[Federal Register Volume 77, Number 171 (Tuesday, September 4, 2012)]
[Proposed Rules]
[Pages 54294-54329]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-21243]



[[Page 54293]]

Vol. 77

Tuesday,

No. 171

September 4, 2012

Part III





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





Endangered and Threatened Wildlife and Plants; 12-Month Finding on a 
Petition To List Four Subspecies of Great Basin Butterflies as 
Endangered or Threatened Species; Proposed Rule

  Federal Register / Vol. 77 , No. 171 / Tuesday, September 4, 2012 / 
Proposed Rules  

[[Page 54294]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R8-ES-2012-0058; 4500030113]


Endangered and Threatened Wildlife and Plants; 12-Month Finding 
on a Petition To List Four Subspecies of Great Basin Butterflies as 
Endangered or Threatened Species

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 12-month petition finding.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a 
12-month finding on a petition to list four subspecies of Great Basin 
butterflies (White River Valley skipper (Hesperia uncas grandiosa), 
Steptoe Valley crescentspot (Phyciodes cocyta arenacolor), Baking 
Powder Flat blue butterfly (Euphilotes bernardino minuta), and bleached 
sandhill skipper (Polites sabuleti sinemaculata)) in Nevada as 
endangered or threatened species and designate critical habitat under 
the Endangered Species Act of 1973, as amended (Act). After review of 
the best available scientific and commercial information, we find that 
listing these four butterfly and skipper subspecies is not warranted at 
this time. However, we ask the public to submit to us any new 
information that becomes available concerning the threats to the White 
River Valley skipper, Steptoe Valley crescentspot, Baking Powder Flat 
blue butterfly, and bleached sandhill skipper or their habitats at any 
time.

DATES: The finding announced in this document was made on September 4, 
2012.

ADDRESSES: This finding is available on the internet at http://www.regulations.gov at Docket Number FWS-R8-ES-2012-0058. The 
supporting documentation we used in preparing this finding is available 
for public inspection, by appointment, during normal business hours at 
the U.S. Fish and Wildlife Service, Nevada Fish and Wildlife Office, 
1340 Financial Boulevard, Suite 234, Reno, NV 89502. Please submit any 
new information, materials, comments, or questions concerning this 
finding to the above address.

FOR FURTHER INFORMATION CONTACT: Edward D. Koch, State Supervisor, 
Nevada Fish and Wildlife Office (see ADDRESSES); by telephone (775-861-
6300), or by facsimile (775-861-6301). If you use a telecommunications 
device for the deaf (TDD), please call the Federal Information Relay 
Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    Section 4(b)(3)(B) of the Act (16 U.S.C. 1531 et seq.), requires 
that, for any petition to revise the Lists of Endangered and Threatened 
Wildlife and Plants that contains substantial scientific or commercial 
information that the listing may be warranted, we make a finding within 
12 months of the date of the receipt of the petition. In this finding, 
we will determine that the petitioned action is either: (1) Not 
warranted, (2) warranted, or (3) warranted, but the immediate proposal 
of a regulation implementing the petitioned action is precluded by 
other pending proposals to determine whether species are an endangered 
or threatened species, and expeditious progress is being made to add or 
remove qualified species from the Lists of Endangered and Threatened 
Wildlife and Plants. Section 4(b)(3)(C) of the Act requires that we 
treat a petition for which the requested action is found to be 
warranted but precluded as though resubmitted on the date of such 
finding; that is, requiring a subsequent finding to be made within 12 
months. We must publish these 12-month findings in the Federal 
Register.

Previous Federal Actions

    These four subspecies were included in our Category 2 candidate 
list for November 21, 1991 (56 FR 58804). A Category 2 candidate 
species was a species for which we had information indicating that a 
proposal to list it as threatened or endangered under the Act may be 
appropriate, but for which additional information on biological 
vulnerability and threat was needed to support the preparation of a 
proposed rule. Please see Table 1 to cross reference the names on the 
1991 Category 2 candidate list with the names of the four subspecies 
petitioned for listing.

          Table 1--Four Great Basin, NV, butterflies: Previous and Current Common and Scientific Names
----------------------------------------------------------------------------------------------------------------
                          Common name                                            Scientific name
----------------------------------------------------------------------------------------------------------------
               Previous                        Current                  Previous                 Current
----------------------------------------------------------------------------------------------------------------
White River Valley skipper...........  White River Valley       Hesperia uncas ssp.....  Hesperia uncas
                                        skipper.                                          grandiosa
Steptoe Valley crescentspot..........  Steptoe Valley           Phyciodes pascoensis     Phyciodes cocyta
                                        crescentspot.            ssp.                     arenacolor
Baking Powder Flat blue butterfly....  Baking Powder Flat blue  Euphilotes battoides     Euphilotes bernardino
                                        butterfly.               ssp.                     minuta
Denio sandhill skipper...............  Bleached sandhill        Polites sabuleti         Polites sabuleti
                                        skipper.                 sinemaculata.            sinemaculata
----------------------------------------------------------------------------------------------------------------

    In the February 28, 1996, Candidate Notice of Review (CNOR) (61 FR 
7595), we adopted a single category of candidate species defined as 
follows: ``Those species for which the Service has on file sufficient 
information on biological vulnerability and threat(s) to support 
issuance of a proposed rule to list but issuance of the proposed rule 
is precluded.'' In previous CNORs, species meeting this definition were 
known as Category 1 candidates for listing. Thus, as of the 1996 CNOR, 
the Service no longer considered Category 2 species as candidates, 
including the four petitioned butterfly and skipper subspecies, and did 
not include them in the 1996 candidate list or any subsequent CNORs. 
The decision to no longer consider Category 2 species as candidates was 
designed to reduce confusion about the status of these species and to 
clarify that we no longer regarded these species as candidates for 
listing.
    On January 29, 2010, we received a petition dated January 25, 2010, 
from WildEarth Guardians requesting that 10 subspecies of Great Basin 
butterflies in Nevada and California be listed as endangered or 
threatened species with critical habitat under the Act. The 10 
subspecies of Great Basin butterflies are: White River Valley skipper, 
Steptoe Valley crescentspot, Baking Powder Flat blue butterfly, 
bleached sandhill skipper, Carson Valley silverspot (Speyeria nokomis 
carsonensis), Carson Valley wood nymph (Cercyonis pegala carsonensis), 
Mono Basin skipper (Hesperia uncas giulianii), Railroad Valley skipper 
(Hesperia uncas fulvapalla), Railroad Valley skipper (Hesperia uncas 
reeseorum), and Mattoni's blue butterfly (Euphilotes

[[Page 54295]]

pallescens mattonii). In a March 26, 2010, letter to the petitioner, we 
responded that we had reviewed the information presented in the 
petition and determined that issuing an emergency regulation 
temporarily listing the 10 subspecies as per section 4(b)(7) of the Act 
was not warranted, although this was not requested in the petition. On 
October 4, 2011, we made our 90-day finding that the petition did not 
present substantial scientific or commercial information indicating 
that listing 6 of the 10 subspecies (Carson Valley silverspot, Carson 
Valley wood nymph, Mattoni's blue butterfly, Mono Basin skipper, and 
the two Railroad Valley skipper subspecies) may be warranted (76 FR 
61532). However, we determined that the petition presented substantial 
scientific or commercial information indicating that listing of the 
other four subspecies (White River Valley skipper, Steptoe Valley 
crescentspot, Baking Powder Flat blue butterfly, and bleached sandhill 
skipper) may be warranted, and we initiated a status review for these 
subspecies. This notice constitutes the 12-month finding on the January 
29, 2010, petition to list the White River Valley skipper, Steptoe 
Valley crescentspot, Baking Powder Flat blue butterfly, and bleached 
sandhill skipper as endangered or threatened species and designate 
critical habitat under the Act.

Summary of Procedures for Determining the Listing Status of Species

Review of Status Based on Five Factors
    Section 4 of the Act (16 U.S.C. 1533) and its implementing 
regulations (50 CFR 424) set forth the procedures for adding a species 
to, removing species from, or reclassifying species on the Federal 
Lists of Endangered and Threatened Wildlife and Plants. Under section 
4(a)(1) of the Act, a species may be determined to be an endangered or 
threatened species based on any of the following 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.
    In making this finding, information pertaining to the White River 
Valley skipper, Steptoe Valley crescentspot, Baking Powder Flat blue 
butterfly, and bleached sandhill skipper in relation to the five 
factors provided in section 4(a)(1) of the Act is discussed below. In 
considering what factors might constitute threats, we must look beyond 
the mere exposure of the species to the factor to determine whether the 
species responds to the factor in a way that causes actual impacts to 
the species. If there is exposure to a factor, but no response, or only 
a positive response, that factor is not a threat. If there is exposure 
and the species responds negatively, the factor may be a threat, and we 
then attempt to determine how significant a threat it is. If the threat 
is significant, it may drive or contribute to the risk of extinction of 
the species such that the species may warrant listing as an endangered 
or threatened species as those terms are defined by the Act. This does 
not necessarily require empirical proof of a threat. The combination of 
exposure and some corroborating evidence of how the species is likely 
impacted could suffice. The mere identification of factors that could 
impact a species negatively is not sufficient to compel a finding that 
listing is appropriate; we require evidence that these factors are 
operative threats that act on the species to the point that the species 
may meet the definition of an endangered or threatened species under 
the Act.

Evaluation of the Status of Each of the Four Butterfly and Skipper 
Subspecies

    For each of the four butterfly and skipper subspecies, we provide a 
description of the subspecies and its habitat and biology, an 
evaluation of listing factors for that subspecies, and our finding as 
to whether the petitioned action is warranted or not for that 
subspecies.
    The four butterfly and skipper subspecies evaluated in this finding 
are invertebrates endemic to the Great Basin region of Nevada. The four 
subspecies are from the phylum Arthropoda, class Insecta, and order 
Lepidoptera. Taxonomic families for the four subspecies are: 
Hesperiidae, Nymphalidae, and Lycaenidae.
    The petition provides information regarding the four subspecies' 
rankings according to NatureServe, which considers the butterflies and 
skippers at the subspecies taxonomic level and ranks each as 
``critically imperiled'' or ``imperiled'' at the global, national, or 
State level (WildEarth Guardians 2010, pp. 3-4). While the petition 
states that these ``definitions of `critically imperiled' and 
`imperiled' are at least equivalent to definitions of `endangered' or 
`threatened' under the [Act],'' this is not an appropriate comparison. 
According to its own Web site, NatureServe's assessment of any species 
``does not constitute a recommendation by NatureServe for listing [that 
species]'' under the Act (NatureServe 2008, p. 1). In addition, 
NatureServe's assessment procedures include ``different criteria, 
evidence requirements, purposes and taxonomic coverage [from those of] 
government lists of endangered and threatened species, and therefore 
these two types of lists should not be expected to coincide'' 
(NatureServe 2008, p. 1).

Species Information for the White River Valley Skipper

Taxonomy and Species Description

    We accept the characterization of the White River Valley skipper 
(Hesperia uncas grandiosa) as a valid subspecies based on its 
description by Austin and McGuire (1998, p. 778). This subspecies is in 
the Hesperiidae family (Austin 1998a, p. 838). Male wingspans range 
from 0.63 to 0.7 inch (in) (16.0-17.6 millimeters (mm)). The upperside 
of the wings are clay color. The forewing margin is blackish. The apex 
has a large yellowish macule (spot, patch). The stigma (patch of scent 
scales) is broad and black with a silver central line. The hindwing has 
a black costa and narrow outer margin. The fringes of both wings are 
pale gray. The underside of the forewing is paler than the upperside. 
The apical macules are white. The area beneath the stigma and wing base 
is black. The hindwing is olive-gray colored. The postmedian and sub-
basal macules are white. The veins are white medially and extend to the 
outer margin (Austin and McGuire 1998, p. 778). Females range from 0.74 
to 0.82 in (18.8-20.7 mm). The upperside of the wings is similar to 
that of the males but is darker. The outer margin is broader than that 
of the males. The apical macules are paler. The hindwing is blacker 
than the male's hindwing. The fringes of both wings are very pale gray. 
The underside of the wing is similar to that of the male, but it is 
more blackish medially on the forewing. The hindwing postmedial macules 
are larger and the white on the hindwing veins extend to the outer 
margin usually (Austin and McGuire 1998, p. 778). Please refer to 
Austin and McGuire (1998, p. 778) for a more detailed description of 
this subspecies.

Distribution and Habitat

    Descriptions of locations where the White River Valley skipper has 
been found are rather vague. The White River Valley skipper's type 
locality (location where the specimen from which a species is described 
and named was collected) is a narrow marshy area in the

[[Page 54296]]

White River channel, White River Valley, located 1 mile (mi) (1.6 
kilometer (km)) north of the Nye County boundary in White Pine County, 
Nevada (Austin and McGuire 1998, p. 778; Nevada Natural Heritage 
Program (NNHP) 2010) (on private and Bureau of Land Management (BLM) 
administered lands). This area is approximately 1.5 mi (2.4 km) 
southwest of the Ruppes/Boghole area (White Pine County), where this 
subspecies has also been observed on BLM and private lands (NNHP 2006, 
p. 47). The subspecies is known from alkaline Distichlis spicata (salt 
grass) flats in the White River Valley from Sunnyside (includes the 
Flag Springs area) (Nye County) north to the type locality, a distance 
of about 20 mi (32 km) (on unspecified BLM and private lands), and from 
Big Smoky Valley at unspecified locations (northwestern Nye County) 
(Austin and McGuire 1998, p. 778). This subspecies was also found at 
Kirch Wildlife Management Area (WMA) (two areas at south ends of Tule 
and Adams-McGill Reservoirs (on State lands) (Nye County) (Boyd, pers. 
comm. 2012a, p. 2; b, p. 1) and at Moorman Springs (Nye County) (Boyd, 
pers. comm. 2012b, p. 1) (on BLM and private lands).
    A specimen that may be this subspecies was collected 1 mi (1.6 km) 
south of Blind Spring, Spring Valley (White Pine County) (Austin and 
McGuire 1998, p. 785). In 1998, Austin and McGuire (1998, pp. 778-779) 
tentatively included populations from Spring Valley (based on one male 
specimen) and Lake Valley (based on two male specimens with no site 
specificity given) (Lincoln County), Nevada, within the range of this 
subspecies. During a general terrestrial invertebrate survey conducted 
in 2006 at 76 locations in eastern Nevada, a single male was 
encountered east of Cleve Creek in Spring Valley (White Pine County) 
(Ecological Sciences, Inc. 2007, p. 28) and was attributed to this 
subspecies. This location is near other areas (not specified by 
authors) where the subspecies has been previously documented, and is 
not considered to be a significant range extension (Ecological 
Sciences, Inc. 2007, p. 28). The size of each known occupied site or 
the extent of this subspecies' host plant(s), or host plant abundance, 
has not been reported.

Biology

    The White River Valley skipper flies during June, July, and August 
(Austin and McGuire 1998, p. 778; Austin et al., in litt. 2000, p. 4). 
Though adult nectar sources have not been reported, it is possible that 
they nectar on a variety of plants that are in flower during their 
flight period. The apparent larval host plant is Juncus mexicanus 
(Mexican rush) (Austin and Leary 2008, p. 11). This perennial plant 
species occurs in moist habitats (Kartesz 1987, p. 1503; Reed 1988, pp. 
8, 10; Austin and Leary 2008, p. 11). In Nevada, it is known from 
western and southern counties, including Nye County (Kartesz 1987, p. 
1503; http://www plants.usda.gov Web site accessed April 24, 2012). In 
the western United States, in addition to Nevada, it occurs in Oregon, 
California, Arizona, New Mexico, Colorado, and Texas (http://www 
plants.usda.gov Web site accessed April 24, 2012).
    There is little biological information available at the subspecies 
level, but some inferences can be made from biological information from 
related species at the species level. Information for the white-vein 
skipper (Hesperia uncus) indicates eggs are pale greenish-white and are 
laid singly on or near the host plant (Scott 1986, p. 435). Larvae eat 
leaves, and they live in tied-leaf nests (Scott 1986, p. 435). Males 
perch during the day on small hill tops seeking females (Scott 1986, p. 
435).
    The best available information does not include surveys documenting 
this subspecies' population dynamics, nor its overall abundance, number 
or size of populations, number of extirpated populations, if any, or 
population trends.

Five-Factor Evaluation for the White River Valley Skipper

    Information pertaining to the White River Valley skipper in 
relation to the five factors provided in section 4(a)(1) of the Act is 
discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    Potential factors that may affect the habitat or range of the White 
River Valley skipper are discussed in this section, including: (1) 
Water development, (2) land development, (3) livestock grazing, (4) 
nonnative plant invasion, (5) agriculture, (6) mining and energy 
development, and (7) climate change.
Water Development
    Riparian communities and associated springs, seeps, and small 
streams comprise a small area of the Great Basin and Mojave Desert 
regions, but provide habitat for 70 percent of the butterfly species in 
these regions (Brussard and Austin 1993, cited in Brussard et al. 1998, 
p. 508). The petition suggests that the historical range for the 
petitioned butterfly and skipper subspecies has been reduced (WildEarth 
Guardians 2010, p. 6), but specific supporting information is not 
provided. Habitat associated with riparian and aquatic habitats, 
including springs and seeps, has been reduced in Nevada due to various 
purposes such as water diversions, development, livestock grazing, 
recreation, mining, and power generation (Sada et al. 1992, p. 76; Noss 
et al. 1995, p. 76; Brussard et al. 1998, pp. 531-532; Sada et al. 
2001, pp. 11-16; Sada 2008, pp. 49-50). Commitments of water resources 
beyond perennial yield may result in detrimental impacts to habitats in 
a designated basin. Groundwater extraction that exceeds aquifer 
recharge may result in surface water level decline, spring drying and 
degradation, or the loss of aquatic habitat (Zektser et al. 2005, pp. 
396-397).
    The Nevada State Engineer (NSE) approves and permits groundwater 
rights in Nevada and defines perennial yield as ``The amount of usable 
water of a groundwater reservoir that can be withdrawn and consumed 
economically each year for an indefinite period of time. It cannot 
exceed the sum of the Natural Recharge, the Artificial (or Induced) 
Recharge, and the Incidental Recharge without causing depletion of the 
groundwater reservoir'' (Nevada Division of Water Planning (NDWP) 
undated, p. 236). The NSE estimates perennial yield for 256 basins and 
sub-basins (areas) in Nevada, and may ``designate'' a groundwater 
basin, meaning the basin's ``* * * permitted ground water rights 
approach or exceed the estimated average annual recharge and the water 
resources are being depleted or require additional administration'' 
(NDWP undated, p. 81). In the interest of public welfare, the NSE may 
declare preferred uses (such as municipal water supply, irrigation, or 
minimum stream flows) within such basins (NDWP, undated, pp. 81-82). 
Table 2 shows the perennial yield and committed groundwater rights for 
selected basins in Nevada applicable to this finding (Southern Nevada 
Water Authority (SNWA), in litt. 2011, p. 4).

[[Page 54297]]



 Table 2--Perennial Yield and Committed Groundwater Rights for Selected
              Basins in Nevada (SNWA, in litt. 2011, p. 4)
------------------------------------------------------------------------
                                                          Committed
                               Perennial yield in    groundwater rights
      Hydrographic area          acre-feet/year       in acre-feet/year
                               (cubic meters/year)  (cubic  meters/year)
------------------------------------------------------------------------
Cave Valley.................  5,000-13,700          47-51 (57,974-
                               (6,167,409-16,898,7   62,908)
                               01).
Lake Valley.................  12,000 (14,801,782).  17,062 (21,045,667)
Spring Valley...............  80,000-94,800         21,702-22,507
                               (98,678,548-116,934   (26,769,023-27,761,
                               ,080).                976)
Steptoe Valley..............  70,000 (86,343,730).  114,144
                                                     (140,794,553)
White River Valley..........  37,000 (45,638,829).  33,077 (40,799,879)
------------------------------------------------------------------------

    The petition and others suggest that water development may impact 
the White River Valley skipper (Austin et al., in litt. 2000, p. 4; 
NatureServe 2009a, p. 2; WildEarth Guardians 2010, pp. 38-40). Lowering 
of the groundwater table could impact the White River Valley skipper by 
adversely impacting Juncus mexicanus, the apparent host plant for this 
subspecies. This plant species grows in moist habitats such as wetlands 
(Reed 1988, pp. 8, 10; Austin and Leary 2008, p. 11).
    The NNHP estimates that approximately 50 percent of the springs and 
brooks in both the upper White River (which includes Ruppes Place/
Boghole, where the subspecies has been located) and lower White River 
(which includes Sunnyside, where the subspecies has been located) has 
been eliminated, converted to other land uses, or degraded due to 
various activities including water development (NNHP 2007, p. 44). The 
NNHP estimates that approximately 60 percent of wetlands, springs, and 
brooks in Big Smoky Valley (where the subspecies has been observed) has 
been eliminated, converted to other land uses, or degraded by various 
activities including water development (NNHP 2007, p. 35). However, the 
NNHP (2007) does not delineate these areas on a map or define them in 
terms of acreage; therefore, the amount of White River Valley skipper 
habitat or the total number of occupied sites (made difficult because 
locations where the skipper has been seen are not specific) that may 
occur within these broad, vague areas and may be impacted by the 
various activities are not documented. The extent to which the various 
land use practices have degraded or converted these areas is also not 
individually delineated or quantified by NNHP (2007). Therefore, we are 
not able to determine the amount of overlap between the estimated 
wetland impacts identified by the NNHP and the distribution of the 
White River Valley skipper.
    The White River Valley and Lake Valley hydrographic areas are 
``designated'' basins by the NSE and permitted groundwater rights 
approach or exceed the estimated average annual recharge of the basin 
(Table 2; Nevada Department of Conservation and Natural Resources Web 
site accessed at http://dcnr.nv.gov on May 15 and July 24, 2012). As a 
``designated'' basin, the NSE has authority under NRS Sec.  534.120 to 
establish additional rules, regulations, or orders to protect that 
basin's water resources (SNWA, in litt. 2011, p. 41). If such 
additional rules, regulations, or orders are established in the future, 
they may also provide some protection to species dependent on these 
water resources, such as the White River Valley skipper. The NSE can 
declare preferred uses (such as domestic, municipal, industrial, 
irrigation, or other uses) in a designated groundwater basin. To date, 
neither the White River Valley nor Lake Valley hydrographic area has 
preferred uses identified.
    Specifically, the petition identifies the Southern Nevada Water 
Authority (SNWA) proposed groundwater pumping project in central 
eastern Nevada as a threat to the White River Valley skipper and other 
butterflies (WildEarth Guardians 2010, p. 39). The following 
information on the SNWA groundwater pumping project is also relevant to 
and incorporated by this reference into the discussions of the Steptoe 
Valley crescentspot and the Baking Powder Flat blue butterfly later in 
this document.
    The proposed Clark, Lincoln, and White Pine Counties Groundwater 
Development Project Draft Environmental Impact Statement (EIS) (BLM 
2011a) addresses SNWA's proposed project to construct and operate a 
system of groundwater conveyance facilities, including pipelines, 
pumping stations, power lines, a substation, pressure reduction 
stations, an underground reservoir, a treatment plant, and associated 
ancillary facilities to import up to 176,655 acre-feet/year (afy) 
(217,900,737 cubic meters/year (m\3\y)) from central eastern Nevada 
(Lincoln and White Pine Counties) to Las Vegas Valley (Clark County) 
(BLM 2011a, pp. 1-2; Executive Summary (ES)-1).
    Valleys that may be affected by the project's groundwater drawdowns 
and that may also support three of the four petitioned subspecies, 
including the White River Valley Skipper, are Cave Valley, Lake Valley, 
Spring Valley, Steptoe Valley, and White River Valley. Currently, some 
specific features of the proposed project are known (e.g., main 
pipeline and associated facilities (power transmission, pump stations)) 
(BLM 2011a, p. 2-5). Locations of future facilities for groundwater 
development including number and location of wells, routes and lengths 
of collector pipelines, distribution lines, and access roads are not 
yet known (BLM 2011a, p. 2-5). The impacts of future facility 
development and groundwater withdrawal, which is analyzed conceptually 
in BLM's draft EIS, will be specifically addressed in subsequent 
National Environmental Policy Act (NEPA) analyses (BLM 2011a, p. 2-5).
    This project is also contingent on the approval of SNWA's water 
rights applications by the NSE (BLM 2011a, p. ES-14). On March 22, 
2012, the NSE issued four rulings on SNWA's water right applications 
for their proposed project totaling up to approximately 84,000 afy 
(103,612,476 m\3\y) (Nevada Department of Conservation and Natural 
Resources Web site accessed at http://dcnr.nv.gov on April 12, 2012); 
this amount is a reduction from SNWA's recent request of approximately 
105,000 afy (129,515,595 m\3\y). These four rulings are for Spring, 
Cave, Dry Lake, and Delamar Valleys. Each of these applications is 
subject to a minimum of 2 years of biological and hydrological data 
collection prior to exportation; a hydrological monitoring, mitigation, 
and management program; a biological monitoring plan, and a computer 
groundwater flow model that must be updated to assist in predicting 
impacts. If unanticipated impacts to existing water rights, conflicts 
with existing domestic wells, or pumping is harmful to the public 
interest or is not environmentally sound, SNWA would

