Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24253 

standard, and prohibit wideband 

operations on a going forward basis. The 

public safety community expressed 

broad support for a broadband 

allocation to enable advanced 

communications capabilities. The 

availability of a contiguous block of 

broadband spectrum, subject to a 

nationwide interoperability standard, 

would enable partnerships with 

commercial licensees in adjacent 

broadband spectrum. As a result, the 

proposed band plan would ultimately 

enable public safety entities to utilize 

the 700 MHz spectrum in a more costeffective and spectrally efficient manner 

to address their homeland security and 

emergency response roles. Because the 

Commission does not anticipate that the 

proposal will impose additional 

economic burdens on public safety, and 

is in fact designed to reduce economic 

burdens on public safety, the 

Commission has taken steps to 

minimize any adverse impact of the rule 

changes. 

114. The FNPRM also seeks comment 

on its tentative conclusion to 

consolidate the narrowband spectrum to 

the top of the public safety band and 

locate the broadband spectrum at the 

bottom of the public safety band, in 

light of the potentially significant 

benefits such reconfiguration would 

afford the public safety community. The 

alternative would be to retain the 

existing band plan. The FNPRM seeks 

comment on how to implement 

reconfiguration of the narrowband 

channels with minimum disruption to 

incumbent operations. The FNPRM 

invites comment on an appropriate 

transition mechanism, including how to 

accommodate public safety operations 

in the border areas with Canada and 

Mexico, and the costs of relocation and 

how such costs will be covered. The 

Commission expects that the number of 

entities impacted and expected cost of 

reconfiguration should be relatively 

minor. To assist the Commission in its 

analysis, however, commenters are 

requested to provide information 

regarding the number of narrowband 

radios that are deployed, as well as the 

number of radios that are in active use, 

and thus would be affected by the 

proposed changes to the 700 MHz 

public safety band plan as described in 

the FNPRM. The FNPRM recognizes 

that the public safety community’s 

ability to fund the reconfiguration may 

be limited. Thus, in addition to 

considering whether public safety 

should pay for its own relocation costs, 

the FNPRM seeks comment on several 

alternatives, including whether to 

impose funding requirements on 700 

MHz commercial licensees, and whether 

Federal or other grant monies could be 

used. In the event the Commission 

determines to license the broadband 

allocation to a nationwide public safety 

broadband licensee, the FNPRM also 

invites comment on whether that 

licensee should be assigned 

responsibility for funding the 

reconfiguration. 

115. Although the economic burden 

on public safety to effectuate 

reconfiguration is expected to be 

relatively small, the FNPRM will 

develop a record on the true costs that 

would be implicated. The Commission 

remains open to considering 

alternatives, however, should an 

alternative be stated in comments that 

would reach our objectives and 

minimize the impact on public safety 

entities. 

116. Frontline Proposal. In the 

FNPRM, the Commission seeks 

comment on Frontline’s proposed 

‘‘Public Safety Broadband Deployment 

Plan.’’ Although Frontline proposes that 

the Commission offer bidding credits to 

applicants based on their status as a 

small business, the Commission 

tentatively concludes in the FNPRM 

that it should not offer any bidding 

preferences, such as bidding credits, to 

applicants for the ‘‘E Block’’ license. 

The FNPRM states, however, that the 

public interest would not appear to 

favor giving applicants a preference 

when bidding for the ‘‘E Block’’ license 

based on their limited financial 

resources, as the Commission does 

when it offers bidding credits to small 

businesses in these circumstances. The 

Commission stated that its concerns 

regarding the capital needed to 

implement a nationwide service are 

especially acute in this instance, 

because the ‘‘E Block’’ licensee would 

be responsible for constructing a 

network to meet the needs of critical 

public safety providers. The 

Commission seeks comment on this 

tentative conclusion. 

F. Federal Rules That May Duplicate, 

Overlap, or Conflict With the Proposed 

Rules 

117. None. 

Ordering Clauses 

118. It is further ordered pursuant to 

Sections 1, 2, 4(i), 5(c), 7, 10, 201, 202, 

208, 214, 301, 302, 303, 307, 308, 309, 

310, 311, 314, 316, 319, 324, 332, 333, 

336, 337, 614, 615, and 710 of the 

Communications Act of 1934, as 

amended, 47 U.S.C. 151, 152, 154(i), 

155(c), 157, 160, 201, 202, 208, 214, 301, 

302, 303, 307, 308, 309, 310, 311, 314, 

316, 319, 324, 332, 333, 336, and 337, 

that this further notice of proposed 

rulemaking in WT Docket No. 06–150, 

CC Docket No. 94–102, WT Docket No. 

01–309, WT Docket No. 03–264, WT 

Docket No. 06–169, WT Docket No. 96– 

86 and PS Docket No. 06–229 IS 

ADOPTED. 

119. It is further ordered that pursuant 

to applicable procedures set forth in § §

1.415 and 1.419 of the Commission’s 

Rules, 47 CFR 1.415, 1.419, interested 

parties may file comments on the 

further notice of proposed rulemaking 

on or before May 23, 2007 and reply 

comments on or before May 30, 2007. 

120. It is further ordered that the 

Commission’s Consumer and 

Governmental Affairs Bureau, Reference 

Information Center, SHALL SEND a 

copy of this further notice of proposed 

rulemaking, including the Initial 

Regulatory Flexibility Analysis, to the 

Chief Counsel for Advocacy of the Small 

Business Administration. 

121. It is further ordered that the 

Commission shall send a copy of this 

further notice of proposed rulemaking 

in a report to be sent to Congress and 

the General Accounting Office pursuant 

to the Congressional Review Act, 5 

U.S.C. 801(a)(1)(A). 

Federal Communications Commission. 

Marlene H. Dortch, 

Secretary. 

[FR Doc. E7–8440 Filed 5–1–07; 8:45 am] 

BILLING CODE 6712–01–P 

DEPARTMENT OF THE INTERIOR 

Fish and Wildlife Service 

50 CFR Part 17 

Endangered and Threatened Wildlife 

and Plants; 12-Month Finding on a 

Petition to List the Sand Mountain Blue 

Butterfly (Euphilotes pallescens ssp. 

arenamontana) as Threatened or 

Endangered with Critical Habitat 

AGENCY: Fish and Wildlife Service, 

Interior. 

