Endangered and Threatened Wildlife and Plants; Endangered Status for the Eastern Regal Fritillary, and Threatened Status With Section 4(d) Rule for the Western Regal Fritillary, 63888-63909 [2024-16982]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 89, Number 151 (Tuesday, August 6, 2024)]
[Proposed Rules]
[Pages 63888-63909]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-16982]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R6-ES-2023-0182; FXES1111090FEDR-245-FF09E21000]
RIN 1018-BF92


Endangered and Threatened Wildlife and Plants; Endangered Status 
for the Eastern Regal Fritillary, and Threatened Status With Section 
4(d) Rule for the Western Regal Fritillary

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list the eastern regal fritillary (Argynnis idalia idalia) as an 
endangered species and to list the western regal fritillary (A. i. 
occidentalis) as a threatened species under the Endangered Species Act 
of 1973, as amended (Act). This determination also serves as our 12-
month finding on a petition to list the regal fritillary, as these two 
subspecies make up the entire species. After a review of the best 
available scientific and commercial information, we find that listing 
both subspecies is warranted. Accordingly, we propose to list the 
eastern subspecies as endangered and the western subspecies as 
threatened with protective regulations issued under section 4(d) of the 
Act (a ``4(d) rule''). We find that designation of critical habitat for 
both subspecies is not determinable at this time.

DATES: We will accept comments received or postmarked on or before 
October 7, 2024. Comments submitted electronically using the Federal 
eRulemaking Portal (see ADDRESSES, below) must be received by 11:59 
p.m. eastern time on the closing date. We must receive requests for a 
public hearing, in writing, at the address shown in FOR FURTHER 
INFORMATION CONTACT by September 20, 2024.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R6-ES-2023-0182, 
which is the docket number for this rulemaking. Then, click on the 
Search button. On the resulting page, in the panel on the left side of 
the screen, under the Document Type heading, check the Proposed Rule 
box to locate this document. You may submit a comment by clicking on 
``Comment.''

[[Page 63889]]

    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R6-ES-2023-0182, U.S. Fish and Wildlife Service, 
MS: PRB/3W, 5275 Leesburg Pike, Falls Church, VA 22041-3803.
    We request that you send comments only by the methods described 
above. We will post all comments on https://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see Information Requested, below, for more information).
    Availability of supporting materials: Supporting materials, such as 
the species status assessment report, are available at https://www.regulations.gov at Docket No. FWS-R6-ES-2023-0182.

FOR FURTHER INFORMATION CONTACT: 
    For the eastern regal fritillary--Sonja Jahrsdoerfer, Project 
Leader, Pennsylvania Ecological Services Field Office, 110 Radnor Road, 
Suite 101, State College, PA 16801; telephone 814-206-7474.
    For the western regal fritillary--Chris Swanson, Field Supervisor, 
North and South Dakota Ecological Services Field Offices, 420 South 
Garfield Avenue, Suite 400, Pierre, SD 57501; telephone 605-222-0228. 
Individuals in the United States who are deaf, deafblind, hard of 
hearing, or have a speech disability may dial 711 (TTY, TDD, or 
TeleBraille) to access telecommunications relay services. Individuals 
outside the United States should use the relay services offered within 
their country to make international calls to the point-of-contact in 
the United States. Please see Docket No. FWS-R6-ES-2023-0182 on https://www.regulations.gov for a document that summarizes this proposed rule.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Act (16 U.S.C. 1531 et 
seq.), the term ``species'' includes any subspecies of fish or wildlife 
or plants, and any distinct population segment of any species of 
vertebrate fish or wildlife which interbreeds when mature. A subspecies 
warrants listing under the Act if it meets the definition of an 
endangered species (in danger of extinction throughout all or a 
significant portion of its range) or a threatened species (likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range). If we determine that a 
subspecies warrants listing, we must list the subspecies promptly and 
designate the subspecies' critical habitat to the maximum extent 
prudent and determinable. We have determined that the eastern regal 
fritillary (eastern subspecies) meets the Act's definition of an 
endangered species and that the western regal fritillary (western 
subspecies) meets the Act's definition of a threatened species; 
therefore, we are proposing to list them as such. Listing a subspecies 
as an endangered or threatened species can be completed only by issuing 
a rule through the Administrative Procedure Act rulemaking process (5 
U.S.C. 551 et seq.).
    What this document does. We propose to list the eastern regal 
fritillary as an endangered species and to list the western regal 
fritillary as a threatened species with a 4(d) rule. As explained later 
in this document, we conclude that the designation of critical habitat 
for these subspecies is not determinable at this time.
    The basis for our action. Under the Act, we may determine that a 
subspecies is an endangered or threatened species because of any of 
five factors: (A) the present or threatened destruction, modification, 
or curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that the eastern regal 
fritillary is endangered due to the loss and fragmentation of its 
remaining grassland habitats from invasive plants and woody 
encroachment (Factor A) and periodic disturbances, such as fire, 
military operations, and other management activities if they are too 
large, frequent, or intense (Factor A). These threats are exacerbated 
by the ongoing effects of drought and climate change (Factors A and E).
    We have determined that the western regal fritillary is threatened 
due to the expected continued loss and fragmentation of large, intact 
native grasslands through conversion by agriculture and development 
(Factor A); invasive plants and woody vegetation (Factor A); the 
reduction of violets and nectar sources from the broadcast application 
of herbicides (Factor A); and periodic disturbances from fire, mowing, 
and haying that are too large, frequent, or intense (Factor A). These 
threats are all exacerbated by the ongoing and expected effects of 
drought and climate change (Factors A and E).
    Section 4(a)(3) of the Act requires the Secretary of the Interior 
(Secretary), to the maximum extent prudent and determinable, to 
designate critical habitat concurrent with listing. Section 3(5)(A) of 
the Act defines critical habitat as (i) the specific areas within the 
geographical area occupied by the species at the time it is listed, on 
which are found those physical or biological features (I) essential to 
the conservation of the species and (II) which may require special 
management considerations or protection; and (ii) specific areas 
outside the geographical area occupied by the species at the time it is 
listed, upon a determination by the Secretary that such areas are 
essential for the conservation of the species. Section 4(b)(2) of the 
Act states that the Secretary must make the designation on the basis of 
the best scientific data available and after taking into consideration 
the economic impact, the impact on national security, and any other 
relevant impacts of specifying any particular area as critical habitat.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from governmental agencies, Native American 
Tribes, the scientific community, industry, or any other interested 
parties concerning this proposed rule. We particularly seek comments 
concerning:
    (1) The subspecies' biology, range, and population trends, 
including:
    (a) Current ranges, including distribution patterns and the 
locations of any additional populations of the subspecies;
    (b) Current population levels, and current and projected trends; 
and
    (c) Past and ongoing conservation measures for the subspecies, 
their habitats, or both.
    (2) Threats and conservation actions affecting the subspecies, 
including:
    (a) Factors that may be affecting the continued existence of the 
subspecies, which may include habitat modification or destruction, 
overutilization, disease, predation, the inadequacy of existing 
regulatory mechanisms, or other natural or manmade factors;
    (b) Relevant data concerning any threats (or lack thereof) to the 
subspecies; and
    (c) Existing regulations or conservation actions that may be 
addressing threats to these subspecies.
    (3) Additional information concerning the current status of the 
subspecies.
    (4) Information to assist with applying or issuing protective 
regulations under section 4(d) of the Act that may be

[[Page 63890]]

necessary and advisable to provide for the conservation of the western 
regal fritillary.
    (a) In particular, information concerning the extent to which we 
should include any of the section 9 prohibitions in the 4(d) rule; or
    (b) whether we should consider any additional or different 
exceptions from the prohibitions in the 4(d) rule.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for, or 
opposition to, the action under consideration without providing 
supporting information, although noted, do not provide substantial 
information necessary to support a determination. Section 4(b)(1)(A) of 
the Act directs that determinations as to whether any species is an 
endangered or a threatened species must be made solely on the basis of 
the best scientific and commercial data available.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in ADDRESSES.
    If you submit information via https://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the website. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on https://www.regulations.gov.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov.
    Our final determinations may differ from this proposal because we 
will consider all comments we receive during the comment period as well 
as any relevant information that becomes available after this proposal 
is published. Based on the new information we receive (and, if 
relevant, any comments on that new information), we may conclude that 
the eastern subspecies is threatened instead of endangered or that the 
western subspecies is endangered instead of threatened, or we may 
conclude that one or both of the subspecies do not warrant listing as 
either an endangered species or a threatened species. In addition, we 
may change the parameters of the prohibitions or the exceptions to 
those prohibitions in the protective regulations under section 4(d) for 
the western regal fritillary if appropriate in light of comments and 
new information received. For example, we may expand the prohibitions 
to include prohibiting additional activities if we conclude that those 
additional activities are not compatible with conservation of the 
western regal fritillary. Conversely, we may establish additional 
exceptions to the prohibitions in the final rule if we conclude that 
the activities would facilitate or are compatible with the conservation 
and recovery of the western subspecies. In our final rule, we will 
clearly explain our rationale and the basis for our final decisions, 
including why we made changes, if any, that differ from this proposal.

Public Hearing

    Section 4(b)(5) of the Act provides for a public hearing on this 
proposal, if requested. Requests must be received by the date specified 
in DATES. Such requests must be sent to the address shown in FOR 
FURTHER INFORMATION CONTACT. We will schedule a public hearing on this 
proposal, if requested, and announce the date, time, and place of the 
hearing, as well as how to obtain reasonable accommodations, in the 
Federal Register and local newspapers at least 15 days before the 
hearing. We may hold the public hearing in person or virtually via 
webinar. We will announce any public hearing on our website, in 
addition to the Federal Register. The use of virtual public hearings is 
consistent with our regulations at 50 CFR 424.16(c)(3).

Previous Federal Actions

    We designated the regal fritillary as a Category 2 candidate in the 
May 22, 1984, Review of Invertebrate Wildlife for Listing as Endangered 
or Threatened Species (49 FR 21664). We defined Category 2 candidates 
as taxa for which we had information that proposed listing was possibly 
appropriate, but conclusive data on biological vulnerability and 
threats were not available to support a proposed rule at the time. The 
species remained so designated in subsequent annual candidate notices 
of review (CNORs) (54 FR 554, January 6, 1989; 56 FR 58804, November 
21, 1991; 59 FR 58982, November 15, 1994). In the February 28, 1996, 
CNOR (61 FR 7596), we discontinued the designation of Category 2 
species as candidates; therefore, the regal fritillary was no longer a 
candidate species.
    On April 19, 2013, we received a petition from WildEarth Guardians 
to list the regal fritillary under the Act. On September 18, 2015, we 
published in the Federal Register (80 FR 56423) a substantial 90-day 
finding for the regal fritillary. The eastern and western subspecies 
are the only two subspecies of the regal fritillary species, so this 
document constitutes our 12-month warranted petition finding and our 
proposed listing rule for the regal fritillary.

Peer Review

    A species status assessment (SSA) team prepared an SSA report for 
the eastern and western subspecies of regal fritillary. The SSA team 
was composed of Service biologists, in consultation with other species 
experts. The SSA report represents a compilation of the best scientific 
and commercial data available concerning the status of both subspecies, 
including the impacts of past, present, and future factors (both 
negative and beneficial) affecting the subspecies.
    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), and our August 22, 
2016, memorandum updating and clarifying the role of peer review in 
listing actions under the Act, we solicited independent scientific 
review of the information contained in the SSA report for the eastern 
and western subspecies. We sent the SSA report to 14 appropriate and 
independent peer reviewers and received 5 responses. Results of this 
structured peer review process can be found at https://www.regulations.gov under Docket No. FWS-R6-ES-2023-0182 and at https://fws.gov/library/categories/peer-review-plans. In preparing this 
proposed rule, we incorporated the results of these reviews, as 
appropriate, into the SSA report, which is the foundation for this 
proposed rule.

Summary of Peer Reviewer Comments

    As discussed in Peer Review above, we received comments from five 
peer reviewers on the draft SSA report. We reviewed all comments from 
the peer reviewers for substantive issues and new information regarding 
the contents of the SSA report. The peer reviewers concurred with our 
methods and conclusions, and provided additional information, 
clarifications, and suggestions, including corrections on wingspan 
measurements, suggestions for additional relationships between nodes on 
our conceptual models, potential uncertainty associated with geospatial 
landcover and climate

[[Page 63891]]

models, and other editorial suggestions. We updated the SSA report 
accordingly. No substantive changes to our analysis and conclusions 
within the SSA report were deemed necessary, and we addressed all peer 
reviewer comments in version 1.0 of the SSA report (Service 2023, 
entire).