[[Page 54298]]

be required to take measures to mitigate the impacts which could 
include pumping curtailment. The proposed project's main pipeline is 
scheduled for phased construction from 2013 to 2023 (BLM 2011a, pp. ES-
14-ES-15, ES-19). The entire project is scheduled to be constructed and 
operational by approximately 2050 (BLM 2011a, p. 2-30).
    Determining whether groundwater development is a threat to springs, 
streams, or wetlands and therefore a potential threat to those 
petitioned subspecies whose habitats are associated with moist areas 
depends upon whether: (1) The basins in which withdrawals are occurring 
or proposed exceed perennial yield or have a hydrologic connection to 
springs and groundwater flow systems; (2) the springs, streams, or 
wetlands are upgradient and outside of the zone of influence of the 
carbonate aquifer (i.e., they occur in the alluvial aquifer or mountain 
block aquifer instead); or (3) the springs, streams, or wetlands are 
too far away from proposed pumping to be impacted (Welch et al. 2007, 
pp. 71-79). Simply comparing permitted groundwater or surface water 
rights to the perennial yield of a hydrographic area is inadequate to 
determine if a site or biotic entity will be impacted as additional 
factors should be considered as indicated above (SNWA, in litt. 2011, 
p. 5). There needs to be hydraulic connectivity between groundwater 
pumping and the site. If there is no hydraulic connectivity, a site 
will not be impacted. A site may only be lightly impacted if the 
distance is great or the transmissivity is low.
    Hydraulic connectivity is influenced by hydrogeologic conditions 
(groundwater flow systems, groundwater flow paths, flow direction, flow 
barriers, etc.) (SNWA, in litt. 2011, p. 5). Comparing the amount of 
permitted groundwater rights to a basin's estimated recharge or 
perennial yield does not indicate that pumping exceeds the recharge or 
that resources are being threatened (SNWA, in litt. 2011, p. 5). Permit 
holders may not pump their entire amount due to self-imposed 
restrictions, agreements, or permit requirements (SNWA, in litt. 2011, 
p. 5). The manner and purpose of the water right use can also influence 
potential impacts from groundwater or surface withdrawal (SNWA, in 
litt. 2011, p. 6). A permit for agricultural use will not consume the 
entire amount since a portion is returned to the groundwater system 
through irrigation itself or through the inefficiency of the conveyance 
system (SNWA, in litt. 2011, p. 6). Management of groundwater 
development, monitoring, and conservation and mitigation measures can 
reduce impacts of water withdrawal to a site and species (SNWA 2011, p. 
6).
    Groundwater flow modeling efforts for SNWA's proposed project are 
described in BLM's draft EIS (BLM 2011a, pp. 3.3-80-3.3-85), as well as 
the uncertainties and limitations expected with regional groundwater 
flow models that cover a large area with complex hydrogeologic 
conditions (BLM 2011a, pp. 3.3-85-3.3-87). While the model is a 
reasonable tool for regional-scale drawdown trends (BLM 2011a, p. 3.3-
86), it is not an accurate predictor for site-specific changes in flow 
for streams or springs (BLM 2011a, p. 3.3-87).
    Two stipulations related to SNWA's proposed project were reached 
between SNWA and four Department of the Interior bureaus (the Service, 
the Bureau of Indian Affairs (BIA), the BLM, and the National Park 
Service (NPS)) in 2006 and 2008 (SNWA, in litt. 2011, p. 8). The goals 
of the Spring Valley Stipulation (BIA et al. 2006, p. 4) are to (1) 
manage SNWA groundwater development in Spring Valley to avoid 
unreasonable adverse effects to groundwater-influenced ecosystems 
(e.g., springs) and maintain the biological integrity and ecological 
health of the area of interest over the long-term, and (2) avoid 
effects to groundwater-influenced ecosystems within the boundary of 
Great Basin National Park. The goals of the Delamar Valley, Dry Lake 
Valley, and Cave Valley (DDC) Stipulation (BIA et al. 2008, Exhibit A, 
p. 2) are to manage the development of groundwater by SNWA in Delamar 
Valley, Dry Lake Valley, and Cave Valley hydrographic areas without 
causing (1) injury to Federal water rights and (2) any unreasonable 
adverse effects to Federal resources and special status species within 
the area of interest as a result of groundwater withdrawals in those 
basins by SNWA; and (3) to take actions that protect and recover 
special status species that are currently listed pursuant to the Act 
and that avoid listing of currently non-listed special-status species. 
Both stipulations have a list of requirements related to management, 
creation of technical and management teams, a consensus-based 
decisionmaking process, and monitoring and mitigation which, if the 
SNWA project is constructed, will benefit and avoid and minimize 
threats relevant to the White River Valley skipper, Steptoe Valley 
crescentspot, and the Baking Powder Flat blue butterfly (SNWA, in litt. 
2011, pp. 8-10).
    In addition to the two stipulations, an Adaptive Management Plan 
has been prepared by SNWA for its proposed project. It includes a list 
of measures that can be implemented based on the environmental resource 
impacted, the severity, and likely cause(s) (BLM 2011a, Appendix E, 
Appendix A, pp. A-46-A-57). The Adaptive Management Plan acknowledges 
the uncertainties in predicting effects of groundwater withdrawal on 
hydrologic flow systems. The plan will identify and implement 
practicable adaptive management measures to address adverse 
environmental impacts relevant to the three butterfly and skipper 
subspecies including avoiding, minimizing, or mitigating: (1) Adverse 
environmental impacts to groundwater-dependent ecosystems and their 
biological communities, (2) effects of actions that could contribute to 
listing of species under the Act, and (3) adverse environmental impacts 
to water features that support fish and wildlife species. Specific 
actions to be implemented would be determined at a later date based on 
data collection and monitoring results.
    The proposed project construction and operation may impact White 
River Valley skipper habitat (BLM 2011a, p. 3.6-27). The White River 
Valley skipper was not detected in the project's ROW surveys of 
groundwater development areas (BLM 2011a, pp. 3.6-18-3.6-19; 3.6-94). 
Based on the groundwater flow model estimate for 200 years post full 
buildout, the skipper's occupied areas at Ruppes Place/Boghole (SNWA, 
in litt. 2011, p. 17) and areas at the Flag Springs Complex/Sunnyside/
Kirch Wildlife Management Area (SNWA, in litt. 2011, p. 19) are located 
outside of the greater than 10-foot (3.0-m) drawdown contour (or any 
other contour range) (BLM 2011a, p. 3.3-102). However, based on the 
model estimate, there is a potential 17 percent flow decrease at 200-
years post full buildout at Flag Springs 3 (BLM 2011a, p. 3.3-108). The 
Flag Springs Complex and Sunnyside Creek are biological monitoring 
sites under the DDC Stipulation and are hydrologic monitoring sites 
under the Hydrologic Monitoring and Mitigation Plan for Delamar, Dry 
Lake, and Cave Valleys (Exhibit A of the DDC Stipulation (BIA et al. 
2008,)) (SNWA, in litt. 2011, p. 19), which would be monitored for 
early signs of impacts to these areas with mitigating measures 
available to reduce adverse impacts to the area and thus to the White 
River Valley skipper. While the Service recognizes that uncertainties 
remain regarding potential impacts to water resources, all but one 
location occupied by White River Valley skipper

[[Page 54299]]

occur outside of the estimated drawdown contour in the White River 
Valley.
    Based on the groundwater flow model estimate for 200 years post 
full buildout (BLM 2011a, p. 3.3-102), an unknown portion of this 
skipper's occupied habitat is located within the greater than 10-foot 
(3.0-m) drawdown contour and could be impacted at Blind Spring in 
Spring Valley. Because its apparent larval host plant, Juncus 
mexicanus, is a wetland species, habitat for the White River Valley 
skipper could be affected by the SNWA water development project (BLM 
2011a, p. 3.6-74). Though monitoring is occurring using surface-water 
gages, groundwater monitoring wells, and a piezometer on or near Cleve 
Creek (Spring Valley), possible future project impacts to White River 
Valley skipper in Spring Valley are unclear (SNWA, in litt. 2011, p. 
20). As indicated earlier, there is uncertainty whether the White River 
Valley skipper is actually found in Spring Valley (Austin and McGuire 
1998, pp. 778-779).
    Based on the recent water right application rulings issued by the 
NSE for reduced pumping amounts in Spring Valley (Nevada Department of 
Conservation and Natural Resources Web site accessed at http://dcnr.nv.gov on April 12, 2012), it appears that potential impacts at 
Blind Spring would be reduced. Additionally, these recent rulings 
require that the pumping in Spring Valley occur in stages with an 
initial pumping of 38,000 afy (46,872,311.0 m\3\y) for 8 years and the 
full amount of approximately 61,000 afy (75,242,393.2 m\3\y) being 
pumped only if previous stages indicate it is appropriate based on data 
collection and management plans indicated above (biological and 
hydrological data collection; hydrological monitoring, mitigation, and 
management program; biological monitoring plan, and a computer 
groundwater flow model) (Nevada Department of Conservation and Natural 
Resources Web site accessed at http://dcnr.nv.gov on April 12, 2012).
    Lake Valley is also shown to be impacted by pumping (BLM 2011a, p. 
3.3-102; SNWA, in litt. 2011, pp. 20-21), but as described in the 
Distribution and Habitat section, there is uncertainty whether the 
White River Valley skipper occurs in Lake Valley (Austin and McGuire 
1998, pp. 778-779). Without specific locations indicated for specimens 
collected in Lake Valley, it is difficult to determine possible impacts 
to this subspecies from SNWA's proposed project in this valley. We 
conclude that SNWA's proposed groundwater development project would not 
impact populations of this subspecies in Big Smoky Valley as these 
populations occur too far west of the proposed project area and occur 
outside of the area(s) that would be affected by the groundwater 
project.
    While human water demands have impacted wetland areas in the White 
River and Big Smoky Valleys, the White River Valley skipper is rather 
widespread throughout its known distribution in these valleys. Other 
locations (Spring Valley and Lake Valley) where the subspecies may be 
found are tentative locations based on Austin and McGuire (1998, pp. 
778-779). The possible host plant for the White River Valley skipper, 
Juncus mexicanus, has not been confirmed as the host plant at any 
location where the skipper has been observed (Austin and Leary 2008, p. 
11). Because of these uncertainties related to some of the subspecies' 
reported locations as well as its host plant, overall potential impacts 
due to SNWA's proposed project are difficult to determine. However, 
based on the possible impact to only one occupied White River Valley 
skipper location (Flag Springs 3), the recent water right application 
rulings issued by the NSE for reduced pumping amounts in Spring Valley 
and the presumed reduction in potential impacts at Blind Spring as well 
as the initial staged pumping in Spring Valley (Nevada Department of 
Conservation and Natural Resources Web site accessed at http://dcnr.nv.gov on April 12, 2012), we do not anticipate major impacts to 
the White River Valley skipper from SNWA's proposed project.
    In addition, the SNWA water project has multiple design features 
developed to reduce adverse effects to groundwater-influenced 
ecosystems. The Spring Valley Stipulation (BIA et al. 2006, Exhibit A, 
p. 10), which was negotiated between SNWA, the Service, BIA, BLM, and 
the NPS, requires an adaptive management approach in implementation of 
the water development project, monitoring, mitigation (may include 
geographic redistribution, reduction, or cessations in groundwater 
withdrawals; provision of consumptive water supply requirements using 
surface and groundwater sources; augmentation of water supply for 
Federal water rights and resources using surface and groundwater 
sources; and other measures agreed to by the parties or the NSE 
consistent with the stipulation), creation of technical and management 
teams, and a consensus-based decisionmaking process. These project 
design features will likely result in reduced potential effects of the 
project on habitat suitability for the White River Valley skipper.
    While water development has occurred in parts of the White River 
Valley skipper's range (White River Valley and Big Smoky Valley), we 
found no information indicating effects from past water development 
have resulted in loss or degradation of White River Valley skipper 
habitat. The SNWA water project could affect groundwater flow in 
certain parts of the White River Valley skipper's known and possible 
range (White River Valley, Spring Valley, and Lake Valley), but not in 
other parts of its range (Big Smoky Valley). The SNWA water project 
also has multiple design features developed to reduce adverse effects 
to groundwater-influenced ecosystems. At this time, the best available 
information does not indicate that water development is modifying the 
White River Valley skipper's habitat to the extent that it represents a 
threat to this subspecies now or in the future.
Land Development
    Different levels of development can greatly alter the amount of 
larval host plants and adult nectar sources for butterflies, affecting 
directly the distribution and abundance of individual species and 
indirectly the microclimate (Blair and Launer 1997, p. 119). Blair and 
Launer (1997, p. 116) found the abundance of the 23 butterfly species 
included in their California study varied across the development 
gradient from natural to urban. The butterfly community contained fewer 
species in more developed sites compared to the relatively undeveloped 
oak-woodland community (Blair and Launer 1997, p. 117). Species 
richness and diversity was greatest at moderately disturbed sites while 
the relative abundance decreased from the natural to the urban areas 
(Blair and Launer 1997, p. 113).
    Bock et al. (2007, pp. 40-41) found that low-density housing 
developments in former ranch lands of Arizona impacted butterfly 
species abundance and variety to a lesser degree than in developed 
urban or suburban landscapes as documented elsewhere by others. 
Summerville and Crist (2001) studied the effects of habitat 
fragmentation on patch use by butterflies and skippers. They found that 
butterflies and skippers select habitat based on quantity (size) and 
quality (flower availability); moderately-sized patches of high quality 
may function equally to larger patches of lower quality (Summerville 
and Crist 2001, p. 1367). Species did not respond

[[Page 54300]]

equally to fragmentation, with rare species no longer using patches 
where less than 40 percent of the habitat remained (Summerville and 
Crist 2001, p. 1365). While some common species appeared unaffected by 
fragmentation, other common species were significantly affected 
(Summerville and Crist 2001, p. 1365).
    The petition suggests that land development may impact this 
subspecies (WildEarth Guardians 2010, pp. 38-40). A portion of the 
springs and wetlands in the upper and lower White River and Big Smoky 
Valleys have been eliminated, converted, or degraded due to land uses, 
such as land development (NNHP 2007, pp. 35, 44). The NNHP (2007) does 
not delineate these areas in terms of location, acreage, or by land use 
practice. Although the White River Valley skipper is known to occur in 
several locations within these valleys, the number of sites or the 
amount of White River Valley skipper habitat that may be impacted by 
land development is not documented.
    The best available information does not indicate that land 
development is occurring in habitat that is occupied by the White River 
Valley skipper. We did not receive any information as a result of our 
90-day petition finding notice, nor did we locate information 
indicating that land development is negatively impacting the habitat or 
the known populations of the White River Valley skipper. Therefore, the 
best available information does not indicate that land development is 
modifying the subspecies' habitat to the extent that it represents a 
threat to this subspecies now or in the future.
Livestock Grazing
    Potential impacts of livestock grazing include selective grazing 
for native plant species and reducing cover, trampling of plants and 
soil, damage to soil crusts, reduction of mycorrhizal fungi, increases 
in soil nitrogen, increases in erosion and runoff, increases in fire 
frequency, and contribution to nonnative plant introductions (Fleishner 
1994, pp. 631-635; Belsky et al. 1999, pp. 8-11; Paige and Ritter 1999, 
pp. 7-8; Belsky and Gelbard 2000, pp. 12-18; Sada et al. 2001, p. 15).
    In relation to butterflies, as noted in the petition, livestock 
grazing can impact host plants as well as nectar sources, trample 
larvae and the host or nectar plants, degrade habitats, and assist in 
the spread of nonnative plant species that can dominate or replace 
native plant communities and thereby impact larval host and adult 
nectar species (WildEarth Guardians 2010, pp. 22-23). While the 
petition states that light or moderate grazing can assist in 
maintaining butterfly habitats (WildEarth Guardians 2010, p. 23), heavy 
grazing is considered incompatible with the conservation of some 
butterflies (Sanford 2006, p. 401; Selby 2007, pp. 3, 29, 33, 35).
    Kruess and Tscharntke (2002, p. 1570) found an increase of species 
richness and abundance from pastures to ungrazed grasslands in Germany 
for grasshoppers, butterflies, bees, and wasps. Decreased grazing on 
pastures resulted in increased species richness and abundance for adult 
butterflies. Vogel et al. (2007, p. 78) evaluated three restoration 
practices in prairie habitat in Iowa on butterfly communities and found 
that the total butterfly abundance was highest in areas restored 
through burning and grazing, and was lowest in areas that were only 
burned. Species richness did not differ among the practices. Species 
diversity was highest in areas that were only burned. Individual 
butterfly species responses to the restoration practices were variable.
    BLM regulatory authority for grazing management is provided at 43 
CFR part 4100 (Regulations on Grazing Administration Exclusive of 
Alaska). Livestock grazing permits and leases contain terms and 
conditions determined by BLM to be appropriate to achieve management 
and resource condition objectives on the public lands and other lands 
administered by the BLM, and to ensure that habitats are, or are making 
significant progress toward, being restored or maintained for BLM 
special status species (43 CFR 4180.1(d)). Grazing practices and 
activities include the development of grazing-related portions of 
implementation or activity plans, establishment of terms and conditions 
of permits, leases, and other grazing authorizations, and range 
improvement activities such as vegetation manipulation, fence 
construction, and development of water for livestock.
    BLM grazing administration standards for a particular state or 
region must address habitat for endangered, threatened, proposed, 
candidate, or special status species, and habitat quality for native 
plant and animal populations and communities (43 CFR 4180.2(d)(4) and 
(5)). The guidelines must address restoring, maintaining, or enhancing 
habitats of BLM special status species to promote their conservation, 
and maintaining or promoting the physical and biological conditions to 
sustain native populations and communities (43 CFR 4180.2(e)(9) and 
(10)).
    The petition and others suggest that livestock grazing may impact 
this subspecies (NatureServe 2009a, p. 2; WildEarth Guardians 2010, pp. 
38-40), but specific information supporting this claim is not provided. 
A portion of the springs and wetlands in the upper and lower White 
River and Big Smoky Valleys have been eliminated, converted, or 
degraded due to other land uses, such as livestock grazing (NNHP 2007, 
pp. 35, 44). The NNHP (2007) does not delineate these areas in terms of 
location, acreage, or by land use practice. The type locality (1 mi 
(1.6 km) north of the Nye County line) is on private and BLM lands. It 
is not known how livestock grazing is managed on the private lands, but 
general knowledge of the area indicates it is not heavily grazed during 
the late spring to early summer period (Lowrie in litt. 2012, p. 1). 
The Ruppes/Boghole location is on private and BLM lands. It is not 
known how grazing is managed on the private lands, but the area has 
been grazed in the past (Lowrie in litt. 2012, p. 7), and the site 
appears to continue to provide suitable habitat for the skipper (Lowrie 
in litt. 2012, p. 7).
    The type locality and the Ruppes/Boghole sites are surrounded by 
three BLM grazing allotments (Dee Gee Spring to the east, North Cove to 
the west; and Swamp Cedar to the northwest) (Lowrie in litt. 2012, p. 
1), which may support limited suitable habitat (Lowrie in litt. 2012, 
pp. 5-6). The allotments are permitted for cattle grazing during the 
late winter to early summer, though none are grazed the entire period 
(Lowrie in litt. 2012, pp. 1-3). The animal unit months have generally 
been reduced since 1999 for all three allotments; each allotment has 
received growing season rest in various years since 1999 (Lowrie in 
litt. 2012, pp. 3-5).
    The Kirch WMA encompasses about 14,800 ac (5,989 ha) of public 
State lands with five major reservoirs (www.NDOW.org, p. 6; accessed 
April 27, 2012). Based on observations in 2005 when the White River 
Valley skipper was observed on the WMA, Boyd (pers. comm. 2012b, p. 1) 
thought grazing by feral horses may have occurred at the south end of 
Tule Reservoir. The area is primarily a recreational area with limited 
fishing, hunting, camping, and OHV use during certain times.
    The presumed larval host plant, Juncus mexicanus, is common and can 
be found in several Nevada counties in moist habitats. The adults 
likely feed on a variety of plants flowering during their flight 
period. The best available information does not indicate declines in 
larval or adult plant species in

[[Page 54301]]

occupied White River Valley skipper habitat due to livestock grazing. 
Activities involving grazing management within any suitable White River 
Valley skipper habitat on BLM lands are addressed in consideration of 
the Ely District Record of Decision and Approved Resource Management 
Plan (RMP) (BLM 2008a) (see Factor D discussion under White River 
Valley skipper), BLM's authority under Regulations on Grazing 
Administration Exclusive of Alaska, BLM's 6840 Manual (BLM 2008b) (see 
Factor D discussion under White River Valley skipper), and possibly 
NEPA.
    We did not receive any additional information as a result of our 
90-day petition finding notice, nor did we locate information 
indicating that livestock grazing is negatively impacting the habitat 
or White River Valley skipper populations. Thus, the best available 
information does not indicate that livestock grazing is modifying the 
subspecies' habitat to the extent that it represents a threat to this 
subspecies now or in the future.
Nonnative Plant Invasion
    Nonnative species can present a range of threats to native 
ecosystems, including extinction of native species, alteration of 
ecosystem functions, and introduction of infectious diseases 
(Schlaepfer et al. 2011, p. 429). However, not all nonnative species 
cause economic or biological harm and only a small percentage become 
established and result in harmful effects (Williamson and Fitter 1996 
and Davis 2009, cited in Schlaepfer et al. 2011, p. 429). Nonnative 
species can provide a conservation value, for example, by providing 
food or habitat for rare species (Schlaepfer et al. 2011, p. 431).
    The introduction of nonnative or invasive plant species or types of 
vegetation (forbs, shrubs, grasses, etc.) can threaten butterfly 
populations because these introduced species may compete with and 
decrease the quantity and quality of larval host plants and adult 
nectar sources (76 FR 12667, March 8, 2011). This competition resulting 
in loss of host plants and nectar sources has been observed with the 
Quino checkerspot butterfly (Euphydryas editha quino) (62 FR 2313, 
January 16, 1997) and Fender's blue butterfly (Icaricia icarioides 
fenderi) (65 FR 3875, January 25, 2000). However, Graves and Shapiro 
(2003, p. 430) found that California butterflies use numerous nonnative 
plant species positively and negatively. Some of them are using these 
nonnative plant species for depositing eggs and feeding, which has led 
to range expansions, increased population size, extension of the 
breeding season as well as the opportunity to remain in an area where 
the native host plant species has been lost. Nonnative plant species 
have also allowed butterfly species from outside the State to invade 
and breed in California. There are also instances where egg laying has 
occurred on a nonnative plant species that is toxic to the larvae.
    There has been an increased focus on the roles that State, county, 
and private entities have in controlling invasive plants. For example, 
the Noxious Weed Control and Eradication Act of 2004 is intended to 
assist eligible weed management entities to control or eradicate 
harmful nonnative weeds on both public and private lands and is an 
amendment to the Plant Protection Act of 2000 (1 U.S.C. 7701 et seq., 
p. 1) which, in part, determined that detection, control, eradication, 
suppression, prevention, and retardation of the spread of noxious weeds 
is necessary to protect the agriculture, environment, and economy in 
the United States. Additionally, Executive Order 13112 was signed on 
February 3, 1999, establishing an interagency National Invasive Species 
Council in charge of creating and implementing a National Invasive 
Species Management Plan. The Management Plan directs Federal efforts, 
including overall strategy and objectives, to prevent, control, and 
minimize invasive species and their impacts (National Invasive Species 
Council 2008, p. 5). However, the Executive Order also directs the 
Council to encourage planning and action at local, tribal, state, 
regional, and ecosystem levels to achieve the goals of the National 
Invasive Species Management Plan, in cooperation with stakeholders 
(e.g., private landowners, states) and existing organizations 
addressing invasive species.
    Noxious and invasive weed treatments on BLM lands involving 
reseeding can occur through the Emergency Stabilization and Burned Area 
Rehabilitation Program, a program available to BLM districts (including 
Ely and Winnemucca Districts) which evaluates conditions following 
wildland fire. Actions can be taken to protect soils, riparian areas, 
cultural resources, as well as to reduce potential invasive plant 
species spread. Invasive plant species control is a management 
objective stated in many RMPs, including the RMPs for Ely and 
Winnemucca Districts.
    BLM commonly uses herbicides on lands to control invasive plant 
species. In 2007, BLM completed a programmatic EIS (BLM 2007a) and 
Record of Decision (BLM 2007b) for vegetation treatments on BLM-
administered lands in the western United States. This program approves 
the use of 4 new herbicides, provides updated analyses of 18 currently 
used herbicides, and identifies herbicides that the BLM will no longer 
use on public lands. Information is unavailable on how frequently the 
programmatic EIS has been used for most states or whether actions 
implemented under this EIS have been effective; and while not 
authorizing any specific on-the-ground actions, it guides the use of 
herbicides for field-level planning. Site-specific NEPA analysis is 
still required at the project level (BLM 2007a, pp. ES-1- ES-2).
    A portion of the springs and wetlands in the upper and lower White 
River and Big Smoky Valleys has been eliminated, converted, or degraded 
due to other land uses, such as nonnative species invasion (NNHP 2007, 
pp. 35, 44). It is likely nonnative and invasive plant species occur to 
some extent because numerous nonnative and invasive plant species occur 
in Nevada, though this has not been quantified within the habitat of 
the White River Valley skipper. The White River Valley skipper is 
possibly associated with Juncus mexicanus as its larval host plant 
which is common in the White River Valley and other moist habitats in 
Nevada. Nonnative plant species do not appear to be competing with 
Juncus mexicanus, causing its decline or the decline of potential adult 
nectar plants.
    Activities involving nonnative plant species management within the 
White River Valley skipper habitat on BLM lands would be addressed in 
consideration of the Ely District Record of Decision and Approved RMP 
(BLM 2008a), BLM's authority under Regulations on Grazing 
Administration Exclusive of Alaska, the Plant Protection Act of 2000, 
BLM's programmatic EIS for vegetation treatments on BLM's administered 
lands in the western United States (BLM 2007a), BLM's 6840 Manual (BLM 
2008b), and possibly NEPA (see Factor D). Activities involving 
nonnative plant species management and control on private lands within 
the White River Valley habitat could also be addressed in consideration 
of the Plant Protection Act of 2000. We did not receive any information 
as a result of the 90-day petition finding notice, nor did we locate 
information indicating that nonnative plant species in general, or that 
a specific nonnative or invasive plant species, actually occur in and 
are negatively impacting the habitat and

