintroduced individuals still remaining in the Delaware 
River. The New Mexico Department of Game and Fish plan to continue 
their reintroduction efforts to ensure a diverse, reproducing 
population persists in the river; successful freshwater mussel 
reintroductions typically require multiple years of effort. Riparian 
ownership consists of the BLM and private landowners. The BLM helped 
restore perennial flow to the river through riparian management, and 
now the reach contains all of the PBFs essential to the conservation of 
Texas hornshell.
    The Delaware River is included in the CCA/CCAA described in Subunit 
1a; therefore, we are considering it for exclusion under section 
4(b)(2) of the Act.

Unit 2: Pecos River Unit

    This unit consists of 137.9 km (85.7 mi) in private, non-
governmental organization (NGO), and Federal ownership of the Pecos 
River in Val Verde and Terrell Counties, Texas. This unit is occupied. 
Three live Texas hornshell were collected from the Pecos River Unit in 
2016, which, based on species survey efforts, indicates several other 
living Texas hornshell were likely in the unit at that time. In 
addition, the 2016 collection resulted in numerous shells of the Texas 
hornshell (Bosman et al. 2016, p. 6; Randklev et al. 2016, p. 9), which 
is further evidence that additional members of the species were in the 
Pecos River. The live specimens collected in 2016 were very old, but we 
have no indication that they were no longer occupying the Pecos River 
at the time of listing. The direct evidence of multiple living 
specimens of Texas hornshell in the Pecos River as recently as 2016, 
along with the conclusion that other members of the species were likely 
present at that time, allows us to conclude that the Pecos River Unit 
was occupied at the time of listing. This unit contains some of the 
PBFs essential to the conservation of Texas hornshell, such as flowing 
water and adequate crevices, but salinity is relatively high in this 
unit, compromising water quality. Special management may be necessary 
to improve water quality in this reach.

Unit 3: Devils River Unit

    This unit consists of 53.1 km (33.0 mi) of the Devils River in Val 
Verde County, Texas. Riparian lands are primarily in private ownership, 
including The Nature Conservancy (TNC), and both the Texas Parks and 
Wildlife Department (TPWD) and the Federal Government owns portions of 
these lands. Texas hornshell are historically known from the Devils 
River and currently occupy the unit. The Devils River represents a 
relatively intact watershed, with no dams, little development, and much 
of it under conservation management. Texas hornshell sites are located 
on Dolan Falls Preserve, which is 4,800 acres (ac) (1,943 hectares 
(ha)) owned by TNC, as well as an additional 13,722 ac (5,553 ha) 
managed under a conservation easement. TNC also owns Nix 2 Ranch 
(87,000 ac (35,209 ha)), and TPWD owns the Devils River State Natural 
Area (37,000 ac (15,000 ha)), resulting in conservation management of 
much of the land along the river (TNC 2004, p. 9; TPWD 2016, p. 1). The 
PBFs essential to the conservation of Texas hornshell are present in 
the Devils River. Special management may be necessary to maintain 
instream flows in the river.

Unit 4: Rio Grande--Lower Canyons

    Subunit 4a: Lower Canyons Reach: This subunit consists of 107.3 km 
(66.7 mi) of occupied habitat on the U.S. side of the Rio Grande in 
Terrell and Brewster Counties, Texas. Most of this reach is part of the 
Rio Grande Wild and Scenic River, owned by the United States and 
managed by the National Park Service. A small portion of the subunit is 
owned by the State of Texas. The PBFs essential to the conservation of 
Texas hornshell are present in this subunit. It was designated a 
National Wild and Scenic River in 1978 (Garrett and Edwards 2004, p. 
396), which affords some protection from Federal development projects, 
but does not limit State, local, or private development (National Wild 
and Scenic Rivers System 2016, p. 1). Special management

[[Page 30895]]

may be necessary to maintain instream flows in the river.
    Subunit 4b: Langtry Reach: This subunit consists of 74.8 km (46.5 
mi) of the U.S. side of the Rio Grande in Terrell and Val Verde 
Counties, Texas, most of which is also owned and managed by the 
National Park Service. A small portion of this subunit is in private 
ownership. This unit contains all of the PBFs and is connected to the 
known population of Texas hornshell in Subunit 4a, but the remote 
nature of this reach has prevented surveys. There are no instream 
structures in Subunit 4b that would impede water flow; the flow regime 
is the same as in Subunit 4a; and the host fish may move between the 
subunits freely. Based on this information, it is reasonable to 
conclude that that the population in Subunit 4a is unlikely to stop at 
the most downstream survey location; therefore, we conclude this 
subunit is occupied.
    However, due to the lack of recent surveys, we are analyzing this 
subunit against the second prong of the definition of critical habitat 
for unoccupied habitat out of an abundance of caution. If Subunit 4b is 
not, in fact, occupied, it would provide for needed growth and 
expansion of the species in this portion of its historical range. The 
longer the occupied reach, the more likely it is that the Texas 
hornshell population can withstand stochastic events such as extreme 
flooding, dewatering, or water contamination. Therefore, Subunit 4b is 
essential for the conservation of the species.
    Like Subunit 4a, this subunit is part of the Rio Grande Wild and 
Scenic River, which affords some protection from Federal development 
projects, but does not limit State, local, or private development 
(National Wild and Scenic Rivers System 2016, p. 1). Special management 
may be necessary to maintain instream flows in the river.