ACTION: Notice of 12-month petition 

finding. 

SUMMARY: We, the U.S. Fish and 

Wildlife Service (Service), announce our 

12-month finding on a petition to list 

the Sand Mountain blue butterfly 

(Euphilotes pallescens arenamontana) 

as threatened or endangered under the 

Endangered Species Act of 1973, as 

amended (Act). After a thorough review 

of all available scientific and 

commercial information, we find that 

the petitioned action is not warranted. 

We ask the public to continue to submit 

to us any new information concerning 

mmaher on DSK3CLS3C1PROD with $$_JOB

24254 Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 

the status of, and threats to, this 

subspecies. This information will help 

us to monitor and encourage the 

ongoing management of this subspecies. 

DATES: The finding announced in this 

document was made May 2, 2007. 

ADDRESSES: Data, information, 

comments, or questions regarding this 

notice should be submitted to the Field 

Supervisor, Nevada Fish and Wildlife 

Office, U.S. Fish and Wildlife Service, 

1340 Financial Boulevard, Suite 234, 

Reno, NV 89502. The complete 

administrative file for this finding is 

available for inspection, by appointment 

and during normal business hours, at 

the above address. 

FOR FURTHER INFORMATION CONTACT: 

Robert D. Williams, Field Supervisor, 

Nevada Fish and Wildlife Office (see 

ADDRESSES) (telephone 775/861–6300; 

facsimile 775/861–6301). 

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 List of 

Endangered and Threatened Wildlife 

and Plants that contains substantial 

scientific and commercial information 

that listing may be warranted, we make 

a finding within 12 months of the date 

of our receipt of the petition on whether 

the petitioned action is: (a) Not 

warranted, (b) warranted, or (c) 

warranted, but the immediate proposal 

of a regulation implementing the 

petitioned action is precluded by other 

pending proposals to determine whether 

any species is threatened or endangered, 

and expeditious progress is being made 

to add or remove qualified species from 

the List of Endangered and Threatened 

Wildlife and Plants. Such 12-month 

findings are to be published promptly in 

the Federal Register. Section 4(b)(3)(C) 

of the Act requires that a petition for 

which the requested action is found to 

be warranted but precluded shall be 

treated as though resubmitted on the 

date of such finding (that is, requiring 

a subsequent finding to be made within 

12 months). 

Previous Federal Action 

We included the Sand Mountain blue 

butterfly under the name Euphilotes rita 

ssp. as a Category 2 candidate species in 

our November 21, 1991 Candidate 

Notice of Review (CNOR) (56 FR 58829). 

Category 2 included taxa for which 

information in our possession indicated 

that a proposed listing rule was possibly 

appropriate, but for which sufficient 

data on biological vulnerability and 

threats were not available to support a 

proposed rule. The Sand Mountain blue 

butterfly remained a Category 2 

candidate as Euphilotes rita ssp. in our 

1994 CNOR (November 15, 1994; 59 FR 

59020). In the CNOR published on 

February 28, 1996 (61 FR 7596), 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 

matching this definition were known as 

Category 1 candidates for listing. Thus 

the Service no longer considered 

Category 2 species as candidates, and 

did not include them in the 1996 or any 

subsequent CNORs. The decision to stop 

considering 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. Since the Sand Mountain blue 

butterfly was a Category 2 species, we 

no longer recognized it as a candidate 

species as of the February 28, 1996, 

CNOR (61 FR 7457). 

On April 23, 2004, we received a 

formal petition, dated April 23, 2004, 

from the Center for Biological Diversity, 

Xerces Society, Public Employees for 

Environmental Responsibility, and the 

Nevada Outdoor Recreation Association, 

requesting that the Sand Mountain blue 

butterfly, currently recognized as 

Euphilotes pallescens ssp. 

arenamontana taxonomically, known 

only from Sand Mountain, Nevada, be 

listed as threatened or endangered in 

accordance with section 4 of the Act, 

and that critical habitat be designated 

for the species concurrent with the 

listing. The petition is available on the 

Nevada Fish and Wildlife Office Web 

site (go to http://www.fws.gov/nevada/ 

and click on the Nevada Species link, 

then on Sand Mountain blue butterfly 

link). 

Action on this petition was precluded 

by court orders and settlement 

agreements for other listing actions that 

required nearly all of our listing funds 

for fiscal years 2004 and 2005. On 

September 26, 2005, we received a 60- 

day notice of intent to sue, and on 

January 5, 2006, we received a 

complaint regarding our failure to carry 

out the 90-day finding on the petition to 

list the Sand Mountain blue butterfly. 

On April 20, 2006, we reached an 

agreement with the plaintiffs to submit 

to the Federal Register a completed 90- 

day finding by July 28, 2006. The 

agreement specified that if our 90-day 

finding concluded that the petition 

contained substantial information, we 

would complete a 12-month finding by 

April 26, 2007 (Center for Biological 

Diversity et al. v. Norton, and U.S. Fish 

and Wildlife Service (CV–00023–LKK– 

GGH), (E.D. Cal)). 

On August 8, 2006, we published our 

90-day finding in the Federal Register 

(71 FR 44988), in which we concluded 

that the petition presented substantial 

scientific or commercial information to 

indicate that listing the Sand Mountain 

blue butterfly may be warranted, we 

initiated a status review of the taxon, 

and we solicited comments and 

information to be provided in 

connection with the status review by 

October 10, 2006. This notice 

constitutes our 12-month finding and is 

submitted in fulfillment of the April 20, 

2006, stipulated settlement agreement. 

On August 18, 2006, we became a 

signatory to the multi-party Sand 

Mountain Blue Butterfly Conservation 

Plan (Conservation Plan), which became 

effective September 21, 2006 (Lahontan 

Valley Environmental Alliance (LVEA), 

2006). For a further discussion of the 

Conservation Plan, see the 

‘‘Conservation Efforts’’ section below. 