[[Page 54302]]

populations of the White River Valley skipper. Consequently, the best 
available information does not indicate that nonnative plant species 
are modifying the subspecies' habitat to the extent that it represents 
a threat to this subspecies now or in the future.
Agriculture
    Agricultural practices can eliminate suitable habitat, resulting in 
losses of butterfly species. Fleishman et al. (1999, pp. 214-215) 
states that artificial riparian areas such as irrigated croplands 
support fewer butterfly species than native habitats; that most 
butterfly species found in agricultural sites are widespread 
generalists often found in disturbed sites; that less common species, 
as well as those restricted in native larval host plants, are less 
likely to or do not occur in agricultural sites, and though agriculture 
can provide habitat for some butterfly species, these modified habitats 
cannot replace the natural undisturbed riparian ecosystems.
    The petition and others suggest that the White River Valley skipper 
may be impacted by agriculture (NatureServe 2009a, p. 2; WildEarth 
Guardians 2010, pp. 38-40), though specific information is not provided 
to support this claim. A portion of the springs and wetlands in the 
upper and lower White River and Big Smoky Valleys has been eliminated, 
converted, or degraded due to other land uses, including agriculture 
(NNHP 2007, pp. 35, 44). The best available information does not 
indicate that agriculture is occurring in areas that are occupied by 
the White River Valley skipper. We did not receive any information as a 
result of the 90-day petition finding notice, nor did we locate 
information that indicates agriculture is negatively impacting the 
White River Valley skipper populations, host plants, or nectar sources. 
Thus, the best available information does not indicate that agriculture 
is modifying the subspecies' habitat to the extent that it represents a 
threat to this subspecies now or in the future.
Mining and Energy Development
    Possible impacts to butterflies due to mining exploration and 
development, renewable and nonrenewable energy exploration and 
development, as well as associated power line installation include loss 
of habitat, habitat fragmentation, increased dispersal barriers, 
increases in predators, and disturbance due to human presence.
    The Federal Land Policy and Management Act of 1976 (FLPMA) (43 
U.S.C. 1701 et seq.) is the primary Federal law governing most land 
uses on BLM administered lands. Section 102(a)(8) of FLPMA specifically 
recognizes that wildlife and fish resources are included as uses for 
which these lands are to be managed. BLM has management and permitting 
authorities to regulate and condition oil and gas lease permits under 
FLPMA and the Mineral Leasing Act of 1920, as amended (30 U.S.C. 181 et 
seq.). BLM usually incorporates stipulations as a condition of issuing 
leases. The BLM's planning handbook has program-specific guidance for 
fluid materials (including oil and gas) that specifies that RMP 
decision-makers will consider restrictions on areas subject to leasing, 
including closures, and lease stipulations (BLM 2000, Appendix C, p. 
16). The handbook also specifies that all stipulations must have 
waiver, exception, or modification criteria documented in the plan, and 
indicates that the least restrictive constraint to meet the resource 
protection objective should be used (BLM 2000, Appendix C, p. 16).
    There are specific, major power line installation projects in 
eastern Nevada. The Southwest Intertie Project, proposed by Idaho Power 
Company, involves installation of an approximately 520-mi (836.7-km) 
500-kilovolt (kV) transmission line from Shoshone, Idaho, to Las Vegas, 
Nevada (BLM 1993, p. 1; 2008c, p. 1). Though the White River Valley 
skipper is known from the project area, impacts to it from this project 
were not identified (BLM 1993, pp. 3-75-3-89). The Record of Decision 
approving this action was published in 2008 (BLM 2008c). The One Nevada 
Transmission Line Project, proposed by NV Energy, involves construction 
of a 236-mile (252.3-km) 500-kV transmission line with 
telecommunication and appurtenant facilities, construction and 
expansion of substations, and a loop in the existing Falcon-Gonder 
transmission line in White Pine, Nye, Lincoln, and Clark Counties (BLM 
2010c, p. ES-2). The White River Valley skipper was not observed during 
wildlife surveys conducted for this project (BLM 2010c, Appendix 3D, 
Table 2, pp. 1-5). A Record of Decision approving this project was 
published in 2011 (BLM 2011b).
    A Programmatic EIS for the Designation of Energy Corridors on 
Federal Land in the 11 Western States was published in 2008 (Department 
of Energy (DOE) and BLM 2008). This EIS addresses section 368 of the 
Energy Policy Act of 2005, which directs the designation of corridors 
for oil, gas, and hydrogen pipelines, and electricity transmission and 
distribution facilities on Federal lands. Federal agencies are required 
to conduct environmental reviews to complete the designation and 
incorporate the designated corridors into agency land use and RMPs or 
equivalent plans. This EIS proposes only designation of corridors, and 
no environmental impacts are attributed to this action. Section 368 
does not require agencies to consider or approve specific projects, 
applications for ROW, or other permits within any designated corridor, 
nor does section 368 direct, license, or permit any activity on the 
ground. Any interested applicant would need to apply for a ROW 
authorization, and the agency would consider each application under the 
requirements of various laws and related regulations (DOE and BLM 2008, 
pp. S-1-S-2). The proposed action would designate more than 6,000 mi 
(9,600 km) with an average width of 3,500 ft (1 km) of energy corridors 
across the West (DOE and BLM 2008, p. S-17). Federal land not presently 
in transportation or utility rights-of-way is proposed for use in 
Nevada (373 mi or 600 km) (DOE and BLM 2008, p. S-18). The Record of 
Decision for this action was published in 2009 (BLM 2009b). BLM RMPs 
will be amended as appropriate to address these issues (BLM 2009b, pp. 
31-34).
    The White River Valley skipper may be impacted by mining and energy 
development according to the petition (WildEarth Guardians 2010, p. 
39), though specific information is not provided to support this claim. 
The NNHP indicates that a portion of the springs and wetlands in the 
upper and lower White River and Big Smoky Valleys have been eliminated, 
converted, or degraded due to other land uses, including mining and 
energy development, but these areas were not delineated (NNHP 2007, pp. 
35, 44). Actions involving mineral and energy development within White 
River Valley skipper habitat on BLM-administered lands would be 
addressed in consideration of the Ely District Record of Decision and 
Approved RMP (BLM 2008a), the FLPM A of 1976, the Mineral Leasing Act 
of 1920, BLM's 6840 Manual (BLM 2008b), and NEPA. The best available 
information does not indicate that mining and energy development are 
occurring in occupied White River Valley skipper habitat. We did not 
receive any information as a result of the 90-day petition finding 
notice, nor did we locate information that indicates mining or energy 
development is negatively impacting the subspecies' habitat or White 
River Valley skipper populations. Thus, the best available information 
does not

[[Page 54303]]

indicate that mining and energy development are modifying the 
subspecies' habitat to an extent that they represent a threat to this 
subspecies now or in the future.
Climate Change
    The effects on species and ecosystems due to climate change are 
numerous. For example, there are direct effects due to different 
temperatures on the physiology of an organism (McCarty 2001, p. 321). 
Precipitation amounts directly affect vegetation distribution (McCarty 
2001, p. 321). Climate can also have indirect effects on species 
through the sensitivity of habitats or food supply to temperature and 
precipitation (McCarty 2001, p. 321).
    Climate change is expected to affect the timing and flow of 
streams, springs, and seeps in the Great Basin (Chambers 2008a, p. 20), 
which support the moist meadows upon which some butterflies depend 
(WildEarth Guardians 2010, p. 9). Earlier spring snowmelt appears to be 
affecting the date of blooming for some plants in the Great Basin 
(Chambers 2008b, p. 29). As stated in the petition, potential changes 
in the bloom date of meadow plants due to climate change could affect 
the use of these plants by butterflies (WildEarth Guardians 2010, p. 
9). Drought in the Great Basin could negatively affect riparian 
habitats, moist meadows, and similar habitats, especially those already 
stressed by other factors (Major 1963 cited by West 1983, p. 344). As 
climate changes, droughts may become more common in the Great Basin 
(Chambers et al. 2008, p. 3) and American Southwest (Seager et al. 
2007, pp. 1181-1183), modifying future precipitation (WildEarth 
Guardians 2010, p. 8). Increased carbon dioxide may favor invasion of 
annual grasses such as the nonnative Bromus tectorum (cheatgrass) 
(Smith et al. 2000, pp. 79, 81). Increased temperatures and carbon 
dioxide levels have various effects on plant growth and chemistry, 
which may affect insect abundance and persistence (Stiling 2003, pp. 
486-488). Increasing temperatures can also affect insect development 
and reproduction (Sehnal et al. 2003, pp. 1117-1118).
    The rate at which a species can adapt and change its boundaries may 
be vital to understanding how species will respond to climate change 
(McCarty 2001, p. 327). Studies of groups of species show most are 
responding to climate change; what is also important is to study those 
that do not seem to be responding (McCarty 2001, pp. 327-328). These 
species may be less sensitive to temperature, or they may be unable to 
respond to current moderate increases in temperature (McCarty 2001, p. 
328).
    According to Loarie et al. (2009, p. 1052), species and ecosystems 
will need to shift northward an average of 0.3 mi (0.42 km) per year to 
avoid the effects of increasing temperatures associated with climate 
change. Loarie et al. (2009, p. 1053) also state that distances may be 
greater for species in deserts and xeric (dry habitat) shrublands, 
where climate change is predicted to have greater effect than in some 
other ecosystems. The petition asserts that it is unlikely that small, 
isolated populations of butterflies in the Great Basin, dependent on 
reduced habitats, will be able to shift to other habitats in the face 
of climate change (WildEarth Guardians 2010, p. 9). Many species in the 
Great Basin have specialized habitat requirements and limited mobility, 
which influence their ability to adapt to anthropogenic environmental 
change (Fleishman 2008, p. 61). The petition states that species and 
habitats already stressed by other factors may be less able to cope 
with climate change (WildEarth Guardians 2010, p. 10).
    Certain butterflies have shown an ability to adjust to changing 
climatic conditions. Parmesan (2006, p. 643) reported that butterflies 
frequently show a correlation between spring temperatures and dates of 
first appearance. According to Forister and Shapiro (2003 cited in 
Parmesan 2006, p. 643), 70 percent of 23 species of central California 
butterflies advanced their first flight date by an average of 24 days 
over 31 years. Parmesan (1996, pp. 765-766) showed a range shift for 
Edith's checkerspot butterfly (Euphydryas edithia); this butterfly's 
``population extinctions'' occurred in relation to both latitude and 
elevation showing a shift of extant population locations northward and 
upward.
    The average temperature in the Great Basin has increased 0.6-1.1 
degrees Fahrenheit (0.3-0.6 degrees Celsius) during the last 100 years 
(Chambers 2008b, p. 29) and is expected to increase by 3.6-9.0 degrees 
Fahrenheit (2-5 degrees Celsius) over the next century (Cubashi et al. 
2001, cited Chambers 2008b, p. 29).
    Recent projections of climate change in the Great Basin over the 
next century include: Increased temperatures, with an increased 
frequency of extremely hot days in summer; more variable weather 
patterns and more severe storms; more winter precipitation in the form 
of rain, with potentially little change or decreases in summer 
precipitation; and earlier, more rapid snowmelt (U.S. Environmental 
Protection Agency 1998, pp. 1-4; Chambers and Pellant 2008, pp. 29-33). 
While the petition asserts that climate change may impact this 
subspecies (WildEarth Guardians 2010, pp. 38-40), it is difficult to 
predict local climate change impacts, due to substantial uncertainty in 
trends of hydrological variables, limitations in spatial and temporal 
coverage of monitoring networks, and differences in the spatial scales 
of global climate models and hydrological models (Bates et al. 2008, p. 
3).
    We found no information on how climate change may impact the White 
River Valley skipper's potential host plant, Juncus mexicanus, or adult 
nectar sources. In general, increasing temperatures and drought 
frequency, more winter precipitation in the form of rain, possible 
decreases in summer rain, and earlier, rapid snowmelt could impact the 
host plant by causing physiological stress, altering phenology, 
reducing recruitment events, and reducing seed establishment. However, 
at this time, it is difficult to predict local climate change impacts 
to Juncus mexicanus or to White River Valley skipper's adult nectar 
sources, and how individual plant species will react to climate change. 
Thus, while information indicates that climate change has the potential 
to affect vegetation and habitats used by the White River Valley 
skipper in the Great Basin, there is much uncertainty regarding which 
habitat attributes could be affected, and the timing, magnitude, and 
rate of their change as it relates to this subspecies.
    We did not receive any information as a result of our 90-day 
petition finding notice, nor did we locate specific information that 
indicates climate change is negatively impacting White River Valley 
skipper populations or their habitats. Therefore, the best available 
information does not indicate that climate change is modifying the 
subspecies' habitat to an extent that it represents a threat to this 
subspecies now or in the future.
Summary of Factor A
    While several activities such as water and land development, 
livestock grazing, nonnative species invasion, agriculture, and mining 
and energy development may be impacting a portion of wetland areas in 
White River and Big Smoky Valleys, available information does not 
indicate that these impacts are occurring in occupied White River 
Valley skipper habitat. The available information does not indicate 
that these activities or climate change are negatively impacting White 
River Valley skipper populations. Since the White River Valley skipper 
may be associated with wetland areas, impacts

[[Page 54304]]

from water development could impact the subspecies; however, all but 
one occupied skipper locations are outside the greater than 10-foot 
(3.0-m) drawdown contour for the SNWA proposed project, and major 
impacts are not anticipated for this subspecies in White River Valley. 
Other locations in Spring and Lake Valleys that may support the 
subspecies are located within the greater than 10-foot (3.0-m) drawdown 
contour for the SNWA proposed project but potential impacts from 
groundwater pumping would be reduced due to the recent NSE rulings. 
While information indicates that climate change has the potential to 
affect vegetation used by this subspecies, much uncertainty remains 
regarding which plant attributes may be affected, and the timing, 
magnitude, and rate of their change.
    We conclude based on the best scientific and commercial information 
available that the present or threatened destruction, modification, or 
curtailment of its habitat or range does not currently pose a threat to 
the White River Valley skipper, nor is it likely to become a threat to 
the subspecies in the future.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Rare butterflies and moths are prized by collectors, and an 
international trade exists for insect specimens for both live and 
decorative markets, as well as the specialist trade that supplies 
hobbyists, collectors, and researchers (Morris et al. 1991, pp. 332-
333; Williams 1996, pp. 30-37). The specialist trade differs from both 
the live and decorative market in that it concentrates on rare and 
threatened species (U.S. Department of Justice 1993, pp. 2-3). In 
general, the rarer the species, the more valuable it is (Morris et al. 
1991, p. 333).
    Collecting can be a threat to some butterfly species, such as the 
Fender's blue butterfly (65 FR 3875). Generally, small populations are 
at the highest risk. Overcollecting and repeated handling and marking 
of females for scientific purposes in low abundance years can 
negatively impact populations through loss of reproductive individuals 
and genetic variability (65 FR 3875). Collection of dispersing females 
can also reduce the probability that new colonies will be founded. 
Collectors may serve as a threat because they may not recognize when 
butterfly populations are becoming depleted below a threshold necessary 
for survival or recovery (65 FR 3875).
    We are unaware of any studies analyzing impacts of removal of 
individuals from populations of the White River Valley skipper. 
According to Austin and McGuire (1998, p. 778), 20 males and 14 females 
were collected between 1984 and 1989 at one site. No additional 
information is known about the numbers of specimens collected in the 
past, and we are not aware of any ongoing or current collecting of this 
subspecies. Given the low number of individuals collected over this 6-
year period, the length of time since the collections were made, and 
the lack of information about the relative impact to the populations, 
the available information does not indicate that collection may be a 
threat to this subspecies.
    We found no information indicating that overutilization has led to 
the loss of populations or a significant reduction in numbers of 
individuals for this subspecies. Therefore, we conclude based on the 
best scientific and commercial information available that 
overutilization for commercial, recreational, scientific, or 
educational purposes does not currently pose a threat to the White 
River Valley skipper, nor is it likely to become a threat in the 
future.

Factor C. Disease or Predation

    We found no information on the incidence of disease in the White 
River Valley skipper.
    We assume predation by other species, such as birds or insects, on 
eggs, larvae, pupae, or adult White River Valley skipper occurs, but we 
found no information indicating that predation levels are any greater 
than levels typical of the biological community in which the White 
River Valley skipper occurs.
    Available information does not indicate that there are impacts from 
disease or predation on the White River Valley skipper. Therefore, we 
conclude based on the best scientific and commercial information 
available that disease or predation does not currently pose a threat to 
the White River Valley skipper, nor is either likely to become a threat 
to the subspecies in the future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    This discussion under Factor D applies to all four subspecies and 
is incorporated by this reference into the Factor D discussion for 
Steptoe Valley crescentspot, Baking Powder Flat blue butterfly, and 
bleached sandhill skipper.
    Nevada does not have the ability to protect invertebrates under 
current State law pertaining to wildlife. The Nevada Department of 
Wildlife is limited in its ability to protect insects under current 
regulations (Nevada Revised Statutes (NRS)). Nevada State law protects 
species that the Wildlife Commission determines to be imperiled (NRS 
503.585). While some invertebrates such as mollusks and crustaceans may 
be protected because they can be classified under wildlife (NRS 
501.110), butterflies are not covered under this statute. No butterfly 
or skipper species are currently protected by State law in Nevada 
(Nevada Administrative Code 503.020-503.080). Therefore, no regulatory 
protection is offered under Nevada State law for the White River Valley 
skipper, Steptoe Valley crescentspot, Baking Powder Flat blue 
butterfly, or bleached sandhill skipper. Although not protected by 
State law, the best available information, as discussed in Factor B, 
does not indicate that collection or other forms of overutilization is 
a threat to the White River Valley skipper.
    As discussed earlier under Factor A, the NSE approves and permits 
groundwater rights in Nevada. A basin's perennial yield is considered 
during this process, and the NSE may ``designate'' a groundwater basin 
indicating that the water resources in that basin are being depleted or 
require additional administration. The White River Valley and the Lake 
Valley hydrographic areas are ``designated'' basins, and the NSE has 
authority to establish additional rules, regulations, or orders to 
protect the basin's water resources. These additional rules, 
regulations, or orders, if established in the future, may provide some 
protection to species dependent on these water resources, such as the 
White River Valley skipper. The best available information does not 
indicate that water development is impacting White River Valley skipper 
populations.
    As discussed above, a portion of habitat for the White River Valley 
skipper occurs on lands administered by BLM, a Federal land-management 
agency within the U.S. Department of the Interior. Numerous laws, 
regulations, and policies have been developed to assist the agency in 
management of these lands.
    All Federal agencies are required to adhere to NEPA for projects 
they fund, authorize, or carry out. The Council on Environmental 
Quality's regulations for implementing NEPA (40 CFR 1500-1518) state 
that agencies shall include a discussion on the environmental impacts 
of the various project alternatives, any adverse environmental effects 
which cannot be avoided, and any irreversible or irretrievable 
commitments of resources involved (40 CFR 1502). Additionally, 
activities on non-Federal lands are subject to NEPA

[[Page 54305]]

if there is a Federal nexus. NEPA is a disclosure law and does not 
require subsequent minimization or mitigation measures by the Federal 
agency involved. Although Federal agencies may include conservation 
measures for sensitive species as a result of the NEPA process, any 
such measures are typically voluntary in nature and are not required by 
the statute.
    BLM's RMPs are the basis for all actions and authorizations 
involving BLM-administered land and resources. They establish allowable 
resource uses; resource conditions, goals, and objectives to be 
attained; program constraints and general management practices needed 
to attain the goals and objectives; general implementation sequences; 
and intervals and standards for monitoring and evaluating each plan to 
determine its effectiveness and the need for amendment or revision (43 
CFR 1601.0-5(k)).
    RMPs provide a framework and programmatic guidance for site-
specific activity plans. These plans address livestock grazing, oil and 
gas field development, travel management (managing vehicle routes and 
access), wildlife habitat management, and other activities. Actions 
potentially affecting the White River Valley skipper, as well as the 
Steptoe Valley skipper and Baking Powder Flat blue butterfly, would be 
addressed under the Ely District Record of Decision and Approved RMP 
(BLM 2008a); actions potentially affecting the bleached sandhill 
skipper would be addressed under the Winnemucca District RMP and EIS 
(BLM 2010a). Activity plan decisions normally also require NEPA (42 
U.S.C. 4321 et seq.) analysis.
    BLM policy and guidance for species of concern occurring on BLM-
administered land is addressed under BLM's 6840 Manual ``Special Status 
Species Management'' (BLM 2008b). This manual provides agency policy 
and guidance for the conservation of special status plants and animals 
and the ecosystems on which they depend, but it is not a regulatory 
document. The objectives for BLM special status species are ``to 
conserve and/or recover ESA-listed species and the ecosystems on which 
they depend so that ESA protections are no longer needed for these 
species and to initiate proactive conservation measures that reduce or 
eliminate threats to Bureau sensitive species to minimize the 
likelihood of and need for listing of these species under the ESA.'' 
(BLM 2008b, p. 3). All four of the butterfly and skipper subspecies 
addressed in this finding are designated BLM sensitive species (BLM 
2007a, pp. J-6, J-7, J-37).
    BLM also operates under its Regulations on Grazing Administration 
Exclusive of Alaska, codified at 43 CFR part 4100, which include 
requirements that grazing administration standards address habitat for 
special status species and habitat quality for native plant and animal 
populations and communities (43 CFR 4180.2(d)(4) and (5)) that 
livestock grazing permits and leases contain terms and conditions 
determined by BLM to be appropriate to achieve management and resource 
condition objectives on the public lands. See discussion under 
Livestock Grazing, above.
    These BLM policies and guidance address species of concern, actions 
covered by RMPs, and regulatory authority for grazing and oil and gas 
leasing and operating activities. As discussed under Factor A, the best 
available information does not indicate that activities, such as 
livestock grazing, nonnative species control, and mining and energy 
development that are regulated by various policies, guidance, and laws 
on Federal lands, are impacting White River Valley skipper populations. 
We conclude based on the best scientific and commercial information 
available that the inadequacy of existing regulatory mechanisms does 
not currently pose a threat to the White River Valley skipper, nor is 
it likely to become a threat to the subspecies in the future.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Potential other natural or manmade factors that may affect the 
continued existence of the White River Valley skipper are discussed in 
this section and include: (1) Limited range and (2) small population 
size(s).
    A limited range or small population size(s) can be a threat for 
some species that may increase the likelihood of extinction. 
Characteristic butterfly population fluctuations and short generation 
times, combined with small populations, can influence genetic diversity 
and long-term persistence (Britten et al. 2003, pp. 229, 233). Concern 
may arise for butterflies that occur as single populations or in a few 
disjunct populations, and the number of populations may be more 
important than population size when assessing the status of a butterfly 
(Sanford 2006, p. 401). Lack of dispersal corridors or resistance to 
barriers to dispersal may inhibit gene flow between populations, and 
increase the likelihood of extinction (Wilcox and Murphy 1985, pp. 882-
883). The combination of few populations, small ranges, and restricted 
habitats can make a species susceptible to extinction or extirpation 
from portions of its range due to random events such as fire, drought, 
disease, or other occurrences (Shaffer 1987, pp. 71-74; Meffe and 
Carroll 1994, pp. 190-197).
    Limited range and small population numbers or sizes are considered 
in determining whether a natural or anthropogenic threat, or a 
combination of threats, may be affecting a particular subspecies. 
However, in the absence of information identifying chance events, other 
threats, the potential for such chance events to occur in occupied 
habitats, and connecting these threats to a restricted geographic range 
of a subspecies, we generally do not consider chance events, restricted 
geographic range, or rarity by themselves to be threats to a 
subspecies. In addition, butterfly populations are highly dynamic and 
from year to year butterfly distributions can be highly variable (Weiss 
et al. 1997, p. 2); and desert species seem prone to dramatic 
fluctuations in number (Scott 1986, p. 109).
    As indicated earlier, the White River Valley skipper is known from 
the White River Valley in White Pine and Nye Counties and from Big 
Smoky Valley in Nye County. It may also occupy areas in Spring and Lake 
Valleys in White Pine and Lake Valley Counties, respectively. The 
aerial extent of each occupied site or of the subspecies' apparent host 
plant has not been reported. Little information is available related to 
its distribution and numbers of populations, and no information is 
available related to population sizes, loss of populations, if any, or 
population trends for the White River Valley skipper. The best 
available information does not include comprehensive surveys for this 
subspecies, though researchers have recommended these surveys to 
determine if additional populations exist.
    Without data to indicate population trends, it is difficult to 
support claims of adverse impacts to the White River Valley skipper. We 
found no information on connections between chance events and 
population impacts for the White River Valley skipper. Since this 
subspecies is distributed over several populations, potential impacts 
due to stochastic events may be reduced. In the absence of chance 
events connected to known populations, we do not consider small 
population numbers or restricted range by themselves to be threats to 
this subspecies. The best available information does not indicate the 
White River Valley skipper is negatively

[[Page 54306]]

impacted by limited range or small population numbers. We conclude 
based on the best scientific and commercial information available that 
other natural or manmade factors do not currently pose a threat to the 
White River Valley skipper, nor are they likely to become a threat to 
the subspecies in the future.