I. Proposed Listing Determination

Background

    A thorough review of the taxonomy, life history, and ecology of the 
regal fritillary, including both the eastern and western subspecies, is 
presented in the SSA report (Service 2023, pp. 44-68, 180-194). We use 
the term ``species'' to refer to the regal fritillary and any 
information describing or relating to the species applies to both the 
eastern and western subspecies, unless specified otherwise.
    The regal fritillary is a large, nonmigratory butterfly found in 
the grassland habitats of the Fort Indiantown Gap (FTIG) National Guard 
Training Center in Pennsylvania (the eastern subspecies) and portions 
of 14 States, from Indiana to Colorado and from North Dakota to 
Oklahoma (the western subspecies). Adults have dorsal orange forewings 
and dark hindwings that feature black bars, fine white markings, and 
two rows of large spots at the base of the wings. Adults are similar in 
size to the monarch butterfly (Danaus plexippus), with wingspans 
ranging from approximately 6.8 to 10.5 centimeters (cm) (2.67 to 4.13 
inches (in)) (Selby 2007, p. 14); however, the regal fritillary's 
predominately orange forewings and dark hindwings distinguish it from 
other butterflies (Service 2023, p. 44).
    The regal fritillary has one generation per year. In the late 
summer and early fall, females lay eggs that hatch into larvae within 2 
to 3 weeks. The larvae overwinter in nearby grassland vegetation before 
emerging in early spring to search for violets (Viola spp.), their only 
food source (Royer and Marrone 1992, p. 21; Kopper et al. 2000, pp. 
661, 663). In late May through mid-July, the larvae pupate in the leaf 
litter of warm season grasses (Selby 2007, p. 32; Ferster and Vulinec 
2010, p. 7) and emerge as adults beginning in June (Service 2023, pp. 
49, 50). Adults rely on nectar sources for food, and reproductive rates 
improve when nectar plants are abundant and high-quality (Wagner et al. 
1997, p. 268; Selby 2007, p. 33). Adult males live for approximately 4 
to 6 weeks and begin to die off in mid-July; adult females live for 8 
to 12 weeks and may survive into late October (Wagner et al. 1997, p. 
266; Kopper et al. 2001, pp. 174-175; Service 2023, pp. 4, 49).
    Regal fritillary adults are strong and rapid flyers and may move 
long distances in search of nectar (Schweitzer 1989, p. 135; Selby 
2007, p. 26; Service 2023, p. 50). Adults, particularly females, can 
move significant distances, up to 161 kilometers (100 miles), during 
their several-months-long lifespan to access suitable habitats on the 
landscape (Hammond 2021, pers. comm.; Service 2023, p. 50). Individuals 
may disperse to avoid localized threats and poor habitat conditions, 
which allows the species to respond to changing environmental 
conditions and to recolonize suitable habitats, but dispersal depends 
on the availability of nectar and the connectivity and size of the 
available habitats (Schweitzer 1989, p. 135; Selby 2007, p. 26; Hammond 
2021, pers. comm.; Service 2023, pp. 50, 192). Recolonization may fail 
if source populations are too far away or if habitat patches are too 
small, isolated, disconnected, or degraded (Hammond 2021, pers. comm.; 
Service 2023, p. 50).
    The regal fritillary is a landscape-level species that needs large, 
intact grasslands at a landscape scale, and depends on a shifting 
mosaic of large, well-connected, diverse grasslands with violets for 
larvae; nectar sources for adults; and warm season, native bunchgrasses 
for shelter at all life stages (Ferster and Vulinec 2010, p. 39; Caven 
et al. 2017, p. 199; Service 2023, pp. 51, 55). The grasslands need to 
be large and contiguous, generally more than 3.86 square miles (1,000 
hectares), and be maintained by periodic disturbances. Such 
disturbances, which include fire, mowing, and military operations for 
the eastern subspecies, and fire, haying, and grazing for the western 
subspecies, help maintain the grasslands by reducing woody plants and 
encroachment (Service 2023, pp. 4, 8, 69-85).
    However, large, intense or frequent, or permanent disturbances can 
also cause negative individual- or population-level effects, 
particularly during the sedentary, early life stages of the butterfly 
(Service 2023, p. 4). The regal fritillary cannot survive in altered 
landscapes, including row crop fields, nonnative pastures, developed 
areas surrounding prairie remnants (Selby 2007, p. 3), or forests 
(Service 2023, p. 51). As a result, the regal fritillary is considered 
a grassland specialist (Swengel 1996, p. 76) and an indicator of the 
health of native prairie (Royer and Marrone 1992, p. 4; Service 2023, 
p. 51).
    The regal fritillary is also a ``boom-and-bust'' species, which 
means that when environmental conditions and habitat characteristics 
are favorable, significant increases in annual population abundance and 
distribution may occur (Service 2023, pp. 4, 280, 284). When conditions 
are unfavorable, individuals become scarce, and local extirpations may 
occur in areas that may be recolonized when and if conditions improve. 
The ability to disperse over relatively long distances and the boom-
and-bust dynamic helps the species withstand stochastic events, 
catastrophic events, and environmental change. However, the loss and 
fragmentation of grassland habitats can interfere with the boom-and-
bust pattern by isolating populations, contributing to local 
extirpations, and limiting recolonizations.
    The largest and most resilient regal fritillary populations occupy 
large, diverse, contiguous grasslands at a landscape scale. These large 
populations better withstand stochastic events and function as source 
populations for the species to recolonize nearby areas when favorable 
conditions return. Assemblages of regal fritillary populations create a 
metapopulation, which for the regal fritillary includes at least three 
or more populations separated by 32 to 160 kilometers (20 to 100 miles) 
that are linked by infrequent dispersal, are spread over multiple 
habitats and breeding sites, and have some local areas remaining 
occupied despite losses of individual populations. This metapopulation 
structure provides reliable habitat refugia during adverse conditions 
and source populations for recolonizations during favorable conditions 
(Schweitzer 1989, p. 135; Royer and Marrone 1992, p. 26; Service 2023, 
p. 55). Metapopulation-level processes, supported by the species' 
dispersal ability and boom-and-bust dynamic, appear to be critical to 
the long-term persistence of the regal fritillary. However, the 
fragmentation of prairie grasslands across the species' overall range, 
largely the result of conversion to other land uses for the western 
subspecies and woody encroachment for the eastern subspecies, has 
resulted in smaller, more widely separated populations with genetic 
exchange occurring at reduced rates from historical levels. As a 
result, the metapopulation structure is currently absent for the 
eastern subspecies and limited for the western subspecies, particularly 
in the Midwest (Schweitzer 1993, p. 9; Service 2023, p. 55).
    Historically, the regal fritillary was considered common among 
prairie and grassland butterflies in the United States, particularly in 
tallgrass prairie habitats (Hammond and McCorkle

[[Page 63892]]

1983(84), p. 219), with an overall historical range across 32 States 
(Selby 2007, pp. 10, 14; Service 2023, p. 56). But, beginning in the 
1930s and continuing through the 1990s, the species' overall range 
contracted substantially, most severely in the East and Midwest (Wagner 
et al. 1997, pp. 261, 262; Selby 2007, p. 17). Following this decline, 
the eastern subspecies now occupies a small portion of Pennsylvania at 
FTIG, and the western subspecies occupies portions of 14 States 
(Service 2023, p. 57). After 2009, when the last eastern individual was 
observed in Virginia (Chazal 2014, p. 2), FTIG in Pennsylvania became 
the sole remaining site in the East with a known population (Service 
2023, p. 57). Several factors may have contributed to the rapid decline 
of the species in the East, including land use changes, development, 
forest succession, pesticide use, and other activities or events that 
resulted in the collapse of the metapopulation processes (Williams 
1999, p. 3; Schweitzer 1993, p. 9). In the West, the loss of native 
prairie grasslands since the 1800s via conversion to agriculture and 
development had the most significant impact on the regal fritillary 
(Service 2023, pp. 5, 57).
    Taxonomists previously classified the regal fritillary as Speyeria 
idalia, but now classify the species as Argynnis idalia, in the 
subgenus Speyeria. The eastern and western subspecies are genetically 
and morphologically different and are currently separated by 
approximately 869 kilometers (540 miles), from Pennsylvania to Indiana, 
so genetic exchange between the two subspecies is highly unlikely 
(Service 2023, pp. 34, 46). The best available scientific information 
indicates that there are two valid subspecies of regal fritillary: the 
eastern subspecies (A. i. idalia) and the western subspecies (A. i. 
occidentalis) (Williams 2001b, entire; Williams et al. 2003, p. 17; 
Keyghobadi et al. 2013, p. 235; Rutins et al. 2022, p. 4; Service 2023, 
pp. 182-186). We discuss the distribution and trends for each 
subspecies below, with additional information provided in our SSA 
report (Service 2023, entire).

Eastern Regal Fritillary: Distribution and Trends

    The eastern subspecies is currently found as a single population 
located on FTIG. Moisture levels are more mesic (moderately moist) in 
the East than in the West. The eastern subspecies has distinct 
haplotypes that are not present in any other known extant regal 
fritillary population (Williams 2001, pp. 146, 151; Service 2023, pp. 
34, 64). Currently, there are approximately 800 individuals in the 
population at FTIG, and the population exhibits signs of restricted 
gene flow (Keyghobadi et al. 2006, p. 3; Rutins et al. 2022, p. 4; 
Service 2023, pp. 64-65).
    Established in 1931, FTIG has been used continuously for military 
training exercises that periodically disturb the ground and open 
grassland patches, and incidentally help maintain remnant grassland 
patches as an old field, successional stage (Ferster et al. 2008, p. 
142). Without these activities, the remaining grassland habitats for 
the eastern regal fritillary would have converted to forests like the 
surrounding ecoregions (Ferster et al. 2008, p. 142). FTIG also uses 
prescribed burns and mechanical treatments, such as mowing and tree 
cutting, specifically to maintain and improve the eastern subspecies' 
remaining grassland habitats (Ferster and Vulinec 2010, pp. 39, 40; 
Service 2023, p. 52). As a result, the eastern subspecies is found in 
the remaining grasslands at FTIG on approximately 457 acres (185 
hectares) that are the result of military and other activities that 
maintain open areas and promote regal fritillary presence (Zercher et 
al. 2002, p. 13; Service 2023, p. 61). FTIG has monitored the eastern 
subspecies since 1997 (Ferster and Vulinec 2010, p. 31) and conducts 
surveys annually to monitor the population and habitats (Zercher et al. 
2002, pp. M-6-M-8; Pennsylvania Department of Military and Veterans 
Affairs (PADMVA) 2021, entire; Zografou et al. 2021, p. 10; Rutins et 
al. 2022, p. 2). Conservation activities to benefit the eastern 
subspecies at FTIG are conducted through an integrated natural 
resources management plan (INRMP); however, the activities at FTIG that 
benefit the eastern subspecies could change at any time depending on 
funding and priorities (PADMVA 2021, pp. 20, 31; Swartz 2022, pers. 
comm.).

Western Regal Fritillary: Distribution and Trends

    The western subspecies currently occupies portions of 14 States: 
Arkansas, Colorado, Illinois, Indiana, Iowa, Kansas, Minnesota, 
Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Wisconsin, 
and Wyoming. The western subspecies historically occupied a much larger 
portion of the overall species' range than the eastern subspecies. 
Thus, while the eastern subspecies was nearly eliminated with the east-
to-west contraction in the subspecies' range, populations of the 
western subspecies remain where large grasslands are unconverted, 
intact, and contiguous. However, the western subspecies is generally 
considered to have a declining population trend, largely a result of 
land conversion to agriculture and development. Habitat fragmentation 
generally decreases east to west across the western subspecies' range, 
and as the size and number of suitable prairie remnants increases, 
there is a corresponding increase in size, number, and long-term 
viability of the western subspecies' populations (Selby 2007, p. 18).
    The western subspecies occurs in 21 populations, or analytical 
units, as described in the SSA report (Service 2023, pp. 65-67), and 3 
representation units: the Midwest, Northern Great Plains, and Central 
Great Plains. In the Midwest, across Arkansas, Illinois, Indiana, Iowa, 
Minnesota, Missouri, and Wisconsin, western regal fritillary 
populations are now restricted to small, isolated patches of prairie 
remnants that are generally less than 98.9 acres (40 hectares) in size 
(Robertson et al. 1997 in Panzer and Schwartz 2000, p. 363), scattered 
across a landscape primarily dominated by agriculture. To the west, the 
Northern and Central Great Plains are the remaining strongholds for the 
western subspecies, as large, intact grasslands remain. Western regal 
fritillary populations within Kansas, Nebraska, North Dakota, and South 
Dakota are relatively larger and more numerous, due to the less 
fragmented suitable grassland patches compared to those in the Midwest 
(Selby 2007, p. 20). Approximately 84 percent of the western regal 
fritillary's gross, overall range (the outer boundary of all 21 
populations) is privately owned (Service 2023, p. 66). Approximately 7 
percent of this gross, overall range is Tribal, 4 percent is State, 2 
percent is managed by the Bureau of Land Management, 2 percent is 
managed by the U.S. Forest Service, and less than 1 percent each is 
managed by the Service, the Department of Defense, and the National 
Park Service (Service 2023, p. 66).
    The Northern Great Plains and Central Great Plains representation 
units currently support relatively more intact and better-connected 
grasslands, primarily used for livestock grazing or haying, than the 
Midwest unit, but the plains units are drier, are more prone to 
drought, and have fewer tallgrass species comprising the grasslands, 
which may reduce the quality of the habitats for the western regal 
fritillary. The Northern Great Plains representation unit experiences 
shorter growing seasons and colder weather patterns than those in the 
Central Great Plains, which may also reduce the quality of the habitats 
for the western

[[Page 63893]]

regal fritillary. Habitats in the Midwest representation unit are 
primarily small, isolated patches in an agriculturally dominated 
landscape, and many sites exist as conservation preserves, i.e., small 
remnants of the once-vast tallgrass prairie, which may be less than 
suitable for the western regal fritillary (Service 2023, p. 130).
    At the western extent of the western subspecies' overall range, 
grasslands are drier and classified as shortgrass prairie rather than 
tallgrass or mixed grass, which may provide lower quality habitat for 
the western subspecies. As a result, populations tend to be small and 
isolated. Scattered occurrences in the western part of the western 
subspecies' overall range generally occur in riparian zones or other 
moist habitats where nectar sources and violets are available (Selby 
2007, p. 14). The States on both the western and southern fringes of 
the regal fritillary's range, including Arkansas, Colorado, Oklahoma, 
and Wyoming, are sparsely occupied by the western subspecies, with 
individuals occurring only in the portions of those States that border 
adjacent occupied areas in other States, including Kansas and Nebraska. 
Western regal fritillary individuals have been observed in Montana, but 
there are no known populations (Service 2023, p. 56).

