[Federal Register Volume 87, Number 86 (Wednesday, May 4, 2022)]
[Proposed Rules]
[Pages 26319-26337]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-09446]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R6-ES-2021-0134; FF09E21000 FXES1111090FEDR 223]
RIN 1018-BE98


Endangered and Threatened Wildlife and Plants; Threatened Species 
Status With Section 4(d) Rule for the Silverspot Butterfly

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 a subspecies of butterfly (Speyeria nokomis nokomis), a silverspot 
butterfly from Colorado, New Mexico, and Utah, as a threatened species 
under the Endangered Species Act of 1973, as amended (Act), with a rule 
issued under section 4(d) of the Act (``4(d) rule''). This document 
also serves as our 12-month finding on a petition to list the 
silverspot. After a review of the best available scientific and 
commercial information, we find that listing the subspecies is 
warranted. If we finalize this rule as proposed, it would add this 
subspecies to the List of Endangered and Threatened Wildlife and extend 
the Act's protections to the subspecies. We determined that designating 
critical habitat for this subspecies under the Act is not prudent.

DATES: We will accept comments received or postmarked on or before July 
5, 2022. 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 June 21, 2022.

ADDRESSES: 
    Written comments: You may submit comments by one of the following 
methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter the docket number or RIN 
for this rulemaking (presented above in the document headings). For 
best results, do not copy and paste either number; instead, type the 
docket number or RIN into the Search box using hyphens. Then, click on 
the Search button. On the resulting page, in the Search panel on the 
left side of the screen, under the Document Type heading, check the

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Proposed Rule box to locate this document. You may submit a comment by 
clicking on ``Comment.''
    (2) By hard copy: Submit by U.S. mail to: Public Comments 
Processing, Attn: FWS-R6-ES-2021-0134, 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: For this proposed rule, 
supporting materials are available at https://www.regulations.gov under 
Docket No. FWS-R6-ES-2021-0134, and at the Western Colorado Ecological 
Services Field Office (see FOR FURTHER INFORMATION CONTACT).

FOR FURTHER INFORMATION CONTACT: Ann Timberman, Western Colorado 
Supervisor, U.S. Fish and Wildlife Service, Western Colorado Ecological 
Services Field Office, 445 West Gunnison Avenue, Grand Junction, CO 
81501; telephone 970-628-7181. Individuals in the United States who are 
deaf, deafblind, hard of hearing, or have a speech disability may dial 
711 (TTY, TDD, or TeleBraille) to access telecommunications relay 
services. Individuals outside the United States should use the relay 
services offered within their country to make international calls to 
the point-of-contact in the United States.

SUPPLEMENTARY INFORMATION:

Executive Summary

    Why we need to publish a rule. Under the Act, a species warrants 
listing if it meets the definition of an endangered species (in danger 
of extinction throughout all or a significant portion of its range) or 
a threatened species (likely to become endangered in the foreseeable 
future throughout all or a significant portion of its range). We have 
determined that the silverspot butterfly (Speyeria nokomis nokomis) 
meets the definition of a threatened species; therefore, we are 
proposing to list it as such. We have determined that designation of 
critical habitat is not prudent. Both listing a species as an 
endangered or threatened species and designating critical habitat can 
be completed only by issuing a rule through the Administrative 
Procedure Act rulemaking process.
    What this document does. We propose to list the silverspot 
butterfly as a threatened species with a 4(d) rule.
    The basis for our action. Under the Act, we may determine that a 
species is an endangered or threatened species because of any of five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. We have determined that habitat loss and 
fragmentation, incompatible livestock grazing, human-caused hydrologic 
alteration, genetic isolation, and the effects of climate change 
negatively affect the silverspot butterfly's viability at a population 
level.
    Section 4(a)(3) of the Act requires the Secretary of the Interior 
(Secretary) to designate critical habitat concurrent with listing to 
the maximum extent prudent and determinable. 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 protections; 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. 
In the case of the silverspot butterfly, we found that designating 
critical habitat was not prudent, as explained later in this document.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other concerned governmental agencies, 
Native American Tribes, the scientific community, industry, or any 
other interested parties concerning this proposed rule.
    We particularly seek comments concerning:
    (1) The subspecies' biology, range, and population trends, 
including:
    (a) Biological or ecological requirements of the subspecies, 
including habitat requirements for feeding, breeding, and sheltering;
    (b) Genetics and taxonomy;
    (c) Historical and current range, including distribution patterns;
    (d) Historical and current population levels, and current and 
projected trends; and
    (e) Past and ongoing conservation measures for the subspecies, its 
habitat, or both.
    (2) Factors that may affect 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.
    (3) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to this subspecies and existing 
regulations that may be addressing those threats.
    (4) Additional information concerning the historical and current 
status, range, distribution, and population size of this subspecies, 
including the locations of any additional populations of this 
subspecies.
    (5) Information on regulations that are necessary and advisable to 
provide for the conservation of the silverspot butterfly and that the 
Service can consider in developing a 4(d) rule for the subspecies. In 
particular, information concerning the extent to which we should 
include any of the Act's section 9 prohibitions in the 4(d) rule or 
whether we should consider any additional exceptions from the 
prohibitions in the 4(d) rule.
    (6) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act (16 U.S.C. 1531 et 
seq.), including information to inform the following factors that the 
regulations identify as reasons why designation of critical habitat may 
be not prudent:
    (a) The species is threatened by taking or other human activity and 
identification of critical habitat can be expected to increase the 
degree of such threat to the species;
    (b) The present or threatened destruction, modification, or 
curtailment of a species' habitat or range is not a threat to the 
species, or threats to the species' habitat stem solely from causes 
that cannot be addressed through management actions resulting from 
consultations under section 7(a)(2) of the Act;
    (c) Areas within the jurisdiction of the United States provide no 
more than negligible conservation value, if any, for

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a species occurring primarily outside the jurisdiction of the United 
States; or
    (d) No areas meet the definition of critical habitat.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for, or 
opposition to, the action under consideration without providing 
supporting information, although noted, will not be considered in 
making a determination, as section 4(b)(1)(A) of the Act directs that 
determinations as to whether any species is an endangered or 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.
    Because we will consider all comments and information we receive 
during the comment period, our final determinations may differ from 
this proposal. Based on the new information we receive (and any 
comments on that new information), we may conclude that the subspecies 
is endangered instead of threatened, or we may conclude that the 
subspecies does not warrant listing as either an endangered species or 
a threatened species. For critical habitat, we may conclude that 
designation of critical habitat is indeed prudent. In addition, we may 
change the parameters of the prohibitions or the exceptions to those 
prohibitions in the 4(d) rule if we conclude it is appropriate in light 
of comments and new information received. For example, we may expand 
the prohibitions to include prohibiting additional activities if we 
conclude that those additional activities are not compatible with 
conservation of the subspecies. 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 subspecies.

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. For the immediate future, we will provide these public 
hearings using webinars that will be announced on the Service's 
website, in addition to the Federal Register. The use of these virtual 
public hearings is consistent with our regulations at 50 CFR 
424.16(c)(3).

Previous Federal Actions

    On July 3, 1978, we proposed to list Speyeria nokomis nokomis (with 
the common name ``Great Basin silverspot butterfly'') as a threatened 
species with critical habitat under the Act (43 FR 28938). Due to a new 
range delineation (described in Background below), the former common 
name, Great Basin silverspot butterfly, is no longer valid as the 
subspecies is not found within the Great Basin; therefore, we will 
refer to the S. n. nokomis subspecies as ``silverspot'' in this 
proposed rule. On March 6, 1979, we withdrew the July 3, 1978, proposed 
rule, along with certain other proposed rules, because they did not 
meet requirements set forth in the Endangered Species Act Amendments of 
1978 (Pub. L. 95-632, 92 Stat. 3751); see 44 FR 12382.
    On May 22, 1984, we identified the silverspot as a category 2 
candidate species (49 FR 21664). Category 2 candidate species comprised 
taxa for which information in the Service's possession indicated that a 
proposal to list the species as endangered or threatened was possibly 
appropriate, but for which conclusive data on biological vulnerability 
and threat(s) were not currently available to support proposed rules at 
that time. Later candidate notices of review (CNOR) retained the 
subspecies as a category 2 candidate species (54 FR 554, January 6, 
1989; 56 FR 58804, November 21, 1991; 59 FR 58982, November 15, 1994).
    On February 28, 1996, we discontinued the designation of category 2 
species as candidates in CNORs (61 FR 7596), and on December 5, 1996, 
we published a notice of final decision (61 FR 64481) to discontinue 
the practice of maintaining a list of species regarded as ``category 2 
candidates.'' These actions resulted in the removal of the silverspot 
from the candidate list.
    In 2013, WildEarth Guardians petitioned us to list the silverspot. 
On January 12, 2016, we published a 90-day finding (81 FR 1368) stating 
that the petition presented substantial scientific or commercial 
information indicating that the petitioned action may be warranted and 
announcing our intent to proceed with a status review. In 2021, we 
completed a species status assessment report for the silverspot 
(hereafter, SSA report) to compile the best scientific and commercial 
data available regarding the subspecies' biology and factors that 
influence the subspecies' viability (Service 2021, entire).

Supporting Documents

    A species status assessment (SSA) team prepared an SSA report for 
the silverspot butterfly (Service 2021, entire). The SSA team was 
composed of Service biologists, in consultation with other species 
experts. The SSA report represents a compilation of the best scientific 
and commercial data available concerning the status of the 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 of listing actions 
under the Act, we sought the expert opinions of four appropriate 
specialists regarding the SSA report. We received four responses. We 
also sent the SSA report to partners, including scientists with 
expertise in the subspecies, its habitat, and genetics, for review. The 
SSA report provides the scientific basis for this proposed listing 
rule.

I. Proposed Listing Determination

Background

    A thorough review of the taxonomy, life history, and ecology of the 
silverspot butterfly (hereafter, silverspot) is presented in the SSA 
report (Service 2021, pp. 4-24), and is briefly summarized here.
    The silverspot is a relatively large butterfly with up to a 3-inch 
wingspan. Males typically have bright orange on

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the upper side of the wing, while females typically have cream or light 
yellow with brown or black. The underside of the wing of both sexes has 
silvery-white spots, giving the subspecies' the common name of 
silverspot butterfly.
    Based on recent genetic analysis, there are five silverspot 
butterfly subspecies including 10 major populations of S. nokomis 
throughout the United States and Mexico (Cong et al. 2019, entire). We 
established a new, more accurate range boundary for S. n. nokomis in 
this SSA based on the genetic analysis, which limits the distribution 
to east-central Utah through western and south-central Colorado and 
into north-central New Mexico (Service 2021, p. ii). The new range 
delineation shows that the subspecies does not occur in the Great Basin 
and thus the former common name, Great Basin silverspot butterfly, is 
no longer valid. We refer to the S. n. nokomis subspecies as 
``silverspot'' in this proposed rule.
    In the SSA report, we identified 10 populations of silverspot in 
our analysis, including the following: Archuleta, Conejos, Costilla, 
Garfield, La Plata, Mesa/Grand, Montrose/San Juan, and Ouray 
populations in Colorado and Utah; and the San Miguel/Mora and Taos 
populations in New Mexico (Service 2021, figure 14 and table 4). 
Populations of silverspot are known to occur between 5,200 feet (ft) 
(1,585 meters (m)) and 8,300 ft (2,530 m). The butterfly requires moist 
habitats in mostly open meadows with a variety of herbaceous and woody 
vegetation. Eggs are laid on or near the bog violet (Viola 
nephrophylla/V. sororia var. affinis), which the larvae feed on 
exclusively. A variety of flowering plants provide adult nectar 
sources. The butterfly completes its entire life cycle in one year.