Unit 5: Rio Grande--Laredo

    Subunit 5a: Eagle Pass Reach: This subunit consists of 223.2 km 
(138.7 mi) of the U.S. side of the Rio Grande from Del Rio, Texas, to 
upstream of the Laredo population of Texas hornshell in Kinney and 
Maverick Counties, Texas. This subunit is primarily privately owned, 
with small portions owned by the City of Eagle Pass and the Kickapoo 
Tribe of Texas. We conclude that this reach was occupied at the time of 
listing. This conclusion is based on the collection of two live 
individuals near Del Rio between 2008 and 2011 (Karatayev et al. 2015, 
p. 8). The immobility of Texas hornshell and the continued presence of 
suitable habitat indicates the species remained in the area at the time 
of listing. This reach includes all of the PBFs necessary to support 
the continued existence of the species. Additionally, the hydrological 
connection with Subunit 5b, which contains the largest known population 
of Texas hornshell, allows for host fish movement between the subunits.
    However, due to the lack of recent records, we are analyzing this 
subunit against the second prong of the definition of critical habitat 
for unoccupied habitat out of an abundance of caution. If Subunit 5a is 
not occupied, it would provide for needed growth and expansion of the 
species in this portion of its historical range. The longer the 
occupied reach, the more likely it is that the Texas hornshell 
population can withstand stochastic events such as extreme flooding, 
dewatering, or water contamination. Therefore, Subunit 5a is essential 
for the conservation of the species.
    The Rio Grande in this subunit is heavily influenced by development 
along the Texas-Mexico border, and the river has a high sediment load 
in this reach (Texas Clean Rivers Program 2013, p. 9). Flows are 
regulated by releases from Amistad Reservoir based on hydropower 
generation and water deliveries for downstream irrigation needs (Texas 
Water Development Board 2016, p. 1). Special management may be 
necessary to improve water quality and reduce sedimentation.
    Subunit 5b: Laredo Reach: This subunit consists of 84.0 km (52.2 
mi) of the U.S. side of the Rio Grande upstream of Laredo in Webb 
County, Texas, in private and city ownership. This subunit is occupied 
and contains the largest known Texas hornshell population (Randklev et 
al. 2015, p. 7). Like subunit 5a, this subunit is heavily influenced by 
development along the Texas-Mexico border, and rapid human population 
growth as well as industrialization on the Mexican side of the river 
has stressed the existing wastewater treatment facilities, and Rio 
Grande water quality is impaired as a result (Texas Clean Rivers 
Program 2013, p. 7). All of the PBFs essential to the conservation of 
Texas hornshell are found in this reach, although special management to 
improve water quality may be necessary.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species. In 
addition, section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any agency action that 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 
proposed critical habitat.
    We published a final regulation with a revised definition of 
destruction or adverse modification on August 27, 2019 (84 FR 44976). 
Destruction or adverse modification means a direct or indirect 
alteration that appreciably diminishes the value of critical habitat as 
a whole for the conservation of a listed species.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are actions on State, tribal, local, or 
private lands that require a Federal permit (such as a permit from the 
U.S. Army Corps of Engineers under section 404 of the Clean Water Act 
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10 
of the Act) or that involve some other Federal action (such as funding 
from the Federal Highway Administration, Federal Aviation 
Administration, or the Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat, and actions 
on State, tribal, local, or private lands that are not federally 
funded, authorized, or carried out by a Federal agency, do not require 
section 7 consultation.
    As a result of section 7 consultation, we document compliance with 
the requirements of section 7(a)(2) through our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect and 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species and/or 
destroy or adversely modify critical habitat, we provide reasonable and 
prudent alternatives to the project, if any are identifiable, that 
would avoid the likelihood of jeopardy and/or destruction or adverse 
modification of critical habitat. We define ``reasonable and prudent 
alternatives'' (at 50 CFR

[[Page 30896]]

402.02) as alternative actions identified during consultation that:
    (1) Can be implemented in a manner consistent with the intended 
purpose of the action,
    (2) Can be implemented consistent with the scope of the Federal 
agency's legal authority and jurisdiction,
    (3) Are economically and technologically feasible, and
    (4) Would, in the Director's opinion, avoid the likelihood of 
jeopardizing the continued existence of the listed species and/or avoid 
the likelihood of destroying or adversely modifying critical habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
formal consultation on previously reviewed actions. These requirements 
apply when the Federal agency has retained discretionary involvement or 
control over the action (or the agency's discretionary involvement or 
control is authorized by law) and, subsequent to the previous 
consultation, we have listed a new species or designated critical 
habitat that may be affected by the Federal action, or the action has 
been modified in a manner that affects the species or critical habitat 
in a way not considered in the previous consultation. In such 
situations, Federal agencies sometimes may need to request reinitiation 
of consultation with us, but the regulations also specify some 
exceptions to the requirement to reinitiate consultation on specific 
land management plans after subsequently listing a new species or 
designating new critical habitat. See the regulations for a description 
of those exceptions.

Application of the ``Adverse Modification'' Standard

    The key factor related to the destruction or adverse modification 
determination is whether implementation of the proposed Federal action 
directly or indirectly alters the designated critical habitat in a way 
that appreciably diminishes the value of the critical habitat as a 
whole for the conservation of the listed species. As discussed above, 
the role of critical habitat is to support physical or biological 
features essential to the conservation of a listed species and provide 
for the conservation of the species. Section 4(b)(8) of the Act 
requires us to briefly evaluate and describe, in any proposed or final 
regulation that designates critical habitat, activities involving a 
Federal action that may violate 7(a)(2) of the Act by destroying or 
adversely modifying such designation.
    Activities that the Services may, during a consultation under 
section 7(a)(2) of the Act, find are likely to destroy or adversely 
modify critical habitat include, but are not limited to:
    (1) Actions that would alter the existing flow regime. Such 
activities could include, but are not limited to, impoundment, water 
diversion, and water withdrawal. These activities could eliminate or 
reduce the habitat necessary for the growth and reproduction of these 
mussels.
    (2) Actions that would significantly alter water chemistry or 
temperature. Such activities could include, but are not limited to, 
release of chemicals, biological pollutants, or heated effluents into 
the surface water or connected groundwater at a point source or by 
dispersed release (non-point source). These activities could alter 
water conditions to levels that are beyond the tolerances of the 
mussels or their fish host and result in direct or cumulative adverse 
effects to these individuals and their life cycles.
    (3) Actions that would significantly increase sediment deposition 
within the stream channel. Such activities could include, but are not 
limited to, excessive sedimentation from livestock grazing, road 
construction, channel alteration, and other watershed and floodplain 
disturbances. These activities could eliminate or reduce the habitat 
necessary for the growth and reproduction of these mussels and their 
fish host by increasing the sediment deposition to levels that would 
adversely affect their ability to complete their life cycles.