Synergistic Interactions Between Threat Factors

    We have evaluated individual threats to the White River Valley 
skipper. This subspecies faces potential threats from water 
development, land development, livestock grazing, nonnative plant 
invasion, agriculture, mining and energy development, climate change, 
limited range, and small population size. In considering whether the 
threats to a species may be so great as to warrant listing under the 
Act, we must look beyond the possible impacts of potential threats in 
isolation and consider the potential cumulative impacts of all of the 
threats facing a species.
    In making this finding, we considered whether there may be 
cumulative effects to the White River Valley skipper from the combined 
impacts of the existing stressors such that even if each stressor 
individually does not result in population-level impacts, that 
cumulatively the effects may be significant. We considered whether the 
combined effects of water development, land development, and mining and 
energy development may result in a significant impact to the White 
River Valley skipper because these potential impacts have the potential 
to result in some level of habitat loss. However, we conclude that 
synergistic effects between water development, land development, and 
mining and energy development are unlikely to result in a significant 
overall population impact to the White River Valley skipper because the 
water development activities have been ongoing in the valleys and the 
proposed water development project is not anticipated to cause major 
impacts because only one known occupied White River Valley skipper 
location may be impacted to some unknown extent. Impacts from land 
development and mining and energy development were not found to be 
occurring in the subspecies' habitat.
    While livestock grazing and nonnative plant invasion could impact 
the White River Valley skipper and its habitat, livestock grazing and 
nonnative plant species invasion are not known to be resulting in 
population declines of either host plants or nectar plants in occupied 
locations. We conclude that livestock grazing and nonnative plant 
species invasion combined with potential impacts from water development 
would not be of sufficient severity, frequency, or geographic scope to 
result in significant habitat impacts or cause population-level impacts 
to the White River Valley skipper. Agriculture was not found to occur 
within this subspecies' habitat, and therefore, will not have a 
cumulative impact on the White River Valley skipper.
    Limited range and small population size could make the White River 
Valley skipper more vulnerable to potential threats discussed above. 
However, we cannot conclude that synergistic effects between limited 
range and small population size and other potential threats are 
operative threats to the continued existence of the White River Valley 
skipper given the lack of information on the range and population size 
of this butterfly. There is no information on population size or change 
in population abundance for the White River Valley skipper, and the 
limited information on occurrence (distribution) is insufficient to 
define this skipper's range.
    Synergistic interactions are possible between effects of climate 
change and effects of other potential threats such as water 
development, livestock grazing, and nonnative plant invasion. Increases 
in carbon dioxide and temperature and changes in precipitation are 
likely to affect vegetation, and the White River Valley skipper is 
closely associated with the presence of vegetation. However, it is 
difficult to project how climate change will affect vegetation because 
certain plant species may increase in cover while other species may 
decrease. Uncertainty about how different plant species will respond 
under climate change, combined with uncertainty about how changes in 
plant species composition would affect suitability of White River 
Valley skipper habitat, make projecting possible synergistic effects of 
climate change on the White River Valley skipper too speculative.

Finding for the White River Valley Skipper

    As required by the Act, we considered the five factors in assessing 
whether the White River Valley skipper is an endangered or threatened 
species throughout all of its range. We examined the best scientific 
and commercial information available regarding the past, present, and 
future threats faced by this subspecies.
    Factors potentially affecting the White River Valley skipper, 
including water development, land development, livestock grazing, 
nonnative species invasion, agriculture, mining and energy development, 
or climate change, and limited range and small population size, are 
either limited in scope or lack documentation that they are occurring 
in occupied habitat and adversely impacting the subspecies. Though 
climate change may be affecting the White River Valley skipper and its 
habitats, and effects are likely to increase in the future, available 
information does not support a determination that climate change has or 
will result in a population-level impact to this subspecies. Available 
information does not indicate that overutilization, disease, or 
predation are threats to the White River Valley skipper. The available 
information also does not indicate that existing regulatory mechanisms 
are inadequate to protect the subspecies from potential threats. 
Furthermore, there is no information to suggest that the combined 
factors acting together are a threat to the White River Valley skipper. 
Based on our review of the best scientific and commercial information 
available, we find these potential stressors, either singly or in 
combination with one another, are not threats to the White River Valley 
skipper or its habitat.
    We found no information to indicate that threats are of sufficient 
imminence, intensity, or magnitude such that the White River Valley 
skipper is in danger of extinction (endangered) or likely to become 
endangered within the foreseeable future (threatened), throughout all 
of its range. Therefore, we find that listing the White River Valley 
skipper as an endangered or threatened species is not warranted 
throughout its range.

Significant Portion of the Range

    Having determined that the White River Valley skipper does not meet 
the definition of an endangered or a threatened species, we must next 
consider whether there are any significant portions of the range where 
the White River Valley skipper is in danger of extinction or is likely 
to become endangered in the foreseeable future. The Act defines 
``endangered species'' as any species which is ``in danger of 
extinction throughout all or a significant portion of its range,'' and 
``threatened species'' as any species which is ``likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' 16 U.S.C. 1532(6) and 1532(20). The 
definition of ``species'' is also relevant to this discussion. The Act 
defines ``species'' as follows: ``The term `species' includes any 
subspecies of fish

[[Page 54307]]

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). The phrase ``significant portion of its range'' 
(SPR) is not defined by the statute, and we have never addressed in our 
regulations: (1) The consequences of a determination that a species is 
either endangered or likely to become so throughout a significant 
portion of its range, but not throughout all of its range; or (2) what 
qualifies a portion of a range as ``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountains gray wolf (74 FR 15123, April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the Gunnison's prairie dog (73 FR 6660, February 5, 
2008). The Service had asserted in both of these determinations that, 
under the Act, it had authority, in effect, to protect only some 
members of a ``species,'' as defined by the Act (i.e., species, 
subspecies, or DPS). Both courts ruled that the determinations were 
arbitrary and capricious on the grounds that this approach violated the 
plain and unambiguous language of the Act. The courts concluded that 
reading the SPR language to allow protecting only a portion of a 
species' range is inconsistent with the Act's definition of 
``species.'' The courts concluded that once a determination is made 
that a species (i.e., species, subspecies, or DPS) meets the definition 
of ``endangered species'' or ``threatened species,'' it must be placed 
on the list in its entirety and the Act's protections applied 
consistently to all members of that species throughout its range 
(subject to modification of protections through special rules under 
sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing. Thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be endangered or threatened throughout all 
of its range, or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout an SPR, it, the species, is an ``endangered 
species.'' The same analysis applies to ``threatened species.'' Based 
on this interpretation and supported by existing case law, the 
consequence of finding that a species is endangered or threatened in 
only a significant portion of its range is that the entire species 
shall be listed as endangered or threatened, respectively, and the 
Act's protections shall be applied across the species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the SPR phrase as providing an independent basis for listing is the 
best interpretation of the Act because it is consistent with the 
purposes and the plain meaning of the key definitions of the Act; it 
does not conflict with established past agency practice (i.e., prior to 
the 2007 Solicitor's Opinion), as no consistent, long-term agency 
practice has been established; and it is consistent with the judicial 
opinions that have most closely examined this issue. Having concluded 
that the phrase ``significant portion of its range'' provides an 
independent basis for listing and protecting the entire species, we 
next turn to the meaning of ``significant'' to determine the threshold 
for when such an independent basis for listing exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that, 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether, without that portion, the 
representation, redundancy, or resiliency of the species would be so 
impaired that the species would have an increased vulnerability to 
threats to the point that the overall species would be in danger of 
extinction (i.e., would be ``endangered''). Conversely, we would not 
consider the portion of the range at issue to be ``significant'' if 
there is sufficient resiliency, redundancy, and representation 
elsewhere in the species' range that the species would not be in danger 
of extinction throughout its range if the population in that portion of 
the range in question became extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that, without that portion, 
the species would be in danger of extinction) establishes a threshold 
that is relatively high. On the one hand, given that the consequences 
of finding a species to be endangered or threatened in an SPR would be 
listing the species throughout its entire range, it is important to use 
a threshold for ``significant'' that is robust. It would not be 
meaningful or appropriate to establish a very low threshold whereby a 
portion of the range can be considered ``significant'' even if only a 
negligible increase in extinction risk would result from its loss. 
Because nearly any portion of a species' range can be said to 
contribute some increment to a species'

[[Page 54308]]

viability, use of such a low threshold would require us to impose 
restrictions and expend conservation resources disproportionately to 
conservation benefit: Listing would be rangewide, even if only a 
portion of the range of minor conservation importance to the species is 
imperiled. On the other hand, it would be inappropriate to establish a 
threshold for ``significant'' that is too high. This would be the case 
if the standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the SPR phrase independent meaning, as the 
Ninth Circuit held in Defenders of Wildlife v. Norton, 258 F.3d 1136 
(9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the threshold so high that the phrase ``in a 
significant portion of its range'' loses independent meaning. 
Specifically, we have not set the threshold as high as it was under the 
interpretation presented by the Service in the Defenders litigation. 
Under that interpretation, the portion of the range would have to be so 
important that current imperilment there would mean that the species 
would be currently imperiled everywhere. Under the definition of 
``significant'' used in this finding, the portion of the range need not 
rise to such an exceptionally high level of biological significance. 
(We recognize that if the species is imperiled in a portion that rises 
to that level of biological significance, then we should conclude that 
the species is in fact imperiled throughout all of its range, and that 
we would not need to rely on the SPR language for such a listing.) 
Rather, under this interpretation, we ask whether the species would be 
endangered everywhere without that portion (i.e., if that portion were 
completely extirpated). In other words, the portion of the range need 
not be so important that even the species being in danger of extinction 
in that portion would be sufficient to cause the species in the 
remainder of the range to be endangered; rather, the complete 
extirpation (in a hypothetical future) of the species in that portion 
would be required to cause the species in the remainder of the range to 
be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it might be more efficient for us to address 
the significance question first or the status question first. Thus, if 
we determine that a portion of the range is not ``significant,'' we do 
not need to determine whether the species is endangered or threatened 
there; if we determine that the species is not endangered or threatened 
in a portion of its range, we do not need to determine if that portion 
is ``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the White River Valley skipper to 
determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the subspecies including water 
and land development, livestock grazing, nonnative species invasion, 
agriculture, mining and energy development, climate change, and limited 
range and small population size. On the basis of our review, we found 
no geographic concentration of potential threats either on public or 
private lands to suggest that the White River Valley skipper may be in 
danger of extinction in that portion of its range. We found no area 
within the range of the White River Valley skipper where the potential 
threats are significantly concentrated or substantially greater than in 
other portions of its range. We also found that lost historical range 
does not constitute a significant portion of the range for the White 
River Valley skipper because there is no information indicating that 
there has been a range contraction for this subspecies. Therefore, we 
find factors affecting the subspecies are essentially uniform 
throughout its range, indicating no portion of the skipper's range 
warrants further consideration of possible status as an endangered or 
threatened species under the Act.
    We found no information to indicate that the White River Valley 
skipper is in danger of extinction now, nor is it likely to become 
endangered within the foreseeable future, throughout all or a 
significant portion of its range. Therefore, listing the White River 
Valley skipper as an endangered or threatened species under the Act is 
not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the White River Valley skipper to our Nevada 
Fish and Wildlife Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor the White River Valley 
skipper and encourage its conservation. If an emergency situation 
develops for the White River Valley skipper or any other species, we 
will act to provide immediate protection.

Species Information for the Steptoe Valley Crescentspot

Taxonomy and Species Description

    We accept the characterization of the Steptoe Valley crescentspot 
(Phyciodes cocyta arenacolor) as a valid subspecies based on its 
description by Austin (1998b, p. 577) and recent updated nomenclature 
(NatureServe 2009b, p. 1; A. Warren, pers. comm., cited in WildEarth 
Guardians 2010, p. 34). This subspecies was described by Austin (1998b, 
p. 577) from specimens collected in Steptoe Valley at Warm Springs, 
White Pine County, Nevada. This subspecies is in the Nymphalidae family 
(Austin 1998a, p. 843). Male wingspan ranges from 0.67 to 0.74 in 
(17.0-18.8 mm). The upperside is orange and black. The margin is 
broadly black with a marginal spot. The hindwing has a broad black 
margin. The submargin (on the wing, just inside marginal zone) has a 
series of black dots. The fringes of both wings are dark grayish and 
not distinctly checkered with white. The underside of the forewing is 
paler (yellower) than the upperside. The margin and submargin are 
brownish and interrupted with some yellow areas. The hindwing is 
yellowish. A small brownish patch occurs along the middle of the outer

[[Page 54309]]

margin, which also has a distinct submarginal crescent (Austin 1998b, 
p. 577). Females are slightly larger and range from 0.72 to 0.79 in 
(18.2-20.0 mm). The upperside is a paler orange than the male's with a 
forewing that is cream colored postmedian and creamy-orange on the 
submargin. The black is more extensive than on the male. The hindwing 
is like that of the male but the black is broader, separating the rows 
of dots. The underside of the forewing is like that of the male's but 
the postmedian is pale as on the upperside. The underside of the 
hindwing is whitish (Austin 1998b, p. 577). Please refer to Austin 
(1998b, p. 577) for a more detailed description of this subspecies.

Distribution and Habitat

    Descriptions of locations where the Steptoe Valley crescentspot has 
been found are vague. Austin (1993, pp. 8-9) and others (Austin 1998b, 
p. 577; Austin and Leary 2008, p. 102) found the Steptoe Valley 
crescentspot in the moist flats adjacent to Duck Creek from Warm 
Springs (the type locality (Austin 1998b, p. 577)) south to northwest 
of McGill (in unspecified locations) in Steptoe Valley, White Pine 
County, Nevada. This is a distance of approximately 18 mi (29 km) where 
both private and BLM lands occur along Duck Creek. More specific 
locations include Bassett Lake (private lands) located along Duck Creek 
Slough (Austin 1993, p. 9; NNHP 2010). Occurrences have been reported 
by NNHP (2006, p. 42) at Monte Neva Hot Springs (on private and BLM 
lands) and near McGill (on private and BLM lands), White Pine County, 
Nevada. Monte Neva Hot Springs is located about 1 mi (1.6 km) west of 
Warm Springs and about 1 mi (1.6 km) west of Duck Creek. A population 
may be located near the Ruby Mountains (unspecified locations) (Boyd, 
pers. comm. 2012a, p. 2). The NNHP (2009, p. 7) indicates three Nevada 
occurrences, but the locations are not identified. The size of each 
known occupied site and the extent of this subspecies' host plant, or 
host plant abundance, has not been reported.

Biology

    Adults are known to fly as one brood (Austin 1993, p. 9) during 
early July to mid-August (Austin 1993, p. 9; 1998b, p. 577). Though 
adult nectar sources have not been reported, it is possible that they 
nectar on a variety of plants that are in flower during their flight 
period. Aster ascendens (western aster, longleaf aster), now known as 
Symphyotrichum ascendens (http://en.wikipedia.org Web site accessed 
April 25, 2012), has been documented as a larval host plant (Austin and 
Leary 2008, p. 102). This perennial forb occurs in most counties in 
Nevada, including Elko, Eureka, White Pine, Nye, and Lincoln (http://www.plants.udsa.gov Web site accessed April 24, 2012). It can be found 
throughout the western United States (http://www.plants.udsa.gov Web 
site accessed April 24, 2012). It grows in many habitats including 
meadows and disturbed areas (Hickman 1993, p. 206; http://en.wikipedia.org Web site accessed April 25, 2012).
    There is little biological information available at the subspecies 
level, but some inferences can be made from biological information from 
related species at the species level. Information for the orange 
crescent (Phyciodes cocyta=pascoensis) indicates eggs are pale green 
and are laid in clusters under host plant leaves (Scott 1986, p. 310; 
NatureServe 2009b, p. 1). Larvae eat leaves, and no nests are 
constructed (Scott 1986, p. 311). Adults are local and sip flower 
nectar and mud, and males patrol during the day near host plants in 
valley bottoms seeking females (Scott 1986, p. 311).
    The best available information does not include surveys documenting 
this subspecies' population dynamics, its overall abundance, number or 
size of populations, number of extirpated populations, if any, or 
population trends.

Five-Factor Evaluation for the Steptoe Valley Crescentspot

    Information pertaining to the Steptoe Valley crescentspot in 
relation to the five factors provided in section 4(a)(1) of the Act is 
discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    Potential factors that may affect the habitat or range of the 
Steptoe Valley crescentspot are discussed in this section, including: 
(1) Water development, (2) livestock grazing, (3) nonnative plant 
invasion, (4) agriculture, (5) mining and energy development, and (6) 
climate change.
Water Development
    For general background information on water development, please 
refer to the Water Development section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    Austin (1993, pp. 9-10) and Austin et al. (in litt. 2000, p. 2) 
state that water table changes may impact the Steptoe Valley 
crescentspot; however, specific information is not provided to support 
this claim. Since the Steptoe Valley crescentspot is associated with 
moist flats near wetland areas, potential adverse impacts to aquatic 
habitat could result in adverse impacts to the butterfly's habitat 
(e.g., drying of moist habitat and reductions in larval or nectar plant 
abundance). The NNHP (2007, p. 42) states that various wetland areas in 
Steptoe Valley have been degraded or converted to other land uses, 
including water development (including Bassett Lake--25 percent; Duck 
Creek--30 percent, two of several locations where this subspecies has 
been observed). The NNHP (2007) does not delineate these various areas 
in Steptoe Valley on a map or define them in terms of acreage; 
therefore, the amount of Steptoe Valley crescentspot habitat or the 
total number of occupied sites that may occur (made difficult because 
locations where the skipper has been seen are not specific) within 
these areas and may be impacted are not documented. The extent to which 
the various land use practices have degraded or converted these various 
areas is also not individually delineated or quantified by NNHP (2007). 
Therefore, we cannot determine the amount of overlap between the 
estimated wetland impacts identified by the NNHP and the distribution 
of the Steptoe Valley crescentspot.
    Bassett Lake is a manmade reservoir (about 10 ac (4 ha) in size) 
constructed years ago with water control capabilities (Mabey 2012, 
pers. comm.). The amount of Steptoe Valley crescentspot habitat that 
may have been impacted at the time of construction is unknown, and it 
is unknown whether this subspecies' habitat near Bassett Lake and along 
Duck Creek has been enhanced due to a more consistent water supply 
provided by Bassett Lake and its flow releases. The Monte Neva Hot 
Springs is about 5 to 10 ac (2-4 ha) in size with approximately 250 to 
300 ac (101-121 ha) of associated habitat; the springs are located on 
private land. Water from the hot springs has been diverted for at least 
40 years (NNHP in litt., 2007, p. 2). The amount of habitat used by the 
subspecies in this area is not known.
    The Steptoe Valley hydrographic area is a ``designated'' basin by 
the NSE and permitted groundwater rights approach or exceed the 
estimated average annual recharge of the basin (Table 2). As a 
``designated'' basin, the NSE has authority under NRS Sec.  534.120 to 
establish additional rules, regulations, or orders to protect the 
basin's water resources (SNWA, in litt. 2011, p. 41). If such 
additional rules, regulations, or orders are established, they may also

[[Page 54310]]

provide some protection to species dependent on these water resources, 
such as the Steptoe Valley crescentspot. A preferred use for industrial 
(power generation) has been identified for this basin.
    The petition raises concerns about the effects of the proposed SNWA 
water development project in central eastern Nevada on the Steptoe 
Valley crescentspot (WildEarth Guardians 2010, p. 36). The butterfly 
could be impacted by the proposed project due to its habitat being 
impacted by project construction or operation (BLM 2011a, p. 3.6-27). 
However, the Steptoe Valley crescentspot was not detected during the 
project's ROW surveys (BLM 2011a, pp. 3.6-18-3.6-19). Based on the 
groundwater flow model estimate for 200 years post full buildout (BLM 
2011a, p. 3.3-102), this butterfly's occupied areas are located outside 
of the greater than 10-foot (3.0-m) drawdown contour (or any other 
contour range). While the Service recognizes that uncertainties remain 
regarding potential impacts to water resources from SNWA's project, 
within and outside of the 10-foot (3.0-m) drawdown, there are currently 
no anticipated impacts to the Steptoe Valley crescentspot from SNWA's 
proposed project.
    Human water demands have impacted wetland areas in Steptoe Valley 
over the decades. However, the best available information does not 
indicate that impacts due to water development activities are 
negatively impacting this subspecies. Actions regarding water 
management in Steptoe Valley crescentspot habitat in the future would 
be addressed in consideration of Nevada water law. We did not receive 
any information as a result of our 90-day petition finding notice, nor 
did we locate information indicating that water development, either in 
general or specifically from the SNWA proposed project, is impacting 
the subspecies' habitat. Therefore, the best available information does 
not indicate that water development is modifying the subspecies' 
habitat to an extent that it represents a threat to this subspecies now 
or in the future.
Livestock Grazing
    For general background information on livestock grazing, please 
refer to the Livestock Grazing section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    Austin (1993, pp. 9-10) and Austin et al. (in litt. 2000, p. 2) 
state that overgrazing (including trampling) may impact the Steptoe 
Valley crescentspot; however, specific information is not provided to 
support this claim. The NNHP (2007, p. 42) states that a portion of 
wetland areas in Steptoe Valley have been degraded or converted to 
other land uses, including livestock grazing. A site visit by a BLM 
employee in 1992 reported cattle grazing on private land west of Duck 
Creek Slough; the slough did not appear to be heavily impacted by 
cattle and looked in good condition (Barber in litt. 1992a, p. 1). 
Locations for the Steptoe Valley crescentspot occur on or near BLM's 
Steptoe Allotment (BLM 2010b, Appendix II, p. 10; Lichtler, 2012, pers. 
comm.), Duck Creek Flat Allotment (Barber in litt. 1993, p. 1; 
Lichtler, 2012, pers. comm.), and the Heuser Mountain Allotment (Barber 
in litt. 1993, p. 2; Lichtler, 2012, pers. comm.), but also occur on 
private land. It is not known how livestock grazing is managed on 
private land, but general knowledge of these areas indicate they are 
not heavily grazed and habitat conditions are good (Mabey 2012, pers. 
comm.). Current range conditions on BLM allotments that may support 
Steptoe Valley crescentspot habitat have improved in the last 5 years 
through grazing permit renewals with implementation of terms and 
conditions and lower utilization rates, and this would improve any 
habitat for the Steptoe Valley crescentspot (Mabey 2012, pers. comm.). 
Livestock grazing occurs at the Monte Neva Hot Springs area; about 30 
head of cattle and a few domestic horses have access to the area, 
likely year-round (NNHP in litt., 2007, p. 1).
    The best available information does not indicate declines in the 
larval host plant Aster ascendens or adult nectar plant species in 
occupied Steptoe Valley crescentspot habitat due to livestock grazing. 
The larval host plant is widely distributed in Nevada and other western 
States and grows in a wide variety of habitats, including disturbed 
sites (see Biology section). One potential adult nectar plant species, 
Castilleja salsuginosa (Monte Neva paintbrush), is thriving at Monte 
Neva Hot springs and is apparently not being adversely affected by 
livestock grazing (NNHP in litt., 2007, p. 1). Activities involving 
grazing management within the Steptoe Valley crescentspot habitat on 
BLM lands are addressed in consideration of the Ely District Record of 
Decision and Approved RMP (BLM 2008a), BLM's authority under 
Regulations on Grazing Administration Exclusive of Alaska, BLM's 6840 
Manual (BLM 2008b), and possibly NEPA, per our discussion of these 
authorities in our analysis above for the White River Valley skipper. 
We did not receive any additional information as a result of the 90-day 
petition finding notice, nor did we locate information indicating that 
livestock grazing is negatively impacting the habitat or populations of 
the Steptoe Valley crescentspot. Thus, the best available information 
does not indicate that livestock grazing is modifying the subspecies' 
habitat to the extent that it represents a threat to this subspecies 
now or in the future.
Nonnative Plant Invasion
    For general background information on nonnative plant invasion, 
please refer to the Nonnative Plant Invasion section under Factor A. 
The Present or Threatened Destruction, Modification, or Curtailment of 
Its Habitat or Range in the Five-Factor Evaluation for the White River 
Valley Skipper.
    The NNHP (2007, p. 42) states that a portion of Steptoe Valley's 
wetland areas have been degraded or converted to other land uses, 
including nonnative species invasion. Although they are likely to occur 
to some extent within the range of the Steptoe valley crescentspot, 
nonnative invasive plant species are not known to be a problem in 
Steptoe Valley crescentspot habitat (Mabey 2012, pers. comm.). There is 
no information indicating that nonnative plants are adversely affecting 
the Steptoe Valley crescentspot's larval host plant, Aster ascendens, 
or the butterfly's adult nectar plants. Activities involving nonnative 
plant species management within the Steptoe Valley crescentspot habitat 
on BLM lands would be addressed in consideration of the Ely District 
Record of Decision and Approved RMP (BLM 2008a), BLM's authority under 
Regulations on Grazing Administration Exclusive of Alaska, the Plant 
Protection Act of 2000, BLM's programmatic EIS for vegetation 
treatments on BLM's administered lands in the western United States 
(BLM 2007a), BLM's 6840 Manual (BLM 2008b), and possibly NEPA, as these 
authorities are discussed in our analysis for White River Valley 
skipper, above. Activities involving nonnative plant species management 
and control on private lands within the Steptoe Valley crescentspot 
habitat could also be addressed in consideration of the Plant 
Protection Act of 2000. We did not receive any further information as a 
result of our 90-day petition finding notice, nor did we locate 
information indicating that nonnative or invasive plant species are 
negatively impacting populations of the Steptoe Valley crescentspot. 
Thus, the best available information does not indicate that