Regulatory and Analytical Framework

Regulatory Framework

    Section 4 of the Act (16 U.S.C. 1533) and the implementing 
regulations in title 50 of the Code of Federal Regulations set forth 
the procedures for determining whether a species is an endangered 
species or a threatened species, issuing protective regulations for 
threatened species, and designating critical habitat for endangered and 
threatened species. On April 5, 2024, jointly with the National Marine 
Fisheries Service, we issued a final rule that revised the regulations 
in 50 CFR part 424 regarding how we add, remove, and reclassify 
endangered and threatened species and what criteria we apply when 
designating listed species' critical habitat (89 FR 24300). On the same 
day, we published a final rule revising our protections for endangered 
species and threatened species at 50 CFR 17 (89 FR 23919). These final 
rules are now in effect and are incorporated into the current 
regulations.
    The Act defines an ``endangered species'' as a species that is in 
danger of extinction throughout all or a significant portion of its 
range, and a ``threatened species'' as a species that is likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether any species is an endangered species or a threatened 
species because of any of the following factors:
    (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (B) Overutilization for commercial, recreational, scientific, or 
educational purposes;
    (C) Disease or predation;
    (D) The inadequacy of existing regulatory mechanisms; or
    (E) Other natural or manmade factors affecting its continued 
existence.
    These factors represent broad categories of natural or human-caused 
actions or conditions that could have an effect on a species' continued 
existence. In evaluating these actions and conditions, we look for 
those that may have a negative effect on individuals of the species, as 
well as other actions or conditions that may ameliorate any negative 
effects or may have positive effects.
    We use the term ``threat'' to refer in general to actions or 
conditions that are known to or are reasonably likely to negatively 
affect individuals of a species. The term ``threat'' includes actions 
or conditions that have a direct impact on individuals (direct 
impacts), as well as those that affect individuals through alteration 
of their habitat or required resources (stressors). The term ``threat'' 
may encompass--either together or separately--the source of the action 
or condition or the action or condition itself.
    However, the mere identification of any threat(s) does not 
necessarily mean that the species meets the statutory definition of an 
``endangered species'' or a ``threatened species.'' In determining 
whether a species meets either definition, we must evaluate all 
identified threats by considering the species' expected response and 
the effects of the threats--in light of those actions and conditions 
that will ameliorate the threats--on an individual, population, and 
species level. We evaluate each threat and its expected effects on the 
species, then analyze the cumulative effect of all of the threats on 
the species as a whole. We also consider the cumulative effect of the 
threats in light of those actions and conditions that will have 
positive effects on the species, such as any existing regulatory 
mechanisms or conservation efforts. The Secretary determines whether 
the species meets the definition of an ``endangered species'' or a 
``threatened species'' only after conducting this cumulative analysis 
and describing the expected effect on the species.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis, which is 
further described in the 2009 Memorandum Opinion on the foreseeable 
future from the Department of the Interior, Office of the Solicitor (M-
37021, January 16, 2009; ``M-Opinion,'' available online at https://www.doi.gov/sites/doi.opengov.ibmcloud.com/files/uploads/M-37021.pdf). 
The foreseeable future extends as far into the future as the U.S. Fish 
and Wildlife Service and National Marine Fisheries Service (hereafter, 
the Services) can make reasonably reliable predictions about the 
threats to the species and the species' responses to those threats. We 
need not identify the foreseeable future in terms of a specific period 
of time. We will describe the foreseeable future on a case-by-case 
basis, using the best available data and taking into account 
considerations such as the species' life-history characteristics, 
threat projection timeframes, and environmental variability. In other 
words, the foreseeable future is the period of time over which we can 
make reasonably reliable predictions. ``Reliable'' does not mean 
``certain''; it means sufficient to provide a reasonable degree of 
confidence in the prediction, in light of the conservation purposes of 
the Act.

Analytical Framework

    The SSA report documents the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of the species, including an assessment of the potential 
threats to the species. The SSA report does not represent our decision 
on whether the species should be proposed for listing as an endangered 
or threatened species under the Act. However, it does provide the 
scientific basis that informs our regulatory decisions, which involve 
the further application of standards within the Act and its 
implementing regulations and policies.
    To assess the viability of the eastern and western subspecies of 
regal fritillary, we used the three conservation biology principles of 
resiliency, redundancy, and representation (Shaffer and Stein 2000, pp. 
306-310). Briefly, resiliency is the ability of the species to 
withstand environmental and demographic stochasticity (for example, wet 
or dry, warm or cold years);

[[Page 63894]]

redundancy is the ability of the species to withstand catastrophic 
events (for example, droughts, large pollution events); and 
representation is the ability of the species to adapt to both near-term 
and long-term changes in its physical and biological environment (for 
example, climate conditions, pathogens). In general, species viability 
will increase with increases in resiliency, redundancy, and 
representation (Smith et al. 2018, p. 306). Using these principles, we 
identified the subspecies' ecological requirements for survival and 
reproduction at the individual, population, and subspecies levels, and 
described the beneficial and risk factors influencing the subspecies' 
viability.
    The SSA process can be categorized into three sequential stages. 
During the first stage, we evaluated the subspecies' life-history 
needs. The next stage involved an assessment of the historical and 
current conditions of the subspecies' demographics and habitat 
characteristics, including an explanation of how each subspecies 
arrived at its current condition. The final stage of the SSA involved 
making projections about the subspecies' responses to positive and 
negative environmental and anthropogenic influences. Throughout these 
stages, we used the best available information to characterize 
viability as the ability of a subspecies to sustain populations in the 
wild over time, which we then used to inform our regulatory decision.
    The following is a summary of the key results and conclusions from 
the SSA report; the full SSA report can be found at Docket No. FWS-R6-
ES-2023-0182 on https://www.regulations.gov.

Summary of Biological Status and Threats

    In this discussion, we review the biological condition of the 
eastern and western regal fritillary and their resources, and the 
threats that influence each subspecies' current and future condition, 
in order to assess each subspecies' overall viability and the risks to 
that viability. We analyze these factors both individually and 
cumulatively to determine the current condition of each of the 
subspecies and project the future condition of each subspecies under 
several plausible future scenarios. We begin with a summary of the 
species' needs and risk factors, which are generally similar for both 
subspecies, followed by a summary of conditions first for the eastern 
subspecies and then the western subspecies.

Species Needs

    Eastern and western regal fritillary individuals share many of the 
same needs, including large, contiguous blocks of native grasslands, 
violets to support larvae, warm season bunchgrasses for shelter, and 
nectar sources for adults (Service 2023, pp. 5-8, 69-85), so this 
discussion applies to both the eastern and western subspecies. In 
general, regal fritillary individuals need an adequate abundance of 
violets and nectar sources, appropriate grassland conditions (including 
litter, tall or shrubby cover), warm season bunchgrass tussocks, and 
adequate moisture and ambient temperatures in order to breed, feed, and 
shelter. Grasses are generally native species (indigenous to the 
particular area), and are either tallgrasses or mixed grasses, although 
the eastern regal fritillary may be more tolerant of nonnative grasses 
with similar bunchgrass structure. Ambient temperatures need to be 
suitable, generally between 75 to 105 [deg]F (24 to 41[deg]C) during 
the appropriate season for larvae to grow and for adults to survive 
(McCorkle and Hammond 1988, p. 192; Selby 2007, p. 36; Nail 2016, pp. 
4, 9, 13, 15; Klockmann and Fischer 2017, p. 10872; Service 2023, p. 
76). The grasslands need to be sufficiently large and contiguous (Kelly 
and Debinski 1998, p. 272; Schweitzer 1989, p. 134), ideally more than 
2,471 acres (1,000 hectares) in size, and be maintained by periodic 
disturbances (Service 2023, pp. 8, 70-86).
    The regal fritillary is a landscape-scale (spatially heterogeneous 
geographic areas characterized by diverse interacting patches or 
ecosystems) species, so large, contiguous blocks of native grasslands 
are the species' primary resource need (Service 2023, pp. 4, 55, 81-
86). Large, contiguous grasslands tend to have more variable site 
conditions that support more diverse plant life; their greater area 
encompasses more habitat overall, and they are more likely to exhibit 
the shifting mosaics of heterogeneous habitats that favor sufficiently 
resilient regal fritillary populations. Generally, the larger the 
grassland patch, the better it supports abundant and adequately 
resilient regal fritillary populations, as long as the patch is also 
maintained with periodic disturbance.
    Individuals do not appear to prefer small habitat patches 
(Schweitzer 1989, p. 134), which do not support the required shifting 
resources and disturbance regimes that maintain grassland habitats and 
sufficiently resilient regal fritillary populations. For the western 
subspecies, small habitat patches may be as small as 400 acres (162 
hectares) in size (Hammond 2021, pers. comm; Service 2023, pp. 82-84). 
Small grassland tracts containing regal fritillary colonies may be more 
vulnerable to extirpation than larger blocks of native grasslands, but 
multiple colonies on small patches that are close to one another and 
occur as part of a collectively larger group of habitats may function 
together as a population. When adults in colonies can move across the 
matrix to reach other suitable habitat patches, the collective occupied 
habitats may exhibit diverse conditions that can better support the 
species' life-history needs.
    To be sufficiently resilient, regal fritillary populations need to 
be of adequate size, with at least 200 to 500 adults or more to 
maintain genetic diversity and withstand stochastic events (Service 
2023, p. 89). For redundancy and representation, the species needs 
metapopulation processes supported by an adequate number and 
distribution of sufficiently connected, large populations across the 
large, contiguous grasslands to withstand catastrophic events and adapt 
to environmental change (Service 2023, pp. 7-8, 89-91).

Risk Factors for the Eastern and Western Subspecies

    We reviewed the potential risk factors (i.e., threats, stressors) 
that could be affecting the eastern and western subspecies of regal 
fritillary (Service 2023, pp. 8-11, 93-120, 215-277). Here, we discuss 
only those risk factors in detail that we considered drivers of 
resiliency, or those that could meaningfully affect the status of 
either subspecies. Many of the threats and risk factors are the same or 
similar for both subspecies, so where the effects are expected to be 
similar, we present one summary that applies to both subspecies. Where 
the threats and their effects may be unique to one subspecies, we 
address those specifically.
    Both subspecies are vulnerable to fragmentation and isolation when 
habitats are degraded or lost. The primary risk factors (i.e., threats) 
affecting the status of the eastern subspecies are invasive plants, 
particularly woody encroachment that results in forest succession; 
drought; climate change factors; and periodic disturbances from large 
or intense fire or other activities. The eastern subspecies is 
vulnerable to woody encroachment, and periodic disturbances are 
necessary to ensure the grasslands do not become reforested, but these 
disturbances may

[[Page 63895]]

also present a risk if they are too frequent or intense.
    The primary risk factors (i.e., threats) affecting the status of 
the western subspecies are grassland conversion, primarily due to 
agriculture; herbicides that are applied broadly (often aerially); 
drought; invasive grasses and woody vegetation; periodic disturbances 
from fire, haying, and grazing; and climate change factors (Service 
2023, pp. 10, 119-120). Although disease, predation, parasitism, 
competition and hybridization with sympatric butterflies, and 
collection may affect individuals, we did not find these risk factors 
to be current or future threats to either subspecies. We summarize 
these risk factors below, with additional detail and analysis provided 
in our SSA report (Service 2023, pp. 8-11, 93-120, 215-277).
Grassland Conversion: Agriculture and Development
    This risk factor applies only to the western subspecies. An 
estimated 400 million acres (162 million hectares) of native prairie 
historically existed in North America prior to European settlement in 
the 1800s; these biomes have since been converted primarily to 
agriculture, resulting in as much as a 99.9 percent reduction in native 
prairie ecosystems, with the most severe declines among former 
tallgrass habitats (Samson and Knopf 1994, p. 418; Service 2023, p. 
97). Conversion of grasslands to other uses, such as for agriculture 
and development, reduces the amount, availability, connectedness, size, 
and quality of the native grasslands needed by the regal fritillary 
(Hammond and McCorkle 1983(84), p. 218; Davis et al. 2007, p. 1342; 
Powell et al. 2007, p. 124; Selby 2007, p. 3; Sims 2017, p. 1; Swengel 
and Swengel 2017, p. 2; Marschalek 2020, p. 891; Niemuth et al. 2021, 
p. 2). While agriculture is the dominant activity that has reduced 
North American grasslands, any development activity that removes native 
prairie sod, such as road construction, road maintenance, gravel 
mining, housing and commercial developments, and energy projects, may 
reduce and fragment western regal fritillary habitat (Selby 2007, p. 3; 
Service 2023, pp. 98-100).
    The majority of tallgrass prairie that remains today, particularly 
in the Midwest, is limited to small, isolated remnant tracts that are 
fractions of their former size and extent. Farther west, mixed-grass 
prairie has also been impacted by conversion and other uses; mixed-
grass prairie has been reduced to 30 percent of historical amounts 
(World Rangeland Learning Experience 2021, entire). Much of the mixed-
grass prairie is also fragmented and isolated due to grassland 
conversion. Shortgrass prairies at the western edge of the western 
subspecies' range are the most intact, but western regal fritillary 
populations may not occur there and may instead be found as small, 
ephemeral colonies in scattered moist habitats within these relatively 
dry grasslands (Selby 2007, p. 24).
    Conversion of grasslands to agriculture reduces and fragments 
western regal fritillary habitats and isolates populations, which, when 
they are reduced to small, isolated remnant habitat patches, are 
vulnerable to local extirpations. Remaining grassland patches may be 
too small to support the violets, grasses, and nectar sources needed by 
individuals, and the patches are often surrounded by an unsuitable 
matrix of agriculture and development. Conversion to agriculture and 
development present a barrier to dispersal and gene flow by preventing 
individuals from either attempting to disperse or reducing the 
likelihood that dispersals will result in successful recolonization. 
When dispersals are less successful, recolonizations become less 
likely, genetic diversity declines, inbreeding may suppress population 
expansion, populations are less able to adapt to their changing 
environment, and local extirpations may begin to outpace 
recolonizations (Service 2023, p. 98).
    Agricultural conversion of grasslands occurs at a rate of more than 
1 million acres (404,685 hectares) per year, with projected conversion 
``hotspots'' projected in western regal fritillary habitats in North 
Dakota, South Dakota, Iowa, and Missouri (Lark et al. 2020, p. 3). This 
risk factor to the western regal fritillary is ongoing and projected to 
increase in the future (Service 2023, pp. 96-99, 134, 142, 245-255).
Broad Application of Herbicides
    This risk factor applies only to the western subspecies. Herbicides 
are chemicals that may be used at least once in a growing season to 
control broadleaf weeds or grasses in crop fields. Herbicides are also 
commonly used to control woody vegetation and weeds in both public and 
private grasslands, including native prairie. If not used carefully, 
herbicides can indirectly impact regal fritillary populations by 
eliminating or reducing nectar and foodplants, especially if applied 
during critical periods of the western regal fritillary's lifecycle. 
Adverse effects can occur when herbicides are applied within regal 
fritillary habitat or nearby, where they can drift into western regal 
fritillary habitat (Dana 1997, p. 3; Stark et al. 2012, pp. 25, 27; 
Cordova et al. 2020, p. 5; Service 2023, p. 101). The effects of 
herbicide use may be especially problematic in areas where violets and 
nectar food sources are already limited, such as in small, isolated 
grassland patches. Additionally, herbicide drift from adjacent 
croplands into regal fritillary habitats may have limited and temporary 
effects to individuals and habitats by temporarily reducing the 
availability of violets and nectar sources. Active and inert 
ingredients in herbicides may also be toxic to western regal fritillary 
individuals.
    The application of herbicides is most detrimental to the western 
regal fritillary when it is applied, often aerially, across large areas 
of native grasslands specifically to reduce native forbs, including 
violets, so that more grasses are available to graze livestock. This 
practice dramatically reduces the quantity of violets and nectar 
sources available to the western regal fritillary (Service 2023, pp. 
101-102). This practice of broad herbicide application to reduce native 
forbs is ongoing, particularly on private lands in eastern South 
Dakota, the Flint Hills of Kansas, and Oklahoma (Service 2023, pp. 101-
102). Unlike the potentially limited or temporary effects to habitats 
and individuals from herbicide drift, this practice directly exposes 
native grasslands to herbicides and could dramatically reduce the 
numbers of violets and nectar sources. The reduction and removal of 
violets and nectar sources in native grasslands may extirpate local 
colonies (Selby 2007, p. 36) and, if more widespread, could also 
decrease population abundance and resiliency. This risk factor is 
ongoing and is likely to increase in the future.
Invasive and Woody Plants and Encroachment
    This risk factor applies to both the eastern and western 
subspecies. Invasive, nonnative (exotic) plants and woody vegetation 
may degrade the quality and quantity of native grasslands needed by 
both the eastern and western regal fritillary. These nonnative plants 
may spread into native habitats from purposefully planted areas to form 
self-perpetuating populations (Fulbright et al. 2013, p. 505). The 
invading plant species of concern and the magnitude, scope, and 
exposure to the eastern and western subspecies vary by location. 
Invasive grass species include Kentucky bluegrass (Poa patrensis) and 
smooth brome (Bromus inermus), which are the two primary species 
invading the Midwestern and Northern Great Plains