Exemptions

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

    Section 4(a)(3)(B)(i) of the Act (16 U.S.C. 1533(a)(3)(B)(i)) 
provides that: ``The Secretary shall not designate as critical habitat 
any lands or other geographic areas owned or controlled by the 
Department of Defense, or designated for its use, that are subject to 
an integrated natural resources management plan (INRMP) prepared under 
section 101 of the Sikes Act (16 U.S.C. 670a), if the Secretary 
determines in writing that such plan provides a benefit to the species 
for which critical habitat is proposed for designation.'' There are no 
Department of Defense lands within the proposed critical habitat 
designation.

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

    Section 4(b)(2) of the Act states that the Secretary shall 
designate and make revisions to critical habitat on the basis of the 
best available scientific data after taking into consideration the 
economic impact, national security impact, and any other relevant 
impact of specifying any particular area as critical habitat. The 
Secretary may exclude an area from critical habitat if he determines 
that the benefits of such exclusion outweigh the benefits of specifying 
such area as part of the critical habitat, unless he determines, based 
on the best scientific data available, that the failure to designate 
such area as critical habitat will result in the extinction of the 
species. In making that determination, the statute on its face, as well 
as the legislative history, are clear that the Secretary has broad 
discretion regarding which factor(s) to use and how much weight to give 
to any factor.
    When identifying the benefits of inclusion for an area, we consider 
the additional regulatory benefits that area would receive due to the 
protection from destruction of adverse modification as a result of 
actions with a Federal nexus; the educational benefits of mapping 
essential habitat for recovery of the listed species; and any benefits 
that may result from a designation due to State or Federal laws that 
may apply to critical habitat. In the case of the Texas hornshell, the 
benefits of critical habitat include public awareness of the presence 
of the Texas hornshell and the importance of habitat protection, and, 
where a Federal nexus exists, increased habitat protection for the 
Texas hornshell due to protection from destruction or adverse 
modification of critical habitat.
    When considering the benefits of exclusion, we consider, among 
other things, whether exclusion of a specific area is likely to result 
in conservation or the continuation, strengthening, or encouragement of 
partnerships. Continued implementation of an ongoing management plan 
that provides equal to or more conservation than a critical habitat 
designation would reduce the benefits of including that specific area 
in the critical habitat designation.
    We evaluate the existence of a conservation plan when considering 
the benefits of inclusion. We consider a variety of factors, including 
but not limited to, whether the plan is finalized; how it provides for 
the conservation of the essential physical or biological features; 
whether there is a reasonable expectation that the conservation

[[Page 30897]]

management strategies and actions contained in a management plan will 
be implemented into the future; whether the conservation strategies in 
the plan are likely to be effective; and whether the plan contains a 
monitoring program or adaptive management to ensure that the 
conservation measures are effective and can be adapted in the future in 
response to new information.
    After identifying the benefits of inclusion and the benefits of 
exclusion, we carefully weigh the two sides to evaluate whether the 
benefits of exclusion outweigh those of inclusion. If our analysis 
indicates that the benefits of exclusion outweigh the benefits of 
inclusion, we then determine whether exclusion would result in 
extinction of the species. If exclusion of an area from critical 
habitat will result in extinction, we will not exclude it from the 
designation.
    The final decision on whether to exclude any areas will be based on 
the best scientific data available at the time of the final 
designation, including information obtained during the comment period 
and information about the economic impact of designation. Accordingly, 
we have prepared a draft economic analysis concerning the proposed 
critical habitat designation, which is available for review and comment 
(see ADDRESSES).

Consideration of Economic Impacts

    Section 4(b)(2) of the Act and its implementing regulations require 
that we consider the economic impact that may result from a designation 
of critical habitat. To assess the probable economic impacts of a 
designation, we must first evaluate specific land uses or activities 
and projects that may occur in the area of the critical habitat. We 
then must evaluate the impacts that a specific critical habitat 
designation may have on restricting or modifying specific land uses or 
activities for the benefit of the species and its habitat within the 
areas proposed. We then identify which conservation efforts may be the 
result of the species being listed under the Act versus those 
attributed solely to the designation of critical habitat for this 
particular species.
    The probable economic impact of a proposed critical habitat 
designation is analyzed by comparing scenarios both ``with critical 
habitat'' and ``without critical habitat.'' The ``without critical 
habitat'' scenario represents the baseline for the analysis, which 
includes the existing regulatory and socio-economic burden imposed on 
landowners, managers, or other resource users potentially affected by 
the designation of critical habitat (e.g., under the Federal listing as 
well as other Federal, State, and local regulations). The baseline, 
therefore, represents the costs of all efforts attributable to the 
listing of the species under the Act (i.e., conservation of the species 
and its habitat incurred regardless of whether critical habitat is 
designated). The ``with critical habitat'' scenario describes the 
incremental impacts associated specifically with the designation of 
critical habitat for the species. The incremental conservation efforts 
and associated impacts would not be expected without the designation of 
critical habitat for the species. In other words, the incremental costs 
are those attributable solely to the designation of critical habitat, 
above and beyond the baseline costs. These are the costs we use when 
evaluating the benefits of inclusion and exclusion of particular areas 
from the final designation of critical habitat should we choose to 
conduct a discretionary section 4(b)(2) exclusion analysis.
    For this particular designation, we developed an Incremental 
Effects Memorandum (IEM) considering the probable incremental economic 
impacts that may result from this proposed designation of critical 
habitat. The information contained in our IEM was then used to develop 
a screening analysis of the probable effects of the designation of 
critical habitat for the Texas hornshell (Industrial Economics, Inc. 
2019).
    We began by conducting a screening analysis of the proposed 
designation of critical habitat in order to focus our analysis on the 
key factors that are likely to result in incremental economic impacts. 
The purpose of the screening analysis is to filter out the geographic 
areas in which the critical habitat designation is unlikely to result 
in probable incremental economic impacts. In particular, the screening 
analysis considers baseline costs (i.e., absent critical habitat 
designation) and includes probable economic impacts where land and 
water use may be subject to conservation plans, land management plans, 
best management practices, or regulations that protect the habitat area 
as a result of the Federal listing status of the species. The screening 
analysis filters out particular areas of critical habitat that are 
already subject to such protections and are, therefore, unlikely to 
incur incremental economic impacts. Ultimately, the screening analysis 
allows us to focus our analysis on evaluating the specific areas or 
sectors that may incur probable incremental economic impacts as a 
result of the designation. The screening analysis also assesses whether 
units that are unoccupied by the species may require additional 
management or conservation efforts as a result of the critical habitat 
designation, thereby possibly incurring incremental economic impacts. 
This screening analysis combined with the information contained in our 
IEM are what we consider our draft economic analysis of the proposed 
critical habitat designation for the Texas hornshell, and this analysis 
is summarized in the narrative below.
    Executive Orders 12866 and 13563 direct Federal agencies to assess 
the costs and benefits of available regulatory alternatives in 
quantitative (to the extent feasible) and qualitative terms. Consistent 
with the E.O. regulatory analysis requirements, our effects analysis 
under the Act may take into consideration impacts to both directly and 
indirectly affected entities, where practicable and reasonable. If 
sufficient data are available, we assess to the extent practicable the 
probable impacts to both directly and indirectly affected entities. As 
part of our screening analysis, we considered the types of economic 
activities that are likely to occur within the areas likely affected by 
the critical habitat designation.
    In our evaluation of the probable incremental economic impacts that 
may result from the proposed designation of critical habitat for the 
Texas hornshell, first we identified, in the IEM dated December 5, 
2016, probable incremental economic impacts associated with the 
following categories of activities: (1) Federal lands management 
(National Park Service, Bureau of Land Management); (2) roadway and 
bridge construction; (3) agriculture; (4) grazing; (5) groundwater 
pumping; (6) in-stream dams and diversions; (7) oil and gas production; 
and (8) border protection. We considered each industry or category 
individually. Additionally, we considered whether their activities have 
any Federal involvement. Critical habitat designation generally will 
not affect activities that do not have any Federal involvement; under 
the ESA, designation of critical habitat affects only activities 
conducted, funded, permitted, or authorized by Federal agencies. In 
areas where the Texas hornshell is present, Federal agencies already 
are required to consult with the Service under section 7 of the Act on 
activities they fund, permit, or implement that may affect the species. 
If we finalize this proposed critical habitat designation, 
consultations to avoid the destruction or adverse modification of 
critical habitat would be incorporated into the existing consultation 
process.