[[Page 54311]]

nonnative plant species are modifying the subspecies' habitat to the 
extent that it represents a threat to this subspecies now or in the 
future.
Agriculture
    For general background information on agriculture, please refer to 
the Agriculture section under Factor A. The Present or Threatened 
Destruction, Modification, or Curtailment of Its Habitat or Range in 
the Five-Factor Evaluation for the White River Valley Skipper.
    The NNHP (2007, p. 42) states that a portion of Steptoe Valley's 
wetland areas have been degraded or converted to other land uses, 
including agriculture. Although agriculture (hayfields) is known to 
occur near the Duck Creek-Bassett Lake and Monte Neva sites, 
agriculture does not occur within Steptoe Valley crescentspot habitat 
as the soils are not suitable because they are too moist and saline 
(Mabey 2012, pers. comm.). The best available information does not 
indicate that agriculture is occurring in areas that are occupied by 
the Steptoe Valley crescentspot. We did not receive any information as 
a result of the 90-day petition finding notice, nor did we locate 
information that indicates agriculture is negatively impacting Steptoe 
Valley crescentspot populations, host plants, or nectar sources. 
Therefore, the best available information does not indicate that 
agriculture is modifying the subspecies' habitat to the extent that it 
represents a threat to this subspecies now or in the future.
Mining and Energy Development
    For general background information on mining and energy 
development, please refer to the Mining and Energy Development section 
under Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range in the Five-Factor Evaluation for 
the White River Valley Skipper.
    The NNHP (2007, p. 42) states that a portion of wetland areas in 
Steptoe Valley have been degraded or converted to other land uses, 
including mining and energy development. A copper ore smelter, 
concentrator, and tailings facility was constructed in McGill in the 
early 1900s and operated until the early 1980s (http://www.mii.org Web 
site accessed April 26, 2012). It is not known the amount, if any, of 
Steptoe Valley crescentspot habitat that may have been impacted at the 
time of the facility's construction. During the late 1980s and early 
1990s the site was reclaimed; the tailings area was reclaimed as 
pasture for livestock grazing (http://www.mii.org Web site accessed 
April 26, 2012).
    Though the Steptoe Valley crescentspot is known from the project 
area for the Southwest Intertie Project, impacts to it were not 
identified (BLM 1993, pp. 3-75-3-89). This subspecies was also not 
observed during wildlife surveys conducted for the One Nevada 
Transmission Line Project (BLM 2010c, Appendix 3D, Table 2, pp. 1-5). 
Actions involving mineral and energy development within Steptoe Valley 
crescentspot habitat on BLM-administered lands would be addressed in 
consideration of the Ely District Record of Decision and Approved RMP 
(BLM 2008a), the FLPMA of 1976, the Mineral Leasing Act of 1920, BLM's 
6840 Manual (BLM 2008b), and NEPA, per our analysis of these 
authorities above for the White River Valley skipper. The best 
available information does not indicate energy development is impacting 
Steptoe Valley crescentspot habitat or populations. We did not receive 
any additional information as a result of our 90-day petition finding 
notice, nor did we locate information indicating that mining or energy 
development is negatively impacting the subspecies' habitat. Thus, the 
best available information does not indicate that mining or energy 
development is modifying the subspecies' habitat to an extent that they 
represent a threat to this subspecies now or in the future.
Climate Change
    For general background information on climate change, please refer 
to the Climate Change section under Factor A. The Present or Threatened 
Destruction, Modification, or Curtailment of Its Habitat or Range in 
the Five-Factor Evaluation for the White River Valley Skipper.
    While the petition asserts that climate change may impact Steptoe 
Valley crescentspot (WildEarth Guardians 2010, p. 40), it is difficult 
to predict local climate change impacts, due to substantial uncertainty 
in trends of hydrological variables, limitations in spatial and 
temporal coverage of monitoring networks, and differences in the 
spatial scales of global climate models and hydrological models (Bates 
et al. 2008, p. 3). We found no information on how climate change may 
impact the Steptoe Valley crescentspot's host plant, Symphyotrichum 
ascendens, or adult nectar sources. In general, increasing temperatures 
and drought frequency, more winter precipitation in the form of rain, 
possible decreases in summer rain, and earlier, rapid snowmelt could 
impact the host plant by causing physiological stress, altering 
phenology, reducing recruitment events, and reducing seed 
establishment. However, at this time, it is difficult to predict local 
climate change impacts to Symphyotrichum ascendens or Steptoe Valley 
crescentspot's adult nectar sources and how individual plant species 
will react to climate change. Thus, while information indicates that 
climate change has the potential to affect vegetation and habitats used 
by the Steptoe Valley crescentspot in the Great Basin, there is much 
uncertainty regarding which habitat attributes could be affected, and 
the timing, magnitude, and rate of their change as it relates to this 
subspecies.
    We did not receive any information as a result of our 90-day 
petition finding notice, nor did we locate specific information that 
indicates climate change is negatively impacting Steptoe Valley 
crescentspot populations or their habitats. Therefore, the best 
available information does not indicate that climate change is 
modifying the subspecies' habitat to an extent that it represents a 
threat to this subspecies now or is likely to in the future.
Summary of Factor A
    While activities such as water development, livestock grazing, 
nonnative species invasion, agriculture, and mining and energy 
development may be impacting a portion of wetland areas in Steptoe 
Valley, available information does not indicate that these impacts are 
negatively impacting occupied Steptoe Valley crescentspot habitat. The 
available information does not indicate that these activities, or 
climate change, are negatively impacting populations of Steptoe Valley 
crescentspot. Since the Steptoe Valley crescentspot is associated with 
wetland areas, impacts from water development could impact the 
subspecies; however, known occupied locations are outside the greater 
than 10-foot (3.0-m) drawdown contour for the SNWA proposed project, 
and impacts are not anticipated. While information indicates that 
climate change has the potential to affect vegetation used by this 
subspecies, much uncertainty remains regarding which plant attributes 
may be affected, and the timing, magnitude, and rate of their change. 
We conclude based on the best scientific and commercial information 
available that the present or threatened destruction, modification, or 
curtailment of its habitat or range does not currently pose a threat to 
the Steptoe Valley crescentspot, nor is it likely to become a threat to 
the subspecies in the future.

[[Page 54312]]

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    For general background information on overutilization, please refer 
to the discussion on collecting under Factor B. Overutilization for 
Commercial, Recreational, Scientific, or Educational Purposes in the 
Five-Factor Evaluation for the White River Valley Skipper.
    We are unaware of any studies analyzing impacts of removal of 
individuals from populations of the Steptoe Valley crescentspot. Austin 
(1998b, p. 577) indicates 39 males and 10 females were collected 
between 1981 and 1989 at one site. No additional information is known 
about the numbers of specimens collected in the past, and we are not 
aware of any ongoing or current collecting of this subspecies. Given 
the low number of individuals collected over this 8-year period, the 
length of time since the collections were made, and the lack of 
information about the relative impact to the populations, the available 
information does not indicate that collection may be a threat to this 
subspecies.
    There has been no information presented that documents that 
overutilization has led to the loss of populations or a significant 
reduction in numbers of individuals for this subspecies. Therefore, we 
conclude based on the best scientific and commercial information 
available that overutilization for commercial, recreational, 
scientific, or educational purposes does not currently pose a threat to 
the Steptoe Valley crescentspot, nor is it likely to become a threat to 
the subspecies in the future.

Factor C. Disease or Predation

    We found no information on the incidence of disease in the Steptoe 
Valley crescentspot.
    Predation by other species, such as birds or insects, on eggs, 
larvae, pupae, or adult Steptoe Valley crescentspots is assumed, but we 
found no information indicating that predation levels are any greater 
than naturally occurring levels typical of the biological community in 
which the Steptoe Valley crescentspot occurs.
    Available information does not indicate that there are impacts from 
disease or predation on the Steptoe Valley crescentspot. Therefore, we 
conclude that the best scientific and commercial information available 
does not indicate that disease or predation currently pose a threat to 
the Steptoe Valley crescentspot, nor is either likely to become a 
threat to the subspecies in the future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The discussion of existing regulatory mechanisms under Factor D for 
the White River Valley skipper is hereby incorporated into this 
discussion for the Steptoe Valley crescentspot. As discussed above 
under Factor D for the White River Valley skipper, Nevada State law 
pertaining to wildlife does not offer protection to the Steptoe Valley 
crescentspot specifically because it is an invertebrate species not 
classified as wildlife. Although not protected by State wildlife law, 
the best available information, as discussed in Factor B, does not 
indicate that collection or other forms of overutilization is a threat 
to the Steptoe Valley crescentspot. In addition, the State's water law 
may offer some protection to species dependent on water resources such 
as the Steptoe Valley crescentspot as it occurs in a ``designated'' 
basin with a preferred use identified.
    A portion of habitat for the Steptoe Valley crescentspot occurs on 
Federal lands administered by BLM. Numerous policies, guidance, and 
laws have been developed to assist the agency in management of these 
lands (see Factor D discussion under White River Valley skipper). BLM 
policies and guidance address species of concern, actions covered by 
RMPs, and regulatory authority for grazing and oil and gas leasing and 
operating activities. As discussed under Factor A, the best available 
information does not indicate that activities such as livestock 
grazing, nonnative species invasion, and mining and energy development 
that are regulated by various policies, guidance, and laws on Federal 
lands are negatively impacting Steptoe Valley crescentspot populations. 
We conclude based on the best scientific and commercial information 
available that the inadequacy of existing regulatory mechanisms does 
not currently pose a threat to the Steptoe Valley crescentspot, nor is 
it likely to become a threat to the subspecies in the future.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Potential other natural or manmade factors that may affect the 
continued existence of the Steptoe Valley crescentspot are discussed in 
this section and include: (1) Limited range and (2) small population 
size(s).
    For general background information on other natural or manmade 
factors which could affect the Steptoe Valley crescentspot, please 
refer to the discussion on limited distribution and population size 
under Factor E. Other Natural or Manmade Factors Affecting Its 
Continued Existence in the Five-Factor Evaluation for the White River 
Valley Skipper.
    As indicated earlier, the Steptoe Valley crescentspot occurs at 
locations along Duck Creek and at Monte Neva Hot Springs in Steptoe 
Valley and possibly near the Ruby Mountains. Little information is 
available related to its distribution and numbers of populations, and 
no information is available regarding population sizes, loss of 
populations, if any, or population trends for the Steptoe Valley 
crescentspot. Information pertaining to the aerial extent of habitat or 
populations is not available. The best available information does not 
include comprehensive surveys for this subspecies. Without data to 
indicate population trends, it is difficult to support claims of 
adverse impacts to the Steptoe Valley crescentspot. We found no 
information on connections between chance events and population impacts 
for the Steptoe Valley crescentspot. Since this subspecies is 
distributed over different areas, potential impacts due to stochastic 
events is reduced. In the absence of chance events connected to known 
populations, we do not consider small population numbers or limited 
range by themselves to be threats to this subspecies. The best 
available information does not indicate the Steptoe Valley crescentspot 
is negatively impacted by limited range or small population numbers. We 
conclude based on the best scientific and commercial information 
available that other natural or manmade factors do not currently pose a 
threat to the Steptoe Valley crescentspot, nor are they likely to 
become a threat to the subspecies in the future.

Synergistic Interactions Between Threat Factors

    We have evaluated individual threats to the Steptoe Valley 
crescentspot. This subspecies faces potential threats from water 
development, livestock grazing, nonnative plant invasion, agriculture, 
mining and energy development, limited range, small population size, 
and climate change. In considering whether the threats to a species may 
be so great as to warrant listing under the Act, we must look beyond 
the possible impacts of potential threats in isolation and consider the 
potential cumulative impacts of all of the threats facing a species.
    In making this finding, we considered whether there may be 
cumulative effects to the Steptoe Valley crescentspot from the combined 
impacts of the existing

[[Page 54313]]

stressors such that even if each stressor individually does not result 
in population-level impacts, that cumulatively the effects may be 
significant. We considered whether the combined effects of water 
development and mining and energy development may result in a 
significant impact to the Steptoe Valley crescentspot because these 
potential impacts have the potential to result in some level of habitat 
loss. However, we conclude that synergistic effects between water 
development and mining and energy development are unlikely to result in 
a significant overall population impact to the Steptoe Valley 
crescentspot because water development activities have been ongoing in 
the valley, and the proposed SNWA water development project is not 
anticipated to cause impacts to this subspecies because sites occupied 
by the butterfly are located outside of the estimated project impact 
area. Also, impacts from mining and energy development are not found to 
be occurring in the butterfly's habitat.
    While livestock grazing and nonnative plant invasion could impact 
the Steptoe Valley crescentspot and its habitat, observations of 
private land within the subspecies' habitat that are being grazed look 
to be in good condition; changes in livestock grazing management on BLM 
sites that may be occupied by the butterfly have improved habitat 
conditions for this subspecies; and nonnative plant species invasion is 
not known to be a concern on either private or public lands. We 
conclude that livestock grazing and nonnative plant species invasion 
impacts combined with impacts from water development would not be of 
sufficient severity, frequency, or geographic scope to result in 
significant habitat impacts or cause population-level impacts to the 
Steptoe Valley crescentspot. Agriculture and mining and energy 
development were not found to occur within this subspecies' habitat 
and, therefore, will not have a cumulative impact on the Steptoe Valley 
crescentspot.
    Limited range and small population size could make the Steptoe 
Valley crescentspot more vulnerable to potential threats discussed 
above. However, we cannot conclude that synergistic effects between 
limited range and small population size and other potential threats are 
operative threats to the continued existence of the Steptoe Valley 
crescentspot given the lack of information on the range and population 
size of this butterfly. There is no information on population size or 
change in population abundance for the Steptoe Valley crescentspot, and 
the limited information on occurrence (distribution) is insufficient to 
define this butterfly's range.
    Synergistic interactions are possible between effects of climate 
change and effects of other potential threats such as livestock grazing 
and nonnative plant invasion. Increases in carbon dioxide and 
temperature and changes in precipitation are likely to affect 
vegetation, and the Steptoe Valley crescentspot is closely associated 
with the presence of vegetation. However, it is difficult to project 
how climate change will affect vegetation because certain plant species 
may increase in cover while other species may decrease. Uncertainty 
about how different plant species will respond under climate change, 
combined with uncertainty about how changes in plant species 
composition would affect suitability of Steptoe Valley crescentspot 
habitat, make projecting possible synergistic effects of climate change 
on the Steptoe Valley crescentspot too speculative.

Finding for the Steptoe Valley Crescentspot

    As required by the Act, we considered the five factors is assessing 
whether the Steptoe Valley crescentspot is an endangered or threatened 
species throughout all of its range. We examined the best scientific 
and commercial information available regarding the past, present, and 
future threats faced by this subspecies.
    Factors potentially affecting the Steptoe Valley crescentspot, 
including water development, livestock grazing, nonnative species 
invasion, agriculture, mining and energy development, or climate 
change, and limited range and small population size, are either limited 
in scope or lack documentation that they are occurring in occupied 
habitat and adversely impacting the subspecies. Though climate change 
may be affecting the Steptoe Valley crescentspot and its habitats and 
effects are likely to increase in the future, available information 
does not support a determination that climate change has or will result 
in a population-level impact to this subspecies. Available information 
does not indicate that overutilization, disease, or predation is a 
threat to the Steptoe Valley crescentspot. Lastly, the available 
information does not indicate that existing regulatory mechanisms are 
inadequate to protect the subspecies from potential threats. 
Furthermore, there is no evidence to indicate that the combined factors 
acting together are a threat to the Steptoe Valley crescentspot. Based 
on our review of the best scientific and commercial information 
available, we find these stressors, either singly or in combination 
with one another, are not threats to the Steptoe Valley crescentspot or 
its habitat.
    We found no information to indicate that threats are of sufficient 
imminence, intensity, or magnitude such that the Steptoe Valley 
crescentspot is in danger of extinction (endangered) or likely to 
become endangered within the foreseeable future (threatened), 
throughout all of its range. Therefore, we find that listing the 
Steptoe Valley crescentspot as an endangered or threatened species is 
not warranted throughout its range.

Significant Portion of the Range

    Having determined that the Steptoe Valley crescentspot does not 
meet the definition of an endangered or a threatened species, we must 
next consider whether there are any significant portions of the range 
where the Steptoe Valley crescentspot is in danger of extinction or is 
likely to become endangered in the foreseeable future. The Act defines 
``endangered species'' as any species which is ``in danger of 
extinction throughout all or a significant portion of its range,'' and 
``threatened species'' as any species which is ``likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' 16 U.S.C. 1532(6) and 1532(20). The 
definition of ``species'' is also relevant to this discussion. The Act 
defines ``species'' as follows: ``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). The phrase ``significant portion of 
its range'' (SPR) is not defined by the statute, and we have never 
addressed in our regulations: (1) The consequences of a determination 
that a species is either endangered or likely to become so throughout a 
significant portion of its range, but not throughout all of its range; 
or (2) what qualifies a portion of a range as ``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountains gray wolf (74 FR 15123, April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the

[[Page 54314]]

Gunnison's prairie dog (73 FR 6660, February 5, 2008). The Service had 
asserted in both of these determinations that, under the Act, it had 
authority, in effect, to protect only some members of a ``species,'' as 
defined by the Act (i.e., species, subspecies, or DPS). Both courts 
ruled that the determinations were arbitrary and capricious on the 
grounds that this approach violated the plain and unambiguous language 
of the Act. The courts concluded that reading the SPR language to allow 
protecting only a portion of a species' range is inconsistent with the 
Act's definition of ``species.'' The courts concluded that once a 
determination is made that a species (i.e., species, subspecies, or 
DPS) meets the definition of ``endangered species'' or ``threatened 
species,'' it must be placed on the list in its entirety and the Act's 
protections applied consistently to all members of that species 
throughout its range (subject to modification of protections through 
special rules under sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing. Thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be endangered or threatened throughout all 
of its range, or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout an SPR, it, the species, is an ``endangered 
species.'' The same analysis applies to ``threatened species.'' Based 
on this interpretation and supported by existing case law, the 
consequence of finding that a species is endangered or threatened in 
only a significant portion of its range is that the entire species 
shall be listed as endangered or threatened, respectively, and the 
Act's protections shall be applied across the species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the SPR phrase as providing an independent basis for listing is the 
best interpretation of the Act because it is consistent with the 
purposes and the plain meaning of the key definitions of the Act; it 
does not conflict with established past agency practice (i.e., prior to 
the 2007 Solicitor's Opinion), as no consistent, long-term agency 
practice has been established; and it is consistent with the judicial 
opinions that have most closely examined this issue. Having concluded 
that the phrase ``significant portion of its range'' provides an 
independent basis for listing and protecting the entire species, we 
next turn to the meaning of ``significant'' to determine the threshold 
for when such an independent basis for listing exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that, 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether, without that portion, the 
representation, redundancy, or resiliency of the species would be so 
impaired that the species would have an increased vulnerability to 
threats to the point that the overall species would be in danger of 
extinction (i.e., would be ``endangered''). Conversely, we would not 
consider the portion of the range at issue to be ``significant'' if 
there is sufficient resiliency, redundancy, and representation 
elsewhere in the species' range that the species would not be in danger 
of extinction throughout its range if the population in that portion of 
the range in question became extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that, without that portion, 
the species would be in danger of extinction) establishes a threshold 
that is relatively high. On the one hand, given that the consequences 
of finding a species to be endangered or threatened in an SPR would be 
listing the species throughout its entire range, it is important to use 
a threshold for ``significant'' that is robust. It would not be 
meaningful or appropriate to establish a very low threshold whereby a 
portion of the range can be considered ``significant'' even if only a 
negligible increase in extinction risk would result from its loss. 
Because nearly any portion of a species' range can be said to 
contribute some increment to a species' viability, use of such a low 
threshold would require us to impose restrictions and expend 
conservation resources disproportionately to conservation benefit: 
Listing would be rangewide, even if only a portion of the range of 
minor conservation importance to the species is imperiled. On the other 
hand, it would be inappropriate to establish a threshold for 
``significant'' that is too high. This would be the case if the 
standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the SPR phrase independent meaning, as the 
Ninth Circuit held in Defenders of Wildlife v. Norton, 258 F.3d 1136 
(9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the

[[Page 54315]]

threshold so high that the phrase ``in a significant portion of its 
range'' loses independent meaning. Specifically, we have not set the 
threshold as high as it was under the interpretation presented by the 
Service in the Defenders litigation. Under that interpretation, the 
portion of the range would have to be so important that current 
imperilment there would mean that the species would be currently 
imperiled everywhere. Under the definition of ``significant'' used in 
this finding, the portion of the range need not rise to such an 
exceptionally high level of biological significance. (We recognize that 
if the species is imperiled in a portion that rises to that level of 
biological significance, then we should conclude that the species is in 
fact imperiled throughout all of its range, and that we would not need 
to rely on the SPR language for such a listing.) Rather, under this 
interpretation, we ask whether the species would be endangered 
everywhere without that portion (i.e., if that portion were completely 
extirpated). In other words, the portion of the range need not be so 
important that even the species being in danger of extinction in that 
portion would be sufficient to cause the species in the remainder of 
the range to be endangered; rather, the complete extirpation (in a 
hypothetical future) of the species in that portion would be required 
to cause the species in the remainder of the range to be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it might be more efficient for us to address 
the significance question first or the status question first. Thus, if 
we determine that a portion of the range is not ``significant,'' we do 
not need to determine whether the species is endangered or threatened 
there; if we determine that the species is not endangered or threatened 
in a portion of its range, we do not need to determine if that portion 
is ``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the Steptoe Valley crescentspot 
to determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the subspecies, including water 
development, livestock grazing, nonnative species invasion, 
agriculture, mining and energy development, climate change, limited 
range, and small population size. On the basis of our review, we found 
no geographic concentration of threats either on public or private 
lands to suggest that the Steptoe Valley crescentspot may be in danger 
of extinction in that portion of its range. We found no area within the 
range of the Steptoe Valley crescentspot where the potential threats 
are significantly concentrated or substantially greater than in other 
portions of its range. We also found that lost historical range does 
not constitute a significant portion of the range for the Steptoe 
Valley crescentspot because there is no information indicating that 
there has been a range contraction for this subspecies. Therefore, we 
find factors affecting the subspecies are essentially uniform 
throughout its range, indicating no portion of the butterfly's range 
warrants further consideration of possible status as an endangered or 
threatened species under the Act.
    We found no information to indicate that the Steptoe Valley 
crescentspot is in danger of extinction now, nor is it likely to become 
endangered within the foreseeable future, throughout all or a 
significant portion of its range. Therefore, listing the Steptoe Valley 
crescentspot as an endangered or threatened species under the Act is 
not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the Steptoe Valley crescentspot to our Nevada 
Fish and Wildlife Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor the Steptoe Valley 
crescentspot and encourage its conservation. If an emergency situation 
develops for the Steptoe Valley crescentspot or any other species, we 
will act to provide immediate protection.

Species Information for Baking Powder Flat Blue Butterfly

Taxonomy and Species Description

    We accept the characterization of the Baking Powder Flat blue 
butterfly (Euphilotes bernardino minuta) as a valid subspecies based on 
its description by Austin (1998c, p. 549). This subspecies is in the 
Lycaenidae family (Austin 1998c, p. 539; 1998b, p. 841) and was an 
unnamed segregate of the E. battoides complex in Nevada (Austin 1998c, 
p. 549). The male's wingspan ranges from 0.35 to 0.40 inch (in) (9.0-
10.2 mm). The upper side of the male is purplish-blue with a black 
outer margin (wing edge) of moderate width. Veins are black distally 
(away from the point of attachment) on both wings. Submarginal orange 
often occurs in posterior (behind or at the rear) cells on the 
hindwing. Wing fringes are white and lightly checkered with gray. The 
underside of the male's wings is grayish-white; there is a slight 
posterior gray flush on the forewing and the hindwing has an orange 
aurora (colored marginal band of hindwing) of moderate width (Austin 
1998c, p. 549). The female's wingspan ranges from 0.43 to 0.97 in (9.7-
11.0 mm). The upper side of the wing is a dark brownish-gray and 
slightly grayer basally. The hindwing has an orange aurora of moderate 
width and is outlined with blackish marginal spots distally. Wing 
fringes and the undersides are like that of the male (Austin 1998c, p. 
549). Please refer to Austin (1998c, p. 549) for a more detailed 
description of this subspecies.

Distribution and Habitat

    Descriptions of locations where the Baking Powder Flat blue 
butterfly has been found are vague, but this subspecies is only known 
from the Baking Powder Flat area (on BLM lands) in Spring Valley, in 
Lincoln and White Pine Counties, Nevada, a flat valley bottom with 
scattered sand dunes (Austin 1998c, p. 550; Austin and Leary 2008, pp. 
68-69). The type locality is located approximately 1.0 mi (1.6 km) from 
Blind Spring in Baking Powder Flat (Spring Valley, White Pine County) 
(Austin 1998c, p. 550). The Baking Powder Flat area also contains areas 
of wetland-type habitats (wetlands, springs, seeps). The Baking Powder 
Flat area contains the largest known contiguous habitat for the Baking 
Powder Flat blue butterfly (BLM 2009a,

[[Page 54316]]

p. 20). In 1993, Austin (1993, p. 5) reported two occupied sites for 
the Baking Powder Flat blue butterfly in the Baking Powder Flat area in 
southern Spring Valley, and also suggested that other areas could 
support the host plant (Austin 1993, pp. 5-6), indicating a possible 
wider distribution of this butterfly. The only documented host plant, 
Eriogonum shockleyi (Shockley's buckwheat), which the Baking Powder 
Flat blue butterfly uses for both larval and adult life stages (see 
Biology section below), is a perennial forb (http://www.plants.usda.gov, accessed January 6, 2012) and grows on relatively 
hard and bare areas between the sand dunes in the Baking Powder Flat 
area (Austin 1993, p. 5; 1998c, p. 550). In this area the plants occur 
in large, open, loose mats (Kartesz 1987, pp. 282-283).
    Throughout its range, Eriogonum shockleyi grows mostly on gravelly, 
clayey, or sandy soils, or on rocky outcrops and ledges, in association 
with Sarcobatus sp. (greasewood), Atriplex sp. (shadscale), and 
Artemisia sp. (sagebrush) (Kartesz 1987, p. 282); it is not a wetland-
dependent species. The host plant (E. shockleyi) is common in Nevada, 
occurring in Mineral, Esmeralda, Nye, Lincoln, Clark, White Pine, and 
Elko Counties (Kartesz 1987, p. 282). It is also known to occur in 
California, Idaho, Utah, Colorado, New Mexico, and Arizona (Kartesz 
1987, p. 283; http://www.plants.usda.gov, accessed January 6, 2012). 
Searches of nearby areas in southern Spring Valley did not reveal 
additional colonies of the subspecies or its host plant (Austin 1993, 
p. 5; 1998c, p. 550); however, Austin and Leary (2008, pp. 68-69) list 
what appear to be seven discrete locations in the Baking Powder Flat 
area where this subspecies (adults and larvae) has been seen between 
1969 and 2002.
    The NNHP database (2010) also indicates that this subspecies occurs 
in the Baking Powder Flat area near Blind Spring. The site was visited 
seven times between 1969 and 2002 (Austin and Leary 2008, pp. 68-69). 
The other six sites identified by Austin and Leary (2008, pp. 68-69) 
were visited once (five of the sites) or three times (one site) between 
the late 1980s and early 2000s. During a general terrestrial 
invertebrate survey conducted in 2006 at 76 sites in eastern Nevada, 
including 37 sites in Spring Valley (2 of which could be in or near 
known locations for this subspecies), the Baking Powder Flat blue 
butterfly was not encountered (Ecological Sciences, Inc. 2007, pp. 80-
82). The aerial extent of each occupied site or the host plant, or host 
plant abundance, has not been reported. The Baking Powder Flat Area of 
Critical Environmental Concern (ACEC) encompasses most, if not all, of 
the known Baking Powder Flat blue butterfly locations. A few of the 
locations may occur outside of the ACEC as all of the site descriptions 
are not clear.