[[Page 63896]]

prairies (Royer and Marrone 1992, p. 28; Selby 2007, p. 33; Gaskin et 
al. 2021, p. 236-237; Service 2023, pp. 104-105, 256). Woody plant 
species may include eastern red cedar (Juniperus virginiana) for the 
western subspecies and a variety of woody species from the surrounding 
forested habitat at FITG for the eastern subspecies, (Swartz 2021, 
pers. comm.; Service 2023 pp. 105-107; 256). Conservation efforts that 
target invasive plants, which may include fire, grazing, or mechanical 
or chemical controls, may reduce the stressor. However, invasive 
grasses and woody plant encroachment are challenging to control and 
known to degrade native grassland quality and quantity and may become 
more widespread, and potentially problematic, in the future.
    Although an issue for both subspecies, woody encroachment is a 
primary risk factor for the eastern subspecies, where forested 
ecosystems are more prevalent and contributed to the historical decline 
of the eastern subspecies' grassland habitats. At FTIG, prescribed 
fire, mowing, and targeted brush cutting are used frequently to 
suppress shrub and tree sprouts, and without this important vegetation 
management, habitat for the eastern subspecies would be rapidly 
reforested and rendered unsuitable (Service 2023, p. 105). As with 
invasive grasses, over time, the continued degradation due to woody 
encroachment is likely to increasingly fragment and isolate habitats 
and is a risk factor to both the eastern and western subspecies.
Periodic Disturbances: Fire, Haying, Mowing
    This risk factor applies to both the eastern and western 
subspecies, with fire a risk factor for the eastern subspecies and 
fire, haying, and mowing a risk factor for the western subspecies. 
Fire, haying, mowing, and other activities, such as the manual or 
chemical removal of weeds or woody vegetation, are common disturbances 
in grasslands and are necessary to conserve these habitats, but they 
may negatively impact both the eastern and western subspecies (Selby 
2007, p. 3). Unmanaged grasslands may become overgrown, invaded by 
woody vegetation or exotic species, or covered in thatch that inhibits 
floral diversity and suppresses violets and nectar sources. Although 
beneficial at the appropriate frequency, magnitude, and intensity, 
periodic disturbances can trample, crush, burn, or poison individuals, 
and temporarily or permanently remove important resource needs. When 
these periodic disturbances occur in large, contiguous native grassland 
landscapes, mortality typically does not result in population losses, 
as individuals may disperse to adjacent areas and affected habitats may 
eventually be recolonized.
    However, periodic disturbances on smaller, more-isolated patches of 
grasslands, which are now the dominant patch size available for both 
subspecies, may extirpate local populations, and without nearby 
refugia, these disturbances can potentially preclude recolonization or 
cause population impacts lasting several years (Swengel 1996, p. 73). 
Timing and intensity can also determine the level of impact. For 
example, moderate-to-light grazing that maintains native grasslands and 
removes excessive thatch, controls invasive species, and stimulates 
native plant growth, is generally considered beneficial to the regal 
fritillary, but heavy grazing that does not promote native grasslands 
is not (Royer and Marrone 1992, p. 28; Service 2023, p. 110); fires on 
a 3- to 5-year rotation (Henderson et al. 2018, p. 41; McCullough et 
al. 2019, p. 9) may be beneficial, while shorter or longer intervals 
between burns are more detrimental (McCullough et al. 2019, p. 9), 
although annual burns may still provide some benefits to habitat 
compared to no burning (Henderson et al. 2018, p. 41). When applied on 
a landscape scale appropriately (proper timing, extent, intensity, 
frequency), these disturbances can minimize regal fritillary mortality 
while creating a shifting mosaic of habitats in various successional 
stages that provide a net benefit to the species' resiliency. However, 
when applied inappropriately, they pose a threat to both regal 
fritillary individuals and populations, particularly those that are 
already at risk due to other factors, such as their small size and 
isolation.
    Currently, the Midwest populations of the western subspecies, 
because they occur in small, isolated patches, are vulnerable to the 
negative impacts of improperly applied periodic disturbances. Many 
populations in the Great Plains are also small, but the landscape is 
less fragmented; thus, disturbed sites are more easily recolonized when 
favorable vegetative conditions return. However, this could change in 
the future as more conversion and drought reduce and fragment habitats. 
At FTIG, the INRMP guides the periodic disturbances to benefit the 
eastern subspecies, but should these periodic disturbance activities 
stop, the resiliency of the eastern subspecies could decline 
significantly (Service 2023, p. 110).
Drought
    This risk factor applies to both the eastern and western 
subspecies. By reducing precipitation, drought can significantly reduce 
violet and nectar sources, so drought is a risk factor for both the 
eastern and western subspecies. The regal fritillary is sensitive to 
prolonged, dry periods from drought, and population extirpations may 
occur, particularly in small, isolated habitats that lack heterogeneity 
(Service 2023, p. 106). With their long flight period and relatively 
long lifespan, adult regal fritillaries, particularly females, require 
a nearly continuous supply of nectar during summer and fall to survive 
and reproduce (Wagner et al. 1997, p. 266). Drought may decrease the 
availability of the needed flowering nectar plants (Royer and Marrone 
1992, p. 25), so drought may increase an adult's risk of starvation, 
reduce breeding success, and increase risks associated with forced 
emigration in search of food. Spring droughts may reduce the 
availability of violets, so larvae may starve or their growth may be 
stunted (Service 2023, p. 106). Therefore, prolonged and extended 
dryness associated with drought during any season is a risk factor for 
regal fritillary individuals of all life stages. At FTIG in 
Pennsylvania, there is generally more moisture than in the West, so the 
eastern regal fritillary may be less vulnerable to drought than the 
western subspecies.
Climate Change
    Specific impacts of climate change on pollinators are not well 
understood; however, expected changes forecasted for terrestrial 
species and communities include increased ambient temperature, changes 
to annual and seasonal precipitation patterns, increased frequency of 
extreme events, and changes to hydrologic regimes (Staudinger et al. 
2013, p. 466). These climate changes may lead to decreased resource 
availability (due to mismatches in temporal and spatial co-
occurrences), decreased availability and suitability of larval habitat 
(due to increased flooding or storms), and increased stress from 
overheating (due to higher temperatures) (Cohen et al. 2018, p. 226; 
Zografou et al. 2021, p. 3283). Based on the known biology and life 
history of the species, increasingly warmer temperatures may have 
effects such as interruption of winter diapause, which would result in 
energy expenditure and potentially reduced first instar survival; 
alteration of violet and/or nectar plant phenology, availability, or 
abundance, which would impact food resources for

[[Page 63897]]

larval and adult stages; unusual post-winter diapause cold periods, 
which would impact larval survival; and direct mortality of regal 
fritillaries at all life stages due to excessive heat, drought, or 
severe storms. Despite having a wide climatic tolerance based on its 
range, the regal fritillary experiences very large fluctuations in 
annual numbers--even in populations with stable to increasing trends--
suggesting that extreme weather can negatively impact regal fritillary 
abundance (Swengel and Swengel 2017, p. 19). Several populations in 
western Iowa, for example, were extirpated during extreme drought in 
the mid-2010s, with no perceived recovery as of the summer of 2021 
(Hammond 2021, pers. comm.).
    Climate variability may lead to shifts in geographic range, as has 
been reported for regal fritillary populations in Wisconsin and North 
Dakota (Swengel and Swengel 2017, p. 19), as well as decoupling 
pollinators from matching both host plant and nectar plant phenologies 
(Memmott et al. 2007, p. 712), as demonstrated in other butterfly 
species (Forister et al. 2010, pp. 2088-2089; Hickling et al. 2006, p. 
452). Spring larval emergence may rely on suitable temperatures, photo 
period, or a combination of both, leading to larvae emerging when 
violets are older and less palatable. Drier summers could force regal 
fritillaries to leave otherwise suitable habitat in search of nectar 
sources. Other potential effects from climate change include increased 
flooding and storm events, which may directly reduce available larval 
habitat suitability (e.g., violet abundance) (Goulson et al. 2015, p. 
4). Finally, effects from climate change may increase stress on regal 
fritillaries in the future, further compounding pressures from other 
factors, including pathogens, nonnative species, and habitat loss 
(Goulson et al. 2015, pp. 4-5; Kerr et al. 2015, pp. 178-179; Williams 
and Osborne 2009, p. 371).
Summary of Risk Factors for the Eastern and Western Regal Fritillary
    Our analysis of the past, current, and future influences on the 
needs of the eastern regal fritillary for long-term viability revealed 
that invasive plants, woody encroachment, and periodic disturbances 
from fire or other activities pose the greatest impact on the eastern 
subspecies' current and future viability. Drought and associated 
effects of climate change may also influence the viability of the 
eastern regal fritillary. For the western regal fritillary, grassland 
conversion, primarily due to agriculture; herbicides that are applied 
broadly (often aerially); drought; invasives grasses and woody 
vegetation; incompatible periodic disturbances from fire, haying, and 
mowing; and climate change factors pose the greatest impact on the 
western subspecies' current and future viability.

Conservation Efforts and Regulatory Mechanisms

    The State of Pennsylvania does not consider invertebrates for its 
State threatened and endangered species programs, so does not confer 
State-level protections to the eastern regal fritillary. A variety of 
conservation efforts have been and are implemented to benefit the 
eastern regal fritillary at FTIG. Since 2011, a regal fritillary 
captive-rearing program has attempted to reintroduce the eastern regal 
fritillary into suitable habitats off FTIG, although the attempts to 
establish a population have not yet been successful (Service 2023, p. 
113). The INRMP, developed under the Sikes Act, helps guide 
conservation objectives and activities at FTIG specifically for the 
eastern regal fritillary, including increasing or maintaining 
population levels, nectar sources, and larval host plants. Conservation 
actions include extensive seasonal monitoring; habitat management using 
burning, mowing, and brush removal; and reintroduction efforts. 
Additionally, FTIG completed a candidate conservation agreement (CCA) 
to append to the INRMP that helps formally document regal fritillary 
butterfly conservation intentions at the military installation (FITG 
and Service 2024, entire). These conservation efforts have helped 
maintain grassland habitats at FTIG for the eastern subspecies. 
However, these conservation actions in the INRMP and draft CCA are not 
regulatory or binding and could stop with changing funding or 
priorities (PADMVA 2021, pp. 20, 31; Swartz 2022, pers. comm; FITG and 
Service 2024, entire). As a result, there are no binding and 
enforceable regulatory mechanisms that address threats to the eastern 
regal fritillary.
    The States of Indiana and Wisconsin have assigned the western regal 
fritillary State-level protections as an endangered species and the 
State of Illinois recognizes the species as a threatened species 
(Service 2023, p. 179). The States of Iowa, Minnesota and Wyoming 
identify the western regal fritillary as a species of concern (Service 
2023, p. 179. These designations may allow State agencies to develop 
programs to manage and conserve nongame and endangered species, but 
they do not provide binding and enforceable regulatory mechanisms that 
may reduce threats to the western regal fritillary. Additionally, 
conservation measures and actions may occur locally in many areas to 
benefit the western regal fritillary, but most are likely to be 
voluntary and may not be able to ameliorate or mitigate the identified 
threats to the species (Service 2023, pp. 116-117). These actions often 
depend on limited sources of funding and may not necessarily conducted 
with the needs and life history of the regal fritillary in mind and may 
or may not be beneficial to the subspecies (Service 2023, pp. 116-117). 
Appropriate haying, grazing, and burning are generally known to be 
beneficial to regal fritillaries by promoting native grassland 
habitats, and these actions do occur under all types of land ownership. 
However, land use activities conducted without knowledge or 
consideration for the subspecies' life-history and habitat needs can be 
detrimental to individuals and populations, particularly on small, 
isolated habitat patches. Additionally, activities are not typically 
conducted in a coordinated manner among landowners or on a scale large 
enough to improve the resiliency, redundancy, or representation of the 
western subspecies.