[[Page 30898]]

    In our IEM, we attempted to clarify the distinction between the 
effects that will result from the species being listed and those 
attributable to the critical habitat designation (i.e., difference 
between the jeopardy and adverse modification standards) for the Texas 
hornshell's critical habitat. The Texas hornshell has not been listed 
long enough for us to have conducted any section 7 consultations. It 
has been our experience that, for such species, it is more difficult to 
discern which conservation efforts are attributable to the species 
being listed and which will result solely from the designation of 
critical habitat. However, the following specific circumstances in this 
case help to inform our evaluation: (1) The essential physical or 
biological features identified for critical habitat are the same 
features essential for the life requisites of the species and (2) any 
actions that would result in sufficient harm or harassment to 
constitute jeopardy to the Texas hornshell would also likely adversely 
affect the essential physical or biological features of critical 
habitat. The IEM outlines our rationale concerning this limited 
distinction between baseline conservation efforts and incremental 
impacts of the designation of critical habitat for this species. This 
evaluation of the incremental effects has been used as the basis to 
evaluate the probable incremental economic impacts of this proposed 
designation of critical habitat.
    The proposed critical habitat designation for the Texas hornshell 
totals 463.6 mi (745.9 km) in five units, all of which were occupied at 
the time of listing. However, two subunits--4b and 5a (comprising 40 
percent of the proposed critical habitat designation)--have few records 
of Texas hornshell and are so remote that we do not believe listing the 
species made the public aware of its presence in these areas. As a 
result, we do not expect section 7 consultations to be initiated in 
these areas until additional awareness is brought to these areas when 
they are designated as critical habitat. Therefore, while all units of 
the proposed critical habitat were occupied at the time of listing, we 
conducted an economic analysis that modeled Subunits 4b and 5a as 
unoccupied so that we could more accurately represent the anticipated 
increase in public awareness and cost of project modifications when 
these areas are designated as critical habitat. As a result, our 
economic effects analysis demonstrates the maximum economic effects of 
the critical habitat designation.
    All other subunits (besides the two modeled as unoccupied) comprise 
60 percent of the designation and were modeled as occupied in the 
economic analysis. In these areas, any actions that may affect the 
species or its habitat would also affect designated critical habitat 
and it is unlikely that any additional conservation efforts would be 
recommended to address the adverse modification standard over and above 
those recommended as necessary to avoid jeopardizing the continued 
existence of the Texas hornshell. Therefore, only administrative costs 
are expected in approximately 60 percent of the proposed critical 
habitat designation. While this additional analysis will require time 
and resources by both the Federal action agency and the Service, we 
believe that in most circumstances these costs would predominantly be 
administrative in nature and would not exceed $89,000 in a single year.
    The remaining subunits (185.2 mi (298.0) km, or 40 percent of the 
total proposed critical habitat designation) that were analyzed as 
unoccupied by the species for the purposes of the economic analysis are 
essential for the conservation of the species. In these areas, any 
conservation efforts or associated probable impacts would be considered 
incremental effects attributed to the critical habitat designation. 
Subunit 4b (Rio Grande-Lower Canyons, Langtry Reach) is very remote 
with little to no development, and activities that could affect the 
Texas hornshell or its habitat are not expected to occur in these 
areas. We do not anticipate any projects because of how remote Subunit 
4b is, as well as the lack of historical, current, or planned 
activities in this area. Subunit 5a (Rio Grande-Laredo, Eagle Pass 
Reach) has potential for projects to occur; however, because this reach 
is upstream of occupied habitat, for large projects, project 
modifications requested to avoid adverse modification are likely to be 
the same as those that would be needed to avoid jeopardizing the 
species in downstream, occupied critical habitat. For small projects 
that may affect critical habitat in this reach, project modifications 
would be the same as conservation measures currently included in best 
management practices under Clean Water Act section 404 permits issued 
by the U.S. Army Corps of Engineers. Therefore, costs are unlikely to 
exceed $100 million in any single year and would not be significant, 
based on the definition of significance in E.O. 12866.
    The entities most likely to incur incremental costs are parties to 
section 7 consultations, including Federal action agencies and, in some 
cases, third parties, most frequently State agencies or municipalities. 
Activities we expect will be subject to consultations that may involve 
private entities as third parties are residential and commercial 
development that may occur on private lands. However, based on 
coordination efforts with State and local agencies, the cost to private 
entities within these sectors is expected to be relatively minor 
(administrative costs of less than $10,000 per consultation effort) and 
would not be significant (exceed $100 million in a single year).
    The probable incremental economic impacts of the Texas hornshell 
critical habitat designation are expected to be limited to additional 
administrative effort as well as minor costs of conservation efforts 
resulting from a small number of future section 7 consultations. This 
is due to two factors: (1) In proposed critical habitat stream reaches 
that were analyzed as occupied by the species (60 percent), incremental 
economic impacts of critical habitat designation, other than 
administrative costs, are unlikely; and (2) in proposed areas that were 
analyzed as if they were unoccupied by the Texas hornshell (40 
percent), few actions are anticipated that will result in section 7 
consultation or associated project modifications. At approximately 
$10,000 or less per consultation, in order to reach the threshold of 
$100 million of incremental administrative impacts in a single year, 
critical habitat designation would have to result in more than 11,000 
consultations in a single year. Thus, the annual administrative burden 
is unlikely to reach $100 million.
    As we stated earlier, we are soliciting data and comments from the 
public on the draft economic analysis, as well as all aspects of the 
proposed rule and our amended required determinations. We may revise 
the proposed rule or supporting documents to incorporate or address 
information we receive during the public comment period. In particular, 
we may exclude an area from critical habitat if we determine that the 
benefits of excluding the area outweigh the benefits of including the 
area, provided the exclusion will not result in the extinction of this 
species.