Regulatory and Analytical Framework

Regulatory Framework

    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR part 424) set forth the procedures for determining 
whether a species is an endangered species or a threatened species. The 
Act defines an ``endangered species'' as a species that is in danger of 
extinction throughout all or a significant portion of its range, and a 
``threatened species'' as a species that is likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range. The Act 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 expected response by the species, 
and the effects of the threats--in light of those actions and 
conditions that will ameliorate the threats--on an individual, 
population, and species level. We evaluate each threat and its expected 
effects on the species, then analyze the cumulative effect of all of 
the threats on the species as a whole. We also consider the cumulative 
effect of the threats in light of those actions and conditions that 
will have positive effects on the species, such as any existing 
regulatory mechanisms or conservation efforts. The Secretary determines 
whether the species meets the Act's definition of an ``endangered 
species'' or a ``threatened species'' only after conducting this 
cumulative analysis and describing the expected effect on the species 
now and in the foreseeable future.
    The Act does not define the term ``foreseeable future,'' which 
appears in the statutory definition of ``threatened species.'' Our 
implementing regulations at 50 CFR 424.11(d) set forth a framework for 
evaluating the foreseeable future on a case-by-case basis. The term 
``foreseeable future'' extends only so far into the future as the 
Service can reasonably determine that both the future threats and the 
species' responses to those threats are likely. In other words, the 
foreseeable future is the period of time in which we can make reliable 
predictions. ``Reliable'' does not mean ``certain''; it means 
sufficient to provide a reasonable degree of confidence in the 
prediction. Thus, a prediction is reliable if it is reasonable to 
depend on it when making decisions.
    It is not always possible or necessary to define foreseeable future 
as a particular number of years. Analysis of the foreseeable future 
uses the best scientific and commercial data available and should 
consider the timeframes applicable to the relevant threats and to the 
species' likely responses to those threats in view of its life-history 
characteristics. Data that are typically relevant to assessing the 
species' biological response include species-specific factors such as 
lifespan, reproductive rates or productivity, certain behaviors, and 
other demographic factors.

Analytical Framework

    The SSA report documents the results of our comprehensive 
biological review of the best scientific and commercial data regarding 
the status of the species, including an assessment of the potential 
threats to the species. The SSA report does not represent a decision by 
the Service 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. 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-2021-0134 on https://www.regulations.gov.
    To assess the silverspot's viability, we used the three 
conservation biology principles of resiliency, redundancy, and 
representation (Shaffer and Stein 2000, pp. 306-310). Briefly, 
resiliency supports the ability of the species to withstand 
environmental and demographic stochasticity (for example, wet or dry, 
warm or cold years), redundancy supports the ability of the species to 
withstand catastrophic events

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(for example, droughts, large pollution events), and representation 
supports the ability of the species to adapt over time to long-term 
changes in the environment (for example, climate changes). In general, 
the more resilient and redundant a species is and the more 
representation it has, the more likely it is to sustain populations 
over time, even under changing environmental conditions. Using these 
principles, we identified the silverspot's 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 individual subspecies' life-
history needs. The next stage involved an assessment of the historical 
and current condition of the subspecies' demographics and habitat 
characteristics, including an explanation of how the subspecies arrived 
at its current condition. The final stage of the SSA involved making 
predictions about the subspecies' responses to positive and negative 
environmental and anthropogenic influences. Throughout all of these 
stages, we used the best available information to characterize 
viability as the ability of a species (or in this case, subspecies, 
which is a listable entity under the Act) to sustain populations in the 
wild over time. We use this information to inform our regulatory 
decision.

Summary of Biological Status and Threats

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

Species Needs

Individual Needs
    Individual silverspot needs include wet meadows supported by 
springs, seeps, streams, or irrigated areas that contain the bog violet 
host plant for eggs and larvae and other herbaceous vegetation for 
cover and food resources. The butterflies may benefit from a light 
interspersion of willow or other shrubs for shade and for larval 
shelter. More dense willow and shrubs often surround open meadows where 
silverspots occur and, as long as the woody vegetation does not take 
over the meadows, the margins of denser stands can be beneficial for 
shade and shelter as well.
Population Needs
    Populations need abundant individuals within habitat patches of 
adequate size and quality to maintain survival and reproduction. In 
general, the greater the suitable habitat acreage, and the greater the 
number of individuals within a population, the greater the resilience. 
Furthermore, colonies and populations need to be close enough to each 
other for individuals to breed with each other in order to maintain 
genetic diversity. Silverspots likely do not fly more than 5-10 miles 
(mi) (8-16 kilometers (km)) and would likely have difficulty finding 
another colony beyond this distance (Ellis 2020a, 2020b, 2020c, pers. 
comm.). Additionally, silverspots need the bog violet to be of 
sufficient extent and density to support colonies and populations. We 
define colonies to mean areas of abundant violets that produce 
butterflies, as well as surrounding habitat with nectar sources. If 
there is narrow but contiguous nectaring habitat up or down a drainage 
but without violets (or with only sparse violets), we consider those 
areas transitional corridors that are likely valuable for dispersal and 
genetic connectivity.
    The silverspot and other S. nokomis subspecies can move between 
colonies within a continuous or nearly continuous riparian zone (Arnold 
1989, pp. 10, 14; Fleishman et al. 2002, p. 708). For example, six 
colonies occurred along a 5-mi stretch in Unaweep Canyon that had 
likely genetic interchange (Ellis 1989, p. 3). However, these are 
considered separate colonies due to the natural or human-caused 
patchiness of bog violets up and down the canyon. In a mark-recapture 
study (Arnold 1989, pp. 10, 14, 21) in Unaweep Canyon, about 50 percent 
of the recaptured butterflies moved between two colonies separated by 
about 0.75 mi (1.2 km). Based on this work, it was speculated that 
silverspots could easily move at least 1 mile, and, based on this, 
Ellis (1989, p. 19) further speculated that there was exchange of 
individuals among all the Unaweep Canyon colonies every 1 to 5 years. 
This information also provided the basis for Ellis' professional 
judgement that colonies or populations farther than 5 to 10 mi (8 to 16 
km) from each other are likely isolated (Ellis 2020a, 2020b, 2020c, 
pers. comm.).
    Some silverspot populations have single colonies, while others have 
more than one colony, creating a metapopulation. A metapopulation 
structure is where individuals in colonies are close enough to 
interbreed and can recolonize temporarily extirpated colonies. Colonies 
in a functioning metapopulation can be recolonized if local naturally 
occurring (stochastic) events cause extirpation of a colony. For 
instance, a flood may extirpate a colony, but if there is a nearby 
source for the bog violet and associated plant species, the area may 
return to suitable habitat condition and be recolonized by the 
butterfly.
    Unfortunately, there is very little information on what an 
adequate-sized habitat patch for silverspot is, especially if there is 
only a single colony in a population. A professional estimate for 
minimum patch size of colonies is 2 acres (ac) (0.8 hectares (ha)) if 
the habitat has a reliable groundwater source and has high violet 
density; 5 ac (2 ha) if violets are less dense due to natural or human-
caused variability within a patch (Ellis 2020c, pers. comm.). Although 
it is possible a single 2-acre or 5-acre patch of habitat could support 
the butterfly for a period of time, a more resilient population will 
likely contain at least three colonies of those sizes or greater. A 
three-colony metapopulation will have a better chance of survival by 
spreading the risk of extirpation if a natural event occurs at one or 
two of the colonies. Thus, the remaining one or two colonies can 
recolonize the extirpated sites assuming suitable habitat remains or 
reestablishes. Due to natural variability in soil and topographic 
conditions, we assume that most areas within the silverspot's range are 
likely to have a lower density of violets, rather than dense violets 
(Service 2021, p. 21). Consequently, under this assumption, a minimum 
amount of habitat for a sufficiently resilient population may be 12 ac 
(5 ha) and this can be made up of multiple colonies as long as they are 
at least 2 ac (0.8 ha) in size (Service 2021, p. 21). Due to its 
isolation, a single-colony population likely needs to have hundreds of 
acres of habitat in order to ensure there are enough butterflies to 
maintain genetic diversity and viability over the long term (Service 
2021, p. 21). The specific minimum threshold for single colonies to 
maintain viability is unknown, but the larger the acreage is, the 
greater the resiliency and higher likelihood of viability.
    There is also little information on the minimum number of 
silverspot individuals needed to sustain a colony. There have only been 
two demographic studies for silverspot that occurred at the same 
locations 10 years apart: 1979 and 1989 (Arnold 1989). The 1989 study 
found a daily estimate of between 48 and 260 butterflies with two 
different models at the Unaweep Seep colony

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(Arnold 1989, pp. 6, 14). A combined population estimate at the Unaweep 
Seep colony and another upstream colony in Unaweep Canyon (which is 
considered two colonies due to intervening transitional habitat) 
resulted in a range of daily abundance from 594 to 2,689 butterflies. 
Quality of habitat may have as much weight in determining resiliency of 
a colony or population as does overall size of a habitat patch or 
number of individuals. Habitat quality could potentially be measured by 
density of violets. The Unaweep Seep study (Arnold 1989, p. 20) 
revealed that the larger colony with many individuals became 
extirpated, likely due to vegetative encroachment, while the upstream 
colony with more violets remained extant. Consequently, populations 
appear to have greater chance for survival when containing more 
violets.
    Based on observation of grazed and burned properties in Unaweep 
Canyon, it was determined that occasional or well-managed grazing and 
burning likely benefit the violet by reducing willows, as well as 
reducing thatch buildup from grasses and sedges (Arnold 1989, p. 14; 
Ellis 1989, pp. 18, 19). Consequently, natural factors or management 
activities that lead to early seral stages or at least more open 
conditions where willow, grass, sedge or other vegetation does not 
outcompete violets is important to colonies and populations.
    Single-colony populations likely need to have a very large habitat 
area, in the hundreds of acres, but might still need occasional 
immigration from other populations to maintain genetic diversity and 
resiliency for long-term persistence. Based on the scant evidence, the 
minimum number of individuals that are needed to sustain a silverspot 
colony or population is unknown, and even apparent natural but 
detrimental habitat factors, such as excessive growth of other plants, 
can cause extirpation of seemingly large colonies. Without additional 
study, it is not known what the minimum habitat size is to maintain 
viability, nor what density or abundance of bog violets or nectar 
sources is needed to sustain a colony or population, nor the maximum 
distance between colonies or populations that can be reached for 
genetic interchange to still be able to occur on a regular basis. 
Furthermore, it is unknown if very large single-colony populations can 
be sufficiently resilient without occasional genetic interchange from 
other populations.
    In summary, to be adequately resilient, silverspot populations need 
water to sustain violets for the larvae, as well as occasional or 
seasonal disturbance by grazing from native ungulates or domestic 
livestock, or burning, mowing, or non-catastrophic flooding, to 
occasionally remove vegetation that might otherwise crowd out the 
violets and other nectar plants for the adults. Furthermore, based on 
expert opinion and evidence from Arnold (1989) and Ellis (1989), the 
most resilient populations need to be at least 2 ac (0.8 ha) in size 
with dense violets or at least 5 ac (2 ha) in size with less dense 
violets, and need to have a few to several colonies within 0.75 to 5 mi 
(1.2 to 8 km) of each other and likely be not more than 10 mi (16 km) 
from each other (Ellis 2020c, pers. comm.).
Species Needs
    To maintain viability, silverspots need to have a sufficient 
quality and quantity of habitat for adequately resilient populations, 
numerous populations to create redundancy in the event of catastrophic 
events, and broad enough genetic and ecological diversity to adapt to 
changing environmental conditions (representation). The subspecies will 
have a better chance of long-term viability if single-colony 
populations and even the metapopulations occasionally receive 
individuals from other populations such that genetic interchange occurs 
and they are able to adapt more readily to environmental changes.