Biology and Distribution 

The genus Euphilotes, in the family 

Lycaenidae, is comprised of five species 

of small, pale blue butterflies from 

western North America that are 

distinguished by discrete differences in 

genitalia (Pratt 1994, p. 388). The genus 

is noteworthy for its close relationship 

with the plant genus Eriogonum (wild 

buckwheat), a genus of about 250 

species of shrubs, subshrubs, and herbs 

largely from western North America 

(Reveal 2005). Euphilotes taxa are 

among the most specialized of the North 

American butterflies in host plant 

adaptations (Pratt 1988, p. 63). They 

typically utilize species of Eriogonum 

for mating, obtaining nectar, host 

searching, and egg laying (Pratt 1994, p. 

388). Many of the species and 

subspecies within the genus have highly 

restricted ranges, in part because of this 

specialized relationship with 

Eriogonum. The larvae (and to some 

degree the adults) of Euphilotes 

subspecies are known to specialize on 

the flowers and seeds of specific 

Eriogonum (Pratt 1988, p. 104). This 

relationship has been the subject of 

several studies on evolution (Shields 

and Reveal 1988, pp. 51–93; Pratt 1988, 

pp. 1–653; Pratt 1994, pp. 387–416). 

The pale blue butterfly, Euphilotes 

pallescens, was first described by Tilden 

and Downey in 1955 under the name 

Philotes pallescens based on specimens 

collected in Tooele County, Utah (Pratt 

1988, p. 18; Mattoni 1965, pp. 81, 94). 

Mattoni (1965, p. 94) reduced the taxon 

to a subspecies which he called Philotes 

mmaher on DSK3CLS3C1PROD with $$_JOB

Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24255 

(=Euphilotes) rita ssp. pallescens, but he 

only examined a pair of specimens 

collected at the same time as the 

original collection by Tilden and 

Downey. Mattoni based his taxonomic 

conclusion on the configuration of the 

male genitalia, which was thought to be 

the primary characteristic 

distinguishing P. rita from all other 

members of the genus (Mattoni 1965, p. 

81; Shields 1977, p. 2), and his opinion 

that ‘‘greater biological meaning arises 

from a classification based upon 

relationship rather than difference’’ 

(Mattoni 1965, p. 99). 

In the first modern biosystematic 

analysis of the genus, Pratt (1988, 1994) 

used cladistic analysis, a method of 

examining taxonomic relationships 

among species using shared derived 

characteristics (features possessed by 

two or more taxa in common), to assess 

its members of the genus Euphilotes. He 

compared 79 morphological characters 

and analyzed enzymes (proteins), allelic 

variation (variation in genes coding for 

same trait), and diapause (period of 

suspended growth or development 

similar to hibernation) intensity among 

36 taxa of Euphilotes from western 

North America (Pratt 1988, 1994). Based 

on these analyses, he concluded that 

Euphilotes pallescens should be 

recognized as a full species (Pratt 1994, 

pp. 401–402; Pratt and Emmel 1998, p. 

209). The Sand Mountain blue butterfly 

was first described as Euphilotes 

pallescens ssp. arenamontana by Austin 

in 1998 (1998, pp. 556–557); it is one of 

seven named subspecies of the pallid 

blue butterfly in Nevada (Murphy et al. 

2006, p. 2). Prior to the 1998 publication 

of this name, the Sand Mountain blue 

butterfly had been considered a 

potentially distinct subspecies of 

Euphilotes rita (Austin 1985, p. 105), 

the name under which it was previously 

assigned a Federal Category 2 candidate 

status (see Previous Federal Action 

section). 

The Sand Mountain blue butterfly is 

small with pale blue coloration. Males 

have a wingspan that ranges from 10.0 

to 11.8 millimeters (mm) (0.39 to 0.46 

inches (in)), with an average of 11.1 mm 

(0.44 in). The dorsum (back) is pale 

bluish violet, often whitish distally, 

with a narrow (0.5 mm (0.002 in)) black 

outer margin. There is usually a series 

of dots on the hindwing, but sometimes 

no more than a terminal line on the 

forewing. There is generally an 

indistinct pinkish to pale orange aurora 

of moderate width on the posterior 

hindwing. At the vein tips on the 

posterior of both wings, there are fringes 

of white with indistinct gray checkering. 

The bottom surface of the male 

abdomen is chalky white. Macules 

(patches of different coloration) are 

small, often nearly obsolete on the 

hindwing. Females have a wingspan 

that ranges from 10.0 to 11.9 mm (0.39 

to 0.46 in), with an average of 10.9 mm 

(0.43 in). The female dorsum (back) is 

brown to tan, and usually pale bluishgray basally on both wings. The 

forewing has a faint brown cell-end bar, 

while the hindwing has marginal dots. 

The forewing apex is usually whitish. 

The hindwing aurora is pale orange to 

pale pink, usually grading to nearly 

white distally and not strongly 

contrasting (Austin 1998, p. 556). 

The Sand Mountain blue butterfly is 

the palest of all Euphilotes. The ground 

color of both sexes is considerably paler 

than that of E. pallescens ssp. 

pallescens. The pinkish aurora is unlike 

that of any other Euphilotes. The pale 

bluish-gray wing bases of the female do 

not contrast with the distal area of the 

wing as they do on E. pallescens ssp. 

pallescens. The black macules of E. 

pallescens ssp. arenamontana tend to be 

smaller than those of E. pallescens ssp. 

pallescens (Austin 1998, p. 557). 

The species Euphilotes pallescens is 

distributed discontinuously from 

southern and central California (east of 

the Sierra Nevada) through the Great 

Basin of central Nevada and across 

central and southern Utah (Pratt 1994, 

p. 402; Shields 1977). The subspecies 

known as the Sand Mountain blue 

butterfly is known only from Sand 

Mountain, Churchill County, Nevada, 

where it is dependent on its host plant, 

Eriogonum nummulare (Kearney 

buckwheat) (Austin 1998, p. 557; 

Shields 1977, p. 3), a long-lived, 

perennial shrub with numerous 

branches (Reveal 2002, p. 1), that occurs 

in scattered sandy locations in several 

western States (Welsh et al. 1993, p. 