Biology

    The Baking Powder Flat blue butterfly is associated with Eriogonum 
shockleyi on which both larvae and adults are found (Austin 1993, p. 5; 
Austin and Leary 2008, pp. 68-69). Larvae of this subspecies are tended 
by ants (Formica obtusopilosa) (Shields 1973 cited by Austin 1993, p. 
5). Pupae are likely formed in and protected by litter that is in and 
beneath the host plant (Austin 1993, p. 5). Adults fly between mid and 
late June (Austin 1993, p. 6; 1998c, p. 550), and there is one brood 
(Austin 1993, p. 6).
    There is little biological information available at the subspecies 
level, but some inferences can be made from biological information from 
related species at the species level. Information for the buckwheat 
blue (Euphilotes battoides) indicates eggs are pale bluish-white, 
turning white, and they are laid singly on the host plant's flowers 
(Scott 1986, p. 403). Larvae eat flowers and fruit and are attended by 
ants (Scott 1986, p. 403). No nests are constructed (Scott 1986, p. 
403). Adults sip flower nectar and mud, and males patrol around the 
host plant during the day seeking females (Scott 1986, p. 403).
    The best available information does not include surveys documenting 
this subspecies' population dynamics, nor its overall abundance, number 
or size of populations, number of extirpated populations or sites, if 
any, or population trends.

Five-Factor Evaluation for the Baking Powder Flat Blue Butterfly

    Information pertaining to the Baking Powder Flat blue butterfly in 
relation to the five factors provided in section 4(a)(1) of the Act is 
discussed below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    Potential factors that may affect the habitat or range of the 
Baking Powder Flat blue butterfly are discussed in this section, 
including: (1) Water development, (2) fire, (3) livestock grazing, (4) 
nonnative plant invasion, (5) agriculture, (6) recreation (off-highway 
vehicles), (7) mining and energy development, (8) plant collection, and 
(9) climate change.
Water Development
    For general background information on water development, please 
refer to the Water Development section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    The NNHP (2007, p. 42) estimates that about 30 percent of the 
Baking Powder Flat playa/ephemeral pool/spring pool complex has been 
degraded or converted to other land uses, including by water 
development. The NNHP (2007) does not delineate this area on a map or 
define it in terms of acreage; therefore, the amount of Baking Powder 
Flat blue butterfly habitat that may occur within this area and may be 
impacted by various land use practices, if any, is not documented. 
However, it is important to note that the Baking Powder Flat blue 
butterfly's host plant occurs in dry areas and not within wetland 
areas. The extent to which the various land use practices have degraded 
or converted this area is also not individually delineated or 
quantified by NNHP (2007).
    Concerns have been raised regarding SNWA's proposed water 
development project and its potential impacts to the Baking Powder Flat 
area and the Baking Powder Flat ACEC (Charlet 2006, p. 19; BLM 2009a, 
pp. 20-21). During ROWs surveys for various facilities associated with 
the SNWA project (i.e., powerlines, pipelines), the Baking Powder Flat 
blue butterfly was not observed (BLM 2011a, pp. 3.6-19; 3.14-4), but 
all facility locations have not yet been determined (BLM 2011a, p. 2-
5). The butterfly has been recorded from Spring Valley within the 
proposed groundwater development area within the ACEC (BLM 2011a, pp. 
3.6-22; 3.14-4); this location is in reference to the site near Blind 
Spring. The Baking Powder Flat blue butterfly and its habitat could be 
impacted during construction and facility maintenance activities by 
direct mortality resulting from construction or vehicles, disruption of 
breeding success, temporary or permanent loss of habitat, and habitat 
fragmentation (BLM 2011a, p. 3.6-70). However, BLM mitigation 
recommendation GW-WL-6 has been included in the proposed project (BLM 
2011a, p. 3.6-70). This mitigation recommendation involves pre-
construction surveys and the avoidance of Baking Powder Flat blue 
butterfly occurrence sites and habitat during facility siting to the 
extent practicable (BLM 2011a, p. 3.6-71). Because the ACEC is large 
(13,640 ac (5,520 ha)) (72 FR 67748, November 30, 2007), any

[[Page 54317]]

facilities constructed, if approved, would impact a small percentage of 
the ACEC's area. This is in addition to the restoration requirements 
provided for in the BLM's Ely RMP (BLM 2011a, p. 3.6-70) and BLM's 
determination for the Baking Powder Flat ACEC that an issuance of a ROW 
permit will result in minimal conflict with identified resource values 
and that impacts can be mitigated.
    In addition to possible construction impacts, the groundwater flow 
model estimate for 200 years post full buildout (BLM 2011a, p. 3.3-102) 
shows Blind Spring within the project's greater than 10-foot (3.0-m) 
drawdown contour. Blind Spring is located in the ACEC and within 1 mi 
(1.6 km) of some Baking Powder Flat blue butterfly observations (Austin 
and Leary 2008, pp. 68-69). As stated earlier, the host plant, 
described as common in Baking Powder Flat (BLM 2009a, p. 20), grows on 
relatively hard and bare areas between sand dunes (Austin 1998c, p. 
550) and mostly on gravelly, clayey, or sandy soils, or on rocky 
outcrops and ledges in association with upland plants (Kartesz 1987, p. 
282); it is not a wetland-dependent species. Therefore, it is unlikely 
SNWA's proposed water development project will indirectly impact the 
Baking Powder Flat blue butterfly in Spring Valley through groundwater 
drawdowns. The Baking Powder Flat blue butterfly habitat is not 
specifically considered in the Spring Valley Stipulation because the 
subspecies and its habitat are not considered to be at risk from 
groundwater development (SNWA, in litt. 2011, p. 36).
    Because the Baking Powder Flat blue butterfly's host plant grows in 
dry areas and not within the Baking Powder Flat wetland areas, it is 
unlikely that current groundwater rights or SNWA's proposed water 
development project which have been and are considered under Nevada 
water law will indirectly impact the butterfly through groundwater 
drawdowns. The host plant is considered common in the Baking Powder 
Flat area, and the butterfly has been documented in several areas in 
the ACEC, and possibly outside it as some butterfly location 
descriptions are unclear. Any facilities constructed in the ACEC would 
impact a small percentage (unknown at this time) of the ACEC's total 
area and would be mitigated by SNWA project mitigations or BLM 
requirements. At this time, the best available information does not 
indicate that water development is modifying the subspecies' habitat or 
that its habitat may be modified through SNWA's proposed project to the 
extent that it represents a threat to this subspecies now or in the 
future.
Fire
    Butterflies have specialized habitat requirements (Thomas 1984, p. 
337). Changes in the structure and composition of vegetation due to 
natural or other means can threaten butterfly populations as these 
changes can disrupt specific habitat requirements (Thomas 1984, pp. 
337-341). The effects of fire on the landscape depend on the 
composition of plant species present, and the size, frequency, and 
intensity of fire. Burning can also allow invasive species, such as 
Bromus tectorum, to increase (Stewart and Hull 1949 and Wright and 
Britton 1976, cited in Yensen 1982, p. 28).
    Fleischman (2000, pp. 688-689) found that a prescribed fire in a 
watershed in Nevada did not appear to affect butterfly species richness 
or composition between burned areas and their paired controls. Vogel et 
al. (2007, p. 78) evaluated three restoration practices in prairie 
habitat on butterfly communities and found that the total butterfly 
abundance was highest in areas restored through burning and grazing, 
and was lowest in areas that were only burned. Species richness did not 
differ among the practices. Species diversity was highest in areas that 
were only burned. Individual butterfly species responses to the 
restoration practices were variable.
    The petition mentions fire as a potential threat to the Baking 
Powder Flat blue butterfly (Bruce Boyd, pers. comm. cited in Wild Earth 
Guardians 2010, p. 14) though it does not provide specific information 
to support this claim. Fires have occurred in many areas of Nevada over 
the years and will occur in the future. The best available information 
does not indicate that fire has occurred in areas that are occupied by 
the Baking Powder Flat blue butterfly (Podborny 2012, pers. comm.). The 
Baking Powder Flat area occurs in a valley bottom with sandy soils and 
widespread vegetation, thus the amount and distribution of vegetation 
needed to support a fire through this area are not available (Podborny 
2012, pers. comm.). In addition, the host plant, Eriogonum shockleyi, 
remains common in the Baking Powder Flat area (BLM 2009a, p. 20). 
Actions regarding fire management within Baking Powder Flat blue 
butterfly habitat would be addressed in consideration of the Ely 
District Record of Decision and Approved RMP (BLM 2008a), BLM's 6840 
Manual (BLM 2008b) (see our discussion of these authorities in the 
analysis of the White River Valley skipper), the Emergency 
Stabilization and Burned Area Rehabilitation Program, Baking Powder 
Flat ACEC restrictions, and possibly NEPA. We did not receive any 
information as a result our 90-day petition finding notice, nor did we 
locate information indicating that fire is impacting the habitat or 
populations of the Baking Powder Flat blue butterfly. Consequently, the 
best available information does not indicate that fire is modifying the 
subspecies' habitat to the extent that it is a threat to this 
subspecies now or in the future.
Livestock Grazing
    For general background information on livestock grazing, please 
refer to the Livestock Grazing section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    The NNHP (2007, p. 42) indicates that a portion of the Baking 
Powder Flat playa/ephemeral pool/spring pool complex has been degraded 
or converted to other land uses, including livestock grazing. The 
petition indicates that livestock will graze Eriogonum shockleyi 
(WildEarth Guardians 2010, p. 13), but disturbance to this host plant 
from trampling and soil compaction from livestock was mentioned in the 
petition and by others as a greater potential threat (Austin 1993, p. 
7; Austin et al., in litt. 2000, p. 3; NatureServe 2009c, p. 2; B. 
Boyd, pers. comm. cited in WildEarth 2010, p. 13), though specific 
information to support this concern is not provided. Injury to or loss 
of host plant populations would negatively impact larvae and adults as 
both life stages utilize this plant for food and shelter. Livestock 
grazing is occurring over widespread general habitat areas where the 
Baking Powder Flat blue butterfly is either known to occur or could be 
occurring. In the early 1990s, there were reports of grazing at the 
site near Blind Spring; in 1992, heavy cattle grazing and trampling was 
reported (Barber, in litt. 1992b, p. 1), while 2 years later, in 1994, 
light use and minimal trampling by cattle was noted at this one site 
(Barber, in litt. 1994, p. 1). Currently, grazing is authorized within 
the Baking Powder Flat ACEC and is controlled through grazing permit 
terms and conditions (BLM 2007c, pp. 2.4-101; 2.4-106). BLM has 
indicated that some (undefined) areas of the ACEC can be ``heavily 
impacted'' by livestock grazing (BLM 2009a, p. 21). Over 70 percent of 
the ACEC is within the South Spring Valley Allotment (SNWA, in litt. 
2011, p. 37).

[[Page 54318]]

    However, the host plant is not known to be heavily grazed upon or 
preferred by livestock within the ACEC (Podborny 2012, pers. comm.). 
While livestock can and do move through the ACEC, concentrations in the 
butterfly's habitat do not occur as water is not readily available to 
them (Podborny 2012, pers. comm.). Thus, trampling of the host plant by 
livestock is not likely. The best available information indicates that 
the host plant, Eriogonum shockleyi, remains common in the Baking 
Powder Flat area (BLM 2009a, p. 20), and injury to or declines in the 
host plant species, larvae, or adults due to livestock grazing 
practices have not been documented. Activities involving grazing 
management within the Baking Powder Flat blue butterfly habitat would 
be addressed in consideration of the Ely District Record of Decision 
and Approved RMP (BLM 2008a), BLM's authority under Regulations on 
Grazing Administration Exclusive of Alaska, BLM's 6840 Manual (BLM 
2008b), Baking Powder Flat ACEC restrictions, and possibly NEPA (see 
our discussion of these authorities in the above analysis for the White 
River Valley skipper and below, with respect to the Baking Power Flat 
ACEC). We did not receive any information as a result of our 90-day 
petition finding notice, nor did we locate information indicating that 
livestock grazing is negatively impacting the habitat or populations of 
the Baking Powder Flat blue butterfly. Thus, the best available 
information does not indicate that livestock grazing is modifying the 
subspecies' habitat to the extent that it represents a threat to this 
subspecies now or in the future.
Nonnative Plant Invasion
    For general background information on nonnative plant invasion, 
please refer to the Nonnative Plant Invasion section under Factor A. 
The Present or Threatened Destruction, Modification, or Curtailment of 
Its Habitat or Range in the Five-Factor Evaluation for the White River 
Valley Skipper.
    The NNHP (2007, p. 42) indicates that a portion of the Baking 
Powder Flat playa/ephemeral pool/spring pool complex has been degraded, 
including by nonnative species invasion. The petition states that 
nonnative plant species invasion may be a potential threat to the 
Baking Powder Flat blue butterfly (B. Boyd, pers. comm. cited by 
WildEarth 2010, p. 14) though specific information to support this 
claim is not provided. Because numerous nonnative and invasive plant 
species occur in Nevada, it is likely that nonnative and invasive plant 
species occur to some extent, though this has not been quantified, 
within the ACEC and the habitat of the Baking Powder Flat blue 
butterfly. However, the issue of nonnative plant species invasion is 
not known to be a concern in the ACEC (Podborny 2012, pers. comm.). 
Though the Baking Powder Flat blue butterfly is associated with only 
one plant species for its life-history requirements, nonnative plant 
species do not appear to be competing with it and causing it to 
decline, as the host plant remains common in the Baking Powder Flat 
area and ACEC.
    Activities involving nonnative plant species management within the 
Baking Powder Flat blue butterfly habitat would be addressed in 
consideration of the Ely District Record of Decision and Approved RMP 
(BLM 2008a), BLM's authority under Regulations on Grazing 
Administration Exclusive of Alaska, the Plant Protection Act of 2000, 
BLM's programmatic EIS for vegetation treatments on BLM's administered 
lands in the western United States (BLM 2007a), BLM's 6840 Manual (BLM 
2008b), Baking Powder Flat ACEC restrictions, and possibly NEPA (see 
our discussion of these authorities above in the analysis of the White 
River Valley skipper, and below with respect to the Baking Power Flat 
ACEC). We did not receive any information as a result of our 90-day 
petition finding notice, nor did we locate information indicating that 
nonnative or invasive plant species are negatively impacting occupied 
habitat or populations of the Baking Powder Flat blue butterfly. 
Therefore, the best available information does not indicate that 
nonnative plant species are modifying the subspecies' habitat to the 
extent that it represents a threat to this subspecies now or in the 
future.
Agriculture
    The NNHP (2007, p. 42) indicates that a portion of the Baking 
Powder Flat playa/ephemeral pool/spring pool complex has been degraded 
or converted to other land uses, including agriculture. Although 
impacts of agriculture were mentioned in the petition as a potential 
threat to the Baking Powder Flat blue butterfly (WildEarth Guardians 
2010, p. 13), information was not provided to support this claim. 
Agriculture does not occur in the ACEC (Podborny 2012, pers. comm.). 
The best available information does not indicate agriculture is 
occurring in areas occupied by the Baking Powder Flat blue butterfly. 
We did not receive any information as a result of our 90-day petition 
finding notice, nor did we locate information that indicates 
agriculture is impacting occupied habitat or populations of the Baking 
Powder Flat blue butterfly. Thus, the best available information does 
not indicate that agriculture is modifying this subspecies' habitat to 
the extent that it represents a threat to Baking Powder Flat blue 
butterfly populations, their host plants, or nectar sources, now or in 
the future.
Recreation (Off-Highway Vehicles)
    Off-highway vehicle (OHV) impacts on wildlife can include habitat 
loss and fragmentation, patch size reduction, and an increase in the 
ratio of edge to the interior (U.S. Geological Survey (USGS) 2007, p. 
16). These effects can influence population dynamics, predator-prey 
relationships, and animal movements (e.g., dispersal, recolonization, 
gene flow). Even narrow roads and trails can create a barrier to animal 
movements. Additionally, OHV roads can facilitate range extensions or 
invasions of nonnative and opportunistic species, direct mortality 
through collisions, and nest and burrow damage or destruction, and they 
create noise. These factors can lead ultimately to reduced survivorship 
of a species.
    One study involving butterflies found wide highways did not affect 
movement with open populations (immigration and emigration continues to 
occur), but did slightly impact those with closed populations (Munguira 
and Thomas 1992, cited in USGS 2007, p. 18). Another study found some 
butterfly species may not attempt to fly across roads possibly due to 
the microclimate over roads (van der Zande 1980, cited in USGS 2007, p. 
18).
    In 2008, BLM designated a portion of Baking Powder Flat (13,640 
acres (ac)) (5,520 hectares (ha)) as the Baking Powder Flat ACEC to 
protect the Baking Powder Flat blue butterfly (72 FR 67748; 73 FR 
55867, September 26, 2008; BLM 2009a, p. 20). According to BLM (2009b, 
p. 20), an ACEC is defined as an area ``within the public lands where 
special management attention is required (when such areas are developed 
or used or where no development is required) to protect and prevent 
irreparable damage to important historic, cultural, or scenic values, 
fish and wildlife resources, or other natural systems or processes, or 
to protect life and safety from natural hazards.'' The Baking Powder 
Flat ACEC is managed as an ``avoidance area [* * *.] [G]ranting rights-
of-way (surface, subsurface, aerial) within the area will be avoided, 
but rights-of-way may be granted if there is minimal conflict with 
identified resource values and impacts can be mitigated.''
    Limited OHV use is authorized within the Baking Powder Flat ACEC on

[[Page 54319]]

designated roads and trails (72 FR 67748; BLM 2007c, pp. 2.4-101, 2.4-
106). Austin (1993, p. 7) and Austin et al. (in litt. 2000, p. 3) 
indicate that soil compaction or direct destruction of host plants from 
vehicles may impact the Baking Powder Flat blue butterfly, however, no 
additional information was provided to support this claim. A site visit 
to the occupied location near Blind Spring found evidence of one 
motorcycle going through the area as reported by a BLM employee in 1994 
(Barber in litt. 1994, p. 1). Today, with use limited to designated 
roads and trails, this recreational activity is not considered a 
concern in the ACEC (Podborny 2012, pers. comm.). Activities involving 
OHV use within the Baking Powder Flat blue butterfly habitat would be 
addressed in consideration of the Ely District Record of Decision and 
Approved RMP (BLM 2008a), BLM's 6840 Manual (BLM 2008b), Baking Powder 
Flat ACEC restrictions, and possibly NEPA (see also our discussion of 
several of these authorities in our analysis of the White River Valley 
skipper, above). We did not receive additional information as a result 
of our 90-day petition finding notice, nor did we locate information 
indicating that OHV use is damaging this subspecies' habitat. 
Consequently, the best available information does not indicate that OHV 
use is modifying this subspecies' habitat to the extent that it 
represents a threat to Baking Powder Flat blue butterfly populations or 
their habitats now or in the future.
Mining and Energy Exploration and Development, Power Lines
    The NNHP (2007, p. 42) indicates that a portion of the Baking 
Powder Flat playa/ephemeral pool/spring pool complex has been degraded 
or converted to other land uses, including energy development. Baking 
Powder Flat blue butterfly habitat was not identified within the study 
area for Southwest Intertie Project (BLM 1993, p. 3-65). The Baking 
Powder Flat blue butterfly was also not observed during wildlife 
surveys conducted for the One Nevada Transmission Line Project (BLM 
2010c, Appendix 3D, Table 2, pp. 1-5).
    There are closures or limits on mineral development within the 
Baking Powder Flat ACEC to protect the unique cultural values, and 
special status plants and animals, which includes the Baking Powder 
Flat blue butterfly (72 FR 67748; BLM 2007c, p. 2.4-101), and these 
types of projects are not occurring in the ACEC (Podborny 2012, pers. 
comm.). Additionally, actions involving mineral and energy development 
within Baking Powder Flat blue butterfly habitat would be addressed in 
consideration of the Ely District Record of Decision and Approved RMP 
(BLM 2008a), the FLPMA of 1976, the Mineral Leasing Act of 1920, BLM's 
6840 Manual (BLM 2008b), and NEPA (see our discussion of these 
authorities above in our analysis of the White River Valley skipper). 
The available information does not indicate that mineral and energy 
development are occurring in areas occupied by the Baking Powder Flat 
blue butterfly. We did not receive additional information as a result 
of our 90-day petition finding notice, nor did we locate information 
that indicates mining or energy development, or transmission line 
installation is impacting the Baking Powder Flat blue butterfly 
habitat. Thus, the best available information does not indicate that 
mining and energy development are modifying the subspecies' habitat or 
impacting Baking Powder Flat blue butterfly populations to an extent 
that they represent a threat to this subspecies now or in the future.
Plant Collection
    Plant collecting is authorized within the Baking Powder Flat ACEC 
(72 FR 67748; BLM 2007c, p. 2.4-101). Plant materials, including common 
species, require a permit to be collected (BLM 2007c, pp. 2.4-101; 2.4-
106). There have been no permit requests for collection of the host 
plant, Eriogonum shockleyi, for any purpose (Podborny 2012, pers. 
comm.). As indicated earlier, this host plant remains common in the 
Baking Powder Flat area (BLM 2009a, p. 20), and declines in this plant 
species have not been documented. Actions involving plant collection 
within Baking Powder Flat blue butterfly habitat would be addressed in 
consideration of the Ely District Record of Decision and Approved RMP 
(BLM 2008a), BLM's 6840 Manual (BLM 2008b), the Baking Powder Flat 
ACEC, and possibly the Plant Protection Act of 2000 and NEPA (see our 
discussion of these authorities above in the analysis of the White 
River Valley skipper). We did not receive any information as a result 
of our 90-day petition finding notice, nor did we locate information 
that indicates plant collecting in the ACEC, specifically for the host 
plant or in general, is occurring in occupied Baking Powder Flat blue 
butterfly habitat. Therefore, the best available information does not 
indicate that plant collecting is modifying the subspecies' habitat to 
an extent that it represents a threat to this subspecies now or in the 
future.
Climate Change
    Recent projections of climate change in the Great Basin over the 
next century include: Increased temperatures, with an increased 
frequency of extremely hot days in summer; more variable weather 
patterns and more severe storms; more winter precipitation in the form 
of rain, with potentially little change or decreases in summer 
precipitation; and earlier, more rapid snowmelt (U.S. Environmental 
Protection Agency 1998, pp. 1-4; Chambers and Pellant 2008, pp. 29-33). 
While the petition asserts that climate change may impact this 
subspecies (WildEarth Guardians 2010, p. 40), it is difficult to 
predict local climate change impacts, due to substantial uncertainty in 
trends of hydrological variables, limitations in spatial and temporal 
coverage of monitoring networks, and differences in the spatial scales 
of global climate models and hydrological models (Bates et al. 2008, p. 
3).
    We found no information on how climate change may impact the Baking 
Powder Flat blue butterfly's host plant, Eriogonum shockleyi. In 
general, increasing temperatures and drought frequency could impact the 
host plant by causing physiological stress, altering phenology, 
reducing recruitment events, and reducing seed establishment. However, 
at this time, it is difficult to predict local climate change impacts 
to Eriogonum Shockleyi and how individual plant species will react to 
climate change, especially for a species which grows in dry, warm sites 
and thus has adaptations for such conditions.
    Thus, while information indicates that climate change has the 
potential to affect vegetation and habitats used by the Baking Powder 
Flat blue butterfly in the Great Basin, there is much uncertainty 
regarding which habitat attributes could be affected, and the timing, 
magnitude, and rate of their change as it relates to this subspecies. 
The available information does not indicate that climate change is 
affecting occupied Baking Powder Flat blue butterfly habitat. We did 
not receive any further information as a result of our 90-day petition 
finding notice, nor did we locate specific information that indicates 
climate change is impacting Baking Powder Flat blue butterfly 
populations or their habitats. Thus, the best available information 
does not indicate that climate change is modifying the subspecies' 
habitat to an extent that it represents a threat to this subspecies now 
or in the future.
Summary of Factor A
    While several activities such as water development, fire, livestock 
grazing, nonnative species invasion, agriculture, mining and energy 
development may be

[[Page 54320]]

impacting a portion of the Baking Powder Flat wetland complex according 
to NNHP (2007 p. 42), available information does not indicate that 
these impacts are occurring in and negatively impacting occupied Baking 
Powder Flat blue butterfly habitat, which occurs outside of wetland 
areas. The available information does not indicate that these 
activities, or additional activities such as OHV use, plant collecting, 
or climate change, are negatively impacting Baking Powder Flat blue 
butterfly habitat or populations. The subspecies' larval host plant and 
adult nectar source (Eriogonum shockleyi) does not occur in wetland 
areas and is unlikely to be indirectly impacted by current or proposed 
water development activities. The host plant remains common in the 
Baking Powder Flat area (BLM 2009a, p. 20). In addition to the larval 
host plant not being a wetland species, any direct impacts to the plant 
through proposed SNWA water development facility construction 
activities, if approved, should be minor due to the commitment to 
implement avoidance, reduction, and mitigation measures. While 
information indicates that climate change has the potential to affect 
vegetation used by this subspecies, much uncertainty remains regarding 
which plant attributes may be affected, and the timing, magnitude, and 
rate of their change. We conclude based on the best scientific and 
commercial information available that the present or threatened 
destruction, modification, or curtailment of its habitat or range does 
not currently pose a threat to the Baking Powder Flat blue butterfly, 
nor is it likely to become a threat to the subspecies in the future.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    We are unaware of any studies analyzing impacts of removal of 
individuals from populations of the Baking Powder Flat blue butterfly. 
According to Austin (1998c, p. 550), 61 males and 41 females of this 
subspecies were collected between 1978 and 1980 at one site. No 
additional information is known about the numbers of specimens 
collected in the past, and we are not aware of any ongoing or current 
collecting of this subspecies. Given the relatively low number of 
individuals collected over this 3-year period, the length of time since 
the collections were made, and the lack of information about the 
relative impact to the population, the available information does not 
indicate that collection may be a threat to this subspecies.
    We found no information indicating that overutilization has led to 
the loss of populations or a significant reduction in numbers of 
individuals for this subspecies. Therefore, we conclude based on the 
best scientific and commercial information available that 
overutilization for commercial, recreational, scientific, or 
educational purposes does not currently pose a threat to the Baking 
Powder Flat blue butterfly, nor is it likely to become a threat to the 
subspecies in the future.