Factors Influencing Subspecies Viability

    We reviewed the potential risk factors (i.e., threats, stressors) 
that could be affecting the silverspot now and in the future. In this 
proposed rule, we will discuss only those factors in detail that could 
meaningfully impact the status of the subspecies. Habitat loss and 
fragmentation, human-caused hydrologic alteration, livestock grazing, 
genetic isolation, exotic plant invasion, climate change, climate 
events, larval desiccation, and collecting are all factors that 
influence or could influence the subspecies' viability. Those risks 
that are not known to have effects on silverspot populations, such as 
disease, predation, prescribed burning or wildfire, and pesticides, are 
not discussed here but are evaluated in the SSA report.
Habitat Loss and Fragmentation
    Habitat loss from golf course and housing development caused 
extirpation of two historical colonies north of Durango, Colorado 
(Ellis and Fisher 2020, pers. comm.). The remaining known site in the 
La Plata population has residential and commercial development across 
the street from it, and one of two drainages supplying it water has 
relatively new housing and golf courses all around within 1.5 air miles 
(2.4 km), potentially degrading downstream silverspot habitat through 
hydrologic alteration. Housing development also appears to have been a 
contributing factor in extirpation of the Beulah, New Mexico, colony 
(Scott and Fisher 2014, p. 3). In Colorado, it is possible that Rifle 
Gap Reservoir and Dam degraded and fragmented habitat, as one butterfly 
was sighted at a small wetland downstream of the dam and the reservoir 
flooded and fragmented habitat upstream. Additional habitat alteration 
upstream and downstream from a variety of factors also has likely 
fragmented habitat. Many other colonies/populations have development 
around them that also either directly encroaches on the habitat or 
likely has caused degradation and fragmentation from homes, roads, 
hydrologic alteration and habitat conversion.
    Agricultural habitat conversion can cause loss or fragmentation of 
habitat and typically involves mowing native meadows or growing exotic 
grasses for hay. Although it is unknown if all agricultural conversion 
has caused habitat to become unsuitable, aerial imagery reveals that 
agricultural conversion has been extensive within the silverspot's 
range. It has likely caused loss of unknown colonies over the last 150 
years and has fragmented native habitat, reducing connectivity between 
colonies and populations. Annual haying may be less detrimental than 
haying two or three times a summer. A related subspecies in Arizona and 
New Mexico persisted for many years (Cong et al. 2019) even though 
haying occurs there once a year typically in late August or September 
(Smith 2019, pers. comm.).
    Despite potential compatibility with annually mowing native hay 
fields, agricultural conversion to unsuitable crops or fragmentation of 
habitat has been extensive. Furthermore, residential and commercial 
development, and other development like roads, continues to limit and/
or degrade habitat in or adjacent to existing colonies/populations. 
Habitat loss and fragmentation, therefore, has meaningfully reduced the 
viability of the subspecies.
Hydrologic Alteration
    Hydrologic alteration is also a factor influencing the subspecies' 
viability. Hydrologic alteration can result from a variety of sources, 
including, but not limited to, diversions for agricultural and domestic 
use, erosion and stream

[[Page 26325]]

channel incision caused by livestock grazing, mining, roads, dredging 
and filling of wetlands, removal of beaver dams, and creation and 
operation of large human-made dams. For example, the only known colony 
in the Costilla population has a diversion ditch delimiting its south 
side that may have reduced the size of colony, and that ditch and other 
diversions have allowed for extensive agricultural development in the 
drainage that has altered native habitat and likely dropped the water 
table in much of the area. The Paradox colony in the Montrose/San Juan 
population also has had livestock grazing and water diversions occur 
over the last 30 years, which have degraded the quality of the wet 
meadow areas and lowered the water table (Ellis and Ireland 2018, pers. 
observation).
    Many drainages in the Sacramento Mountains, where the Mescalero 
silverspot colony may have occurred (see SSA report), succumbed to 
incision of streams around 1900, in turn lowering water tables and 
eliminating wet meadow habitat (Cary 2020b, pers. comm.). Incision of 
stream channels occurred due to erosion from deforestation, conversion 
to agricultural and grazing lands, mining, etc. (Cary 2020b, 2020c, 
pers. comm.). Beavers were also eliminated around 1900 in the 
Sacramento Mountains (and other parts of the West), which also 
undoubtedly caused reduction of water tables and elimination of wet 
meadow habitat suitable for the silverspot and other wetland-dependent 
species (Cary 2020b, 2020c, pers. comm.). Hydrologic alteration that 
degrades riparian areas and lowers water tables from natural systems 
has occurred not only in the Costilla population, Montrose/San Juan 
population, and Sacramento Mountains, but extensively in the western 
United States, including much of the silverspot's range. Hydrologic 
alteration continues to limit suitable habitat and is a major factor 
influencing the viability of the subspecies.
Livestock Grazing
    Livestock grazing may cause habitat loss and degradation if 
excessive, especially in the naturally scarce habitats of the 
silverspot (Hammond and McCorkle 1983, p. 219) and depending on the 
timing and intensity. Year-round grazing or heavy summer grazing is 
typically incompatible with silverspots because livestock graze on the 
violet leaves, nectar sources, and other vegetation necessary for the 
butterfly when the larvae and adults need them (Ellis 1999, p. 5). For 
example, an area adjacent to a known site in the Ouray population has 
underlying hydrology and soils beneficial for silverspots, but the 
habitat is unsuitable due primarily to grazing and perhaps to a lesser 
extent occasional mowing for hay (Service 2021, figure 19). Light or 
moderate summer grazing (up to 20 or 30 percent vegetative utilization) 
may be acceptable, but total rest from grazing in the summer is 
preferred (Arnold 1989, p. 14; Ellis 2020d, pers. comm.).
    If one or more kinds of vegetation are too dense, they can prevent 
the bog violet from persisting and thus cause extirpation of the 
butterfly. This occurred in the Unaweep Seep colony in the Mesa/Grand 
population, perhaps primarily as a result of spike rush (Eleocharis 
spp.) invasion of meadows but also seemingly because of grass, sedge, 
and willow invasion (Arnold 1989, pp. 9, 14; Ellis 1999, pp. 3, 5, 6). 
It is unknown if this invasion would have occurred without grazing or 
if long-term grazing was the factor that shifted vegetation. Without 
occasional reduction or removal, herbaceous or woody vegetation could 
crowd out violets. Grazing is ongoing in suitable habitat for the 
subspecies and can limit availability of habitat throughout the range. 
Although it can be compatible, grazing is expected to continue to be a 
major factor influencing the subspecies' viability.
Genetic Isolation
    Isolation can cause detrimental genetic and demographic effects and 
is a concern for the silverspot's population resiliency as well as 
redundancy and representation. Genetic isolation within the populations 
of silverspot analyzed in the SSA report does not currently appear to 
be an issue but may be in the future, especially if some populations 
become extirpated, leaving remaining populations even more isolated 
than in the current condition (Grishin 2020a, pers. comm.). Lower 
levels of genetic diversity can reduce the capacity of a population to 
respond to environmental change (i.e., representation) and may lead to 
reduced population fitness, such as longevity and fecundity (Darvill et 
al. 2006, p. 608). Another silverspot subspecies, S. n. apacheana, has 
low genetic diversity, likely from genetic drift (disappearance of 
genes as individuals die), as a result of genetic isolation and small 
population sizes (Britten et al. 1994). Genetic exchange between and 
within populations can alleviate problems with genetic drift and 
augment populations demographically. In S. n. apacheana, routine 
dispersal distances up to 2.5 mi (3.9 km) were documented, and 26 
percent of the recaptured butterflies had emigrated from the initial 
patch of capture (Fleishman et al. 2002, p. 708). This migration 
appears to play an important role for S. n. apacheana populations both 
demographically and genetically (Britten et al. 2003, p. 232). 
Consequently, the ability or inability of individuals to migrate 
between colonies and populations is expected to also be of benefit or 
detriment, respectively, for silverspot.
    Genetic isolation among populations of silverspot suggests reduced 
population fitness from genetic drift or for other reasons could be of 
concern in the future (Cong et al. 2019). All known silverspot 
populations are at least 24.5 mi (39 km) from each other and are 
genetically isolated from each other (Cong et al. 2019). Genetic 
analysis recently revealed that the Grand County colony is genetically 
similar to the Mesa County colonies and, hence, are part of the same 
population. Until recently (20-30 years ago), when Unaweep Seep was 
extant, the Grand County colony and Unaweep Seep colony in Mesa County 
were just under 20 mi (32 km) apart. Because alleles within genes can 
remain in the genome for hundreds or thousands of years, 20-30 years is 
a short time frame for separation of genetically similar colonies. 
Therefore, based on the latest scientific evidence (Cong et al. 2019), 
populations that are at least 20 miles apart are assumed to be separate 
populations. Currently, the distance between the two closest 
populations, which we know are genetically different and represent 
separate populations, is 24.5 air miles (39 km) (between the Taos and 
San Miguel/Mora populations in New Mexico). Consequently, and more 
specifically, the distance where populations of silverspot may not 
interbreed and thus may not support each other genetically or 
demographically appears to be somewhere between 20 and 24.5 air miles 
(32 and 39 km). The minimum distance of 20 mi (32 km), based on 
findings of Cong et al. (2019), was used in our analysis of genetic 
connectivity (see Current Condition, below).
    Reasons for isolation, specifically whether from natural 
fragmentation or human habitat alteration, are not currently known for 
all colonies. It is also not known how long single colonies may have 
been isolated from each other. Like the large Taos colony of 
silverspot, if an isolated colony has enough area of habitat to support 
a large population, it may be resilient enough to survive without 
nearby colonies and thus maintain viability for a long time. However, 
many of the silverspot populations, whether single-colony or

