Proposed Rule2022-09446
Endangered and Threatened Wildlife and Plants; Threatened Species Status With Section 4(d) Rule for the Silverspot Butterfly
Primary source
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Published
May 4, 2022
Issuing agencies
Interior DepartmentFish and Wildlife Service
Abstract
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.
Full Text
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[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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: <a href="https://www.regulations.gov">https://www.regulations.gov</a>. 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
[[Page 26320]]
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 <a href="https://www.regulations.gov">https://www.regulations.gov</a>. 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a> 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a>, 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 <a href="https://www.regulations.gov">https://www.regulations.gov</a>.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on <a href="https://www.regulations.gov">https://www.regulations.gov</a>.
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
[[Page 26322]]
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 <a href="https://www.regulations.gov">https://www.regulations.gov</a>.
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
[[Page 26323]]
(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
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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 (<a href="https://www.fws.gov/endangered">https://www.fws.gov/endangered</a>), 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: <a href="https://www.fws.gov/grants">https://www.fws.gov/grants</a>.
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 <a href="https://www.regulations.gov">https://www.regulations.gov</a> 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
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</html>Indexed from Federal Register on May 4, 2022.
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