Factor C. Disease or Predation

    We found no information on the incidence of disease in the Baking 
Powder Flat blue butterfly.
    Predation by other species, such as birds or insects, on eggs, 
larvae, pupae, or adult Baking Powder Flat blue butterflies is assumed, 
but we found no information indicating that predation levels are any 
greater than naturally occurring levels typical of the biological 
community in which the Baking Powder Flat blue butterfly occurs.
    Available information does not indicate that there are impacts from 
disease or predation on the Baking Powder Flat blue butterfly. 
Therefore, we conclude based on the best scientific and commercial 
information available that disease or predation does not currently pose 
a threat to the Baking Powder Flat blue butterfly, nor is either likely 
to become a threat to the subspecies in the future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The discussion of existing regulatory mechanisms under Factor D for 
the White River Valley skipper is hereby incorporated into this 
discussion for the Baking Power Flat blue butterfly. As discussed above 
under Factor D for the White River Valley skipper, Nevada State law 
pertaining to wildlife does not offer protection to the Baking Powder 
Flat blue butterfly specifically because it is an invertebrate species 
not classified as wildlife. Although not protected by State wildlife 
law, the best available information, as discussed in Factor B, does not 
indicate that collection or other forms of overutilization is a threat 
to the Baking Powder Flat blue butterfly.
    A large portion of habitat for the Baking Powder Flat blue 
butterfly occurs on Federal lands administered by BLM. Numerous 
policies, guidance, and laws have been developed to assist the agency 
in management of these lands (see Factor D discussion under White River 
Valley skipper). BLM policies and guidance address species of concern, 
actions covered by RMPs, and regulatory authority for grazing and oil 
and gas leasing and operating activities. As discussed under Factor A, 
the best available information does not indicate that activities such 
as livestock grazing, nonnative plant control, mining and energy 
exploration and development, and recreational activities that are 
regulated by various policies, guidance, and laws on Federal lands are 
impacting Baking Powder Flat blue butterfly populations. After 
reviewing the best available commercial and scientific information, we 
conclude that the inadequacy of existing regulatory mechanisms does not 
currently pose a threat to the Baking Powder Flat blue butterfly, nor 
is it likely to become a threat to the subspecies in the future.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Potential other natural or manmade factors that may affect the 
continued existence of the Baking Powder Flat blue butterfly are 
discussed in this section and include: (1) Limited range and (2) small 
population size(s).
    For general background information on other natural or manmade 
factors which could affect the Baking Powder Flat blue butterfly, 
please refer to the discussion on limited range and population size 
under Factor E. Other Natural or Manmade Factors Affecting Its 
Continued Existence in the Five-Factor Evaluation for the White River 
Valley Skipper.
    The Baking Powder Flat blue butterfly is known from seven discrete 
areas in the Baking Powder Flat area in Spring Valley, in Lincoln and 
White Pine Counties, Nevada (Austin 1998c, p. 550; Austin and Leary 
2008, pp. 68-69). As indicated earlier, the host plant species, 
Eriogonum shockleyi, is common in Nevada and occurs in several other 
states. For the Baking Powder Flat blue butterfly, little information 
is available related to its distribution and numbers of populations, 
and no information is available about size of populations, loss of 
populations, if any, or population trends. Information pertaining to 
the aerial extent of habitat or populations is also not available. 
Available information does not include comprehensive surveys for this 
subspecies, though researchers have recommended these surveys to 
determine if additional populations exist. Without data to indicate 
population trends, it is difficult to support claims of adverse impacts 
to the Baking Powder Flat blue butterfly.
    We found no information on connections between chance events and 
population impacts for the Baking Powder Flat blue butterfly. This 
subspecies is distributed over several

[[Page 54321]]

areas in the Baking Powder Flat area, and as mentioned above, 
recommendations have been made for surveys to determine if it is more 
widespread than currently known. Potential impacts due to stochastic 
events are reduced because it occurs in several areas. In the absence 
of chance events connected to known populations, we do not consider 
restricted geographic range or small population numbers by themselves 
to be threats to this subspecies. The best available information does 
not indicate the Baking Powder Flat blue butterfly is negatively 
impacted by limited range or small population numbers. Therefore, we 
conclude based on the best available scientific and commercial 
information that other natural or manmade factors do not currently pose 
a threat to the Baking Powder Flat blue butterfly, nor are they likely 
to become a threat to the subspecies in the future.

Synergistic Interactions Between Threat Factors

    We have evaluated individual threats to the Baking Powder Flat blue 
butterfly. This subspecies faces potential threats from water 
development, fire, livestock grazing, nonnative plant invasion, 
agriculture, OHV use, mining and energy development, plant collection, 
climate change, limited range, and small population size. In 
considering whether the threats to a species may be so great as to 
warrant listing under the Act, we must look beyond the possible impacts 
of potential threats in isolation and consider the potential cumulative 
impacts of all of the threats facing a species.
    In making this finding, we considered whether there may be 
cumulative effects to the Baking Powder Flat blue butterfly from the 
combined impacts of the existing stressors such that even if each 
stressor individually does not result in population-level impacts, that 
cumulatively the effects may be significant. We considered whether the 
combined effects of water development and mining and energy development 
may result in a significant impact to the Baking Powder Flat blue 
butterfly because these potential impacts have the potential to result 
in some level of habitat loss. However, we conclude that synergistic 
effects between water development and mining and energy development are 
unlikely to result in a significant overall population impact to the 
Baking Powder Flat blue butterfly because the proposed water 
development construction footprint would be small, indirect impacts 
from the water development project are not likely, and BLM policies and 
mitigation measures ensure that impacts to this subspecies' habitat in 
the Baking Powder Flat ACEC will be minimized.
    Mining and energy development were not found to occur in the 
butterfly's habitat. If mining and energy development projects are 
proposed in the future, BLM policies and management offer protection 
through limitations for these types of activities within the ACEC. 
Livestock grazing, nonnative plant invasion, and OHV use could impact 
the Baking Powder Flat blue butterfly and its habitat. However, BLM 
policies and management provide terms and conditions for livestock 
grazing to protect resources; nonnative plant species invasion is not 
known to be a concern in the ACEC; and OHV use is limited to existing 
roads and trails in the ACEC.
    Therefore, we conclude that livestock grazing, nonnative plant 
species invasion, and OHV use impacts combined with potential impacts 
from water development and mining and energy development would not be 
of sufficient severity, frequency, or geographic scope to result in 
significant habitat impacts or cause population-level impacts to the 
Baking Powder Flat blue butterfly. Fire is unlikely to occur in Baking 
Powder Flat blue butterfly habitat due to the sandy soils and widely 
spaced vegetation being unable to support a fire. Agriculture and 
collection of the host plant species were not found to occur within 
this subspecies habitat and, therefore, will not have a cumulative 
impact on the Baking Powder Flat blue butterfly.
    Limited range and small population size could make the Baking 
Powder Flat blue butterfly more vulnerable to potential threats 
discussed above. However, we cannot conclude that synergistic effects 
between limited range and small population size and other potential 
threats are operative threats to the continued existence of the Baking 
Powder Flat blue butterfly given the lack of information on the range 
and population size of this butterfly. There is no information on 
population size or change in population abundance for the Baking Powder 
Flat blue butterfly, and the limited information on occurrence 
(distribution) is insufficient to define this butterfly's range.
    Synergistic interactions are possible between effects of climate 
change and effects of other stressors such as livestock grazing, 
nonnative plant invasion, and OHV use. Increases in carbon dioxide and 
temperature and changes in precipitation are likely to affect 
vegetation, and the Baking Powder Flat blue butterfly is closely 
associated with the presence of certain types of vegetation. However, 
it is difficult to project how climate change will affect vegetation 
because certain plant species may increase in cover while other species 
may decrease. Uncertainty about how different plant species will 
respond under climate change, combined with uncertainty about how 
changes in plant species composition would affect suitability of Baking 
Powder Flat blue butterfly habitat, make projecting possible 
synergistic effects of climate change on the Baking Powder Flat blue 
butterfly too speculative.

Finding for the Baking Powder Flat Blue Butterfly

    As required by the Act, we considered the five factors in assessing 
whether the Baking Powder Flat blue butterfly is an endangered or 
threatened species throughout all of its range. We examined the best 
scientific and commercial information available regarding the past, 
present, and future threats faced by this subspecies.
    Factors potentially affecting the Baking Powder Flat blue 
butterfly, including water development, fire, livestock grazing, 
nonnative species invasion, agriculture, mining and energy development, 
OHV, plant collecting, climate change, and limited range and small 
population size, are either limited in scope or lack documentation that 
they are occurring in occupied habitat and adversely impacting the 
subspecies. Though climate change may be affecting the Baking Powder 
Flat blue butterfly and its habitat and effects are likely to increase 
in the future, the available information does not support a 
determination that climate change has or will result in a population-
level impact to this subspecies. The available information does not 
indicate that overutilization, disease, or predation is a threat to the 
Baking Powder Flat blue butterfly. The available information also does 
not indicate that existing regulatory mechanisms are inadequate to 
protect the subspecies from potential threats. Furthermore, there is no 
evidence to suggest that the combined factors acting together are a 
threat to the Baking Powder Flat blue butterfly. Based on our review of 
the best scientific and commercial information available, we find these 
stressors, either singly or in combination with one another, are not 
threats to the Baking Powder Flat blue butterfly or its habitat.
    We found no information to indicate that threats are of sufficient 
imminence, intensity, or magnitude such that the Baking Powder Flat 
blue butterfly is in danger of extinction (endangered) or likely to 
become endangered within the

[[Page 54322]]

foreseeable future (threatened), throughout all of its range. 
Therefore, we find that listing the Baking Powder Flat blue butterfly 
as an endangered or threatened species throughout its range is not 
warranted.

Significant Portion of the Range

    Having determined that the Baking Powder Flat blue butterfly does 
not meet the definition of an endangered or a threatened species, we 
must next consider whether there are any significant portions of the 
range where the Baking Powder Flat blue butterfly is in danger of 
extinction or is likely to become endangered in the foreseeable future. 
The Act defines ``endangered species'' as any species which is ``in 
danger of extinction throughout all or a significant portion of its 
range,'' and ``threatened species'' as any species which is ``likely to 
become an endangered species within the foreseeable future throughout 
all or a significant portion of its range.'' 16 U.S.C. 1532(6) and 
1532(20). The definition of ``species'' is also relevant to this 
discussion. The Act defines ``species'' as follows: ``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). The 
phrase ``significant portion of its range'' (SPR) is not defined by the 
statute, and we have never addressed in our regulations: (1) The 
consequences of a determination that a species is either endangered or 
likely to become so throughout a significant portion of its range, but 
not throughout all of its range; or (2) what qualifies a portion of a 
range as ``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountains gray wolf (74 FR 15123, April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the Gunnison's prairie dog (73 FR 6660, February 5, 
2008). The Service had asserted in both of these determinations that, 
under the Act, it had authority, in effect, to protect only some 
members of a ``species,'' as defined by the Act (i.e., species, 
subspecies, or DPS). Both courts ruled that the determinations were 
arbitrary and capricious on the grounds that this approach violated the 
plain and unambiguous language of the Act. The courts concluded that 
reading the SPR language to allow protecting only a portion of a 
species' range is inconsistent with the Act's definition of 
``species.'' The courts concluded that once a determination is made 
that a species (i.e., species, subspecies, or DPS) meets the definition 
of ``endangered species'' or ``threatened species,'' it must be placed 
on the list in its entirety and the Act's protections applied 
consistently to all members of that species throughout its range 
(subject to modification of protections through special rules under 
sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing. Thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be endangered or threatened throughout all 
of its range, or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout an SPR, it, the species, is an ``endangered 
species.'' The same analysis applies to ``threatened species.'' Based 
on this interpretation and supported by existing case law, the 
consequence of finding that a species is endangered or threatened in 
only a significant portion of its range is that the entire species 
shall be listed as endangered or threatened, respectively, and the 
Act's protections shall be applied across the species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the SPR phrase as providing an independent basis for listing is the 
best interpretation of the Act because it is consistent with the 
purposes and the plain meaning of the key definitions of the Act; it 
does not conflict with established past agency practice (i.e., prior to 
the 2007 Solicitor's Opinion), as no consistent, long-term agency 
practice has been established; and it is consistent with the judicial 
opinions that have most closely examined this issue. Having concluded 
that the phrase ``significant portion of its range'' provides an 
independent basis for listing and protecting the entire species, we 
next turn to the meaning of ``significant'' to determine the threshold 
for when such an independent basis for listing exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that, 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether, without that portion, the 
representation, redundancy, or resiliency of the species would be so 
impaired that the species would have an increased vulnerability to 
threats to the point that the overall species would be in danger of 
extinction (i.e., would be ``endangered''). Conversely, we would

[[Page 54323]]

not consider the portion of the range at issue to be ``significant'' if 
there is sufficient resiliency, redundancy, and representation 
elsewhere in the species' range that the species would not be in danger 
of extinction throughout its range if the population in that portion of 
the range in question became extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that, without that portion, 
the species would be in danger of extinction) establishes a threshold 
that is relatively high. On the one hand, given that the consequences 
of finding a species to be endangered or threatened in an SPR would be 
listing the species throughout its entire range, it is important to use 
a threshold for ``significant'' that is robust. It would not be 
meaningful or appropriate to establish a very low threshold whereby a 
portion of the range can be considered ``significant'' even if only a 
negligible increase in extinction risk would result from its loss. 
Because nearly any portion of a species' range can be said to 
contribute some increment to a species' viability, use of such a low 
threshold would require us to impose restrictions and expend 
conservation resources disproportionately to conservation benefit: 
Listing would be rangewide, even if only a portion of the range of 
minor conservation importance to the species is imperiled. On the other 
hand, it would be inappropriate to establish a threshold for 
``significant'' that is too high. This would be the case if the 
standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the SPR phrase independent meaning, as the 
Ninth Circuit held in Defenders of Wildlife v. Norton, 258 F.3d 1136 
(9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the threshold so high that the phrase ``in a 
significant portion of its range'' loses independent meaning. 
Specifically, we have not set the threshold as high as it was under the 
interpretation presented by the Service in the Defenders litigation. 
Under that interpretation, the portion of the range would have to be so 
important that current imperilment there would mean that the species 
would be currently imperiled everywhere. Under the definition of 
``significant'' used in this finding, the portion of the range need not 
rise to such an exceptionally high level of biological significance. 
(We recognize that if the species is imperiled in a portion that rises 
to that level of biological significance, then we should conclude that 
the species is in fact imperiled throughout all of its range, and that 
we would not need to rely on the SPR language for such a listing.) 
Rather, under this interpretation, we ask whether the species would be 
endangered everywhere without that portion (i.e., if that portion were 
completely extirpated). In other words, the portion of the range need 
not be so important that even the species being in danger of extinction 
in that portion would be sufficient to cause the species in the 
remainder of the range to be endangered; rather, the complete 
extirpation (in a hypothetical future) of the species in that portion 
would be required to cause the species in the remainder of the range to 
be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it might be more efficient for us to address 
the significance question first or the status question first. Thus, if 
we determine that a portion of the range is not ``significant,'' we do 
not need to determine whether the species is endangered or threatened 
there; if we determine that the species is not endangered or threatened 
in a portion of its range, we do not need to determine if that portion 
is ``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the Baking Powder Flat blue 
butterfly to determine if there is any apparent geographic 
concentration of the primary stressors potentially affecting the 
subspecies including water development, fire, livestock grazing, 
nonnative species invasion, agriculture, mining and energy development, 
OHV, plant collecting, climate change, and limited range and small 
population size. On the basis of our review, we found no geographic 
concentration of threats either on public or private lands to suggest 
that the Baking Powder Flat blue butterfly may be in danger of 
extinction in that portion of its range. We found no area within the 
range of the Baking Powder Flat blue butterfly where the potential 
threats are significantly concentrated or substantially greater than in 
other portions of its range. We also found that lost historical range 
does not constitute a significant portion of the range for the Baking 
Powder Flat blue butterfly because there is no information indicating 
that there has been a range contraction for this subspecies. Therefore, 
we find factors affecting the subspecies are essentially uniform 
throughout its range, indicating no portion of the butterfly's range 
warrants further consideration of possible status as an endangered or 
threatened species under the Act.
    We found no information to indicate that the Baking Powder Flat 
blue butterfly is in danger of extinction now, nor is it likely to 
become endangered within the foreseeable future, throughout all or a 
significant portion of its range. Therefore, listing the Baking Powder 
Flat blue butterfly as an endangered or threatened species under the 
Act is not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the Baking Powder Flat blue butterfly to our 
Nevada Fish and Wildlife Office (see ADDRESSES section) whenever it 
becomes available. New information will help us monitor the Baking 
Powder Flat blue butterfly and encourage its conservation. If an 
emergency situation develops for the Baking Powder Flat blue butterfly 
or any other species, we will act to provide immediate protection.

[[Page 54324]]

Species Information for the Bleached Sandhill Skipper

Taxonomy and Species Description

    We accept the characterization of the bleached sandhill skipper 
(Polites sabuleti sinemaculata) as a valid subspecies based on its 
description by Austin (1987, pp. 7-8). This subspecies is in the 
Hesperiidae family (Austin 1998a, p. 838). The male's wingspan ranges 
from 0.47 to 0.53 in (11.9-13.4 mm). The upperside is bright golden-
orange with a black stigma on the primaries. The dark margin of the 
primaries is absent to faint. The terminal line is black. Wing fringes 
are the same as the wing color. The secondaries do not have an outer 
marginal border. The black along the costal (leading edge) margin is 
narrow, and the base of the wing is lightly dusted with black. The 
terminal line and wing fringes are like they are on the primaries. The 
underside of the wing is paler than the upperside. The black of the 
primaries is restricted to the base of the cell and along the posterior 
margin. The secondaries have a faint cobweb pattern (Austin 1987, pp. 
7-8). The female's wingspan ranges from 0.52 to 0.59 in (13.1-15.0 mm). 
The upperside of the wing is a pale yellow-orange. The postmedial (on 
the wing, just past the middle) area of the primaries is whitish-
yellow. The terminal line is dark gray, and fringes are grayish on the 
primaries and white on the secondaries. The underside is paler than on 
the male. The postmedial areas of the primaries and the postmedian band 
and secondaries are ghostly white (Austin 1987, p. 8). Please refer to 
Austin (1987, p. 8) for a more detailed description of this subspecies.

Distribution and Habitat

    The bleached sandhill skipper is known from one location (Baltazor 
Hot Spring) located west of Denio Junction, Humboldt County, located in 
northwestern Nevada (Austin 1987, p. 8; Austin et al., in litt. 2000, 
p. 4; NNHP 2010; B. Boyd, pers. comm. cited in WildEarth Guardians 
2010, p. 15) (on BLM and private lands). Austin (1987, p. 8) indicates 
that other areas of the Baltazor Hot Spring drainage system need to be 
investigated for possible other populations. The area is a salt flat 
near a hot spring and is densely covered with Distichlis spicata (salt 
grass) (Austin 1987, p. 8), this subspecies' possible host plant (see 
Biology section). The size of the known occupied site or the extent of 
this subspecies' host plant(s), or host plant abundance, has not been 
reported.

Biology

    Distichlis spicata may serve as the larval host plant (Austin 1987, 
p. 8); this species is a perennial grass (http://www.plants.usda.gov, 
accessed April 24, 2012) and is common and widespread in Nevada 
(Kartesz, 1987, p. 1611). This plant can be found in wetland and non-
wetland areas in Nevada (Reed 1988, p. 24). It is common and can be 
found throughout most of the United States (http://www.plants.usda.gov, 
accessed April 24, 2012). In the western United States, it can be found 
in Washington, Oregon, California, Idaho, Montana, Nevada, Utah, 
Arizona, and New Mexico (Kartesz, 1987, p. 1611; http://www.plants.usda.gov, accessed April 24, 2012).
    Adults have been seen nectaring on white and yellow composites 
(Asteraceae) (Sunflower family) (Austin 1987, p. 8), but specific 
nectar plant species are not identified. It is possible that adults 
nectar on a variety of plants that are in flower during their flight 
period. Adults are known to fly during late August to mid September, 
and it is unknown if earlier broods occur (Austin 1987, p. 8; Austin et 
al., in litt. 2000, p. 4).
    There is little biological information available at the subspecies 
level, but some inferences can be made from biological information from 
related species at the species level. Information for the saltgrass 
skipper (Polites sabuleti) indicates eggs are pale bluish-green, 
turning cream-colored; eggs are laid singly on the host plant or other 
nearby plants or soil (Scott 1986, p. 443). Larvae eat leaves, and they 
live in tied-leaf nests (Scott 1986, p. 443). Males perch in low grassy 
areas during the day seeking females (Scott 1986, p. 444).
    According to the petition, thousands of bleached sandhill skippers 
have been seen in the past (A. Warren, pers. comm. cited in WildEarth 
Guardians 2010, p. 15), but the population appears to have declined 2-3 
years ago (B. Boyd, pers. comm. cited in WildEarth Guardians 2010, p. 
15). The cause or potential cause of this apparent decline is not 
reported in the petition. The available information does not indicate 
whether a population decline, if accurate, is unusual or not as 
butterfly populations are highly dynamic from year to year (Weiss et 
al. 1997, p. 2). The best available information does not include 
surveys documenting population size, number of extirpated populations 
or sites, if any, or population trends (other than that mentioned 
above).

Five-Factor Evaluation for the Bleached Sandhill Skipper

    Information pertaining to the bleached sandhill skipper in relation 
to the five factors provided in section 4(a)(1) of the Act is discussed 
below.