Current Condition of the Eastern Regal Fritillary

    To evaluate resiliency for the eastern regal fritillary, we 
evaluated the current condition of several habitat factors (native 
grasslands, riparian and wetland areas, ambient temperature, 
precipitation) and two demographic factors (population trend and 
abundance) (Service 2023, pp. 120-131). Currently, the eastern regal 
fritillary is found in one population, and based on our evaluation of 
the habitat and demographic factors, that single population currently 
has low resiliency and provides the subspecies' redundancy and 
representation. The single population is found on FTIG military base in 
Pennsylvania, where ongoing management activities to benefit the 
subspecies are conducted through an INRMP on approximately 457 acres 
(185 hectares). These management activities have helped maintain 
grassland habitats for the eastern regal fritillary, such that many of 
the available habitats are in good condition. FITG has monitored the 
eastern regal fritillary on the military base since 1992 (Ferster 2005, 
p. 8). The population peaked in 2014 with approximately 5,400 
individuals, but declined starting in 2017 to approximately 800 
individuals, and the population size has never rebounded to its high 
numbers from 2014 (Swartz 2022, pers. comm.; Service 2023, p. 64). As a 
result, the abundance and growth trend are currently both in very low

[[Page 63898]]

condition, so the eastern subspecies has low resiliency (Service 2023, 
pp. 123, 126-128). Additionally, military activities and periodic 
disturbance activities such as fire, which can benefit the eastern 
subspecies by reducing woody encroachment, may also present a risk to 
the subspecies if they are discontinued or if they are too frequent, 
intense, or catastrophic. Active military exercises and other 
activities occur without consideration of the subspecies elsewhere in 
grassland habitats at FTIG. The eastern subspecies' resiliency and 
redundancy are limited by the condition of the subspecies' small, 
narrowly distributed habitats and depend on the reduction of its 
primary threat, woody encroachment, through management and other 
voluntary activities. The eastern subspecies is different genetically 
and morphologically than the western subspecies, and the east 
representative unit provides a unique, more mesic, ecological type. The 
eastern regal fritillary's small population size, narrow distribution, 
and limited ecological and genetic diversity indicate that the eastern 
subspecies is currently vulnerable to stochastic events, catastrophes, 
and environmental change.

Current Condition of the Western Regal Fritillary

    To evaluate resiliency for the western regal fritillary, we 
evaluated the current condition of several habitat factors (native 
grasslands, riparian and wetland areas, ambient temperature, 
precipitation) and two demographic factors (population trend and 
abundance) (Service 2023, pp. 120-131). Currently, the western 
subspecies has 21 populations, or analytical units in the SSA, 
distributed across 3 representation units, which feature a diversity of 
climates, habitats, and genetics. Based on our evaluation of the 
habitat and demographic factors, of the 21 populations, 3 currently 
have high resiliency, 7 have medium resiliency, 10 have low resiliency, 
and 1 is currently functionally extirpated with no resiliency, although 
it supports habitats and has recent observations (Service 2023, pp. 16, 
124-126). Populations with high resiliency have better habitat and 
demographic conditions than populations with medium or low resiliency, 
so are better able to withstand stochastic events. Populations with 
medium resiliency are about as likely as not to withstand a stochastic 
event, those with low resiliency are less likely to withstand a 
stochastic event, and those with no resiliency are considered 
functionally extirpated, so unlikely to withstand a stochastic event. 
The three populations with high resiliency are in the Northern and 
Central Great Plains representation units, and no populations currently 
have very high or very low resiliency (Service 2023, pp. 16, 128). All 
the populations in the Midwest representation units currently have low 
resiliency because of generally poor habitat conditions following the 
conversion of these areas to agriculture and other development. 
Additionally, populations in the Midwest exhibit relatively less 
genetic diversity than those in the Northern Great Plains or Central 
Great Plains, an indication of their fragmentation and isolation 
(Service 2023, pp. 21, 129). However, across the entire Northern and 
Central Great Plains representation units, based on genetics, the 
western regal fritillary is considered one, large population with high 
gene flow over hundreds of kilometers (Williams et al. 2003, pp. 13, 
14). The 21 populations are distributed across portions of 14 States. 
As a result, the western subspecies currently has levels of resiliency, 
redundancy, and representation that make it less vulnerable to 
extinction.

Future Conditions

    As part of the SSA, we developed three future condition scenarios 
to capture the range of uncertainties regarding future threats to and 
the projected responses of the eastern and western subspecies of regal 
fritillary. Our scenarios included a continuation scenario, which 
incorporated the current risk factors continuing on the same trajectory 
as they are now. We also evaluated two future scenarios that 
incorporated varying levels of increasing risk factors with elevated 
negative effects on populations of the eastern and western subspecies. 
However, because we determined that the current condition of the 
eastern subspecies is consistent with an endangered subspecies (see 
Eastern Subspecies: Determination of Status, below), we are not 
presenting the results of our future conditions analysis for the 
eastern subspecies in this proposed rule. Please refer to the SSA 
report (Service 2023, pp. 132-152) for the full analysis of future 
conditions for both subspecies.
    We projected the future condition of the western subspecies of 
regal fritillary under three plausible future scenarios across the next 
50 years, to approximately 2075. This 50-year timeframe for our future 
projections accounts for approximately 50 annual regal fritillary 
generations and is an adequate time period to assess the response of 
populations to stressors and conservation efforts, given that the 
historical range of the eastern subspecies contracted to its current 
distribution within approximately 50 years. It is also a time period 
for which we can reasonably project climate conditions based on the 
best available climate models across the range of the western 
subspecies.
    The future scenarios described in the SSA report represent three 
possible future conditions based on projected climate conditions and 
plausible states of the threats for the western regal fritillary, as 
summarized in Risk Factors for the Eastern and Western Subspecies, 
above. The future scenarios project the threats into the future and 
consider the impacts those threats could have on the viability of the 
western subspecies. We apply the concepts of resiliency, redundancy, 
and representation to the future scenarios to describe the range of 
plausible future conditions of the western subspecies. Uncertainty is 
inherent in any projection of future condition, so we must consider 
plausible scenarios to make our determinations. When assessing the 
future, viability is not a specific state, but rather a continuous 
measure of the likelihood that the subspecies will sustain populations 
over time.
    We included climate change impacts in our future scenarios as a 
factor that would add to the negative effects of the primary threats to 
the western subspecies and its habitat. Climate change is expected to 
increase ambient temperatures, reduce precipitation, and increase the 
frequency and duration of drought across the overall range of the 
western subspecies. Warmer ambient temperatures may interrupt winter 
diapause, which would result in energy expenditure and potentially 
reduced first instar survival; alter violet and nectar plant phenology, 
availability, or abundance, which would impact food resources for 
larvae and adults; result in unusual post-winter diapause cold periods, 
which would impact larval survival; and direct mortality of regal 
fritillaries at all life stages due to excessive heat, drought, or 
severe storms. Increased frequency and duration of drought may reduce 
the availability of violets and nectar sources. We used the best 
available climate data and models, including representative 
concentration pathways (RCPs) 4.5 and 8.5 and underlying temperature 
and precipitation models, to project the plausible outcomes for these 
factors, which were incorporated into our three future scenarios 
(Service 2023, pp. 133-136, 141-143). We summarize the results of our 
future conditions analysis for the western regal fritillary below.

[[Page 63899]]

    Our future scenarios analysis for the western regal fritillary 
revealed that in 50 years, stressors will increase at their current 
rates of increase, or will increase moderately or significantly more 
than their current rates of increase. When stressors continue at their 
current rates, we projected that grassland habitats will continue to 
become smaller, more fragmented, and isolated, such that resiliency 
declines for at least four of the populations in 50 years (Service 
2023, pp. 141-152). Although the number, distribution, and diversity of 
western subspecies populations decline only slightly under this future 
scenario, the scenario still represents increased risk for the western 
subspecies with the declines in resiliency. With a moderate future 
increase in stressors, the quality and quantity of habitats decline 
further such that resiliency declines for up to 11 populations, with 
drops from medium to low resiliency, and some to very low resiliency 
(Service 2023, pp. 141-152). Finally, with the most significant 
projected increase in stressors, 10 of the 21 populations lose 
resiliency and become extirpated, 7 populations have very low 
resiliency, 1 population has low resiliency, and only 3 have medium 
resiliency (Service 2023, pp. 141-152). This future scenario represents 
a large decline in resiliency, redundancy, and representation for the 
western subspecies in 50 years, with a corresponding decline in 
viability. Across all of our plausible future scenarios, our analysis 
revealed that the western regal fritillary is at a greater risk of 
extinction in the future.
    We note that, by using the SSA framework to guide our analysis of 
the scientific information documented in the SSA report, we have 
analyzed the cumulative effects of identified threats and conservation 
actions on the species. To assess the current and future condition of 
the species, we evaluate the effects of all the relevant factors that 
may be influencing the species, including threats and conservation 
efforts. Because the SSA framework considers not just the presence of 
the factors, but the degree to which the factors collectively influence 
risk to the entire species, our assessment integrates the cumulative 
effects of the factors and replaces a standalone cumulative-effects 
analysis.

Determination of Status

    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures for determining 
whether a species meets the definition of an endangered species or a 
threatened species. The Act defines an ``endangered species'' as a 
species in danger of extinction throughout all or a significant portion 
of its range, and a ``threatened species'' as a species likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range. The Act requires that we 
determine whether a species meets the definition of an endangered 
species or a threatened species because of any of the following 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence.

Status Throughout All of Its Range

    After evaluating threats to the eastern and western regal 
fritillary and assessing the cumulative effect of the threats under the 
Act's section 4(a)(1) factors, we found that both subspecies have 
declined in overall abundance and distribution. Historically, 
populations of the regal fritillary functioned on a vast, 
metapopulation scale and were abundant and broadly distributed, 
particularly in the Midwest and Great Plains. Millions of individuals 
likely occupied the North American prairies prior to establishment of 
European agriculture in the 1800s (Hammond and McCorkle 1983(84), p. 
219). Natural disturbance processes including climate, grazing, and 
fire maintained the open grassland habitats, and there were enough 
violet and nectar components for the regal fritillary. This vast range 
may have facilitated an eastward range expansion, perhaps via coastal 
grasslands, where the regal fritillary opportunistically moved into 
inland habitats created and maintained by human activities (Service 
2023, p. 131).
    Today, grassland patches of adequate size, diversity, and 
connectivity are significantly reduced, both in number and proximity, 
interrupting the landscape-level scales at which the regal fritillary 
historically functioned. Accessibility to suitable habitats has become 
increasingly restrictive for the eastern and western regal fritillary, 
as many remaining suitable grassland patches are small and isolated, 
primarily the result of conversion in the West and woody encroachment 
in the East. The eastern subspecies is extirpated from nearly every 
formerly known occupied eastern location and is confined to one small 
population that is extremely vulnerable to environmental and 
demographic stochasticity. For the western subspecies, a small 
fraction, less than one percent, of the historically vast tallgrass 
prairies of the Midwest remains today, mostly as grassland remnants 
that are severely fragmented and isolated (Samson and Knopf 1994, p. 
418, Service 2023, p. 97). Conditions at the westernmost extent of the 
western subspecies' overall range are currently not as severe, as large 
mixed-grass prairies remain, but much of these grasslands have been or 
could be converted to agriculture and other development. In the future, 
the climate in the West is projected to be drier and warmer, and 
important resource needs, such as violets and native grasses, may 
become limited. Without large, intact, contiguous grasslands, 
dispersals of individuals from occupied habitats are often already dead 
ends, as individuals move into a matrix that may be composed of 
unsuitable agricultural fields where they are unable to find the 
resources they need to survive and establish the next annual 
generation. For both the eastern and western subspecies, the risk of 
genetic collapses increases without regular successful dispersal 
events, and the eastern regal fritillary has already experienced 
restricted gene flow. The western regal fritillary has reduced genetic 
diversity in the Midwest. Natural periodic disturbances that 
historically maintained the shifting mosaic of habitats on the 
landscape scale have been replaced with permanent land use changes and 
land use management regimes that, when applied inappropriately, have 
reduced or eliminated regal fritillary populations. As a result, both 
subspecies are increasingly vulnerable to stochastic events and 
synergistic processes that have significantly greater potential to 
cause population extirpations that may outpace recolonization rates.

Eastern Subspecies: Status Throughout All of Its Range

    The eastern regal fritillary has declined significantly in overall 
distribution and abundance since the 1930s. Once broadly distributed 
across the eastern United States, the eastern subspecies is now found 
only in one population on approximately 457 acres (185 hectares) of 
remnant grasslands on FTIG in Pennsylvania. Due to the small size of 
the occupied habitats and the single population, the eastern regal 
fritillary currently has low resiliency, limited redundancy, and 
reduced ecological and genetic diversity (representation). As a result, 
the eastern subspecies is vulnerable to stochastic and catastrophic 
events, such as hot and dry summers, long and cold winters, and 
destructive fires. The eastern

[[Page 63900]]

subspecies' low level of resiliency, coupled with its limited 
redundancy and representation and ongoing and immediate threats 
currently results in a high risk of extinction for the eastern regal 
fritillary.
    The remaining eastern subspecies' grassland habitats at FTIG depend 
on the ongoing reduction of woody encroachment through active 
management. These activities are critical to the viability of the 
eastern regal fritillary and have helped ensure that the eastern 
subspecies remains in this area in contrast to its historical 
extirpation throughout much of its overall range. Active management at 
FTIG, whether intentional or unintentional, has reduced and continues 
to reduce habitat loss and fragmentation from woody encroachment, such 
that FTIG is now the lone site where the eastern subspecies is still 
found. Although conservation activities at FTIG are ongoing and have 
benefited the eastern subspecies by maintaining grassland habitats, 
they are implemented only in specific areas and could stop or change at 
any time depending on funding and priorities, thus increasing the 
subspecies' vulnerability. Military activities and periodic disturbance 
activities such as fire, which can benefit the eastern subspecies by 
reducing woody encroachment, may also present a risk to the subspecies 
if they are discontinued or if they are too frequent, intense, or 
catastrophic. As a result, the eastern regal fritillary is vulnerable 
to extinction, not only because of its limited abundance, distribution, 
and diversity, but also by its complete reliance on important and 
effective land management activities that are not guaranteed to 
continue.
    Our analysis of the eastern subspecies' current condition, as well 
as the conservation efforts discussed above, show that the eastern 
regal fritillary is in danger of extinction throughout all of its range 
due to the severity and immediacy of threats currently impacting its 
single population (see Risk Factors for the Eastern and Western 
Subspecies, above). The single population is isolated, has limited 
potential for natural recolonization, and has a high risk of 
extirpation from stochastic and catastrophic events, so the risk of 
extinction for the eastern regal fritillary is high; therefore, the 
species meets the definition of an endangered species and is not a 
threatened species.