Exclusions

    Based on the information provided by entities seeking exclusion, as 
well as any additional public comments received, we will evaluate 
whether certain lands are appropriate for exclusion from the final 
designation under section 4(b)(2) of the Act. If the analysis indicates 
that the benefits of excluding lands from the final designation 
outweigh the benefits of designating those lands as critical

[[Page 30899]]

habitat, then the Secretary may exercise his discretion to exclude the 
lands from the final designation.
    We are considering whether to exclude Unit 1: Pecos Tributary Unit 
under section 4(b)(2) of the Act from the final critical habitat 
designation for the Texas hornshell because of the conservation 
agreements discussed earlier in this document. The Service has 
collaborated with water users, oil and gas developers, landowners, and 
other partners to implement a CCA and CCAA for the Texas hornshell on 
State, Federal, and private lands in the Black and Delaware River 
watersheds. The key conservation measures in the agreements are 
designed to limit oil and gas development to areas outside of the Black 
and Delaware River floodplains, minimize erosion in order to maintain 
suitable substrate, and maintain minimum water flows in the rivers. 
Along with these measures, the partners to the agreement are evaluating 
alternatives to the multiple low water crossings on the Black River to 
reduce the potential for river contamination. Partners are considering 
alternate crossing locations that could include bridges designed to 
allow host fishes to pass through in addition to decreasing the risk of 
contamination events.
    The Pecos Tributary Unit consists of two subunits, the Black River 
Subunit (9.7 mi (15.6 km)) and the Delaware River Subunit (31.1 mi 
(50.0 km)). A CCA and CCAA between the Service, BLM, New Mexico State 
Land Office, and Center of Excellence has been completed for the Black 
and Delaware Rivers in New Mexico and Texas. We are considering the 
exclusion of non-Federal lands covered by this plan that provide for 
the conservation of the Texas hornshell. We are requesting comments on 
the benefit to the Texas hornshell from the CCA/CCAA; however, at this 
time, we are not proposing to exclude any area within the proposed 
critical habitat for the Texas hornshell.
    However, we specifically solicit comments on the inclusion or 
exclusion of the Pecos Tributary Unit.
    Any other plans in development that are submitted to us will be 
evaluated and could result in the exclusion of additional proposed 
critical habitat units from the final designation.

Exclusions Based on Economic Impacts

    Under section 4(b)(2) of the Act, we consider the economic impacts 
of specifying any particular area as critical habitat. In order to 
consider economic impacts, we prepared an analysis of the economic 
impacts of the proposed critical habitat designation and related 
factors. Potential land use sectors that may be affected by the Texas 
hornshell critical habitat designation include water diversion, 
impoundment repairs, bridge and highway maintenance, oil and gas 
development, border protection, grazing, groundwater withdrawals, and 
agriculture.
    During the development of a final designation, we will consider any 
additional economic impact information received through the public 
comment period, and as such areas may be excluded from the final 
critical habitat designation under section 4(b)(2) of the Act and our 
implementing regulations at 50 CFR 424.19.