547). Searches have been conducted 

within 60 miles (mi) (100 kilometers 

(km)) of Sand Mountain in an effort to 

determine the presence or absence of 

Kearney buckwheat occurrences on 

sand dunes that might be able to sustain 

occurrences of Sand Mountain blue 

butterflies; to date, no additional 

populations of Kearney buckwheat have 

been found (Funari 2004; Caicco 2006a, 

2006b). Kearney buckwheat was 

reported in 1981 to occur in small 

numbers along the eastern edge of 

Blowsand Mountain, which lies about 

12 mi (19.2 km) southwest of Sand 

Mountain (The Nature Conservancy 

2004), but no plants were observed 

during three reconnaissance surveys in 

2003 and 2004 (Funari 2004). Many 

butterflies in the family Lycaenidae 

have very limited dispersal distances 

that revolve intimately around their 

patchily distributed host plants 

(Peterson 1996, p. 1990). Dispersal of 

the Sand Mountain blue butterfly has 

not been studied, but in another species 

in the same genus, Euphilotes enoptes, 

most adults were found to move less 

than 1,640 feet (ft) (500 meters (m)) and 

their dispersal distance rarely exceeded 

0.6 mi (1 km) (Arnold 1983 and 

Peterson 1994, as cited in Peterson 

1996, p. 1990). 

Isolated sand dunes are common 

throughout the Great Basin, often 

associated with depositional areas for 

windborne sediments derived from the 

now dry beds of Pleistocene Epoch 

lakes; these geologic features are 

referred to as pluvial lakes, indicating 

their origins during the periods of 

greater precipitation and lower 

evaporation typical of the Pleistocene 

climate of the Great Basin. Studies of 

dispersal of the sand dune-obligate 

beetle, Eusattus muricatus, widely 

distributed throughout the Great Basin 

and Mojave Deserts, have shown that 

populations on dunes separated by 

approximately 60 mi (100 km) generally 

exchange very few migrants, even 

among dunes within the same pluvial 

basin (Britten and Rust 1996, p. 651). 

Based on these data, the authors of this 

study recommended that all duneobligate populations in the Great Basin 

separated by 60 mi (100 km) or more 

from the nearest dune within the same 

pluvial lake basin be considered 

genetically isolated (Britten and Rust 

1996, p. 651). In fact, taxonomic 

distinctions made within Euphilotes 

pallescens are generally consistent with 

this approach, with E. p. ssp. calneva 

described from sand dunes in the Honey 

Lake area of northeastern California and 

near Sand Pass, in adjacent Nevada 

(Emmel and Emmel, pp. 277–282; 

Brussard 2006, p. 1; Murphy 2006a), 

and E. p. ssp. ricei, known only from the 

Silver State Sand Dunes, which are 

north of Winnemucca, Nevada (Austin 

et al. 2000, p. 3; Brussard 2006, p. 1; 

Murphy 2006a); each of these sand dune 

areas lies within the Lahontan pluvial 

basin at a minimum distance of about 

120 mi (192 km) from Sand Mountain. 

We conclude that it is highly unlikely 

that the Sand Mountain blue butterfly 

occurs at other sites within 60 mi (100 

km). Areas within 60 mi (100 km) have 

been surveyed to various extents with 

no reported observations of the 

butterfly’s host plant, Kearney 

buckwheat. We also conclude that the 

subspecies is unlikely to be found at 

sites located more than 60 mi (100 km) 

from Sand Mountain. Any population of 

Euphilotes pallescens found at any sites 

at distances greater than 60 mi (100 km) 

is most likely to be another subspecies 

of Euphilotes pallescens, based on the 

mmaher on DSK3CLS3C1PROD with $$_JOB

24256 Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 

current accepted taxonomy of the 

species and the likely genetic isolation 

of E. pallescens ssp. arenamontana due 

to its life history, ecology, and limited 

dispersal ability. Based on satellite 

imagery used to identify dune shrub 

habitat (BLM 2003, 2004), we estimate 

that the current range of the subspecies 

is approximately 1000 acres (405 ha), 

within which Kearney buckwheat is 

scattered in patches and is a dominant 

or co-dominant shrub on approximately 

500–600 ac (202–243 ha) (BLM 2006b). 

Thus, while Sand Mountain blue 

butterflies may be present anywhere 

within their entire 1,000 ac (405 ha) 

range, only 50 to 60 percent of this 

range is thought to have the Kearney 

buckwheat shrubs on which they 

depend. 

All Euphilotes larvae are believed to 

diapause by burying into the soil 12.7 to 

38.1 inches (in) (5 to 15 centimeters 

(cm)) prior to pupation, which may be 

delayed for up to 6 years depending on 

climatic conditions (Pratt 1988, p. 319). 

When this period of diapause is broken, 

the pupae begin development and 

eventually emerge as adults from 

beneath the soil. The ability of larvae to 

suspend growth for varying periods of 

time may be part of the reason that the 

genus Euphilotes has high genetic 

diversity (Pratt 1988, pp. 427–428), 

presumably because it increases the 

likelihood for random mating. 

Because of the small size of the Sand 

Mountain blue butterfly and the 

frequent high winds typical of the Sand 

Mountain area, it is likely that adult 

butterflies spend most of their life 

sheltered within the canopy of Kearney 

buckwheat plants (Murphy 2006a). 

Males of the genus exhibit a type of 

mate-searching behavior known as 

patrolling, which involves active 

searching for potential mates (Pratt 

1988, p. 371). 

Kearney buckwheat typically occurs 

at Sand Mountain as a dominant or codominant with other shrubs on less 

active, smaller vegetated dunes around 

the periphery of the main dune (The 

Nature Conservancy 2004, pp. 24–26). 

Kearney buckwheat flowers and seeds 

are the sole food source for the larvae 

(Pratt 1988, p. 64) and an important 

nectar source for adults during their 

flight period (Murphy et al. 2006, p. 1). 

The flowering period of the Kearney 

buckwheat at Sand Mountain begins in 

late June to early July and continues 

through September (Reveal 2002, p. 2). 

Like many species of wild buckwheat 

(Meyer 2006), individual Kearney 

buckwheat plants may be in continuous 

flower for well over a month (Caicco 

2006c). Individual flowers within a 

cluster bloom in succession so that after 

the initial bloom, both seeds and 

flowers are present for extended periods 

(Caicco 2006c). 