Eastern Subspecies: Status Throughout a Significant Portion of Its 
Range

    Under the Act and our implementing regulations, a subspecies may 
warrant listing if it is in danger of extinction or likely to become so 
within the foreseeable future throughout all or a significant portion 
of its range. We have determined that the eastern subspecies of regal 
fritillary is in danger of extinction throughout all of its range and 
accordingly did not undertake an analysis of any significant portion of 
its range. Because the eastern subspecies of regal fritillary warrants 
listing as endangered throughout all of its range, our determination 
does not conflict with the decision in Center for Biological Diversity 
v. Everson, 435 F. Supp. 3d 69 (D.D.C. 2020) (Everson), which vacated 
the provision of the Final Policy on Interpretation of the Phrase 
``Significant Portion of Its Range'' in the Endangered Species Act's 
Definitions of ``Endangered Species'' and ``Threatened Species'' 
(hereafter ``Final Policy''; 79 FR 37578, July 1, 2014) that provided 
that if the Service had determined that a species was threatened 
throughout all of its range, the Service would not analyze whether the 
species was endangered in a significant portion of its range.

Eastern Subspecies: Determination of Status

    Our review of the best available scientific and commercial 
information indicates that the eastern regal fritillary meets the Act's 
definition of an endangered species. Therefore, we propose to list the 
eastern regal fritillary as an endangered species in accordance with 
sections 3(6) and 4(a)(1) of the Act.

Western Subspecies: Status Throughout All of Its Range

    Currently, the western regal fritillary has 21 populations 
distributed across portions of 14 States and 3 representation units, 
which feature a diversity of climates, habitats, and genetics. Three 
populations have high resiliency, 7 have medium resiliency, 10 have low 
resiliency, and 1 has no resiliency. All the populations in the Midwest 
representative unit currently have low resiliency following the 
conversion of grasslands to agriculture and development. Populations in 
North and South Dakota, eastern Montana, eastern Wyoming, the Sandhills 
in west-central Nebraska, and the Flint Hills in eastern Kansas, 
currently have high resiliency, because of the high-quality condition 
of their habitat and demographic factors. Genetic exchange occurs 
across much of the Northern and Central Great Plains, indicating that 
enough suitable habitats currently remain such that dispersals and 
recolonizations help maintain the landscape-level metapopulation 
structure for the western regal fritillary.
    We considered whether the western regal fritillary is presently in 
danger of extinction throughout all of its range and determined that it 
is not. The current conditions as assessed in our SSA report show that 
there are three populations with high resiliency and seven populations 
with medium resiliency distributed broadly across two large 
representation units. There are an additional eight populations in the 
Midwest representation unit with low resiliency and reduced ecological 
and genetic diversity, so although this area contributes less to the 
overall viability of the western subspecies, it still provides some 
resiliency and redundancy for the subspecies. Across all three 
representation units, there are multiple, sufficiently resilient 
populations distributed across a large, ecologically diverse area. As a 
result, the western regal fritillary currently has sufficient 
resiliency, redundancy, and representation to withstand stochastic and 
catastrophic events and environmental change. Although threats are 
currently acting on the western subspecies and many of those threats 
are expected to continue into the future, we did not find that the 
subspecies is currently in danger of extinction throughout all of its 
range.
    In the future, as stressors, such as conversion to agriculture, 
invasive plants, and drought, continue to reduce the quality and 
quantity of native grasslands, we expect western regal fritillary 
populations to be at an increased risk of extirpation. We project the 
least amount of decline in the western subspecies' viability if the 
stressors continue at their current rates and the greatest decline if 
stressors increase significantly. Across all of our future projections, 
fewer populations will have high and medium resiliency, with increases 
in the number and distribution of populations with low, very low, or no 
resiliency (extirpation). With increasing threats in the future, 
grassland habitats will become smaller, more isolated, and more 
fragmented, and individuals will be less able to disperse and 
recolonize, so we project overall declines in the resiliency, 
redundancy, and representation of the western subspecies in 50 years. 
As a result, we expect that, in the foreseeable future, the western 
regal fritillary will be at an increased risk of extirpation.
    According to our assessment of plausible future scenarios in the 
SSA

[[Page 63901]]

report, the western subspecies is likely to become an endangered 
subspecies within the foreseeable future of 50 years throughout all of 
its range. Our future scenarios help address future uncertainty by 
describing plausible outcomes for the primary risk factors to the 
western subspecies. Fifty years encompasses 50 annual generations of 
the western regal fritillary and a time period when stressors are 
reasonably expected to change and we can make reasonably reliable 
predictions about the threats and the western regal fritillary's 
responses to those threats. In the foreseeable future, we expect more 
grasslands to be converted to agriculture and development and to become 
drier, as ambient temperatures increase and droughts increase in 
intensity, magnitude, and frequency. We expect increases in invasive 
plants, broad herbicide application, and periodic disturbances. As a 
result, we expect additional reductions in the size and distribution of 
large, intact blocks of grasslands and the underlying resources needed 
by the western regal fritillary, including violets, bunch grasses, and 
nectar sources. Violets and nectar sources become more scarce as 
herbicides are broadly applied to reduce forbs in the remaining tracts 
of grasslands. Climate change could further exacerbate the effects of 
drought. As habitats become smaller and more isolated, metapopulation 
processes could fail, with subsequent declines in the resiliency of the 
remaining populations of the western subspecies, as well as the 
redundancy and representation of the subspecies, and we expect the 
western regal fritillary to become more vulnerable to stochastic and 
catastrophic events and environmental change. Therefore, the western 
regal fritillary is likely to become an endangered subspecies within 
the foreseeable future throughout all of its range.
    After evaluating threats to the western subspecies and assessing 
the cumulative effect of the threats under the Act's section 4(a)(1) 
factors, we find that the viability of the western subspecies will 
continue to decline in the next 50 years so that the subspecies is 
likely to become in danger of extinction within the foreseeable future 
throughout all of its range due to the projected loss and fragmentation 
of grassland habitats from conversion to agriculture and development, 
drought, invasive and woody plants, the broad application of 
herbicides, and the synergistic effects of these threats with climate 
change. Thus, after assessing the best available information, we 
conclude that the western subspecies of regal fritillary is not 
currently in danger of extinction but is likely to become in danger of 
extinction within the foreseeable future throughout all of its range.

Western Subspecies: Status Throughout a Significant Portion of Its 
Range

    Under the Act and our implementing regulations, a species may 
warrant listing if it is in danger of extinction or likely to become so 
in the foreseeable future throughout all or a significant portion of 
its range. The court in Center for Biological Diversity v. Everson, 435 
F. Supp. 3d 69 (D.D.C. 2020) (Everson), vacated the provision of the 
Final Policy on Interpretation of the Phrase ``Significant Portion of 
Its Range'' in the Endangered Species Act's Definitions of ``Endangered 
Species'' and ``Threatened Species'' (hereafter ``Final Policy''; 79 FR 
37578, July 1, 2014) that provided if the Services determine that a 
species is threatened throughout all of its range, the Services will 
not analyze whether the species is endangered in a significant portion 
of its range.
    Therefore, we proceed to evaluating whether the western subspecies 
is endangered in a significant portion of its range--that is, whether 
there is any portion of the western subspecies' range for which both 
(1) the portion is significant; and (2) the subspecies is in danger of 
extinction in that portion. Depending on the case, it might be more 
efficient for us to address the ``significance'' question or the 
``status'' question first. We can choose to address either question 
first. Regardless of which question we address first, if we reach a 
negative answer with respect to the first question that we address, we 
do not need to evaluate the other question for that portion of the 
subspecies' range.
    Following the court's holding in Everson, we now consider whether 
there are any significant portions of the western subspecies' range 
where the subspecies is in danger of extinction now (i.e., endangered). 
In undertaking this analysis for the western regal fritillary, we 
choose to address the status question first--we consider information 
pertaining to the geographic distribution of the western subspecies and 
the threats that it faces to identify portions of the range where the 
western regal fritillary may be endangered.
    We evaluated the range of the western regal fritillary to determine 
if the subspecies is in danger of extinction now in any portion of its 
range. The range of a subspecies can theoretically be divided into 
portions in an infinite number of ways. We focused our analysis on 
portions of the western subspecies' range that may be in danger of 
extinction (i.e., meet the Act's definition of an endangered species). 
For the western regal fritillary, we considered whether the threats or 
their effects on the subspecies are greater in any biologically 
meaningful portion of the subspecies' range than in other portions, 
such that the subspecies is in danger of extinction now in that 
portion.
    We examined the range of the western subspecies for biologically 
meaningful portions that may be at a higher risk of extirpation, as 
reflected by current resiliency of the 21 populations. Currently, 10 of 
the 21 populations have low resiliency, so they are at a greater risk 
of extirpation than the populations with more resiliency. These 10 
populations are geographically concentrated along the eastern edge of 
the western subspecies' overall range. Eight of these populations with 
low resiliency make up the Midwest representation unit, which was 
historically dominated by vast tallgrass prairies, but today is an 
agriculturally dominated landscape with prairie remnants existing 
primarily as small, isolated patches. The other two populations 
currently with low resiliency, the Lake Agassiz Plain and Ozark 
Highlands populations, immediately adjoin the Midwest representation 
unit, so were included in our potential portion.
    We then considered whether this biologically meaningful portion of 
10 populations with low resiliency may be at a higher risk of 
extirpation. We examined the following threats, for the reasons 
described above: grassland conversion, invasive plants, broad 
application of herbicides, periodic disturbances, drought, climate 
change, and cumulative effects. We concluded that although the 
populations in this portion have low resiliency, largely the result of 
low and very low conditions of the large, contiguous blocks of native 
grasslands, reproduction and recolonization still occurs with abundance 
and growth trends ranging from low to medium conditions (Service 2023, 
p. 125). Additionally, the portion has sufficient redundancy and 
representation across the 10 populations such that it is not currently 
in danger of extinction. The 10 populations cover a wide geographic 
area that spans portions of 6 States across a variety of climatic and 
habitat types from north-to-south and east-to-west, such that there is 
no stochastic or catastrophic event that would extirpate the portion in 
the near term. Therefore, we conclude that the portion does not have a 
different status from the remainder of the western subspecies' range. 
Because we

[[Page 63902]]

determined that this portion does not have a different status, we did 
not need to assess its potential significance. As a result, we found no 
portion of the western subspecies' range where the biological condition 
of the subspecies differs from its condition elsewhere in its range 
such that the status of the subspecies in that portion differs from any 
other portion of the subspecies' range.
    Therefore, no portion of the western subspecies' range provides a 
basis for determining that the subspecies is in danger of extinction in 
a significant portion of its range, and we determine that the western 
regal fritillary is likely to become in danger of extinction within the 
foreseeable future throughout all of its range. This does not conflict 
with the courts' holdings in Desert Survivors v. U.S. Department of the 
Interior, 321 F. Supp. 3d 1011, 1070-74 (N.D. Cal. 2018) and Center for 
Biological Diversity v. Jewell, 248 F. Supp. 3d 946, 959 (D. Ariz. 
2017) because, in reaching this conclusion, we did not apply the 
aspects of the Final Policy, including the definition of 
``significant'' that those court decisions held to be invalid.

Western Subspecies: Determination of Status

    Our review of the best available scientific and commercial 
information indicates that the western subspecies of regal fritillary 
meets the Act's definition of a threatened species. Therefore, we 
propose to list the western subspecies of regal fritillary as a 
threatened species in accordance with sections 3(20) and 4(a)(1) of the 
Act.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened species under the Act include recognition as a listed 
species, planning and implementation of recovery actions, requirements 
for Federal protection, and prohibitions against certain practices. 
Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies, 
including the Service, and the prohibitions against certain activities 
are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Section 4(f) of the Act calls for the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The goal of this process is to restore listed 
species to a point where they are secure, self-sustaining, and 
functioning components of their ecosystems.
    The recovery planning process begins with development of a recovery 
outline made available to the public soon after a final listing 
determination. The recovery outline guides the immediate implementation 
of urgent recovery actions while a recovery plan is being developed. 
Recovery teams (composed of species experts, Federal and State 
agencies, nongovernmental organizations, and stakeholders) may be 
established to develop and implement recovery plans. The recovery 
planning process involves the identification of actions that are 
necessary to halt and reverse the species' decline by addressing the 
threats to its survival and recovery. The recovery plan identifies 
recovery criteria for review of when a species may be ready for 
reclassification from endangered to threatened (``downlisting'') or 
removal from protected status (``delisting''), and methods for 
monitoring recovery progress. Recovery plans also establish a framework 
for agencies to coordinate their recovery efforts and provide estimates 
of the cost of implementing recovery tasks. Revisions of the plan may 
be done to address continuing or new threats to the species, as new 
substantive information becomes available. The recovery outline, draft 
recovery plan, final recovery plan, and any revisions will be available 
on our website as they are completed (https://www.fws.gov/program/endangered-species), or from our Pennsylvania or South Dakota 
Ecological Services Field Offices (see FOR FURTHER INFORMATION 
CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their ranges may occur primarily or solely on 
non-Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    If these subspecies are listed, funding for recovery actions will 
be available from a variety of sources, including Federal budgets, 
State programs, and cost-share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the State of Pennsylvania would be 
eligible for Federal funds to implement management actions that promote 
the protection or recovery of the eastern regal fritillary. The States 
of Arkansas, Colorado, Illinois, Indiana, Iowa, Kansas, Minnesota, 
Missouri, Nebraska, North Dakota, Oklahoma, South Dakota, Wisconsin, 
and Wyoming would be eligible for Federal funds to implement management 
actions that promote the protection or recovery of the western regal 
fritillary. Information on our grant programs that are available to aid 
species recovery can be found at: https://www.fws.gov/service/financial-assistance.
    Although the eastern and western regal fritillary are only proposed 
for listing under the Act at this time, please let us know if you are 
interested in participating in recovery efforts for these subspecies. 
Additionally, we invite you to submit any new information on these 
subspecies whenever it becomes available and any information you may 
have for recovery planning purposes (see FOR FURTHER INFORMATION 
CONTACT).
    Section 7 of the Act is titled, ``Interagency Cooperation'' and 
mandates all Federal action agencies to use their existing authorities 
to further the conservation purposes of the Act and to ensure that 
their actions are not likely to jeopardize the continued existence of 
listed species or adversely modify critical habitat. Regulations 
implementing section 7 are codified at 50 CFR part 402.
    Section 7(a)(2) states that each Federal action agency shall, in 
consultation with the Secretary, ensure that any action they authorize, 
fund, or carry out is not likely to jeopardize the continued existence 
of a listed species or result in the destruction or adverse 
modification of designated critical habitat. Each Federal agency shall 
review its action at the earliest possible time to determine whether it 
may affect listed species or critical habitat. If a determination is 
made that the action may affect listed species or critical habitat, 
formal consultation is required (see 50 CFR 402.14(a)), unless the 
Service concurs in writing that the action is not likely to adversely 
affect listed species or critical