[[Page 26326]]

multi-colony metapopulations, have limited amounts of habitat. It is 
unknown specifically how long it will take for low genetic diversity to 
become a threat to the silverspot, but isolation of populations 
indicates that loss of genetic diversity could be a threat at some 
point, if loss of populations through lack of demographic support does 
not occur first, and both are cause for concern for the subspecies' 
viability.
Exotic Plant Invasion
    The Taos population has experienced some invasion by the exotic 
Siberian elm (Ulmus pumila). Because Siberian elm is widespread in the 
butterfly's range, we expect Siberian elm to increase if changes in 
climate reduce snowpack and water levels in the wet meadows of the Taos 
population (Cary 2020a, pers. comm.) or other populations. Similarly, 
the extirpated Unaweep Seep colony location was invaded by other exotic 
species, including Himalayan blackberry (Rubus armeniacus) and tree-of-
heaven (Ailanthus altissima). Although not known to occupy other 
colonies at present, these plant species could invade other colonies 
(Plank 2020, pers. comm.). Other exotic woody or herbaceous species 
(such as Russian olive (Elaeagnus angustifolia), tamarisk (Tamarix 
spp.), or leafy spurge (Euphorbia esula)) can rapidly take over habitat 
and could eliminate bog violets and other native plants. However, there 
is currently little to no data on plants at the colonies (Ellis 1989, 
pp. 14-15).
    Some nonnative thistles, such as Canada thistles (Cirsium arvense), 
occur in or around colonies and can create monocultures that create 
poor overall habitat conditions for the silverspot and bog violet by 
replacing native species (Ellis 1989, p. 14; Selby 2007, p. 30). Land 
managers in the West sometimes control the spread of exotic thistles, 
but Canada thistles (as well as native thistle) provide a nectar source 
for silverspots. Additionally, the adventive (exotic but not well-
established) bull thistle (C. vulgare) and burdock (Arctium minus) can 
provide nectar sources (Ellis 1989, p. 14). Because silverspots use 
exotic thistles, aggressive control of them has been advised against 
(Fisher 2020b, pers. comm.). It does not appear that monocultures of 
Canada thistle or other exotic vegetation have replaced native 
vegetation beneficial for the butterfly at observed colonies (Ellis and 
Ireland 2018, pers. observation), but study of plant composition at all 
of the colonies is needed to determine levels of exotic plant presence. 
Exotic plant invasion is currently considered a minor factor because 
exotic species are not currently known to be significantly influencing 
the subspecies' viability.
Climate Events
    Climate events are defined in the SSA as events that would happen 
within the range of normal variability (i.e., stochastic events). 
However, they may still cause reduction of habitat and number of 
butterflies. A record of other Speyeria in Utah indicates that too much 
rain can reduce numbers of butterflies but may be beneficial to 
violets, which can support greater numbers of butterflies the following 
year(s) (Myrup 2020b, pers. comm.). Similarly, floods may at least 
temporarily reduce habitat and vegetation as well as butterfly numbers. 
For instance, the Lake Fork River in northeast Utah flooded in spring 
2019, limiting or causing extirpation of related silverspot butterflies 
at a known colony in the Uinta Mountains (Ellis et al. 2019, pers. 
observation) that had been there the year before (Myrup 2019, pers. 
comm.). However, the flood event was not outside the norm for past 
observed flood events in that drainage. This stochastic event provides 
an example of normal climate events that can cause reduction in numbers 
of individual butterflies or temporary extirpation of a colony but are 
not expected to cause permanent reduction or extirpation. Thus, climate 
events are not expected to reduce the subspecies' viability in the long 
term and are considered as a minor factor influencing the subspecies' 
viability.
Climate Change
    The climate within the silverspot's range already appears to be 
changing as a result of increased greenhouse gas emissions, with 
earlier springs and warmer temperatures. Average temperatures in 
Colorado increased in the 30 years prior to 2014 by 2 degrees 
Fahrenheit ([deg]F) (1.1 degrees Celsius ([deg]C)), and by 2.5 [deg]F 
(1.4 [deg]C) in the last 50 years (Lukas et al. 2014, p. 2). Snowpack, 
as measured by snow water equivalent, has mostly been below average in 
Colorado since 2000. The timing of snowmelt and peak runoff has also 
shifted 1 to 4 weeks earlier in the last 30 years in Colorado. 
Furthermore, the Palmer Drought Severity Index has shown an increasing 
trend in soil-moisture drought conditions due to below average 
precipitation since 2000 and the warming trend (Lukas et al. 2014, p. 
2). More recent analysis using National Oceanic and Atmospheric 
Administration (NOAA) temperature data shows that, since 1895, the 
average temperature in much of the northern half of the silverspot's 
range has increased by, or more than, 3.6 [deg]F (2 [deg]C), and it is 
reported that average annual flows in the Colorado River Basin have 
declined by 20 percent over the past century (Eilperin 2020, entire). 
However, tree ring and other paleoclimate data indicate that there were 
more severe and sustained droughts prior to recent climate data (since 
1900) (Lukas et al. 2014, pp. 2, 3). The butterfly has survived through 
the more severe past droughts and, despite noted changes in climate 
over the last 36 years, climate has thus far not been a detectable 
factor in reduction of the subspecies' viability. Consequently, at the 
present and for the current condition analysis in the SSA report, 
climate change is considered a minor factor. However, climate appears 
to be at the verge of becoming a major factor; see additional 
discussion of climate change under Future Condition, below.
Desiccation of Larvae
    Desiccation of overwintering larvae may be a stressor if soil 
moisture and air humidity is too low or if larvae cannot remain 
hydrated. It is suspected that soil moisture and dead vegetation, along 
with some air flow, provide suitable conditions that prevent 
desiccation (Fisher 2020c, pers. comm.). Hydration also appears to be 
needed prior to first instar larvae overwintering and is achievable if 
water for drinking is freely available and if soil or air moisture is 
sufficient for absorption (Myrup 2020a, pers. comm.; Stout 2020, 
unpaginated). Snow cover may also provide some desiccation prevention 
and thermal cover, although it may not be a significant factor (Ellis 
2020e, pers. comm.). Snow cover may be of benefit during extreme cold 
(Fisher 2020a, pers. comm.). In general, however, extreme cold in the 
silverspot's range is preceded by snow; thus, extreme cold may kill 
some larvae but is likely not a major factor that reduces the 
subspecies' viability.
Collecting
    Collecting has occurred in silverspot colonies, and it is possible 
collecting in small colonies could negatively affect population 
resiliency (Ellis 1989, p. 15; Selby 2007, p. 31). We know of one 
example of a potential colony extirpation related to over-collection 
(Scott 2020, pers. comm.). However, collecting is not currently thought 
to be a significant stressor for silverspot since most colonies occur 
on private land, colony locations are largely unknown to the public, 
and current collecting pressure is not thought to be extensive (Ellis 
2020f, pers. comm.). In terms of effect on the current condition of the

[[Page 26327]]

subspecies, collecting is currently considered a minor factor, and 
efforts should be taken to keep it a minor factor in the future. There 
is concern with collecting if public land, or even private land, colony 
locations are revealed in the future, but currently this factor does 
not appear to be significantly reducing the subspecies' viability. 
However, losing even one of the remaining populations to collection 
could have a substantial impact on the subspecies' redundancy and 
representation. We are concerned with the potentially detrimental 
effects to the subspecies from future collection if silverspot 
locations, especially smaller populations, are made public, which would 
facilitate increased collection and potentially cause collection to 
become a major factor affecting the subspecies' viability (see III. 
Critical Habitat, below).
Cumulative Effects
    By using the SSA framework to guide our analysis of the scientific 
information documented in the SSA report, we have not only analyzed 
individual effects of factors on the subspecies, but we have also 
analyzed their potential cumulative effects. We incorporate the 
cumulative effects into our SSA analysis when we characterize the 
current and future condition of the subspecies. To assess the current 
and future condition of the subspecies, we undertake an iterative 
analysis that encompasses and incorporates the threats individually and 
then accumulates and evaluates the effects of all the factors that may 
be influencing the subspecies, including threats and conservation 
efforts. Habitat loss and fragmentation, human-caused hydrologic 
alteration, livestock grazing, genetic isolation, exotic plant 
invasion, climate change, climate events, larval desiccation, and 
collecting are all factors that influence or could influence the 
subspecies' viability. These factors also have the potential to act 
cumulatively to impact silverspot viability and their cumulative 
impacts were considered in our characterization of the subspecies' 
current and future condition in the SSA. Because the SSA framework 
considers not just the presence of the factors, but to what degree they 
collectively influence risk to the entire subspecies, our assessment 
integrates the cumulative effects of factors and replaces a standalone 
cumulative effects analysis.
Beneficial Factors
    Mowing or Haying: Mowing or haying occasionally or once a year 
could be beneficial to open the canopy for violets, reduce a buildup of 
thatch from dead vegetation, and keep woody vegetation from encroaching 
beyond what is suitable for the butterfly. Mowing or haying may 
approximate disturbance that would have occurred historically from 
native ungulate grazing and/or wildfire. Mowing in the early summer 
would allow for regrowth of vegetation and nectar sources suitable for 
the silverspot (Ellis 2020d, pers. comm.). However, mowing once in the 
late summer or early fall could potentially be compatible (Smith 2019, 
pers. comm.) but has a higher risk of reducing vegetation and nectar 
sources for that year's pupae and adults and possibly crushing pupae, 
eggs, and larvae. Occasional or once-yearly mowing can, nonetheless, be 
beneficial to reduce competition from other plants if adequate nectar 
sources remain in the field or if there are enough within a short 
distance around the field to supply nectar to adult silverspots.
    Grazing: Winter and spring grazing (October to mid-April) can be 
beneficial to silverspots (Arnold 1989, pp. 14-15). This is because 
removal of thatch from the dead vegetation limits competition in the 
spring for the violets and can reduce woody vegetation so that it does 
not encroach beyond what is suitable for the butterfly. It also may 
approximate historical grazing patterns by native ungulates (deer and 
elk), which come down to lower valleys in the winter where there is 
less snow. Horses grazed an apparently healthy colony in the spring and 
summer (Arnold 1989, p. 14), so some light to moderate grazing in the 
spring or summer may be acceptable. In contrast, grazing when violets 
have emerged and are actively growing (spring and summer) may be 
detrimental if livestock readily consume or trample the violets and 
possibly eggs, larvae, and pupae.
    Burning: Burning of meadows to reduce dead vegetation and reduce 
woody vegetation to suitable levels for the butterfly can also be 
beneficial and can possibly increase violet density (Arnold 1989, p. 
14; Ellis 1989, p. 14).
    Exotic Plant Invasion: Some exotic plants considered invasive or 
adventive may provide nectar sources that benefit silverspots (Ellis 
1989, p. 14; Fisher 2020b, pers. comm.). However, especially with 
invasive plants, this may only be the case where native nectar sources 
have been substantially reduced or eliminated.
    Conservation Efforts: The historical Unaweep Seep colony in the 
Mesa/Grand population was designated as a State Natural Area in 1983 
(Ellis 1999, p. 2). The Bureau of Land Management (BLM) also 
established a Research Natural Area around it in 1983 (Ellis 1989, p. 
1), and designated it as an Area of Critical Environmental Concern 
through their 2015 Resource Management Plan (Plank 2017, pers. comm.). 
Some monitoring, at least for the bog violet, occurred through 1999 
(Ellis 1999, entire), but sometime after 1989 or possibly 1999, the 
colony became extirpated (Ellis 1999, pp. 2, 7). Habitat monitoring 
actions were recommended, but it is unclear whether any of them were 
ever implemented (Ellis 1999, pp. 8-9). Although the State of Colorado 
and the BLM implemented land conservation designations around the 
Unaweep Seep colony in the Mesa/Grand population, this colony has been 
extirpated for at least 20 years. Therefore, unless the bog violet and 
silverspot are translocated back to Unaweep Seep, the land designations 
do not benefit the silverspot. There are no other State regulatory 
mechanisms that benefit the butterfly in Colorado, New Mexico, or Utah. 
The Colorado Wildlife Action Plan (WAP) includes the silverspot 
butterfly, but there are no State statutes for management of the 
silverspot, so management would occur through cooperative efforts with 
other agencies or organizations.
    The BLM (Colorado), U.S. Forest Service (USFS) Region 2 (Colorado), 
and USFS Region 3 (New Mexico) have the butterfly on their sensitive 
species lists. The USFS Region 4 (Utah) does not, but no silverspots 
are currently known on USFS land in Utah. No silverspot colonies are 
currently known on USFS land in Colorado or New Mexico either, but the 
elevational range of the subspecies includes some lower elevation USFS 
land. The BLM does not have the silverspot on its sensitive species 
lists in either Utah or New Mexico. If species are on BLM sensitive 
species lists, that means that the BLM works cooperatively with other 
Federal and State agencies and nongovernmental organizations to 
conserve these species and ensure that activities on public lands do 
not contribute to the need for their listing under the Act. Specific 
conservation objectives for BLM sensitive species are established in 
BLM land use plans. BLM's Grand Junction Field Office manages the 
Unaweep Seep property and mentions management of the area for the 
butterfly in their 2015 Resource Management Plan (Plank 2017, pers. 
comm.). The butterfly is not included in other BLM land use plans in 
any of the other BLM resource areas in Colorado, New Mexico, or Utah 
since the butterfly was not known to occur on BLM land in other areas 
until very recently (only one additional colony).