The Sand Mountain blue butterfly has 

one brood from mid July to midSeptember (Austin 1998, p. 557; Shields 

1977, p. 5), a period that coincides with 

the flowering/fruiting period of Kearney 

buckwheat. During the summer of 2006, 

scientists from the University of Nevada 

initiated a research effort to determine 

the distributional relationship between 

the butterfly, its host plant, and the 

dune shrub community. Sand Mountain 

blue butterflies were counted along a 

17,061 ft (5,200 m) transect, with five 

surveys made between July 15 and 

August 9, 2006 (Murphy et al. 2006, p. 

4). The number of Sand Mountain blue 

butterflies counted along the transects 

increased over the duration of the 

sampling period; because no decline 

was detected in the number of 

butterflies counted over that time 

period, researchers were unable to 

determine the precise length of the 2006 

flight season (Murphy et al. 2006, p. 5 

and Figure 2). 

The researchers found that butterflies 

occurred across the entire extent of their 

study area, although, regardless of the 

sampling date, butterflies were always 

more abundant in the northeastern 

portions of the study than in the 

southwestern areas (Murphy et al. 2006, 

Figure 2). The researchers reported that 

‘‘as the season matured, multiple [Sand 

Mountain blue] butterflies were 

observed flying around nearly every 

buckwheat plant at nearly every site on 

nearly every site visit. Even individual 

buckwheat shrubs, which were isolated 

from others by as many as hundreds of 

meters due to devegetation from vehicle 

activities, were visited by [Sand 

Mountain] blue butterflies’’ (Murphy et 

al. 2006, pp. 5–6). 

The abundance of the butterfly was 

closely correlated with Kearney 

buckwheat flower phenology and 

abundance. Early in the flight season, 

many flowers were unopened; flowers 

sequentially opened as the sampling 

period progressed toward August, 

although some unopened buds 

remained after sampling was terminated 

(Murphy et al. 2006, p. 6). Butterfly 

abundance was strongly correlated with 

both the number of buckwheat 

inflorescences (flowers) and the 

abundance of the Kearney buckwheat 

itself (Murphy et al. 2006, p. 6 and 

Figure 6). 

The researchers also found that the 

abundance of Kearney buckwheat varies 

considerably throughout the dune shrub 

habitat, with higher host plant and 

butterfly densities in some areas. At a 

number of their sample locations, 

Kearney buckwheat was the most 

abundant shrub in the dune shrub 

community (Murphy et al. 2006, p. 6 

and Figure 5). The buckwheat was 

usually among the dominant shrub 

species both along the transect itself and 

within individual plots (Murphy et al. 

2006, p. 6 and Figure 6). 

The scientists made three conclusions 

from the data they collected during the 

2006 flight season of the Sand Mountain 

blue butterfly. First, there was a large 

number of Sand Mountain blue 

butterflies—‘‘perhaps hundreds of 

thousands’’—a number ‘‘substantially 

above a level that would indicate a need 

to carry out in situ or other actions to 

enhance population size above a critical 

minimum’’ (Murphy et al. 2006, p. 7). 

Second, the butterfly appears to cooccur with its host plant across the 

entirety of the shrub’s range at Sand 

Mountain, and the habitat quality for 

the butterfly increases in parallel with 

the shrub density from southwest to 

northeast across the site (Murphy et al. 

2006, pp. 7–8). Third, the Kearney 

buckwheat occurs in a dune shrub 

community with abundant Atriplex 

canescens (four-wing saltbush) at lower 

elevations that transitions into a 

community with a more diverse 

assemblage of shrub species at higher 

elevations (Murphy et al. 2006, Figure 

5). Along this gradient, the abundance 

of the Kearney buckwheat and, 

therefore, the density of butterflies 

varied in parallel (Murphy et al. 2006, 

p. 8). 

Conservation Efforts 

On August 18, 2004, the Lahontan 

Valley Environmental Alliance (LVEA), 

at the request of its board of directors, 

initiated a public planning effort to 

develop a conservation plan for the 

Sand Mountain blue butterfly. The 

LVEA was created in 1993 by an 

agreement among local governments 

and agencies to educate the public and 

coordinate efforts to protect the natural 

resources and agricultural-based 

economy of the communities in 

Churchill County. Over the past 13 

years, the LVEA has worked with 

various interests to build knowledge 

and to improve communications among 

the communities, stakeholder groups, 

local governments, and State and 

Federal agencies involved in, or affected 

by, the natural resources issues of the 

region (LVEA 2006, p. 1). 

Through the public planning effort 

described above, the LVEA organized 

and facilitated a working group to 

identify and address the needs of the 

Sand Mountain blue butterfly. This 

working group met regularly over the 

subsequent 21 months. In accordance 

mmaher on DSK3CLS3C1PROD with $$_JOB

Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24257 

with the Nevada Open Meeting Law 

(Nevada Revised Statute, Chapter 241), 

all meetings were open to the public 

and noticed in advance with agendas 

posted in public facilities (Nevada Open 

Meeting Law Manual 2005). Meeting 

notes are posted on the LVEA Web site 

(go to http://www.lvea.org/workgrp.htm 

and click on the link for this species and 

then click on the link for meeting notes). 

Participants in the working group 

included representatives from the 

LVEA, the Bureau of Land Management 

(BLM), the Service, the City of Fallon, 

Churchill County, the Fallon Paiute 

Shoshone Tribe (Tribe), the Friends of 

Sand Mountain (FOSM), the California 

Off-Road Vehicle Association (CORVA), 

the United States Naval Air Station 

Fallon, and private citizens (LVEA 2006, 

pp. 1–2). 

The purpose of this effort was to 

develop a Conservation Plan to provide 

long term protection for the Sand 

Mountain blue butterfly and its habitat, 

particularly, its host plant, Kearney 

buckwheat (Eriogonum nummulare). 