[[Page 63903]]

habitat. At the end of a formal consultation, the Service issues a 
biological opinion containing its determination of whether the Federal 
action is likely to result in jeopardy or adverse modification.
    In contrast, section 7(a)(4) of the Act requires Federal agencies 
to confer with the Service on any action which is likely to jeopardize 
the continued existence of any species proposed to be listed under the 
Act or result in the destruction or adverse modification of critical 
habitat proposed to be designated for such species. Although the 
conference procedures are required only when an action is likely to 
result in jeopardy or adverse modification, action agencies may 
voluntarily confer with the Service on actions that may affect species 
proposed for listing or critical habitat proposed to be designated. In 
the event that the subject species is listed or the relevant critical 
habitat is designated, a conference opinion may be adopted as a 
biological opinion and serve as compliance with section 7(a)(2) of the 
Act.
    Examples of discretionary actions for the eastern and western regal 
fritillary that may be subject to conference and consultation 
procedures under section 7 are land management or other landscape-
altering activities on Federal lands administered by the Natural 
Resources Conservation Service, the Bureau of Land Management, the 
National Park Service, and the Department of Defense, as well as 
actions on State, Tribal, local, or private lands that require a 
Federal permit (such as a permit from the U.S. Army Corps of Engineers 
under section 404 of the Clean Water Act (33 U.S.C. 1251 et seq.) or a 
permit from the Service under section 10 of the Act) or that involve 
some other Federal action (such as funding from the Federal Highway 
Administration, Federal Aviation Administration, or Federal Emergency 
Management Agency). Federal actions not affecting listed species or 
critical habitat--and actions on State, Tribal, local, or private lands 
that are not federally funded, authorized, or carried out by a Federal 
agency--do not require section 7 consultation. Federal agencies should 
coordinate with the local Service Field Office (see FOR FURTHER 
INFORMATION CONTACT) with any specific questions on section 7 
consultation and conference requirements.
    The Act and its implementing regulations set forth a series of 
general prohibitions and exceptions that apply to endangered wildlife. 
The prohibitions of section 9(a)(1) of the Act, and the Service's 
implementing regulations codified at 50 CFR 17.21, make it illegal for 
any person subject to the jurisdiction of the United States to commit, 
to attempt to commit, to solicit another to commit or to cause to be 
committed any of the following: (1) import endangered wildlife into, or 
export from, the United States; (2) take (which includes harass, harm, 
pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to 
attempt to engage in any such conduct) endangered wildlife within the 
United States or on the high seas; (3) possess, sell, deliver, carry, 
transport, or ship, by any means whatsoever, any such wildlife that has 
been taken illegally; (4) deliver, receive, carry, transport, or ship 
in interstate or foreign commerce in the course of commercial activity; 
or (5) sell or offer for sale in interstate or foreign commerce. 
Certain exceptions to these prohibitions apply to employees or agents 
of the Service, the National Marine Fisheries Service, other Federal 
land management agencies, and State conservation agencies.
    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. Regulations 
governing permits for endangered wildlife are codified at 50 CFR 17.22. 
With regard to endangered wildlife, a permit may be issued for 
scientific purposes, for enhancing the propagation or survival of the 
species, or for take incidental to otherwise lawful activities. The 
statute also contains certain exemptions from the prohibitions, which 
are found in sections 9 and 10 of the Act.

II. Protective Regulations Under Section 4(d) of the Act

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the Secretary shall issue such regulations as she deems 
necessary and advisable to provide for the conservation of species 
listed as threatened species. Conservation is defined in the Act to 
mean the use of all methods and procedures which are necessary to bring 
any endangered species or threatened species to the point at which the 
measures provided pursuant to the Act are no longer necessary. 
Additionally, the second sentence of section 4(d) of the Act states 
that the Secretary may by regulation prohibit with respect to any 
threatened species any act prohibited under section 9(a)(1), in the 
case of fish or wildlife, or section 9(a)(2), in the case of plants. 
With these two sentences in section 4(d), Congress delegated broad 
authority to the Secretary to determine what protections would be 
necessary and advisable to provide for the conservation of threatened 
species, and even broader authority to put in place any of the section 
9 prohibitions for a given species.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld, as a valid 
exercise of agency authority, rules developed under section 4(d) that 
included limited prohibitions against takings (see Alsea Valley 
Alliance v. Lautenbacher, 2007 WL 2344927 (D. Or. 2007); Washington 
Environmental Council v. National Marine Fisheries Service, 2002 WL 
511479 (W.D. Wash. 2002)). Courts have also upheld 4(d) rules that do 
not address all of the threats a species faces (see State of Louisiana 
v. Verity, 853 F.2d 322 (5th Cir. 1988)). As noted in the legislative 
history when the Act was initially enacted, ``once an animal is on the 
threatened list, the Secretary has an almost infinite number of options 
available to [her] with regard to the permitted activities for those 
species. [She] may, for example, permit taking, but not importation of 
such species, or [she] may choose to forbid both taking and importation 
but allow the transportation of such species'' (H.R. Rep. No. 412, 93rd 
Cong., 1st Sess. 1973).
    The provisions of this species' proposed protective regulations 
under section 4(d) of the Act are one of the many tools that we would 
use to promote the conservation of the western regal fritillary. 
Nothing in 4(d) rules change in any way the recovery planning 
provisions of section 4(f) of the Act, the consultation requirements 
under section 7 of the Act, or the ability of the Service to enter into 
partnerships for the management and protection of the western regal 
fritillary. As mentioned previously in Available Conservation Measures, 
section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they authorize, fund, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species. In 
addition, even before the listing of any species or the designation of 
its critical habitat is finalized, section 7(a)(4) of the Act requires 
Federal agencies to confer with the Service on any agency action which 
is likely to jeopardize the continued existence of any species proposed 
to be listed under the Act or result in the destruction or adverse 
modification of critical habitat

[[Page 63904]]

proposed to be designated for such species. These requirements are the 
same for a threatened species regardless of what is included in its 
4(d) rule.
    Section 7 consultation is required for Federal actions that ``may 
affect'' a listed species regardless of whether take caused by the 
activity is prohibited or excepted by a 4(d) rule (``blanket rule'' or 
species-specific 4(d) rule). A 4(d) rule does not change the process 
and criteria for informal or formal consultations and does not alter 
the analytical process used for biological opinions or concurrence 
letters. For example, as with an endangered species, if a Federal 
agency determines that an action is ``not likely to adversely affect'' 
a threatened species, this will require the Service's written 
concurrence (50 CFR 402.13(c)). Similarly, if a Federal agency 
determinates that an action is ``likely to adversely affect'' a 
threatened species, the action will require formal consultation with 
the Service and the formulation of a biological opinion (50 CFR 
402.14(a)). Because consultation obligations and processes are 
unaffected by 4(d) rules, we may consider developing tools to 
streamline future intra-Service and inter-Agency consultations for 
actions that result in forms of take that are not prohibited by the 
4(d) rule (but that still require consultation). These tools may 
include consultation guidance, Information for Planning and 
Consultation effects determination keys, template language for 
biological opinions, or programmatic consultations.

Provisions of the Proposed 4(d) Rule for the Western Regal Fritillary

    Exercising the Secretary's authority under section 4(d) of the Act, 
we have developed a proposed rule that is designed to address the 
western subspecies' conservation needs. As discussed previously in 
Summary of Biological Status and Threats, we have concluded that the 
western regal fritillary is likely to become in danger of extinction 
within the foreseeable future primarily due to the loss and 
fragmentation of grasslands through conversion by agriculture and 
development, the broadcast application of herbicides, invasive and 
woody plants, periodic disturbances, drought, and the synergistic 
effects of climate change. Section 4(d) requires the Secretary to issue 
such regulations as she deems necessary and advisable to provide for 
the conservation of each threatened species and authorizes the 
Secretary to include among those protective regulations any of the 
prohibitions that section 9(a)(1) of the Act prescribes for endangered 
species. We are not required to make a ``necessary and advisable'' 
determination when we apply or do not apply specific section 9 
prohibitions to a threatened species (In re: Polar Bear Endangered 
Species Act Listing and 4(d) Rule Litigation, 818 F. Supp. 2d 214, 228 
(D.D.C. 2011) (citing Sweet Home Chapter of Cmtys. for a Great Or. v. 
Babbitt, 1 F.3d 1, 8 (D.C. Cir. 1993), rev'd on other grounds, 515 U.S. 
687 (1995))). Nevertheless, even though we are not required to make 
such a determination, we have chosen to be as transparent as possible 
and explain below why we find that, if finalized, the protections, 
prohibitions, and exceptions in this proposed rule as a whole satisfy 
the requirement in section 4(d) of the Act to issue regulations deemed 
necessary and advisable to provide for the conservation of the western 
regal fritillary.
    The protective regulations we are proposing for the western regal 
fritillary incorporate prohibitions from section 9(a)(1) of the Act to 
address the threats to the subspecies. The prohibitions of section 
9(a)(1) of the Act, and implementing regulations codified at 50 CFR 
17.21, make it illegal for any person subject to the jurisdiction of 
the United States to commit, to attempt to commit, to solicit another 
to commit or to cause to be committed any of the following acts with 
regard to any endangered wildlife: (1) import into, or export from, the 
United States; (2) take (which includes harass, harm, pursue, hunt, 
shoot, wound, kill, trap, capture, or collect) within the United 
States, within the territorial sea of the United States, or on the high 
seas; (3) possess, sell, deliver, carry, transport, or ship, by any 
means whatsoever, any such wildlife that has been taken illegally; (4) 
deliver, receive, carry, transport, or ship in interstate or foreign 
commerce, by any means whatsoever and in the course of commercial 
activity; or (5) sell or offer for sale in interstate or foreign 
commerce. This protective regulation includes all of these prohibitions 
because the western regal fritillary is at risk of extinction within 
the foreseeable future and putting these prohibitions in place will 
help to conserve the subspecies' remaining populations, slow its rate 
of decline, and decrease synergistic, negative effects from other 
stressors.
    In particular, this proposed 4(d) rule would provide for the 
conservation of the western regal fritillary by prohibiting the 
following activities, unless they fall within specific exceptions or 
are otherwise authorized or permitted: importing or exporting; take; 
possession and other acts with unlawfully taken specimens; delivering, 
receiving, carrying, transporting, or shipping in interstate or foreign 
commerce in the course of commercial activity; or selling or offering 
for sale in interstate or foreign commerce.
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulations at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Regulating 
take would help preserve the subspecies' remaining populations, slow 
their rate of decline, and decrease synergistic, negative effects from 
other stressors. Therefore, we propose to prohibit take of the western 
regal fritillary, except for take resulting from those actions and 
activities specifically excepted by the 4(d) rule.
    Exceptions to the prohibition on take would include all of the 
general exceptions to the prohibition on take of endangered wildlife, 
as set forth in 50 CFR 17.21 and additional exceptions, as described 
below. Despite these prohibitions regarding threatened species, we may 
under certain circumstances issue permits to carry out one or more 
otherwise-prohibited activities, including those described above. The 
regulations that govern permits for threatened wildlife state that the 
Director may issue a permit authorizing any activity otherwise 
prohibited with regard to threatened species. These include permits 
issued for the following purposes: for scientific purposes, to enhance 
propagation or survival, for economic hardship, for zoological 
exhibition, for educational purposes, for incidental taking, or for 
special purposes consistent with the purposes of the Act (50 CFR 
17.32). The statute also contains certain exemptions from the 
prohibitions, which are found in sections 9 and 10 of the Act.
    In addition, to further the conservation of the species, any 
employee or agent of the Service, any other Federal land management 
agency, the National Marine Fisheries Service, a State conservation 
agency, or a federally recognized Tribe, who is designated by their 
agency or Tribe for such purposes, may, when acting in the course of 
their official duties, take threatened wildlife without a permit if 
such action is necessary to: (i) Aid a sick, injured, or orphaned 
specimen; or (ii) Dispose of a dead specimen; or (iii) Salvage a dead 
specimen that may be useful for scientific study; or (iv) Remove 
specimens that constitute a demonstrable but nonimmediate threat

[[Page 63905]]

to human safety, provided that the taking is done in a humane manner; 
the taking may involve killing or injuring only if it has not been 
reasonably possible to eliminate such threat by live capturing and 
releasing the specimen unharmed, in an appropriate area.
    We recognize the special and unique relationship that we have with 
our State natural resource agency partners in contributing to 
conservation of listed species. State agencies often possess scientific 
data and valuable expertise on the status and distribution of 
endangered, threatened, and candidate species of wildlife and plants. 
State agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we must cooperate to the 
maximum extent practicable with the States in carrying out programs 
authorized by the Act. Therefore, any qualified employee or agent of a 
State conservation agency that is a party to a cooperative agreement 
with us in accordance with section 6(c) of the Act, who is designated 
by his or her agency for such purposes, would be able to conduct 
activities designed to conserve the western regal fritillary that may 
result in otherwise prohibited take without additional authorization.
    The proposed 4(d) rule would also provide for the conservation of 
the western subspecies by excepting otherwise prohibited take 
associated with several activities either intended to incentivize 
conservation actions or that, while they may have some minimal level of 
take of the western regal fritillary, are not expected to rise to the 
level that would have a negative impact (i.e., would have only de 
minimis impacts) on the western subspecies' conservation. We propose to 
except incidental take associated with routine livestock operations, 
livestock grazing, noxious weed control, annual haying and mowing, 
prescribed fire, brush control, and mowing section line rights-of-way 
and recreational trails; we describe each in more detail below. These 
activities are expected to have negligible impacts to the western regal 
fritillary and its habitat.