[[Page 26328]]

    Only three silverspot colonies are known to occur on public land 
(including State lands), but there is potentially a fourth colony 
(unconfirmed) on public land based on recent bog violet locations for 
the Garfield population. Consequently, at present, any regulatory 
mechanisms or conservation efforts on State, BLM, and USFS lands, 
although contributing to conservation of silverspots, would have a low 
impact on the silverspot's overall viability since the majority of 
populations and colonies are entirely or mostly on private land.

Current Condition

    We assessed current conditions of silverspot populations in 
relation to the ecological requirements of this subspecies. 
Measurements available that are consistent across populations are 
habitat patch size, number of colonies, and approximate distance 
between colonies within a population from which genetic connectivity 
can be estimated. Additionally, the presence and potential influence of 
the three major habitat factors affecting the subspecies (habitat loss 
and fragmentation, grazing, and hydrologic alteration) were derived 
from aerial imagery and/or on-the-ground knowledge. Therefore, these 
metrics are used to characterize the current resiliency condition of 
populations (see the SSA report's section 3.5 ``Current Condition by 
Population'' on how metric ranks were derived; Service 2021).
    Resiliency rankings and categories were established based on best 
available information and professional opinion of species experts. 
Habitat patch sizes are estimates based on expert opinion using aerial 
imagery based on best estimates of individual colony bog violet areas 
and primary nectar source areas. Determination of the number and status 
of colonies within a population was primarily based on expert input.
    There are 10 populations comprised of 19 colonies of the silverspot 
butterfly. Two populations, Archuleta and Garfield, were not included 
in the genetic analysis by Cong et al. (2019) due to a lack of samples, 
but we consider them to be part of the silverspot butterfly subspecies 
due to their geographic proximity to confirmed populations.
    Within the range and among all 10 populations, four known colonies 
have been extirpated. Three of these extirpations occurred relatively 
recently (in about the last 30 years) and one, Beulah, perhaps as long 
ago as 117 years (Scott and Fisher 2014, p. 3). Not including the 
extirpated colonies or stray sightings, and based on recent surveys or 
expert input, 19 colonies are considered extant that make up the 10 
populations.
    Resiliency for each population was scored using metrics for 
population size (in acres), number of colonies within populations, 
connectivity within populations, and habitat condition. Resiliency 
scores are categorized as follows: 0's: Predicted extirpation (future 
scenarios only); 1's: Very low resiliency; 2's and 3's: Low resiliency; 
4's to 6's: Moderate resiliency; 7's and above: High resiliency (Table 
1). According to our current condition analysis in the SSA report, five 
populations have very low resiliency. One population has low 
resiliency, two populations have moderate resiliency, and two 
populations have high resiliency (Table 1).

                    Table 1--Current Condition Resiliency Rankings for Silverspot Populations
----------------------------------------------------------------------------------------------------------------
                                                                                                    Population
                           Population                               Size in ac       Number of      resiliency
                                                                       (ha)          colonies          score
----------------------------------------------------------------------------------------------------------------
Archuleta.......................................................      11.9 (4.8)               1               1
Conejos.........................................................     39.2 (15.9)               1               3
Costilla........................................................       4.3 (1.7)               1               1
Garfield........................................................        1.0 (.4)               1               1
La Plata........................................................       5.2 (2.1)               1               1
Mesa/Grand......................................................     66.4 (26.9)               6               9
Montrose/San Juan...............................................        1.0 (.4)               2               4
Ouray...........................................................       59.3 (24)               3               6
San Miguel/Mora.................................................        1.0 (.4)               1               1
Taos............................................................   521.2 (210.9)               2               8
----------------------------------------------------------------------------------------------------------------

    With 10 populations spread across 284 air miles (457 km) north to 
south and 237 air miles (381 km) east to west, there appears to be 
adequate redundancy should catastrophic events occur that cause 
extirpation of one or a few populations. However, if catastrophic 
events cause extirpation of the populations with the highest resiliency 
(Mesa/Grand, Taos, and Ouray), it could be quite detrimental to the 
viability of the subspecies because six of the remaining populations 
have very low or low resiliency. Due to the uncertainty as to whether 
all populations are truly extant, and due to low resiliency of many 
populations, more populations with sufficient resiliency would 
contribute to the subspecies' viability. However, assuming all 
populations are still extant, we consider the current condition of the 
subspecies' redundancy to be moderate.
    Eight silverspot butterfly populations were identified based on 
genetic differentiation (Cong et al. 2019, entire). The other two 
populations were designated as such because they are more than 20 air 
miles (32 km) away from other populations (41 and 80 mi (66 and 129 
km)) and it is likely populations more than 20 mi (32 km) apart are not 
genetically connected (Ellis 2020c, pers. comm.; Grishin 2020b, pers. 
comm.). It is likely these genetic differences provide some 
adaptability, or representation. However, since many of the populations 
are comprised of a single colony and all populations appear isolated 
from one another, genetic drift could be causing limited genetic 
diversity, which is a concern for the subspecies. The 10 silverspot 
populations capture the genetic and ecological variation currently 
known for this subspecies. In general, the bog violet and butterfly 
occur in the same habitat across the range, but ecological 
representation adds to adaptive capacity since the silverspot occurs at 
different elevations, so that overall, the silverpot has low to 
moderate representation. Future analysis of ecological settings at all 
colonies/populations is needed to improve our understanding of 
representation across the subspecies' range.
    In summary, there are currently 19 colonies representing the 10

[[Page 26329]]

populations that are considered extant. In terms of resiliency, five 
populations are in very low condition, one in low condition, two in 
moderate condition, and two in high condition. Current redundancy is 
determined to be moderate, and representation is thought to be low to 
moderate.

Future Condition

    In the SSA report, we forecast the resiliency of silverspot 
populations and the redundancy and representation of the subspecies 
over the next 30 years (to the year 2050) using a range of plausible 
future scenarios. We selected 30 years because climate model 
projections are relatively similar up to this point. Also, climate 
change impacts and human habitat impacts are likely to be the biggest 
drivers of changes to resiliency, redundancy, and representation for 
this subspecies. We used future climate projections developed for 
southern Colorado and northern New Mexico (Rangwala 2020a, 2020b). Four 
climate models captured the range of model projections; thus, we 
evaluate four future scenarios that capture the range of plausible 
futures. Three of the four models use representative concentration 
pathway (RCP; a greenhouse gas concentration trajectory) 4.5 and the 
fourth uses RCP8.5. RCP4.5 is considered a medium emissions scenario. 
RCP8.5 is considered a high emissions scenario. The higher the 
emissions, the greater chance the climate will change further from the 
1971-2000 baseline. Current policies are projected to take us slightly 
above the RCP4.5 emission trends by mid-century (Hausfather and Peters 
2020, p. 260). The climate models are presented in tables 5 and 6 in 
the SSA report (Service 2021).
    Using the four climate scenarios, we developed four future 
condition scenarios to evaluate the future viability of the subspecies. 
In simple terms, the four scenarios include:

Scenario 1: Warm Climate with Conservation Efforts
Scenario 2: Hot and Dry Summers/Very Wet Winters with Conservation 
Efforts
Scenario 3: Very Hot and Very Dry Summers/Wet Winters with No 
Conservation Efforts
Scenario 4: Hot and Very Dry Summers/Dry Winters with No Conservation 
Efforts

    In addition to the effects of climate change, we also considered 
effects of human-caused impacts. In evaluating the effects of scenarios 
on silverspot populations, if available information indicated hydrology 
of colonies/populations will be impacted by human activity a negative 
habitat factor rank was applied to future resiliency scores (Service 
2021, p. 46).
    Because Scenarios 1 and 2 considered potential future conservation 
efforts, which are not certain to occur and are not formalized in any 
conservation agreements, we did not consider these scenarios when 
determining if the silverspot meets the Act's definition of an 
endangered species or of a threatened species. However, scenarios 1 and 
2 will inform our strategies for recovery of the species. Therefore, 
our analysis in this proposed rule focuses on the future condition of 
the silverspot under scenarios 3 and 4, as summarized below. Refer to 
the SSA report for full descriptions of the future scenarios (Service 
2021, chapter 4).
Scenario 3
    Scenario 3 is characterized as follows:
    <bullet> Some increase in direct habitat loss due to development 
occurs, particularly in colonies close to existing housing development.
    <bullet> Habitat fragmentation due to agricultural conversion is 
not reduced.
    <bullet> Light to heavy summer grazing occurs.
    <bullet> No efforts are made to maintain current hydrology.
    <bullet> All populations will have a negative habitat factor rank 
due to climate-related hydrologic alteration whether there is 
surrounding development or not.
    <bullet> No translocations of butterflies are implemented, and 
genetic diversity remains in a likely low state.
    <bullet> Climate emissions follow RCP8.5.
Scenario 4
    Scenario 4 is characterized as follows:
    <bullet> Some increase in direct habitat loss due to development 
occurs, particularly in colonies close to existing housing development.
    <bullet> Habitat fragmentation due to agricultural conversion is 
not reduced.
    <bullet> Light to heavy summer grazing occurs.
    <bullet> No efforts are made to maintain current hydrology (but 
even if so, those efforts are ineffective in the face of extreme 
drought).
    <bullet> All populations will have a negative habitat factor rank 
due to climate-related hydrologic factors regardless of absence of 
nearby development or agricultural activity or existing development and 
no conservation efforts.
    <bullet> No translocations of butterflies are implemented, and 
genetic diversity remains in a likely low state.
    <bullet> Climate emissions follow RCP4.5.
Results of Scenarios 3 and 4
    Resiliency rankings for each population under Scenario 3 can be 
found in the SSA report (Service 2021, table 11; Table 2 below). Five 
of the previously ranked low or very low resiliency populations under 
current conditions are expected to become extirpated, one population 
has a very low resiliency, three are low resiliency, and the Ouray 
population retains a moderate resiliency passing the Mesa/Grand and 
Taos populations as the highest-ranking population. Extirpation of 
colonies will reduce resiliency and redundancy of populations, and will 
also undoubtedly decrease representation from the current condition, 
causing a decline in subspecies' viability compared to the current 
condition.
    Resiliency rankings for each population under Scenario 4 can be 
found in the SSA report (Service 2021, table 12). As in Scenario 3, it 
is expected that climate change will cause extirpation of all small 
colonies/populations under 12 ac (5 ha). The size of habitat in 
remaining populations increases very slightly in Colorado populations 
compared to Scenario 3. Habitat decreases in the Taos population from 
Scenario 3 but not enough to change the size ranking. With there being 
slightly less evaporative stress and slightly less frequency of severe 
drought under Scenario 4 compared to Scenario 3, remaining populations 
may, in turn, be slightly more resilient. However, using the resiliency 
ranking metrics in the SSA report, the increase in resiliency in 
Scenario 4, compared to Scenario 3, is not sufficient to change the 
ranking of these populations. Consequently, resiliency rankings are the 
same as those in Scenario 3, with five extirpated populations, one very 
low and three low resiliency populations, and only one moderately 
resilient population. Redundancy of populations also remains low, and 
representation is also decreased from the current condition.
Summary of Current and Future Conditions
    A comparison of the resiliency of each population for the current 
condition and future scenarios is presented below in Table 2 along with 
summaries of redundancy and representation (also Service 2021, table 
13). Currently, we have determined that five of the 10 extant 
populations of silverspot are in a very low resiliency condition, one 
is low resiliency, two are moderate resiliency, and two of the largest 
populations are in high resiliency

[[Page 26330]]

condition. With 10 populations spread across the subspecies' range, 
there appears to be adequate redundancy should catastrophic events 
occur that cause extirpation of one or a few populations, and we 
consider current redundancy to be moderate for the silverspot. It is 
likely there is representation of adaptability due to the genetic 
differences observed among populations. However, many of the 
populations are composed of a single colony, and all populations appear 
isolated genetically. In general, the bog violet and butterfly occur in 
the same habitat across the subspecies' range, but ecological 
representation adding to adaptive capacity through occurrence at 
different elevations gives a low-to-moderate subspecies representation 
currently.
    Climate is predicted to change significantly over the next 30 years 
in scenarios 3 and 4, resulting in conditions that cause resiliency, 
redundancy, representation to decrease, and thus the subspecies' 
viability is expected to decrease from the current condition. 
Resiliency rankings are the same for scenarios 3 and 4 with five 
extirpated populations, one very low and three low resiliency 
populations, and only one moderately resilient population. Redundancy 
of populations and representation are both reduced from the current 
condition.