Final agreement on the Conservation 

Plan was reached on May 3, 2006, and 

it was signed by representatives of the 

BLM, the Service, the Tribe, CORVA, 

FOSM, and Churchill County in August 

and September, 2006. The Conservation 

Plan identifies specific actions that are 

necessary to: (1) Eliminate or reduce 

known threats, (2) incorporate species 

conservation measures into planning 

and management activities, (3) educate 

permittees and recreation users, and (4) 

monitor species status trends and 

habitat quality and requirements. 

A designated route system, a 

conservation action identified in the 

Conservation Plan (LVEA 2006, pp. 14– 

19), has been implemented by the BLM 

at Sand Mountain to protect the habitat 

of the Sand Mountain blue butterfly 

from further damage and destruction by 

off-road vehicles (72 FR 12187, March 

15, 2007). We used criteria specified in 

our Policy for Evaluation of 

Conservation Efforts When Making 

Listing Decisions (PECE) (68 FR 15100– 

15115, March 28, 2003) to evaluate the 

certainty of effectiveness of this 

designated route system and determined 

there is a high level of certainty of 

effectiveness of the designated route 

system; consequently, we can consider 

this action in making a determination as 

to whether the Sand Mountain blue 

butterfly meets the Service’s definition 

of a threatened or endangered species 

(Service 2007). 

Summary of Factors Affecting the 

Species 

Section 4 of the Act (16 U.S.C. 1533) 

and implementing regulations at 50 CFR 

Part 424 set forth procedures for adding 

species to the Federal List of 

Endangered and Threatened Wildlife. In 

making this finding, we summarize 

below information regarding the status 

of this species in relation to the five 

factors provided in section 4(a)(1) of the 

Act. In making our 12-month finding, 

we have considered and evaluated all 

scientific and commercial information 

in our files, including relevant 

information received during the 

comment period that ended October 10, 

2006 (71 FR 44988). 

Factor A: The Present or Threatened 

Destruction, Modification, or 

Curtailment of the Species’ Habitat or 

Range 

The Sand Mountain blue butterfly is 

known only from Sand Mountain in 

Churchill County, Nevada, where it is 

dependent on its larval host plant, 

Kearney buckwheat (Austin 1998). The 

entire Sand Mountain dune system is 

estimated to extend over 2,581 ac (1,044 

ha), but Kearney buckwheat is not 

evenly distributed throughout this 

entire area; Kearney buckwheat plants 

are typically found on peripheral, more 

vegetated dunes, and are particularly 

common on the smaller dunes to the 

northeast of the main dune (BLM 2006a, 

Map 1). In most areas, Kearney 

buckwheat is a component of a diverse 

dune shrub habitat comprised of up to 

13 shrub species (BLM 2004). An 

estimated 1,000 ac (405 ha) of dune 

shrub habitat with varying amounts of 

Kearney buckwheat existed in 2003 

(BLM 2006b, p. 2). The current 

distribution of the shrubs, as described 

above, reflects both their natural 

adaptation to specific site conditions 

and the cumulative effect of 25 years of 

off-road vehicle use. 

A portion of the Sand Mountain dune 

system lies within the Sand Mountain 

Recreation Area (SMRA), a BLM 

designation that encompasses 4,795 ac 

(1,940 ha), and is about 1.0 mi (1.6 km) 

wide and 3.5 mi (5.6 km) long. The 

specific BLM designation of the SMRA 

for recreational use does not limit offroad or other forms of recreation only to 

this area. Furthermore, the BLM 

designation restricts non-recreation type 

activities, such as mineral mining, from 

occurring within the boundary of the 

designation. 

The recreational use designation for 

the SMRA was first established in 1968 

(BLM 1985, p. 4). By 1973, recreational 

use had reached 32,254 visitors 

annually (BLM 1985, p. 5). The first 

approved management plan for the area 

was developed more than a decade later 

(BLM 1985). Based on BLM information, 

we estimate that 40 percent, or 400 ac 

(162 ha) of the total of 1,000 ac (405 ha), 

of the Kearney buckwheat habitat occurs 

within the designated boundary of the 

SMRA (BLM 2006a, Map 1). The 

remaining estimated 60 percent of the 

Kearney buckwheat habitat occurs on 

BLM land outside of the eastern SMRA 

boundary. Until recently, off-road 

vehicle use was limited on only about 

40 ac (16 ha) of the SMRA; no Kearney 

buckwheat plants occur in this limiteduse area. The rest of the SMRA was 

open to unrestricted off-road vehicle 

use, as were all adjacent areas of the 

dune system. 

As early as 1985, motorized recreation 

by motorcycles, four-wheel drive 

vehicles, three wheelers, and dune 

buggies, accounted for over 90 percent 

of the total visits to the SMRA (BLM 

1985). Annual visitor use at the SMRA 

increased from about 16,000 persons in 

1981 to about 65,000 persons in 2005 

and was expected to increase again in 

2006 (BLM 2006c). Visitation tends to 

peak on holiday weekends; for example, 

more than 5,000 people were present 

over the Labor Day weekend in 2006 

(Nevada Appeal 2006, p. 1). In recent 

years, however, there has been a pattern 

of increased use on non-holiday 

weekends (BLM 2006c). 

The BLM’s Carson City Field Office 

has documented the expansion of an offroad vehicle route system based on an 

analysis of satellite imagery from 1978, 

1994, 1999, and 2002; the route system 

has grown from about 20 mi (32 km) of 

off-road vehicle trails in 1981 to about 

200 mi (320 km) in 2003 (BLM 2003). 

In addition to documenting the overall 

proliferation of off-road vehicle routes, 

the imagery clearly shows an increase in 

the amount of habitat fragmentation and 

an expansion of the off-road vehicle 

route system from the more accessible 

southern end of the main dune into 

dune shrub habitat adjacent to the 

SMRA toward the north and east that 

had been relatively undisturbed as 

recently as 1994 (BLM 2003). 