Impacts on National Security and Homeland Security

    Section 4(a)(3)(B)(i) of the Act may not cover all Department of 
Defense (DoD) lands or areas that pose potential national-security 
concerns (e.g., a DoD installation that is in the process of revising 
its INRMP for a newly listed species or a species previously not 
covered). If a particular area is not covered under section 
4(a)(3)(B)(i), national-security or homeland-security concerns are not 
a factor in the process of determining what areas meet the definition 
of ``critical habitat.'' Nevertheless, when designating critical 
habitat under section 4(b)(2), the Service must consider impacts on 
national security, including homeland security, on lands or areas not 
covered by section 4(a)(3)(B)(i). Accordingly, we will always consider 
for exclusion from the designation areas for which DoD, Department of 
Homeland Security (DHS), or another Federal agency has requested 
exclusion based on an assertion of national-security or homeland-
security concerns.
    We cannot, however, automatically exclude requested areas. When 
DoD, DHS, or another Federal agency requests exclusion from critical 
habitat on the basis of national-security or homeland-security impacts, 
it must provide a reasonably specific justification of an incremental 
impact on national security that would result from the designation of 
that specific area as critical habitat. That justification could 
include demonstration of probable impacts, such as impacts to ongoing 
border-security patrols and surveillance activities, or a delay in 
training or facility construction, as a result of compliance with 
section 7(a)(2) of the Act. If the agency requesting the exclusion does 
not provide us with a reasonably specific justification, we will 
contact the agency to recommend that it provide a specific 
justification or clarification of its concerns relative to the probable 
incremental impact that could result from the designation. If the 
agency provides a reasonably specific justification, we will defer to 
the expert judgment of DoD, DHS, or another Federal agency as to: (1) 
Whether activities on its lands or waters, or its activities on other 
lands or waters, have national-security or homeland-security 
implications; (2) the importance of those implications; and (3) the 
degree to which the cited implications would be adversely affected in 
the absence of an exclusion. In that circumstance, in conducting a 
discretionary section 4(b)(2) exclusion analysis, we will give great 
weight to national-security and homeland-security concerns in analyzing 
the benefits of exclusion.
    We are not considering or proposing any lands for exclusions based 
on national security impacts under section 4(b)(2) of the Act in this 
proposed critical habitat rule. We have coordinated with the DHS and 
will continue to do so during the development of the final rule. U.S. 
Customs and Border Protection indicated that construction and 
maintenance of boat ramps, sediment removal, and dam construction may 
be affected by the designation of critical habitat for the Texas 
hornshell. We note that Congress has provided to the Secretary of 
Homeland Security a number of authorities necessary to carry out the 
Department's border security mission. One of those authorities is found 
at section 102 of the Illegal Immigration Reform and Immigrant 
Responsibility Act of 1996, as amended (``IIRIRA''). In section 102(a) 
of IIRIRA, Congress provided that the Secretary of Homeland Security 
shall take such actions as may be necessary to install additional 
physical barriers and roads (including the removal of obstacles to 
detection of illegal entrants) in the vicinity of the United States 
border to deter illegal crossings in areas of high illegal entry into 
the United States. In section 102(b) of IIRIRA, Congress mandated the 
installation of additional fencing, barriers, roads, lighting, cameras, 
and sensors on the southwest border. Finally, in section 102(c) of 
IIRIRA, Congress granted to the Secretary of Homeland Security the 
authority to waive all legal requirements that he determines are 
necessary to ensure the expeditious construction of barriers and roads 
authorized by section 102 of IIRIRA. On February 20, 2020, the 
Secretary of Homeland Security issued waivers for legal requirements 
covering border barrier activities directly in the vicinity of the 
Texas hornshell's known range (85 FR 9794).

[[Page 30900]]

Exclusions Based on Other Relevant Impacts

    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts on national 
security. We consider a number of factors including whether there are 
permitted conservation plans covering the species in the area such as 
habitat conservation plans, safe harbor agreements, or CCAAs, or 
whether there are non-permitted conservation agreements and 
partnerships that would be encouraged by designation of, or exclusion 
from, critical habitat. In addition, we look at the existence of tribal 
conservation plans and partnerships and consider the government-to-
government relationship of the United States with tribal entities. We 
have been in contact with the Kickapoo Traditional Tribe of Texas 
during the development of this proposed rule and will continue to do so 
during the development of final critical habitat. We also consider any 
social impacts that might occur because of the designation.

Public Hearings

    We have scheduled a public informational meeting and public hearing 
on this proposed rule to designate critical habitat for the Texas 
hornshell. We will hold the public informational meeting and public 
hearing on the date and at the times listed above under Public 
informational meeting and public hearing in DATES. We are holding the 
public informational meeting and public hearing via the Zoom online 
video platform and via teleconference so that participants can attend 
remotely. For security purposes, registration is required. To listen 
and view the meeting and hearing via Zoom, listen to the meeting and 
hearing by telephone, or provide oral public comments at the public 
hearing by Zoom or telephone, you must register. For information on how 
to register, or if you encounter problems joining Zoom the day of the 
meeting, visit https://www.fws.gov/southwest/. Registrants will receive 
the Zoom link and the telephone number for the public informational 
meeting and public hearing. If applicable, interested members of the 
public not familiar with the Zoom platform should view the Zoom video 
tutorials (https://support.zoom.us/hc/en-us/articles/206618765-Zoom-video-tutorials) prior to the public informational meeting and public 
hearing.
    The public hearing will provide interested parties an opportunity 
to present verbal testimony (formal, oral comments) regarding this 
proposed rule. While the public informational meeting will be an 
opportunity for dialogue with the Service, the public hearing is not: 
It is a forum for accepting formal verbal testimony. In the event there 
is a large attendance, the time allotted for oral statements may be 
limited. Therefore, anyone wishing to make an oral statement at the 
public hearing for the record is encouraged to provide a prepared 
written copy of their statement to us through the Federal eRulemaking 
Portal, or U.S. mail (see ADDRESSES, above). There are no limits on the 
length of written comments submitted to us. Anyone wishing to make an 
oral statement at the public hearing must register before the hearing 
(https://www.fws.gov/southwest/). The use of a virtual public hearing 
is consistent with our regulations at 50 CFR 424.16(c)(3).

Required Determinations

Regulatory Planning and Review (Executive Orders 12866 and 13563)

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

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

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

[[Page 30901]]

only Federal action agencies will be directly regulated by this 
designation. There is no requirement under the RFA to evaluate the 
potential impacts to entities not directly regulated. Moreover, Federal 
agencies are not small entities. Therefore, because no small entities 
are directly regulated by this rulemaking, the Service certifies that, 
if promulgated, the proposed critical habitat designation will not have 
a significant economic impact on a substantial number of small 
entities.
    In summary, we have considered whether the proposed designation 
would result in a significant economic impact on a substantial number 
of small entities. For the above reasons and based on currently 
available information, we certify that, if promulgated, the proposed 
critical habitat designation would not have a significant economic 
impact on a substantial number of small business entities. Therefore, 
an initial regulatory flexibility analysis is not required.