 Table 2--Summary of Silverspot Resiliency, Redundancy, and Representation for Current Condition and Four Future
                                                    Scenarios
----------------------------------------------------------------------------------------------------------------
                                          Current condition        Future scenario 3        Future scenario 4
              Population                      resiliency               resiliency               resiliency
----------------------------------------------------------------------------------------------------------------
Archuleta............................  1......................  0......................  0.
Conejos..............................  3......................  2......................  2.
Costilla.............................  1......................  0......................  0.
Garfield.............................  1......................  0......................  0.
La Plata.............................  1......................  0......................  0.
Mesa/Grand...........................  9......................  3......................  3.
Montrose/San Juan....................  4......................  1......................  1.
Ouray................................  6......................  5......................  5.
San Miguel/Mora......................  1......................  0......................  0.
Taos.................................  8......................  3......................  3.
Redundancy...........................  Moderate...............  Very Low...............  Very Low.
Representation.......................  Low-Moderate...........  Low....................  Low.
----------------------------------------------------------------------------------------------------------------

Determination of Silverspot's Status

    Under the Act, 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 
(16 U.S.C. 1532(16)). 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 
endangered species or threatened species because of any of the 
following factors: (A) The present or threatened destruction, 
modification, or curtailment of its habitat or range; (B) 
overutilization for commercial, recreational, scientific, or 
educational purposes; (C) disease or predation; (D) the inadequacy of 
existing regulatory mechanisms; or (E) other natural or manmade factors 
affecting its continued existence.

Status Throughout All of Its Range

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the silverspot butterfly across its range in the United States. We 
found habitat loss and fragmentation (Factor A), incompatible livestock 
grazing (Factor A), human-caused hydrologic alteration (Factor A), and 
genetic isolation (Factor E) to be the main drivers of the subspecies' 
current condition, with the addition of the effects of climate change 
(Factor E) influencing future condition. These stressors all contribute 
to loss of habitat quantity and quality for the silverspot and for the 
bog violet, the plant on which silverspot larvae exclusively feed. 
These threats can currently occur anywhere in the range of the 
silverspot, and future effects of climate change are expected to be 
ubiquitous throughout the subspecies' range. The existing regulatory 
mechanisms (Factor D) do not significantly affect the subspecies or 
ameliorate these stressors; thus, these stressors continue and are 
predicted to increase in prevalence in the future.
    Under the two future scenarios considered in this evaluation, we 
expect some populations to become extirpated and resiliency of the 
remaining populations to decrease. This would result in decreased 
redundancy and representation in the future compared to the current 
condition.
    We find that the silverspot is not currently in danger of 
extinction because the subspecies is still widespread with multiple 
populations of various sizes and resiliency spread across its range, 
capturing known genetic and ecological variation. Therefore, the 
subspecies currently has sufficient redundancy and representation to 
withstand catastrophic events and maintain adaptability to changes. 
However, we expect that the stressors, individually and cumulatively, 
will reduce resiliency, redundancy, and representation within all parts 
of the range within the foreseeable future in light of future climate 
change effects.
    After evaluating threats to the subspecies and assessing the 
cumulative effect of the threats under the section 4(a)(1) factors, we 
find that the silverspot is likely to become endangered throughout all 
of its range within the foreseeable future. This finding is based on 
anticipated reductions in resiliency, redundancy, and representation in 
the future as a result of predicted loss and degradation of wet meadow 
habitat from the synergistic and cumulative interactions between 
climate change and other stressors. Climate change is predicted to 
increase temperatures and decrease water availability and snowpack

[[Page 26331]]

necessary to maintain the wet meadows that the silverspot and bog 
violet need. This, coupled with the continuation of other stressors 
that alter hydrology and cause habitat loss and fragmentation, is 
expected to impact the future viability of this subspecies. We can 
reasonably determine that both the future threats and the subspecies' 
responses to those threats are likely within a 30-year timeframe (i.e., 
the foreseeable future). Thus, after assessing the best available 
information, we determine that the silverspot 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.

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, 
2020 WL 437289 (D.D.C. Jan. 28, 2020) (Center for Biological 
Diversity), vacated the aspect 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'' (79 FR 37578; July 1, 2014) that provided that the Service 
does not undertake an analysis of significant portions of a species' 
range if the species warrants listing as threatened throughout all of 
its range. Therefore, we proceed to evaluating whether the species is 
endangered in a significant portion of its range--that is, whether 
there is any portion of the species' range for which both (1) the 
portion is significant; and (2) the species is in danger of extinction 
in that portion. Depending on the case, it might be more efficient for 
us to address the ``significance'' question or the ``status'' question 
first. We can choose to address either question first. Regardless of 
which question we address first, if we reach a negative answer with 
respect to the first question that we address, we do not need to 
evaluate the other question for that portion of the species' range.
    Following the court's holding in Center for Biological Diversity, 
we now consider whether there are any significant portions of the 
species' range where the species is in danger of extinction now (i.e., 
endangered). In undertaking this analysis for the silverspot, we choose 
to address the status question first--we consider information 
pertaining to the geographic distribution of both the subspecies and 
the threats that the subspecies faces to identify any portions of the 
range where the subspecies is endangered.
    For the silverspot, we considered whether the threats are 
geographically concentrated in any portion of the subspecies' range at 
a biologically meaningful scale. We examined the following threats: 
Habitat loss and fragmentation; livestock grazing; human-caused 
hydrologic alteration; genetic isolation; climate change; climate 
events; invasion by nonnative plants; larval desiccation; and 
collecting. These are all factors that influence or could influence the 
subspecies' viability, including cumulative effects. All of these 
threats are similar in scope, scale, and distribution across the range 
of the subspecies. The spatial distribution of these threats is evenly 
distributed throughout the range and not concentrated in any particular 
area. However, there are a number of smaller populations distributed 
throughout the range that are currently in low resiliency condition and 
therefore could experience an elevated risk of extinction in the future 
(see Tables 1 and 2). However, these smaller populations are not 
concentrated in their location and are not at risk of extinction 
currently, as described in our analysis above. Rather their risk of 
extinction is influenced by the predicted future effects of habitat 
loss and degradation, climate change, and to a lesser extent the other 
stressors analyzed in this rule. Thus, there are no portions of the 
subspecies' range where the subspecies has a different status from its 
rangewide status. Therefore, no portion of the 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 subspecies is likely to become in danger of extinction within the 
foreseeable future throughout all of its range. This is consistent with 
the courts' holdings in Desert Survivors v. Department of the Interior, 
No. 16-cv-01165-JCS, 2018 WL 4053447 (N.D. Cal. Aug. 24, 2018), and 
Center for Biological Diversity v. Jewell, 248 F. Supp. 3d, 946, 959 
(D. Ariz. 2017).

Determination of Status

    Our review of the best available scientific and commercial 
information indicates that the silverspot meets the Act's definition of 
a threatened species. Therefore, we propose to list the silverspot 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, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness, and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and other countries and calls for recovery actions to be carried 
out for listed species. The protection required by Federal agencies and 
the prohibitions against certain activities are discussed, in part, 
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 recovery planning process involves the 
identification of actions that are necessary to halt or reverse the 
species' decline by addressing the threats to its survival and 
recovery. The goal of this process is to restore listed species to a 
point where they are secure, self-sustaining, and functioning 
components of their ecosystems.
    Recovery planning consists of preparing draft and final recovery 
plans, beginning with the development of a recovery outline and making 
it available to the public within 30 days of a final listing 
determination. The recovery outline guides the immediate implementation 
of urgent recovery actions and describes the process to be used to 
develop a recovery plan. Revisions of the plan may be done to address 
continuing or new threats to the species, as new substantive 
information becomes available. The recovery plan also 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. Recovery teams (composed of 
species experts, Federal and State agencies, nongovernmental 
organizations, and stakeholders) are often established to develop 
recovery

[[Page 26332]]

plans. When completed, the recovery outline, draft recovery plan, and 
the final recovery plan will be available on our website (https://www.fws.gov/endangered), or from our Western Colorado Ecological 
Services Field Office (see FOR FURTHER INFORMATION CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    If this species is listed, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost-share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. In addition, 
pursuant to section 6 of the Act, the States of Colorado, New Mexico, 
and Utah would be eligible for Federal funds to implement management 
actions that promote the protection or recovery of the silverspot. 
Information on our grant programs that are available to aid species 
recovery can be found at: https://www.fws.gov/grants.
    Although the silverspot is only proposed for listing under the Act 
at this time, please let us know if you are interested in participating 
in recovery efforts for this subspecies. Additionally, we invite you to 
submit any new information on this subspecies whenever it becomes 
available and any information you may have for recovery planning 
purposes (see FOR FURTHER INFORMATION CONTACT).
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as an 
endangered or threatened species and with respect to its critical 
habitat, if any is designated. Regulations implementing this 
interagency cooperation provision of the Act are codified at 50 CFR 
part 402. Section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any action that is likely to jeopardize the 
continued existence of a species proposed for listing or result in 
destruction or adverse modification of proposed critical habitat. If a 
species is listed subsequently, section 7(a)(2) of the Act requires 
Federal agencies to ensure that activities they authorize, fund, or 
carry out are not likely to jeopardize the continued existence of the 
species or destroy or adversely modify its critical habitat. If a 
Federal action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into consultation with the 
Service.
    Federal agency actions within the subspecies' habitat that may 
require conference or consultation or both as described in the 
preceding paragraph include management and any other landscape-altering 
activities on Federal lands administered by the U.S. Fish and Wildlife 
Service, Bureau of Land Management, Bureau of Indian Affairs, Bureau of 
Reclamation, National Park Service, and U.S. Forest Service; issuance 
of section 404 Clean Water Act (33 U.S.C. 1251 et seq.) permits by the 
U.S. Army Corps of Engineers; Natural Resources Conservation Service 
land management actions with private landowners and other Federal or 
State agencies; construction, maintenance, and funding of Federal or 
State roads or highways by the Federal Highway Administration; and 
possibly land management or other activities by other Federal agencies 
(such as the Office of Surface Mining, Reclamation, and Enforcement; 
Federal Energy Regulatory Commission; Western Area Power 
Administration; Federal Aviation Administration; Federal Communication 
Commission; Federal Emergency Management Agency; Environmental 
Protection Agency, and Animal and Plant Health Inspection Service).
    It is our policy, as published in the Federal Register on July 1, 
1994 (59 FR 34272), to identify to the maximum extent practicable at 
the time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act. The intent of this 
policy is to increase public awareness of the effect of a proposed 
listing on proposed and ongoing activities within the range of the 
species proposed for listing. The discussion below regarding protective 
regulations under section 4(d) of the Act complies with our policy.