Based on the trail proliferation visible 

in the satellite imagery from 1978 to 

2003 (BLM 2003, 2004), we estimate 

that the shrub habitat on which the 

Sand Mountain blue butterfly depends 

may have been reduced by as much as 

50 percent over the past 25 years. At 

most, 1,000 ac (405 ha) of dune shrub 

habitat remains, and within that area 

500 ac (202 ha) to 600 ac (243 ha) may 

have Kearney buckwheat as a dominant 

or co-dominant shrub (BLM 2006c). We 

consider the entire 1,000 ac (405 ha) of 

dune shrub habitat to be the current 

range of the Sand Mountain blue 

butterfly; this includes non-Kearney 

buckwheat habitat through which the 

species passes, including areas devoid 

mmaher on DSK3CLS3C1PROD with $$_JOB

24258 Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 

of vegetation such as trails, as well as 

areas that support the Kearney 

buckwheat shrubs on which the 

butterfly depends for completion of its 

life cycle. Because the amount of 

Kearney buckwheat within a patch of 

dune shrub habitat varies, no precise 

data on the total number of individual 

Kearney buckwheat shrubs is available. 

We also have no reliable estimate of the 

historical distribution of the Kearney 

buckwheat at Sand Mountain other than 

an anecdotal report of a minor amount 

of vegetation having been lost along the 

periphery of the dune (Guiliani 1977); 

therefore, we consider the existing 

estimate of 1,000 ac (405 ha) of dune 

shrub habitat to approximate the 

historic range of the Sand Mountain 

blue butterfly. 

The Sand Mountain dune system was 

included in an initial conservation 

assessment of blowing sand mountains 

prepared by The Nature Conservancy 

(2004). This conservation assessment 

ranked the long-term (defined as greater 

than 100 years) viability of the Sand 

Mountain dune ecosystem based on 

size, condition, and landscape context, 

using information from the existing 

literature and expert opinion (The 

Nature Conservancy 2004, p. 29). Each 

of these factors had the potential to be 

ranked as very good, good, fair, or poor 

based on specific viability criteria (The 

Nature Conservancy 2004, p. 35). Size 

was ranked as good if there was 1,236 

ac-2,471 ac (500–1,000 ha) of connected 

habitat outside of the area heavily 

affected by off-road vehicle use (The 

Nature Conservancy 2004, p. 35). The 

condition rank was based on three 

criteria: (1) Whether invasive plants 

were present that could artificially 

stabilize dune dynamics; (2) whether 

other alterations affecting dune 

mobility, such as vegetation mortality or 

artificial mobilization of stable sands, 

were occurring; and (3), whether there 

was natural recruitment by key plant 

species. The condition was assigned a 

fair rank based on the fact that only the 

criterion regarding the presence of 

invasive plants was met (The Nature 

Conservancy 2004, p. 35). The 

landscape context was ranked very good 

based on the fact that the connection to 

the current sand source remained intact 

(The Nature Conservancy 2004, p. 35). 

Overall, the long-term viability of the 

Sand Mountain dune system was ranked 

marginally good, but it was noted that 

the ‘‘rapid trend towards an increasingly 

degraded condition of this area is of 

considerable concern’’ (The Nature 

Conservancy 2004, p. 35). The 

assessment noted that the condition of 

the area was primarily affected by offroad vehicle use, which was of 

particular concern because of the small 

overall size of the area and the 

likelihood of increasing use levels at the 

SMRA (The Nature Conservancy 2004, 

p. 36). It should be emphasized that this 

ranking was for the Sand Mountain 

dune ecosystem as a whole and none of 

the viability criteria evaluated 

specifically addressed either the status 

of the Sand Mountain blue butterfly or 

the Kearney buckwheat. The relevance 

of this report to the dune shrub habitat 

lies in its assessment that the process 

that supplies the source of sand to the 

ecosystem remains intact, and the 

corroboration that it provides of the 

threats posed by off-road vehicles and 

invasive weeds. 

There have been several observations 

over the past 25 years on the effects of 

off-road vehicles on the Sand Mountain 

dune shrub habitat, on the Kearney 

buckwheat, and on the relationship 

between the buckwheat habitat and the 

Sand Mountain blue butterfly. These 

include: (1) A letter documenting the 

extirpation of all plant life from an area 

150 ft (46 m) wide along the edge of the 

main dune over a period of several years 

(Giuliani 1977); (2) a memorandum from 

the Service to the BLM reporting that up 

to half of 58 individual Kearney 

buckwheat plants inspected on the 

south side of the mountain had been 

crushed and broken off at the ground 

surface and were either dead or in the 

process of resprouting from the 

rootstocks (Service 1994); (3) a mid1990’s report to the Service from a 

research scientist at the University of 

Nevada, Reno, stating that ‘‘as long as 

the foodplant remains as abundant as it 

is now in the overall dune area, we saw 

no particular threat to the continued 

existence of the butterfly’’ (Brussard 

1995). 

In our 90-day finding on the petition 

to list the Sand Mountain blue butterfly 

(71 FR 44988, August 8, 2006), we 

concluded that the petition provided 

substantial information to support the 

assertion that off-road vehicle use at 

Sand Mountain presents direct and 

indirect threats to the dune shrub 

habitat with Kearney buckwheat on 

which the Sand Mountain blue butterfly 

depends. In particular, we based our 

conclusion on the following—data 

provided by the petitioners that reliably 

documented a progressive loss of dune 

shrub habitat within the past 25 years, 

continuing fragmentation of dune shrub 

habitat, and an ongoing expansion of the 

route system into dune shrub habitat 

previously considered secure for the 

butterfly (BLM 2003); data that 

documents annual visitor use has more 

than doubled and the route system has 

expanded from 20 mi (32 km) to over 

200 mi (320 km) over this time period 

(BLM 2003); an estimate that 1,000 to 

1,600 ac (405 to 647 ha) of dune shrub 

habitat remained in which Kearney 

buckwheat is a component (BLM 2004, 

p. 4); and our estimate, based on 

satellite imagery prepared by BLM 

(2003), that about 50 percent of the dune 

shrub habitat within the species current 

range may have been destroyed or 

altered over this 25-year time span. 