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

    Executive Order 13211 (Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use) requires 
agencies to prepare Statements of Energy Effects when undertaking 
certain actions. Oil and gas leases occur within the watershed of both 
subunits in Unit 1: Pecos Tributary Unit. We do not expect designation 
of critical habitat for the Texas hornshell to significantly affect the 
production under these leases because we anticipate most companies will 
participate in the voluntary conservation measures provided in the 
CCAA. Further, in our economic analysis, we did not find that the 
designation of this proposed critical habitat will significantly affect 
energy supplies, distribution, or use. Therefore, this action is not a 
significant energy action, and no Statement of Energy Effects is 
required.

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

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make the following findings:
    (1) This rule will not produce a Federal mandate. In general, a 
Federal mandate is a provision in legislation, statute, or regulation 
that would impose an enforceable duty upon State, local, or tribal 
governments, or the private sector, and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; Aid to Families 
with Dependent Children work programs; Child Nutrition; Food Stamps; 
Social Services Block Grants; Vocational Rehabilitation State Grants; 
Foster Care, Adoption Assistance, and Independent Living; Family 
Support Welfare Services; and Child Support Enforcement. ``Federal 
private sector mandate'' includes a regulation that ``would impose an 
enforceable duty upon the private sector, except (i) a condition of 
Federal assistance or (ii) a duty arising from participation in a 
voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities that receive 
Federal funding, assistance, or permits, or that otherwise require 
approval or authorization from a Federal agency for an action, may be 
indirectly impacted by the designation of critical habitat, the legally 
binding duty to avoid destruction or adverse modification of critical 
habitat rests squarely on the Federal agency. Furthermore, to the 
extent that non-Federal entities are indirectly impacted because they 
receive Federal assistance or participate in a voluntary Federal aid 
program, the Unfunded Mandates Reform Act would not apply, nor would 
critical habitat shift the costs of the large entitlement programs 
listed above onto State governments.
    (2) We do not believe that this rule will significantly or uniquely 
affect small governments because small governments will be affected 
only to the extent that any programs having Federal funds, permits, or 
other authorized activities must ensure that their actions will not 
adversely affect the critical habitat. Therefore, a Small Government 
Agency Plan is not required.

Takings--Executive Order 12630

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

Federalism--Executive Order 13132

    In accordance with E.O. 13132 (Federalism), this proposed rule does 
not have significant Federalism effects. A Federalism assessment is not 
required. In keeping with Department of the Interior and Department of 
Commerce policy, we request information from, and coordinated 
development of this proposed critical habitat designation with, 
appropriate State resource agencies in New Mexico and Texas. From a 
federalism perspective, the designation of critical habitat directly 
affects only the responsibilities of Federal agencies. The Act imposes 
no other duties with respect to critical habitat, either for States and 
local governments, or for anyone else. As a result, the rule does not 
have substantial direct effects either on the States, or on the 
relationship between the national government and the States, or on the 
distribution of powers and responsibilities among the various levels of 
government. The designation may have some benefit to these governments 
because the areas

[[Page 30902]]

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

Civil Justice Reform--Executive Order 12988

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

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

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act of 1995 (44 
U.S.C. 3501 et seq.). This rule will not impose recordkeeping or 
reporting requirements on State or local governments, individuals, 
businesses, or organizations. An agency may not conduct or sponsor, and 
a person is not required to respond to, a collection of information 
unless it displays a currently valid OMB control number.

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

    It is our position that, outside the jurisdiction of the U.S. Court 
of Appeals for the Tenth Circuit, we do not need to prepare 
environmental analyses pursuant to the National Environmental Policy 
Act (NEPA; 42 U.S.C. 4321 et seq.) in connection with designating 
critical habitat under the Act. We published a notice outlining our 
reasons for this determination in the Federal Register on October 25, 
1983 (48 FR 49244). This position was upheld by the U.S. Court of 
Appeals for the Ninth Circuit (Douglas County v. Babbitt, 48 F.3d 1495 
(9th Cir. 1995), cert. denied 516 U.S. 1042 (1996)).] However, when the 
range of the species includes States within the Tenth Circuit, such as 
that of the Texas hornshell, under the Tenth Circuit ruling in Catron 
County Board of Commissioners v. U.S. Fish and Wildlife Service, 75 
F.3d 1429 (10th Cir. 1996), we undertake a NEPA analysis for critical 
habitat designation. We invite the public to comment on the extent to 
which this proposed regulation may have a significant impact on the 
human environment, or fall within one of the categorical exclusions for 
actions that have no individual or cumulative effect on the quality of 
the human environment. We will complete our analysis, in compliance 
with NEPA, before finalizing this proposed rule.

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), Executive Order 13175 (Consultation and 
Coordination With Indian Tribal Governments), and the Department of the 
Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. In accordance with 
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, 
Federal-Tribal Trust Responsibilities, and the Endangered Species Act), 
we readily acknowledge our responsibilities to work directly with 
tribes in developing programs for healthy ecosystems, to acknowledge 
that tribal lands are not subject to the same controls as Federal 
public lands, to remain sensitive to Indian culture, and to make 
information available to tribes.
    There are tribal lands in Texas included in this proposed 
designation of critical habitat. The Kickapoo Indian Reservation of 
Texas owns 1.3 km (0.8 mi) adjacent to the Rio Grande in the Rio 
Grande-Eagle Pass Reach subunit. Using the criteria found in the 
Criteria Used To Identify Critical Habitat section, we have determined 
that all of the areas proposed for designation on tribal lands are 
essential to the conservation of the species. We will seek government-
to-government consultation with these tribes throughout the proposal 
and development of the final designation of Texas hornshell critical 
habitat.

Clarity of the Rule

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

References Cited

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

Authors

    The primary authors of this proposed rulemaking are the staff 
members of the Texas Coastal Ecological Services Field Office.