Factor A. The Present or Threatened Destruction, Modification, or 
Curtailment of Its Habitat or Range

    Potential factors that may affect the habitat or range of the 
bleached sandhill skipper are discussed in this section, including: (1) 
Water development, (2) livestock grazing, (3) energy development, and 
(4) climate change.
Water Development
    For general background information on water development, please 
refer to the Water Development section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    Austin et al. (in litt. 2000, p. 4) state that the bleached 
sandhill skipper could be impacted by water table changes, but specific 
information is not provided to support this claim. The Baltazor Meadow-
Continental Lake wetland area is estimated to have had 20 percent of 
its wetland area degraded or converted to other land uses, such as by 
water development (NNHP 2007, p. 36). The Baltazor Meadow-Continental 
Lake wetland area includes the Baltazor Hot Spring where the bleached 
sandhill skipper is known to occur and an additional area, Continental 
Lake, located to the south where the bleached sandhill skipper is not 
known to occur. The NNHP (2007) does not delineate these wetland areas 
on a map or define them in terms of acreage; therefore, the amount of 
bleached sandhill skipper habitat that may occur within these areas and 
may be impacted by various activities is not indicated. The extent to 
which the various land use practices have degraded or converted these 
areas is also not individually delineated or quantified by NNHP (2007). 
Therefore, we cannot determine the amount of overlap between the 
estimated wetland impacts identified by the NNHP and the distribution 
of the bleached sandhill skipper. Bleached sandhill skipper habitat 
will not be impacted by the SNWA water development project because the 
project is proposed in southern and eastern Nevada and in groundwater 
basins not connected to the basin where this skipper occurs.
    While it is likely that human water demands have impacted this 
drainage system over the decades, pumping of

[[Page 54325]]

the Baltazor Hot Spring does not currently occur (Lawson 2012, per. 
comm.). The best available information does not indicate that changes 
due to water development have occurred in the area occupied by the 
bleached sandhill skipper and are negatively impacting the habitat of 
this subspecies. Actions regarding water management in bleached 
sandhill skipper habitat in the future would be addressed in 
consideration of Nevada water law. We did not receive any additional 
information as a result of our 90-day petition finding notice, nor did 
we locate information that indicates water development is impacting the 
subspecies' habitat. Therefore, the best available information does not 
indicate that water development is modifying the subspecies' habitat to 
an extent that it represents a threat to the bleached sandhill skipper 
population now or in the future.
Livestock Grazing
    For general background information on livestock grazing, please 
refer to the Livestock Grazing section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    A portion of the Baltazor Meadow-Continental Lake wetland area has 
been identified as degraded or converted to other land uses, including 
livestock grazing (NNHP 2007, p. 36). The Baltazor Hot Spring and most 
of the vegetation associated with bleached sandhill skipper habitat 
(approximately 100 ac (40.5 ha)) is located within the Continental 
Pasture of the Pueblo Mountain Allotment on BLM-administered lands 
(Lawson 2012, pers. comm.). The pasture is on a 3-year rotation with 
cattle grazing occurring 2 out of every 3 years for 1 month in August; 
the permittee usually does not graze the entire month (Lawson 2012, 
pers. comm.). The area is not heavily grazed, and the habitat looks to 
be in good condition (Lawson 2012, pers. comm.). The possible larval 
host plant, Distichlis spicata, is common here and widespread in 
Nevada. The Asteraceae Family is a large plant family comprising 
numerous species, several of which the adults may be using as nectar 
sources. The best available information does not indicate a decline in 
either the possible larval host plant or probable adult nectar source 
populations within the bleached sandhill skipper's habitat due to 
livestock grazing.
    Actions involving livestock grazing within bleached sandhill 
skipper habitat are addressed in consideration of the Winnemucca 
District Record of Decision and Approved RMP (BLM 2010a) (see Factor D 
discussion under White River Valley skipper), BLM's authority under 
Regulations on Grazing Administration Exclusive of Alaska, BLM's 6840 
Manual (BLM 2008b), and possibly NEPA (see our discussion of these 
authorities above, under White River Valley skipper). We did not 
receive any information as a result of our 90-day petition finding 
notice, nor did we locate information indicating that livestock grazing 
is negatively impacting the habitat or the known population of the 
bleached sandhill skipper. Thus, the best available information does 
not indicate that livestock grazing is modifying the subspecies' 
habitat to the extent that it represents a threat to this subspecies 
now or in the future.
Energy Development
    For general background information on energy development, please 
refer to the Energy Development section under Factor A. The Present or 
Threatened Destruction, Modification, or Curtailment of Its Habitat or 
Range in the Five-Factor Evaluation for the White River Valley Skipper.
    A portion of the Baltazor Meadow-Continental Lake wetland area has 
been identified as degraded or converted to other land uses, including 
energy development (NNHP 2007, p. 36). Energy development is not 
occurring within the bleached sandhill skipper habitat (Lawson 2012, 
pers. comm.). Any actions involving energy development within bleached 
sandhill skipper habitat would be addressed in consideration of the 
Winnemucca District Record of Decision and Approved RMP (BLM 2010a), 
the FLPMA of 1976, BLM's 6840 Manual (BLM 2008b), and NEPA (see our 
discussion of these authorities above under White River Valley 
skipper). We did not receive any information as a result of our 90-day 
petition finding notice, nor did we locate information indicating that 
energy development is negatively impacting the bleached sandhill 
skipper population or its habitat. Thus, the best available information 
does not indicate that energy development is modifying the subspecies' 
habitat to the extent that it represents a threat to this subspecies 
now or in the future.
Climate Change
    For general background information on climate change, please refer 
to the Climate Change section under Factor A. The Present or Threatened 
Destruction, Modification, or Curtailment of Its Habitat or Range in 
the Five-Factor Evaluation for the White River Valley Skipper.
    It is difficult to predict local climate change impacts, due to 
substantial uncertainty in trends of hydrological variables, 
limitations in spatial and temporal coverage of monitoring networks, 
and differences in the spatial scales of global climate models and 
hydrological models (Bates et al. 2008, p. 3). We found no information 
on how climate change may impact the bleached sandhill skipper's 
potential host plant, Distichlis spicata, or adult nectar sources. In 
general, increasing temperatures and drought frequency, more winter 
precipitation in the form of rain, possible decreases in summer rain, 
and earlier, rapid snowmelt could impact the host plant by causing 
physiological stress, altering phenology, reducing recruitment events, 
and reducing seed establishment. However, at this time, it is difficult 
to predict local climate change impacts to Distichlis spicata and how 
individual plant species will react to climate change, especially for a 
species which is common and grows in both wet and dry areas. Thus, 
while information indicates that climate change has the potential to 
affect vegetation and habitats used by the bleached sandhill skipper in 
the Great Basin, there is much uncertainty regarding which habitat 
attributes could be affected, and the timing, magnitude, and rate of 
their change as it relates to this subspecies.
    The best available information does not indicate that climate 
change is impacting occupied bleached sandhill skipper habitat. We did 
not receive any information as a result of our 90-day petition finding 
notice, nor did we locate specific information that indicates climate 
change is negatively impacting bleached sandhill skipper habitat. 
Therefore, the best available information does not indicate that 
climate change is modifying the subspecies' habitat to the extent that 
it represents a threat to this subspecies now or in the future.
Summary of Factor A
    While a few activities such as water development and livestock 
grazing may be impacting a portion of the Baltazor Meadow-Continental 
Lake wetland area, the available information does not indicate that 
these activities or climate change are negatively impacting the 
bleached sandhill skipper population or its habitat. Therefore, we 
conclude based on the best scientific and commercial information 
available that the present or threatened destruction, modification, or 
curtailment of its habitat or range does not currently pose

[[Page 54326]]

a threat to the bleached sandhill skipper, now or is it likely to 
become a threat to the subspecies in the future.

Factor B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    For general background information on overutilization, please refer 
to the discussion on collecting under Factor B. Overutilization for 
Commercial, Recreational, Scientific, or Educational Purposes in the 
Five-Factor Evaluation for the White River Valley Skipper.
    We are unaware of any studies analyzing impacts of removal of 
individuals from populations of the bleached sandhill skipper. 
According to Austin (1987, p. 8), 27 males and 14 females were 
collected between 1984 and 1985 at one site. No additional information 
is known about the numbers of specimens collected in the past, and we 
are not aware of any ongoing or current collecting of this subspecies. 
Given the low number of individuals collected over this 2-year period, 
the length of time since the collections were made, and the lack of 
information about the relative impact to the populations, the available 
information does not indicate that collection may be a threat to this 
subspecies.
    We found no information indicating that overutilization has led to 
the loss of populations or a significant reduction in numbers of 
individuals for this subspecies. Therefore, we conclude based on the 
best scientific and commercial information available that 
overutilization for commercial, recreational, scientific, or 
educational purposes does not currently pose a threat to the bleached 
sandhill skipper, nor is it likely to become a threat to the subspecies 
in the future.

Factor C. Disease or Predation

    We found no information on the incidence of disease in the bleached 
sandhill skipper.
    We assume that predation by other species, such as birds or 
insects, on eggs, larvae, pupae, or adult bleached sandhill skippers 
occurs, but we found no information indicating that predation levels 
are any greater than naturally occurring levels typical of the 
biological community in which the bleached sandhill skipper occurs.
    Available information does not indicate that there are impacts from 
disease or predation on the bleached sandhill skipper. Therefore, we 
conclude based on the best scientific and commercial information 
available that disease or predation does not currently pose a threat to 
the bleached sandhill skipper, nor is either likely to become a threat 
to the subspecies in the future.

Factor D. The Inadequacy of Existing Regulatory Mechanisms

    The discussion of existing regulatory mechanisms under Factor D for 
the White River Valley skipper is hereby incorporated into this 
discussion for the bleached sandhill skipper. As discussed above under 
Factor D for the White River Valley skipper, Nevada State law 
pertaining to wildlife does not offer protection to the bleached 
sandhill skipper specifically because it is an invertebrate species not 
classified as wildlife. Although not protected by State wildlife law, 
the best available information, as discussed in Factor B, does not 
indicate that collection or other forms of overutilization is a threat 
to the bleached sandhill skipper.
    A large portion of habitat for the bleached sandhill skipper occurs 
on Federal lands administered by BLM. Numerous policies, guidance, and 
laws have been developed to assist the agency in management of these 
lands (see Factor D discussion under White River Valley skipper). BLM 
policies and guidance address species of concern, actions covered by 
RMPs, and regulatory authority for grazing and oil and gas leasing and 
operating activities. As discussed under Factor A, the best available 
information does not indicate that activities such as livestock grazing 
and mining and energy development that are regulated by various 
policies, guidance, and laws on Federal lands are impacting the habitat 
of the bleached sandhill skipper. We conclude based on the best 
available commercial and scientific information that the inadequacy of 
existing regulatory mechanisms does not pose a threat to the bleached 
sandhill skipper, nor is it likely to become a threat to the subspecies 
in the future.

Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence

    Potential other natural or manmade factors that may affect the 
continued existence of the bleached sandhill skipper are discussed in 
this section and include: (1) Limited range and (2) small population 
size(s).
    For general background information on other natural or manmade 
factors which could affect the bleached sandhill skipper, please refer 
to the discussion on limited distribution and population size under 
Factor E. Other Natural or Manmade Factors Affecting Its Continued 
Existence in the Five-Factor Evaluation for the White River Valley 
Skipper.
    The bleached sandhill skipper is currently known from only one area 
(Baltazor Hot Spring) near Denio Junction, Humboldt County, Nevada (see 
Distribution and Habitat section). However, Austin (1987, p. 8) 
indicates that other areas of the Baltazor Hot Springs drainage system 
need to be investigated for possible other populations. The petition 
reports that although thousands had been seen in the past, a decline 
appears to have occurred 2-3 years ago (A. Warren, pers. comm. and B. 
Boyd, pers. comm., cited in WildEarth Guardians 2010, p. 15), but 
details regarding this decline or a reason(s) for it are not provided 
in the petition. It is unknown whether or not this decline, if 
accurate, can be attributed to the normal natural fluctuations of 
butterfly populations. Butterfly populations are highly dynamic, and 
numbers and distribution can be highly variable year to year (Weiss et 
al. 1997, p. 2).
    Little information is available related to population numbers, 
size, or trends for the bleached sandhill skipper. Information 
pertaining to the aerial extent of habitat or populations is not 
available. The available information does not include comprehensive 
surveys for this subspecies though researchers have recommended these 
surveys to determine if additional populations exist. Without data to 
indicate population trends, it is difficult to support claims of 
adverse impacts to the bleached sandhill skipper. We found no 
information on connections between chance events and population impacts 
for the bleached sandhill skipper. In the absence of chance events 
connected to known populations, we do not consider restricted 
geographic range or small population numbers by themselves to be 
threats to a species. The best available information does not indicate 
that the bleached sandhill skipper is negatively impacted by limited 
range or small population numbers. Therefore, we conclude based on the 
best available scientific and commercial information that other natural 
or manmade factors do not currently pose a threat to the bleached 
sandhill skipper, nor are they likely to become a threat to the 
subspecies in the future.

Synergistic Interactions Between Threat Factors

    We have evaluated individual threats to the bleached sandhill 
skipper. This subspecies faces potential threats from water 
development, livestock grazing, energy development, climate change, 
limited range, and small population

[[Page 54327]]

size. In considering whether the threats to a species may be so great 
as to warrant listing under the Act, we must look beyond the possible 
impacts of potential threats in isolation and consider the potential 
cumulative impacts of all of the threats facing a species.
    In making this finding, we considered whether there may be 
cumulative effects to the bleached sandhill skipper from the combined 
impacts of the existing stressors such that even if each stressor 
individually does not result in population-level impacts, that 
cumulatively the effects may be significant. We considered whether the 
combined effects of water development and energy development may result 
in a significant impact to the bleached sandhill skipper because these 
potential impacts have the potential to result in some level of habitat 
loss. However, we conclude that synergistic effects between water 
development and energy development will not result in a significant 
overall population impact to the bleached sandhill skipper because 
these activities have not been found to occur within this subspecies' 
habitat. While livestock grazing could impact habitat of the bleached 
sandhill skipper, BLM policies and management provide terms and 
conditions for livestock grazing to protect resources, and we conclude 
that livestock grazing is not of sufficient severity, frequency, or 
geographic scope to result in significant habitat impacts or cause 
population-level impacts to the bleached sandhill skipper.
    Limited range and small population size could make the bleached 
sandhill skipper more vulnerable to potential threats discussed above. 
However, we cannot conclude that synergistic effects between limited 
range and small population size and other potential threats are 
operative threats to the continued existence of the bleached sandhill 
skipper given the lack of information on the range and population size 
of this butterfly. There is no information on population size or change 
in population abundance for the bleached sandhill skipper, and the 
limited information on occurrence (distribution) is insufficient to 
define this skipper's range.
    Synergistic interactions are possible between effects of climate 
change and effects of other stressors such as livestock grazing. 
Increases in carbon dioxide and temperature and changes in 
precipitation are likely to affect vegetation, and the bleached 
sandhill skipper is closely associated with the presence of vegetation. 
However, it is difficult to project how climate change will affect 
vegetation because certain plant species may increase in cover while 
other species may decrease. Uncertainty about how different plant 
species will respond under climate change, combined with uncertainty 
about how changes in plant species composition would affect suitability 
of bleached sandhill skipper habitat, make projecting possible 
synergistic effects of climate change on the bleached sandhill skipper 
too speculative.

Finding for the Bleached Sandhill Skipper

    As required by the Act, we considered the five factors in assessing 
whether the bleached sandhill skipper is an endangered or threatened 
species throughout all of its range. We examined the best scientific 
and commercial information available regarding the past, present, and 
future threats faced by this subspecies.
    Factors potentially affecting the bleached sandhill skipper 
including water development, livestock grazing, energy development, or 
climate change, and limited range and small population size, are either 
limited in scope or lack documentation that they are occurring in 
occupied habitat and adversely impacting the subspecies. Though climate 
change may be affecting the bleached sandhill skipper and its habitats, 
and effects are likely to increase in the future, the available 
information does not support a determination that climate change will 
have a population-level impact on this subspecies. The available 
information also does not indicate that overutilization, disease, or 
predation is negatively impacting the bleached sandhill skipper. There 
is also no indication that existing regulatory mechanisms are 
inadequate to protect the subspecies from potential threats. 
Furthermore, there is no evidence to suggest that the combined 
stressors acting together are a threat to the bleached sandhill 
skipper. Based on our review of the best scientific and commercial 
information available, we find these stressors, either singly or in 
combination with one another, are not threats to the bleached sandhill 
skipper.
    We found no information to indicate that threats are of sufficient 
imminence, intensity, or magnitude such that the bleached sandhill 
skipper is in danger of extinction (endangered) or likely to become 
endangered within the foreseeable future (threatened), throughout all 
of its range. Therefore, we find that listing the bleached sandhill 
skipper as an endangered or threatened species is not warranted 
throughout its range.

Significant Portion of the Range

    Having determined that the bleached sandhill skipper does not meet 
the definition of an endangered or a threatened species, we must next 
consider whether there are any significant portions of the range where 
the bleached sandhill skipper is in danger of extinction or is likely 
to become endangered in the foreseeable future. The Act defines 
``endangered species'' as any species which is ``in danger of 
extinction throughout all or a significant portion of its range,'' and 
``threatened species'' as any species which is ``likely to become an 
endangered species within the foreseeable future throughout all or a 
significant portion of its range.'' 16 U.S.C. 1532(6) and 1532(20). The 
definition of ``species'' is also relevant to this discussion. The Act 
defines ``species'' as follows: ``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). The phrase ``significant portion of 
its range'' (SPR) is not defined by the statute, and we have never 
addressed in our regulations: (1) The consequences of a determination 
that a species is either endangered or likely to become so throughout a 
significant portion of its range, but not throughout all of its range; 
or (2) what qualifies a portion of a range as ``significant.''
    Two recent district court decisions have addressed whether the SPR 
language allows the Service to list or protect less than all members of 
a defined ``species'': Defenders of Wildlife v. Salazar, 729 F. Supp. 
2d 1207 (D. Mont. 2010), concerning the Service's delisting of the 
Northern Rocky Mountains gray wolf (74 FR 15123, April 2, 2009); and 
WildEarth Guardians v. Salazar, 2010 U.S. Dist. LEXIS 105253 (D. Ariz. 
September 30, 2010), concerning the Service's 2008 finding on a 
petition to list the Gunnison's prairie dog (73 FR 6660, February 5, 
2008). The Service had asserted in both of these determinations that, 
under the Act, it had authority, in effect, to protect only some 
members of a ``species,'' as defined by the Act (i.e., species, 
subspecies, or DPS). Both courts ruled that the determinations were 
arbitrary and capricious on the grounds that this approach violated the 
plain and unambiguous language of the Act. The courts concluded that 
reading the SPR language to allow protecting only a portion of a 
species' range is inconsistent with the Act's definition of

[[Page 54328]]

``species.'' The courts concluded that once a determination is made 
that a species (i.e., species, subspecies, or DPS) meets the definition 
of ``endangered species'' or ``threatened species,'' it must be placed 
on the list in its entirety and the Act's protections applied 
consistently to all members of that species throughout its range 
(subject to modification of protections through special rules under 
sections 4(d) and 10(j) of the Act).
    Consistent with that interpretation, and for the purposes of this 
finding, we interpret the phrase ``significant portion of its range'' 
in the Act's definitions of ``endangered species'' and ``threatened 
species'' to provide an independent basis for listing. Thus there are 
two situations (or factual bases) under which a species would qualify 
for listing: A species may be endangered or threatened throughout all 
of its range, or a species may be endangered or threatened in only a 
significant portion of its range. If a species is in danger of 
extinction throughout an SPR, it, the species, is an ``endangered 
species.'' The same analysis applies to ``threatened species.'' Based 
on this interpretation and supported by existing case law, the 
consequence of finding that a species is endangered or threatened in 
only a significant portion of its range is that the entire species 
shall be listed as endangered or threatened, respectively, and the 
Act's protections shall be applied across the species' entire range.
    We conclude, for the purposes of this finding, that interpreting 
the SPR phrase as providing an independent basis for listing is the 
best interpretation of the Act because it is consistent with the 
purposes and the plain meaning of the key definitions of the Act; it 
does not conflict with established past agency practice (i.e., prior to 
the 2007 Solicitor's Opinion), as no consistent, long-term agency 
practice has been established; and it is consistent with the judicial 
opinions that have most closely examined this issue. Having concluded 
that the phrase ``significant portion of its range'' provides an 
independent basis for listing and protecting the entire species, we 
next turn to the meaning of ``significant'' to determine the threshold 
for when such an independent basis for listing exists.
    Although there are potentially many ways to determine whether a 
portion of a species' range is ``significant,'' we conclude, for the 
purposes of this finding, that the significance of the portion of the 
range should be determined based on its biological contribution to the 
conservation of the species. For this reason, we describe the threshold 
for ``significant'' in terms of an increase in the risk of extinction 
for the species. We conclude that a biologically based definition of 
``significant'' best conforms to the purposes of the Act, is consistent 
with judicial interpretations, and best ensures species' conservation. 
Thus, for the purposes of this finding, and as explained further below, 
a portion of the range of a species is ``significant'' if its 
contribution to the viability of the species is so important that, 
without that portion, the species would be in danger of extinction.
    We evaluate biological significance based on the principles of 
conservation biology using the concepts of redundancy, resiliency, and 
representation. Resiliency describes the characteristics of a species 
and its habitat that allow it to recover from periodic disturbance. 
Redundancy (having multiple populations distributed across the 
landscape) may be needed to provide a margin of safety for the species 
to withstand catastrophic events. Representation (the range of 
variation found in a species) ensures that the species' adaptive 
capabilities are conserved. Redundancy, resiliency, and representation 
are not independent of each other, and some characteristic of a species 
or area may contribute to all three. For example, distribution across a 
wide variety of habitat types is an indicator of representation, but it 
may also indicate a broad geographic distribution contributing to 
redundancy (decreasing the chance that any one event affects the entire 
species), and the likelihood that some habitat types are less 
susceptible to certain threats, contributing to resiliency (the ability 
of the species to recover from disturbance). None of these concepts is 
intended to be mutually exclusive, and a portion of a species' range 
may be determined to be ``significant'' due to its contributions under 
any one or more of these concepts.
    For the purposes of this finding, we determine if a portion's 
biological contribution is so important that the portion qualifies as 
``significant'' by asking whether, without that portion, the 
representation, redundancy, or resiliency of the species would be so 
impaired that the species would have an increased vulnerability to 
threats to the point that the overall species would be in danger of 
extinction (i.e., would be ``endangered''). Conversely, we would not 
consider the portion of the range at issue to be ``significant'' if 
there is sufficient resiliency, redundancy, and representation 
elsewhere in the species' range that the species would not be in danger 
of extinction throughout its range if the population in that portion of 
the range in question became extirpated (extinct locally).
    We recognize that this definition of ``significant'' (a portion of 
the range of a species is ``significant'' if its contribution to the 
viability of the species is so important that, without that portion, 
the species would be in danger of extinction) establishes a threshold 
that is relatively high. On the one hand, given that the consequences 
of finding a species to be endangered or threatened in an SPR would be 
listing the species throughout its entire range, it is important to use 
a threshold for ``significant'' that is robust. It would not be 
meaningful or appropriate to establish a very low threshold whereby a 
portion of the range can be considered ``significant'' even if only a 
negligible increase in extinction risk would result from its loss. 
Because nearly any portion of a species' range can be said to 
contribute some increment to a species' viability, use of such a low 
threshold would require us to impose restrictions and expend 
conservation resources disproportionately to conservation benefit: 
Listing would be rangewide, even if only a portion of the range of 
minor conservation importance to the species is imperiled. On the other 
hand, it would be inappropriate to establish a threshold for 
``significant'' that is too high. This would be the case if the 
standard were, for example, that a portion of the range can be 
considered ``significant'' only if threats in that portion result in 
the entire species' being currently endangered or threatened. Such a 
high bar would not give the SPR phrase independent meaning, as the 
Ninth Circuit held in Defenders of Wildlife v. Norton, 258 F.3d 1136 
(9th Cir. 2001).
    The definition of ``significant'' used in this finding carefully 
balances these concerns. By setting a relatively high threshold, we 
minimize the degree to which restrictions will be imposed or resources 
expended that do not contribute substantially to species conservation. 
But we have not set the threshold so high that the phrase ``in a 
significant portion of its range'' loses independent meaning. 
Specifically, we have not set the threshold as high as it was under the 
interpretation presented by the Service in the Defenders litigation. 
Under that interpretation, the portion of the range would have to be so 
important that current imperilment there would mean that the species 
would be currently imperiled everywhere. Under the definition of 
``significant'' used in this finding, the portion of the range need not 
rise to such an exceptionally high level of

[[Page 54329]]

biological significance. (We recognize that if the species is imperiled 
in a portion that rises to that level of biological significance, then 
we should conclude that the species is in fact imperiled throughout all 
of its range, and that we would not need to rely on the SPR language 
for such a listing.) Rather, under this interpretation, we ask whether 
the species would be endangered everywhere without that portion (i.e., 
if that portion were completely extirpated). In other words, the 
portion of the range need not be so important that even the species 
being in danger of extinction in that portion would be sufficient to 
cause the species in the remainder of the range to be endangered; 
rather, the complete extirpation (in a hypothetical future) of the 
species in that portion would be required to cause the species in the 
remainder of the range to be endangered.
    The range of a species can theoretically be divided into portions 
in an infinite number of ways. However, there is no purpose to 
analyzing portions of the range that have no reasonable potential to be 
significant or to analyzing portions of the range in which there is no 
reasonable potential for the species to be endangered or threatened. To 
identify only those portions that warrant further consideration, we 
determine whether there is substantial information indicating that: (1) 
The portions may be ``significant,'' and (2) the species may be in 
danger of extinction there or likely to become so within the 
foreseeable future. Depending on the biology of the species, its range, 
and the threats it faces, it might be more efficient for us to address 
the significance question first or the status question first. Thus, if 
we determine that a portion of the range is not ``significant,'' we do 
not need to determine whether the species is endangered or threatened 
there; if we determine that the species is not endangered or threatened 
in a portion of its range, we do not need to determine if that portion 
is ``significant.'' In practice, a key part of the determination that a 
species is in danger of extinction in a significant portion of its 
range is whether the threats are geographically concentrated in some 
way. If the threats to the species are essentially uniform throughout 
its range, no portion is likely to warrant further consideration. 
Moreover, if any concentration of threats to the species occurs only in 
portions of the species' range that clearly would not meet the 
biologically based definition of ``significant,'' such portions will 
not warrant further consideration.
    We evaluated the current range of the bleached sandhill skipper to 
determine if there is any apparent geographic concentration of the 
primary stressors potentially affecting the subspecies including water 
development, livestock grazing, energy development, climate change, and 
limited range and small population size. On the basis of our review, we 
found no geographic concentration of threats either on public or 
private lands to suggest that the bleached sandhill skipper may be in 
danger of extinction in that portion of its range. We found no area 
within the range of the bleached sandhill skipper where the potential 
threats are significantly concentrated or substantially greater than in 
other portions of its range. We also found that lost historical range 
does not constitute a significant portion of the range for the bleached 
sandhill skipper because there is no information indicating that there 
has been a range contraction for this subspecies. Therefore, we find 
factors affecting the subspecies are essentially uniform throughout its 
range, indicating no portion of the skipper's range warrants further 
consideration of possible status as an endangered or threatened species 
under the Act.
    We found no information to indicate that the bleached sandhill 
skipper is in danger of extinction now, nor is it likely to become 
endangered within the foreseeable future, throughout all or a 
significant portion of its range. Therefore, listing the bleached 
sandhill skipper as an endangered or threatened species under the Act 
is not warranted at this time.
    We request that you submit any new information concerning the 
status of, or threats to, the bleached sandhill skipper to our Nevada 
Fish and Wildlife Office (see ADDRESSES section) whenever it becomes 
available. New information will help us monitor the bleached sandhill 
skipper and encourage its conservation. If an emergency situation 
develops for the bleached sandhill skipper or any other species, we 
will act to provide immediate protection.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the Nevada Fish and 
Wildlife Office (see FOR FURTHER INFORMATION CONTACT).

Authors

    The primary authors of this notice are the staff members of the 
Nevada Fish and Wildlife Office (see FOR FURTHER INFORMATION CONTACT).

Authority

    The authority for this action is the Endangered Species Act of 
1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: August 20, 2012.
Benjamin N. Tuggle,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2012-21243 Filed 8-31-12; 8:45 am]
BILLING CODE 4310-55-P