(1) Routine Livestock Operations

    Incidental take caused by the routine livestock ranching activities 
that are described below and that are implemented on private, State, or 
Tribal lands or on other lands not under Federal jurisdiction (e.g., 
lands owned by county or local governments) would not be prohibited, as 
long as those activities are otherwise legal and conducted in 
accordance with applicable State, Federal, Tribal, and local laws and 
regulations. For the purposes of this proposed 4(d) rule, routine 
livestock ranching activities include (as described below) the 
construction and maintenance of fences, the gathering and management of 
livestock, and the development and maintenance of watering facilities 
for livestock.
(a) Fence Construction and Maintenance
    Fences are an essential tool for livestock and ranch management. In 
addition, the strategic distribution of fencing is also necessary to 
implement multicell rotational grazing systems, which may be necessary 
to improve grazing management and provide a conservation benefit to the 
western regal fritillary's habitat. Therefore, incidental take 
associated with the construction and maintenance of fencing to manage 
livestock and ranches will be excepted.
(b) Livestock Gathering and Management
    The installation and maintenance of corrals, loading chutes, and 
other livestock working facilities are critical to ranch operations. 
These activities may be carried out with only minimal impacts to the 
western regal fritillary. Therefore, incidental take associated with 
livestock gathering and management activities will be excepted.
(c) Development and Maintenance of Livestock Watering Facilities
    Without a suitable water source in a pasture, livestock ranching is 
impossible. The proper distribution of livestock watering sources is 
also a prerequisite to implementing improved grazing management via the 
use of multicell rotational grazing systems that may be necessary to 
conserve western regal fritillary habitat and to provide a conservation 
benefit to the subspecies on grazed sites. This activity includes both 
the initial development of water sources and their maintenance. Dugout 
ponds, for example, typically require a cleanout after 15 to 20 years.

(2) Livestock Grazing

    Incidental take of the western regal fritillary that may result 
from livestock grazing on private, State, or Tribal land would be 
excepted from the take prohibitions of section 9 of the Act. By 
excepting take of the western regal fritillary caused by livestock 
grazing, we acknowledge the positive role that some ranchers have 
played in conserving the western regal fritillary and that grazing can 
be compatible with maintaining remaining native grasslands. Grazing and 
browsing by livestock may improve and maintain regal fritillary habitat 
by removing herbaceous vegetation that shades and competes with violets 
and results in earlier successional stages within the grasslands, 
contributing to the landscape-level mosaic of habitats used by the 
western regal fritillary. Best management practices to make grazing 
compatible with regal fritillary conservation may include light-to-
moderate grazing intensities in the late fall and early spring, patch 
burn grazing methods to maintain a shifting mosaic of habitats and 
prevent woodland encroachment, and avoiding the broadcast spraying of 
herbicides across large areas to kill plants that compete with grasses. 
Recovery of the western regal fritillary will depend on the protection 
and restoration of high-quality habitats supporting violets and nectar 
sources on private lands and on public lands that are grazed by private 
individuals under lease or other agreements. Therefore, incidental take 
associated with livestock grazing on private, State, or Tribal lands, 
including light-to-moderate grazing intensities in the late fall and 
early spring, and patch burn grazing methods that may help maintain an 
annually shifting mosaic of fire and grazing across a landscape to 
increase the diversity and structure of vegetation will be excepted.

(3) Noxious Weed Control

    State and county laws require landowners to control noxious weeds 
on their property, and the timing of control actions is usually 
dependent on the growth stage of the weed species. Control of noxious 
weeds may also be important to protecting western regal fritillary 
habitat because native plant diversity declines when nonnative plant 
species invade and become established in prairies (Boettcher et al. 
1993, p. 35). Spot spraying, hand pulling, or mechanical treatment of 
noxious weeds would be excepted from the take prohibitions and may 
occur at any time during the year. Incidental take that occurs as a 
result of mowing that is carried out for the purpose of controlling one 
or more noxious weed species will also be excepted.
    Broadcast application of herbicides, however, may result in 
significant deterioration of native plant diversity in prairies (Smart 
et al. 2011, p. 184). Therefore, we would not except incidental take of 
the western regal fritillary that may result from broadcast spraying of 
herbicides, which we define as the application of herbicides, often 
aerially or by vehicles, evenly, widely, and indiscriminately across 
the entire

[[Page 63906]]

application area, unless the application area is dominated by noxious 
weeds.

(4) Haying and Mowing

    Haying and mowing of native grasslands can improve western regal 
fritillary habitats by removing vegetation that outcompetes violets for 
light, nutrients, and water; stimulating the growth of native nectar 
sources; and improving the mosaic of diverse successional stages. 
Therefore, we will except incidental take associated with annual haying 
and mowing in western regal fritillary habitats.

(5) Prescribed Fire

    Prescribed fire is a key grassland management tool that can 
preserve native grassland habitat by controlling woody encroachment and 
introduced species and stimulating growth of native vegetation. When 
used with other grassland management techniques and best management 
practices, the periodic disturbance caused by prescribed fire helps 
maintain suitable regal fritillary habitat on the landscape. We 
acknowledge that fire is also a stressor to the western subspecies. 
Adverse effects to individuals may occur if burning occurs in occupied 
habitats, and local population-level impacts are possible if suitable 
occupied habitats are burned extensively without retaining refugia or 
if such sites are lacking adjacent proximal occupied habitats that 
could serve as recolonization sources. However, these effects can be 
controlled to maximize the benefits to the western regal fritillary. 
Therefore, we will except incidental take associated with prescribed 
fire if the following conditions are met to reduce adverse effects:
    (a) Prescribed fire burn units must be established to avoid burning 
the majority of suitable habitat at the landscape scale and to allow 
for refugia; and
    (b) The return interval for prescribed fire on a particular unit is 
3 to 5 years.

(6) Brush Control

    If allowed to become too dense, woody vegetation can crowd out 
native grassland habitat. Consequently, brush control would be excepted 
from the take prohibitions and may occur at any time during the year. 
Brush control methods may include mechanical means, burning, grazing, 
or spot use of herbicides if in compliance with the other excepted 
activities in the 4(d) rule. If mechanical means such as brush hogs are 
used, the blade must be set to 20 cm (8 in) or higher above the ground. 
If herbicides are used, an appropriate systemic herbicide to prevent 
regrowth must be directly applied to cut stems. Broadcast spraying in 
western regal fritillary habitat would not be excepted because it may 
remove all violet and nectar plants for the western subspecies.

(7) Mowing Section Line Rights-of-Way and Recreational Trails

    Section line rights-of-way and some recreational trails need to be 
mowed several times during the growing season to ensure that snow will 
not catch and block vehicle access and to ensure access and safety for 
hiking and other intended recreational activities, respectively. 
Section line rights-of-way typically have disturbed soil that has been 
contoured for a roadway and are likely to contain only small 
proportions of western regal fritillary habitat at any affected site. 
Recreational trails are travel ways established either through 
construction or use that are intended for and passable by at least one 
or more of the following: foot traffic, bicycles, in-line skates, 
wheelchairs, or cross-country skis. Such trails are typically narrower 
than roads. Therefore, impacts to western regal fritillary individuals 
and populations are likely to be minimal, and any incidental take that 
results from mowing section line rights-of-way and recreational trails 
will be excepted.

III. Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    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 each Federal action agency 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 designated 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 also 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. Rather, designation requires that, where a landowner 
requests Federal agency funding or authorization for an action that may 
affect an area designated as critical habitat, the Federal agency 
consult with the Service under section 7(a)(2) of the Act. If the 
action may affect the listed species itself (such as for occupied 
critical habitat), the Federal agency would have already been required 
to consult with the Service even absent the designation because of the 
requirement to ensure that the action is not likely to jeopardize the 
continued existence of the species. Even if the Service were to 
conclude after consultation that the proposed activity is likely to 
result in destruction or adverse modification of the critical habitat, 
the Federal action agency and the landowner are not required to abandon 
the proposed activity, or to restore or recover the species; instead, 
they must 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

[[Page 63907]]

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 data available, those physical or biological 
features that are essential to the conservation of the species (such as 
space, food, cover, and protected habitat).
    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.
    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) the prohibitions found in section 9 of the Act for the 
eastern subspecies or the 4(d) rule for the western subspecies. 
Federally funded or permitted projects affecting listed species outside 
their designated critical habitat areas may still result in jeopardy 
findings in some cases. These protections and conservation tools will 
continue to contribute to recovery of the 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 
available at the time of those planning efforts calls for a different 
outcome.

Critical Habitat Determinability

    We have determined that critical habitat is prudent, but not 
presently determinable, for both the eastern and western subspecies of 
regal fritillary. 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)).
    We have reviewed the available information pertaining to the 
biological needs of the regal fritillary and habitat characteristics 
where each subspecies is located. Careful assessments of the economic 
and environmental impacts that may occur due to a critical habitat 
designation are not yet complete, and we are working to acquire the 
complex information needed to perform those assessments. At this time, 
the information needed to perform the required analysis of the impacts 
of the designation is lacking for both subspecies. Therefore, we 
conclude that the designation of critical habitat for both the eastern 
and western subspecies of regal fritillary is not determinable at this 
time. The Act allows the Service an additional year to publish a 
critical habitat designation that is not determinable at the time of 
listing (16 U.S.C. 1533(b)(6)(C)(ii)).

Required Determinations

Clarity of the Rule

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

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

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

[[Page 63908]]

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), E.O. 13175 (Consultation and Coordination 
with Indian Tribal Governments), and the Department of the Interior's 
manual at 512 DM 2, we readily acknowledge our responsibility to 
communicate meaningfully with federally recognized Tribes on a 
government-to-government basis. In accordance with Secretaries' 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. The eastern subspecies does not occur on Tribal lands. For 
the western subspecies, we solicited information from the Tribes within 
the subspecies' range to inform the development of our SSA report, but 
we did not receive any responses. We will continue to coordinate with 
affected Tribes throughout the listing process, as appropriate.

References Cited

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

Authors

    The primary authors of this proposed rule are the staff members of 
the U.S. Fish and Wildlife Service's Species Assessment Team and the 
South Dakota and Pennsylvania Ecological Services Field Offices.

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

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

    Authority:  16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, 
unless otherwise noted.
0
2. In Sec.  17.11, in paragraph (h), amend the List of Endangered and 
Threatened Wildlife by adding entries for ``Fritillary, eastern regal'' 
and ``Fritillary, western regal'' in alphabetical order under INSECTS 
to read as follows:


Sec.  17.11   Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                          Listing citations and
           Common name              Scientific name      Where listed         Status         applicable rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
             Insects
 
                                                  * * * * * * *
Fritillary, eastern regal.......  Argynnis idalia     Wherever found....  E              [Federal Register
                                   idalia.                                                citation when
                                                                                          published as a final
                                                                                          rule].
Fritillary, western regal.......  Argynnis idalia     Wherever found....  T              [Federal Register
                                   occidentalis.                                          citation when
                                                                                          published as a final
                                                                                          rule]; 50 CFR
                                                                                          17.47(i).\4d\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------


0
3. Amend Sec.  17.47 by adding paragraph (i) to read as follows:


Sec.  17.47   Special rules--insects.

* * * * *
    (i) Western regal fritillary (Argynnis idalia occidentalis). (1) 
Prohibitions. The following prohibitions that apply to endangered 
wildlife also apply to the western regal fritillary. Except as provided 
under paragraph (i)(2) of this section and Sec. Sec.  17.4 and 17.5, it 
is unlawful for any person subject to the jurisdiction of the United 
States to commit, to attempt to commit, to solicit another to commit, 
or cause to be committed, any of the following acts in regard to this 
subspecies:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken specimens, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of commercial 
activity, as set forth at Sec.  17.21(e) for endangered wildlife.
    (v) Sale or offer for sale, as set forth at Sec.  17.21(f) for 
endangered wildlife.
    (2) Exceptions from prohibitions. In regard to this subspecies, you 
may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take, as set forth at Sec.  17.31(b).
    (iv) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.
    (v) Take incidental to an otherwise lawful activity caused by:
    (A) Routine livestock ranching activities on private, State, or 
Tribal lands, or any other lands not under Federal jurisdiction, 
including:
    (1) The construction and maintenance of fences to manage livestock 
and ranches;
    (2) The installation and maintenance of livestock gathering and 
management features, such as corrals, loading chutes, and other 
livestock working and ranching facilities; and
    (3) The development of new livestock watering sources and 
facilities and the maintenance of existing livestock watering 
facilities.
    (B) Livestock grazing on private, State, or Tribal lands, including 
light-to-moderate grazing intensities in the late fall and early 
spring, and patch burn grazing methods that may help maintain an 
annually shifting mosaic of fire and grazing across a landscape to 
increase the diversity and structure of vegetation.
    (C) Noxious weed control efforts, including spot spraying, hand 
pulling, and mechanical treatments (such as mowing) in all areas.

[[Page 63909]]

    (D) Haying and mowing in western regal fritillary habitats.
    (E) Prescribed fire that:
    (1) Incorporates established burn units to avoid burning a majority 
of the western regal fritillary habitat on the landscape and maintains 
refugia for the western regal fritillary; and
    (2) Operates on 3- to 5-year return intervals for the burn units.
    (F) Brush control of woody vegetation, that:
    (1) If conducted using mechanical methods, uses blades set at 20 
centimeters (8 inches) or more above the ground; and
    (2) If conducted using chemical treatments, uses appropriate, 
systemic herbicides to prevent regrowth applied directly to cut stems.
    (G) Mowing section line rights-of-way and recreation trails.

Gary Frazer,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2024-16982 Filed 8-5-24; 8:45 am]
BILLING CODE 4333-15-P