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

Background

    Section 4(d) of the Act contains two sentences. The first sentence 
states that the Secretary shall issue such regulations as she deems 
necessary and advisable to provide for the conservation of species 
listed as threatened. The U.S. Supreme Court has noted that statutory 
language like ``necessary and advisable'' demonstrates a large degree 
of deference to the agency (see Webster v. Doe, 486 U.S. 592 (1988)). 
Conservation is defined in the Act to mean the use of all methods and 
procedures which are necessary to bring any endangered species or 
threatened species to the point at which the measures provided pursuant 
to the Act are no longer necessary. Additionally, the second sentence 
of section 4(d) of the Act states that the Secretary may by regulation 
prohibit with respect to any threatened species any act prohibited 
under section 9(a)(1), in the case of fish or wildlife, or section 
9(a)(2), in the case of plants. Thus, the combination of the two 
sentences of section 4(d) provides the Secretary with wide latitude of 
discretion to select and promulgate appropriate regulations tailored to 
the specific conservation needs of the threatened species. The second 
sentence grants particularly broad discretion to the Service when 
adopting the prohibitions under section 9.
    The courts have recognized the extent of the Secretary's discretion 
under this standard to develop rules that are appropriate for the 
conservation of a species. For example, courts have upheld rules 
developed under section 4(d) as a valid exercise of agency authority 
where they prohibited take of threatened wildlife, or include a limited 
taking prohibition (see Alsea Valley Alliance v. Lautenbacher, 2007 
U.S. Dist. Lexis 60203 (D. Or. 2007); Washington Environmental Council 
v. National Marine Fisheries Service, 2002 U.S. Dist. Lexis 5432 (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 him [or her] with regard to the permitted activities for those 
species. He [or she] may, for example, permit taking, but not 
importation of such species, or he [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).
    Exercising this authority under section 4(d), we have developed a 
proposed rule that is designed to address the silverspot's specific 
threats and conservation needs.
    Although the statute does not require us to make a ``necessary and 
advisable'' finding with respect to the adoption of

[[Page 26333]]

specific prohibitions under section 9, we find that this rule as a 
whole satisfies the requirement in section 4(d) of the Act to issue 
regulations deemed necessary and advisable to provide for the 
conservation of the silverspot. As discussed above under Summary of 
Biological Status and Threats, we have concluded that the silverspot is 
likely to become in danger of extinction within the foreseeable future 
primarily due to the projected effects of climate change, habitat loss 
and fragmentation, incompatible livestock grazing, human-caused 
hydrologic alteration, and genetic isolation. The provisions of this 
proposed 4(d) rule would promote conservation of the silverspot by 
encouraging management of the landscape in ways that meet both land 
management considerations and the conservation needs of the silverspot. 
The provisions of this proposed rule are one of many tools that we 
would use to promote the conservation of the silverspot. This proposed 
4(d) rule would apply only if and when we make final the listing of the 
silverspot as a threatened species.
    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species. In 
addition, section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any agency action 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 
proposed critical habitat.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are actions on State, Tribal, local, or 
private lands that require a Federal permit (such as a permit from the 
U.S. Army Corps of Engineers under section 404 of the Clean Water Act 
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10 
of the Act) or that involve some other Federal action (such as funding 
from the Federal Highway Administration, Federal Aviation 
Administration, or the Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat--and actions 
on State, Tribal, local, or private lands that are not federally 
funded, authorized, or carried out by a Federal agency--do not require 
section 7 consultation.
    This obligation does not change in any way for a threatened species 
with a species-specific 4(d) rule. Actions that result in a 
determination by a Federal agency of ``not likely to adversely affect'' 
continue to require the Service's written concurrence and actions that 
are ``likely to adversely affect'' a species require formal 
consultation and the formulation of a biological opinion.

Provisions of the Proposed 4(d) Rule

    This proposed 4(d) rule would provide for the conservation of the 
silverspot by prohibiting the following activities, with certain 
exceptions (discussed below): Importing or exporting; possession and 
other acts with unlawfully taken specimens; delivering, receiving, 
transporting, or shipping in interstate or foreign commerce in the 
course of commercial activity; and selling or offering for sale in 
interstate or foreign commerce. In addition, anyone taking, attempting 
to take, or otherwise possessing a silverspot, or parts thereof, in 
violation of section 9 of the Act would be subject to a penalty under 
section 11 of the Act, with certain exceptions (discussed below).
    Under the Act, ``take'' means to harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt to engage in any 
such conduct. Some of these provisions have been further defined in 
regulations at 50 CFR 17.3. Take can result knowingly or otherwise, by 
direct and indirect impacts, intentionally or incidentally. Allowing 
incidental and intentional take in certain cases, such as for the 
purposes of scientific inquiry or monitoring, or to improve habitat 
availability and quality, would help preserve the silverspot's 
remaining populations, slow their rate of decline, and decrease 
synergistic, negative effects from other stressors.
    We may issue permits to carry out otherwise prohibited activities, 
including those described above, involving threatened wildlife under 
certain circumstances. Regulations governing permits are codified at 50 
CFR 17.32. With regard to threatened wildlife, a permit may be 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. The statute 
also contains certain exemptions from the prohibitions, which are found 
in sections 9 and 10 of the Act.
    We recognize the special and unique relationship with our State 
natural resource agency partners in contributing to conservation of 
listed species. State agencies often possess scientific data and 
valuable expertise on the status and distribution of endangered, 
threatened, and candidate species of wildlife and plants. State 
agencies, because of their authorities and their close working 
relationships with local governments and landowners, are in a unique 
position to assist us in implementing all aspects of the Act. In this 
regard, section 6 of the Act provides that we shall 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 silverspot that may result in 
otherwise prohibited take without additional authorization.
    As discussed above under Factors Influencing Subspecies Viability, 
incompatible livestock grazing, exotic plant invasion, prescribed 
burning, and use of pesticides affect the status of the silverspot both 
negatively and positively depending on how, when, and where they are 
done. Accordingly, this proposed 4(d) rule addresses activities to 
facilitate conservation and management of the silverspot where they 
currently occur and may occur in the future by excepting them from the 
Act's take prohibition under certain specific conditions. These 
activities are intended to increase management flexibility and 
encourage support for the conservation and habitat improvement of the 
silverspot. Under this proposed 4(d) rule, take would be prohibited, 
except for take incidental to an otherwise lawful activity caused by 
actions described in the exceptions to prohibitions in the proposed 
4(d) rule for the purpose of silverspot conservation or recovery.
    The proposed forms of allowable take are explained in more detail 
below. For all proposed forms of allowable take, reasonable care would 
have to be practiced to minimize the impacts from the actions. 
Reasonable care means limiting the impacts to the silverspot and its 
host plant (bog violet) by complying with all applicable Federal, 
State, and Tribal regulations for the activity in question; using 
methods and techniques that result in the least harm, injury, or death, 
as feasible; undertaking activities at the least impactful times (e.g., 
conducting activities that might

[[Page 26334]]

impact habitat during the flight season) and locations, as feasible; 
ensuring the number of individuals affected does not impact the 
existing populations; ensuring no introduction of invasive plant 
species; and preserving the genetic diversity of populations.
    Under the proposed 4(d) rule, incidental take of a silverspot 
butterfly would not be a violation of section 9 of the Act if it occurs 
as a result of the following activities. All activities and statements 
below only apply to habitat areas of silverspot that include wet meadow 
areas where bog violet are growing and immediately adjacent areas with 
nectar sources.

Livestock Grazing

    By excepting take of silverspot caused by grazing, we would 
acknowledge the positive role that some ranchers have already played in 
conserving the silverspot butterfly and the importance of preventing 
any additional loss and fragmentation of native grasslands and riparian 
habitat. Grazing may be an effective tool to improve silverspot habitat 
by opening up the habitat and reducing vegetation that competes with 
bog violet when carefully applied in cooperation and consultation with 
private landowners, public land managers, and grazing experts. Moderate 
vegetative utilization (40-55 percent) in late fall to early spring 
(October 15 to May 31) would be excepted under this proposed 4(d) rule. 
Resting pastures that include silverspot habitat is preferred in summer 
through fall (June 1 to October 14), but light grazing (less than 30 
percent utilization) during this time frame would also be excepted from 
take by reducing competition with the bog violet. Recovery of the 
silverspot will depend on the protection and restoration of high-
quality habitats supporting the bog violet on private lands and on 
public lands that are grazed by private individuals under lease or 
other agreements.

Annual Haying or Mowing

    Annual haying or mowing in early summer can be beneficial, or at 
least not detrimental, to silverspots by removing vegetation that 
competes with the bog violet. Therefore, we are proposing to except 
take from annual haying or mowing in silverspot habitat under the 
following conditions: Activities must occur in the early summer (June 
30 or earlier), and blade height would need to be a minimum of 6 
inches, with 8 inches or higher preferred in areas with bog violet to 
avoid cutting the violet leaves. The timing of cutting also applies to 
surrounding drier areas important for nectaring, but blade height could 
be lower than 6 inches where the violet is not present. However, haying 
or mowing from July 1 through October would be detrimental due to 
removal of nectar sources and cover for all silverspot life stages, and 
therefore would not be excepted from the prohibitions in the proposed 
4(d) rule in and adjacent to bog violet habitat.

Prescribed Burning

    Spring burning can be beneficial to remove thatch that may reduce 
or prevent growth of the bog violet. Prescribed burning in the spring 
(March 1 to April 30) has limited impact to silverspots and would be 
excepted from take. Fall burning (October 15 to December 15) would also 
be excepted if the silverspot butterfly has been shown to not be 
present in a given year through adequate monitoring (i.e., multiple 
surveys at times when butterflies are active).

Brush Control

    Some woody vegetation interspersed in silverspot habitat or at the 
margins of habitat can be beneficial. However, if allowed to become too 
dense, woody vegetation can crowd out bog violets and nectar sources. 
Consequently, brush removal every 4 to 5 years would be excepted from 
take. Removal can be by mechanical means, burning, grazing, or 
herbicide application if in compliance with other excepted activities 
in the proposed 4(d) rule. If mechanical means such as a brush hog is 
used, the blade would need to be set to 8 inches or higher. If 
herbicides are used, an appropriate systemic herbicide to prevent 
regrowth would need to be applied to cut stems. Broadcast spraying in 
silverspot habitat would be prohibited because it may remove all nectar 
sources for the butterfly.

Noxious Weed Control

    Although some noxious weeds like Canada thistle may provide nectar 
sources for silverspot, spot spraying, hand pulling, or mowing of 
noxious weeds would be excepted from take. High densities of noxious 
weeds can be detrimental to the bog violet and their control can 
benefit the silverspot. However, broadcast spraying in silverspot 
habitat would be prohibited because it may remove all nectar sources 
for the butterfly.

Fence Maintenance

    Proposed excepted activities related to fence maintenance include 
replacement of poles and wire, and aboveground removal of woody 
vegetation along fence lines. Fences help manage where cattle can graze 
and reduce unwanted impacts to bog violet habitat. Removal of woody 
vegetation can prevent encroachment of vegetation into bog violet 
habitat and reduces competition with bog violet. If removal of woody 
vegetation is done by machine, such as a brush hog, the machine blade 
would need to be set 8 inches or higher above ground to avoid or 
minimize damage to the butterfly's host plant (bog violet). We 
recommend a systemic herbicide applied to the cut stems of woody 
vegetation.