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

[[Page 30903]]

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

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

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

0
2. Amend Sec.  17.11(h), the List of Endangered and Threatened 
Wildlife, by revising the entry for ``Hornshell, Texas'' under CLAMS to 
read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                              Listing citations
           Common name                Scientific name        Where listed         Status        and applicable
                                                                                                    rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
              Clams
 
                                                  * * * * * * *
    Hornshell, Texas.............  Popenaias popeii....  Wherever found......            E   83 FR 5720, 2/9/
                                                                                              2018; 50 CFR
                                                                                              17.95(f).\CH\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

* * * * *
0
3. In Sec.  17.95, amend paragraph (f) by adding an entry for ``Texas 
Hornshell Popenaias popeii),'' after the entry for ``Carolina 
Heelsplitter (Lasmigona decorata)'', to read as follows:


Sec.  17.95   Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and snails.
* * * * *
Texas Hornshell (Popenaias popeii)
    (1) Critical habitat units are depicted for Eddy County, New 
Mexico, and in Brewster, Culberson, Kinney, Maverick, Terrell, Val 
Verde, and Webb Counties, Texas, on the maps in this entry.
    (2) Within these areas, the physical or biological features 
essential to the conservation of the Texas hornshell consist of a 
riverine system that includes:
    (i) Flowing water at rates high enough to support clean-swept 
substrate but not so high as to dislodge individuals;
    (ii) Crevices beneath boulders, shelves, and within undercut banks 
with seams of fine sediment;
    (iii) River carpsucker (Carpiodes carpio), red shiner (Cyprinella 
lutrensis), and gray redhorse (Moxostoma congestum) present; and
    (iv) Water quality parameters within the following ranges:
    (A) Salinity below 0.9 ppt;
    (B) Ammonia below 0.7 mg/L;
    (C) Low levels of contaminants; and
    (D) Dissolved oxygen levels within substrate >1.3mg/L.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
[EFFECTIVE DATE OF THE FINAL RULE].
    (4) Data layers defining map units were created using U.S. 
Geological Survey digital ortho-photo quarter-quadrangles, and critical 
habitat units were then mapped using Universal Transverse Mercator 
(UTM) Zone 15N coordinates. The maps in this entry, as modified by any 
accompanying regulatory text, establish the boundaries of the critical 
habitat designation. The coordinates or plot points or both on which 
each map is based are available to the public at the Service's internet 
site, https://www.fws.gov/southwest/es/TexasCoastal/, at http://www.regulations.gov in Docket No. FWS-R2-ES-2018-0021, and at the field 
office responsible for this designation. You may obtain field office 
location information by contacting one of the Service regional offices, 
the addresses of which are listed at 50 CFR 2.2.
    (5) Note: Index map follows:
BILLING CODE 4333-15-P

[[Page 30904]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.006

    (6) Unit 1: Pecos Tributary Unit, Eddy County, New Mexico, and 
Culberson County, Texas.
    (i) Unit 1 consists of two subunits: Subunit 1a (Black River 
Subunit) contains 15.6 km (9.7 mi) in Eddy County, New Mexico, and is 
composed of lands in private ownership; Subunit 1b (Delaware River 
Subunit) contains 50.0 km (31.1 mi) in Eddy County, New Mexico, and 
Culberson County, Texas, and is composed of lands in Federal (13.2 km 
(8.2 mi)) and private (36.8 km (22.9 mi)) ownership.
    (ii) Map of Unit 1, Pecos Tributary Unit, Eddy County, New Mexico, 
and Culberson County, Texas, follows:

[[Page 30905]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.007

    (7) Unit 2: Pecos River Unit, Val Verde and Terrell Counties, 
Texas.
    (i) Unit 2 consists of 137.9 km (85.7 mi) in Val Verde and Terrell 
Counties, Texas, and is composed of lands in Federal (2.7 km (1.7 mi)), 
non-governmental organization (7.6 km (4.7 mi)), and private (127.6 km 
(79.3 mi)) ownership.
    (ii) Map of Unit 2, Pecos River Unit, Val Verde and Terrell 
Counties, Texas, follows:

[[Page 30906]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.008

    (8) Unit 3: Devils River Unit, Val Verde County, Texas.
    (i) Unit 3 consists of 53.1 km (33.0 mi) in Val Verde County, 
Texas, and is composed of lands in Federal (2.6 km (1.6 mi)), State 
(1.6 km (1.0 mi)), non-governmental organization (16.7 km (10.4 mi)), 
and private (32.2 km (20.0 mi)) ownership.
    (ii) Map of Unit 3, Devils River Unit, Val Verde County, Texas, 
follows:

[[Page 30907]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.009

    (9) Unit 4: Rio Grande--Lower Canyons Unit, Terrell, Brewster, and 
Val Verde Counties, Texas.
    (i) Unit 4 consists of two subunits: Subunit 4a (Lower Canyons 
Reach Subunit) contains 107.3 km (66.7 mi) in Terrell and Brewster 
Counties, Texas, and is composed of lands in State (7.1 km (4.4 mi)), 
and Federal (100.3 km (62.3 mi)) ownership; Subunit 4b (Langtry Reach 
Subunit) contains 74.8 km (46.5 mi) in Brewster and Val Verde Counties, 
Texas, and is composed of lands in Federal (69.8 km (43.4 mi)) and 
private (5.0 km (3.1 mi)) ownership.
    (ii) Map of Unit 4, Rio Grande--Lower Canyons Unit, Terrell, 
Brewster, and Val Verde Counties, Texas, follows:

[[Page 30908]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.010

    (10) Unit 5: Rio Grande--Laredo Unit, Kinney, Maverick, and Webb 
Counties, Texas.
    (i) Unit 5 consists of two subunits: Subunit 5a (Eagle Pass Reach 
Subunit) contains 223.2 km (138.7 mi) in Kinney and Maverick Counties, 
Texas, and is composed of lands in city (0.8 km (0.5 mi)), Tribal (1.3 
km (0.8 mi), and private (221.1 km (137.4 mi)) ownership; Subunit 5b 
(Laredo Reach Subunit) contains 84.0 km (52.2 mi) in Webb County, 
Texas, and is composed of lands in city (0.5 km (0.3 mi)) and private 
(83.5 km (51.9 mi)) ownership.
    (ii) Map of Unit 5, Rio Grande-Laredo Unit, Kinney, Maverick, and 
Webb Counties, Texas, follows:

[[Page 30909]]

[GRAPHIC] [TIFF OMITTED] TP10JN21.011

* * * * *

Martha Williams,
Principal Deputy Director, Exercising the Delegated Authority of the 
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2021-11966 Filed 6-9-21; 8:45 am]
BILLING CODE 4333-15-C