Maintenance of Other Structures

    Maintenance of other existing structures within and immediately 
adjacent to silverspot habitat would be excepted if activities are kept 
within the confines of already disturbed ground so as to not disturb 
the subspecies or its habitat.
    Nothing in this proposed 4(d) rule would change in any way the 
recovery planning provisions of section 4(f) of the Act, the 
consultation requirements under section 7 of the Act, or our ability to 
enter into partnerships for the management and protection of the 
silverspot. However, interagency cooperation may be further streamlined 
through planned programmatic consultations for the subspecies between 
us and other Federal agencies, where appropriate. We ask the public, 
particularly State agencies and other interested stakeholders that may 
be affected by the proposed 4(d) rule, to provide comments and 
suggestions regarding additional guidance and methods that the Service 
could provide or use, respectively, to streamline the implementation of 
this proposed 4(d) rule (see Information Requested, above).

III. Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) Essential to the conservation of the species, and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Our regulations at 50 CFR 424.02 define the geographical area 
occupied

[[Page 26335]]

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). Additionally, our regulations 
at 50 CFR 424.02 define the word ``habitat,'' for the purposes of 
designating critical habitat only, as the abiotic and biotic setting 
that currently or periodically contains the resources and conditions 
necessary to support one or more life processes of a species.
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the destruction or adverse modification of 
critical habitat. The designation of critical habitat does not affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. 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. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the Federal agency would be required to consult 
with the Service under section 7(a)(2) of the Act. However, even if the 
Service were to conclude that the proposed activity would 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 designation if they 
contain physical or biological features (1) which are essential to the 
conservation of the species and (2) which may require special 
management considerations or protection. For these areas, critical 
habitat designations identify, to the extent known using the best 
scientific and commercial data available, those physical or biological 
features that are essential to the conservation of the species (such as 
space, food, cover, and protected habitat). In identifying those 
physical or biological features that occur in specific occupied areas, 
we focus on the specific features that are essential to support the 
life-history needs of the species, including, but not limited to, water 
characteristics, soil type, geological features, prey, vegetation, 
symbiotic species, or other features. A feature may be a single habitat 
characteristic or a more complex combination of habitat 
characteristics. Features may include habitat characteristics that 
support ephemeral or dynamic habitat conditions. Features may also be 
expressed in terms relating to principles of conservation biology, such 
as patch size, distribution distances, and connectivity.
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species. The implementing regulations at 50 CFR 424.12(b)(2) further 
delineate unoccupied critical habitat by setting out three specific 
parameters: (1) When designating critical habitat, the Secretary will 
first evaluate areas occupied by the species; (2) the Secretary will 
consider unoccupied areas to be essential only where a critical habitat 
designation limited to geographical areas occupied by the species would 
be inadequate to ensure the conservation of the species; and (3) for an 
unoccupied area to be considered essential, the Secretary must 
determine that there is a reasonable certainty both that the area will 
contribute to the conservation of the species and that the area 
contains one or more of those physical or biological features essential 
to the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 
habitat.

Prudency Determination

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

[[Page 26336]]

are concerned that designation of critical habitat would more widely 
announce the exact locations of silverspots to collectors. We believe 
that the publication of maps and descriptions outlining the locations 
of the silverspot would further facilitate unauthorized collection and 
trade, as collectors would know the exact locations where silverspots 
occur.
    Although we do not have recent evidence of collection of the 
silverspot butterfly, we believe this is due to the public being 
largely unaware of where the silverspot butterfly occurs. Recent 
genetic studies reclassifying the multiple subspecies of nokomis may 
serve to increase interest in butterfly collection. In addition, 
collection of butterflies would be extremely difficult to detect, given 
the remote locations where the silverspot occurs. The silverspot has 
been collected in the past, and there is potential for collection 
pressure to increase if specific locations of populations were to 
become widely known (Ellis 2020e, pers. comm.; Scott 2020, pers. 
comm.). Butterflies in general are highly sought after by collectors in 
the illegal animal trade (Speart 2012, entire). Some experts have 
expressed concern that small populations/colonies of this subspecies 
could be impacted by collection pressure if it were to increase after 
the subspecies is listed (Scott 2020, pers. comm.). Experts have noted 
that individuals from small populations should not be collected (Scott 
2020, pers. comm.). Many of the extant populations of the silverspot 
are small and currently in low resiliency condition, and therefore 
could be easily extirpated if collection pressure increased. The 
silverspot's annual life cycle also lends itself to increased negative 
population-level impacts if over-collection were to occur. We know of 
one example of a potential silverspot colony extirpation related to 
over-collection (combined with vegetation changes) (Scott 2020, pers. 
comm.). Many populations are on private land and locations of occupied 
colonies are currently not widely known. Therefore, publishing specific 
location information would provide a high level of assurance that any 
person going to a specific location would be able to successfully 
locate and collect silverspots given the subspecies' site fidelity and 
ease of capture once located. Identification of locations of 
populations through publication of a critical habitat designation for 
the silverspot can be expected to increase the degree of collection 
threat to the subspecies.
    In conclusion, we find that the designation of critical habitat is 
not prudent for the silverspot, in accordance with 50 CFR 424.12(a)(1), 
because the silverspot faces a threat of unauthorized collection and 
trade, and designation can reasonably be expected to increase the 
degree of these threats to the subspecies.

Required Determinations

Clarity of the Rule

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

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

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be 
prepared in connection with listing a species as an endangered or 
threatened species under the Endangered Species Act. We published a 
notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244).

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), Executive Order 13175 (Consultation and 
Coordination with Indian Tribal Governments), and the Department of the 
Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. In accordance with 
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, 
Federal-Tribal Trust Responsibilities, and the Endangered Species Act), 
we readily acknowledge our responsibilities to work directly with 
Tribes in developing programs for healthy ecosystems, to acknowledge 
that Tribal lands are not subject to the same controls as Federal 
public lands, to remain sensitive to Indian culture, and to make 
information available to Tribes. Thirty-eight Tribes with cultural 
claims or affiliation to land or with lands currently in the range of 
the silverspot were contacted via letter to solicit input on the SSA. 
One Tribe responded and stated that they do not have scientific data 
but would like to be kept informed of findings of the SSA. We have 
determined that critical habitat is not prudent for the silverspot, so 
no Tribal lands (or other lands) will be included in a proposed 
critical habitat designation.

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 Western Colorado Ecological Services Field Office (see FOR FURTHER 
INFORMATION CONTACT).

Authors

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

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

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

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

0
2. Amend Sec.  17.11, in paragraph (h), by adding an entry for 
``Butterfly, silverspot'' to the List of Endangered and Threatened 
Wildlife in alphabetical order under INSECTS to read as follows:

[[Page 26337]]

Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

----------------------------------------------------------------------------------------------------------------
                                                                                          Listing citations and
           Common name              Scientific name      Where listed         Status         applicable rules
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
             Insects
 
                                                  * * * * * * *
Butterfly, silverspot...........  Speyeria nokomis    Wherever found....  T              [Federal Register
                                   nokomis.                                               citation when
                                                                                          published as a final
                                                                                          rule]; 50 CFR
                                                                                          17.47(h).\4d\
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

0
3. As proposed to be amended at 85 FR 1018 (January 8, 2020), 85 FR 
64908 (October 13, 2020), and 86 FR 32859 (June 23, 2021), Sec.  17.47 
is further amended by adding a paragraph (h) to read as follows:


Sec.  17.47  Special rules--insects.

* * * * *
    (h) Silverspot butterfly (Speyeria nokomis nokomis).
    (1) Prohibitions. The following prohibitions that apply to 
endangered wildlife also apply to silverspot butterfly. Except as 
provided under paragraphs (h)(2) and (3) of this section and Sec. Sec.  
17.4 and 17.5, it is unlawful for any person subject to the 
jurisdiction of the United States to commit, to attempt to commit, to 
solicit another to commit, or cause to be committed, any of the 
following acts in regard to this species:
    (i) Import or export, as set forth at Sec.  17.21(b) for endangered 
wildlife.
    (ii) Take, as set forth at Sec.  17.21(c)(1) for endangered 
wildlife.
    (iii) Possession and other acts with unlawfully taken specimens, as 
set forth at Sec.  17.21(d)(1) for endangered wildlife.
    (iv) Interstate or foreign commerce in the course of a 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) General exceptions from prohibitions. In regard to this 
species, you may:
    (i) Conduct activities as authorized by a permit under Sec.  17.32.
    (ii) Take, as set forth at Sec.  17.21(c)(2) through (c)(4) for 
endangered wildlife.
    (iii) Take as set forth at Sec.  17.31(b).
    (iv) Possess and engage in other acts with unlawfully taken 
wildlife, as set forth at Sec.  17.21(d)(2) for endangered wildlife.
    (3) Exceptions from prohibitions for specific types of incidental 
take. You may take silverspot butterfly without a permit in wet meadow 
areas where bog violets (Viola nephrophylla/V. sororia var. affinis) 
are growing and immediately adjacent areas with nectar sources while 
carrying out the legally conducted activities set forth in this 
paragraph (h)(3), as long as the activities:
    (i) Are conducted with reasonable care. For the purposes of this 
paragraph, ``reasonable care'' means limiting the impacts to the 
silverspot and bog violet by complying with all applicable Federal, 
State, and Tribal regulations for the activity in question; using 
methods and techniques that result in the least harm, injury, or death, 
as feasible; undertaking activities at the least impactful times (e.g., 
conducting activities that might impact habitat during the flight 
season) and locations, as feasible; ensuring the number of individuals 
affected does not impact the existing populations; ensuring no 
introduction of invasive plant species; and preserving the genetic 
diversity of populations;
    (ii) Consist of one or more of the following:
    (A) Grazing:
    (1) Moderate grazing (40 to 55 percent vegetative utilization) in 
late fall to early spring (October 15 to May 31); or
    (2) Light grazing (less than 30 percent vegetative utilization) in 
summer through fall (June 1 to October 14).
    (B) Annual haying or mowing in silverspot habitat in the early 
summer (June 30 or earlier). Blade height must be a minimum of 6 
inches, with 8 inches or higher preferred in areas with bog violet. In 
surrounding drier areas, blade height may be lower than 6 inches where 
the violet is not present.
    (C) Prescribed burning:
    (1) In the spring (March 1 to April 30); or
    (2) In the fall (October 15 to December 15), if the silverspot 
butterfly has been shown to not be present in a given year through 
adequate monitoring (i.e., multiple surveys at times when butterflies 
are active).
    (D) Brush removal every 4 to 5 years. Removal can be by mechanical 
means, burning, grazing, or herbicide application if in compliance with 
other excepted activities in this paragraph (h)(3). If mechanical means 
such as a brush hog is used, the blade must be set to 8 inches or 
higher. If herbicides are used, an appropriate systemic herbicide to 
prevent regrowth must be applied to cut stems, but broadcast spraying 
is prohibited.
    (E) Spot spraying, hand pulling, or mowing of noxious weeds. 
Broadcast spraying of noxious weeds is prohibited.
    (F) Replacement of fence poles and wire, and aboveground removal of 
woody vegetation along fence lines. If removal of woody vegetation is 
done by machine, such as a brush hog, the machine blade must be set 8 
inches or higher. We recommend a systemic herbicide applied to the cut 
stems of woody vegetation.
    (G) Maintenance of other existing structures within and immediately 
adjacent to silverspot habitat if activities are kept within the 
confines of already disturbed ground.

Martha Williams,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2022-09446 Filed 5-3-22; 8:45 am]
BILLING CODE 4333-15-P