The scientific literature documents 

the effects of off-road vehicles on 

terrestrial habitats in arid environments, 

including sand dunes. Effects include 

significant reductions in the number, 

density, and cover of plants, including 

shrubby perennials (Bury and 

Luckenbach 1983) and direct impacts on 

desert vegetation (Stebbins 1995; 

Lathrop 1983; Lathrop and Rowlands 

1983). While none of these citations 

provides specific evidence of a direct 

significant threat to the Sand Mountain 

blue butterfly, the papers by Bury and 

Luckenbach (1983, pp. 211–213), 

Lathrop (1983, pp. 157–164), Lathrop 

and Rowlands (1983, pp. 138–141, 144– 

146), and Stebbins (1995, pp. 471–472) 

do provide documentation that off-road 

vehicles can damage and destroy plants 

and result in significant decreases in 

plant numbers, density, and cover, 

including shrubby perennials at various 

sites in the western North American 

deserts. Specific observations of such 

impacts at Sand Mountain have been 

reported previously (Guiliani 1977; 

Service 1994; The Nature Conservancy 

2004, p. 36; BLM 2006e). 

The scientific literature provides 

documentation that natural recovery 

rates of perennial vegetative cover 

damaged by off-road vehicles in arid 

environments can take decades and, in 

some cases, may require centuries 

(Lathrop and Rowlands 1983; 

Kockelman 1983; Webb and Wilshire 

1983). The papers by Lathrop and 

Rowlands (1983, p. 143) and Kockelman 

(1983, p. 3) provide a timeframe for 

understanding natural recovery rates of 

habitats damaged by off-road vehicle 

use in arid environments. We 

previously found that these studies 

provided reliable documentation that 

even if off-road vehicle use were to be 

eliminated from Sand Mountain, natural 

recovery of the Kearney buckwheat 

habitat may take decades, a timeframe 

that might pose an indirect threat to the 

long-term viability of an obligate 

butterfly species that must reproduce 

annually and relies on the buckwheat as 

a host plant. We now have evidence, 

however, from the first comprehensive 

assessment of the status of the Sand 

Mountain blue butterfly to indicate that 

mmaher on DSK3CLS3C1PROD with $$_JOB

Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24259 

a large viable population of the species 

exists despite the past loss of habitat; 

moreover, the presence of butterflies at 

even small, relatively isolated patches of 

Kearney buckwheat suggests that the 

butterfly is not particularly sensitive to 

habitat fragmentation (Murphy et al. 

2006, pp. 5–6). 

Furthermore, as noted in the Biology 

and Distribution section, since the 

publication of the 90-day finding, we 

have obtained new information on the 

abundance and status of the Sand 

Mountain blue butterfly and the 

potential threats of habitat loss and 

fragmentation to the species. 

Researchers collected data along several 

permanent transects installed 

throughout the distribution of the dune 

shrub habitat at Sand Mountain from 

July 15 through August 9, 2006 (Murphy 

et al. 2006, pp. 4–5). The scientists 

estimated that hundreds of thousands of 

adult Sand Mountain blue butterflies 

may have emerged during the 2006 

flight season (Murphy et al. 2006, p. 7). 

Adult butterflies were associated with 

nearly all Kearney buckwheat shrubs 

along the transects and butterflies were 

distributed across the entire available 

habitat area, even with individual 

buckwheat shrubs isolated from others 

by hundreds of meters (Murphy et al. 

2006, p. 6). 

The scientists concluded the Sand 

Mountain blue butterfly numbers were 

‘‘substantially above a level that would 

indicate a need to carry out in situ or 

other actions to enhance population size 

above a critical minimum’’ (Murphy et 

al. 2006, p. 7). Annual population 

numbers may vary considerably 

depending on local weather conditions, 

and the researchers note that the large 

population in 2006 may represent an 

atypical spike in the butterfly 

population (Murphy et al. 2006, p. 9). 

However, even if this number represents 

an upper population estimate, we 

believe that the very large number of 

butterflies observed during the recent 

survey clearly shows that the remaining 

Kearney buckwheat habitat is currently 

sufficient to support a viable population 

of the Sand Mountain blue butterfly. 

Although sufficient habitat remains to 

support a robust population of the Sand 

Mountain blue butterfly (Murphy et al. 

2006, p. 7), researchers have cautioned 

that ‘‘the sizable Sand Mountain blue 

population notwithstanding, continued 

degradation of the shrub community 

and losses of Kearney buckwheat will 

ultimately lead to the elimination of the 

butterfly’’ (Murphy et al. 2006, p. 9). To 

reduce the significance of the threat 

posed to the Sand Mountain blue 

butterfly by continued degradation of 

the shrub community and losses of 

Kearney buckwheat, on December 12, 

2006, the BLM implemented an 

emergency restriction on motorized use 

on 3,985 ac (1,612 ha) of land to prevent 

further adverse effects on the habitat of 

the Sand Mountain blue butterfly (BLM 

2006b); the closure notice was 

published in the Federal Register on 

March 15, 2007 (72 FR 12187). This 

action, which reduces the route system 

both within and outside of the SMRA 

from an estimated 200 mi (320 km) to 

21.5 mi (34.4 km), has returned the 

route mileage to about the 1980 level. 

The route designation system adopted 

by BLM is consistent with the 

Conservation Plan (LVEA 2006) and the 

restrictions are described by BLM as 

necessary to prevent further adverse 

effects to the habitat of the Sand 

Mountain blue butterfly (72 FR 12187). 

The route designation system is 

specifically designed to reduce threats 

from recreational use, weed infestation, 

fire, and the reduction of site potential, 

thereby furthering the objectives of 

eliminating off-road vehicle incursions 

into dune shrub and butterfly habitat; 

preventing route increases in dune 

shrub habitat; minimizing shrub damage 

and loss; and allowing for habitat 

regeneration and restoration (LVEA 

2006, p. 15). The emergency restriction 

will remain in effect until the Resource 

Management Plan (RMP) has been 

updated to address the long-term 

management of the wildlife, cultural, 

vegetation, and recreational resources in 

the area or until the Field Office 

Manager determines it is no longer 

needed (BLM 2006b, p. 1; 72 FR 12187, 

March 15, 2007). Every indication we 

have from the BLM at both the field 

office and state office level is that the 

emergency restriction will remain in 

place until made permanent through an 

amendment to the RMP. The RMP must 

be updated in compliance with the 

Federal Land Management and Policy 

Act, the National Environmental Policy 

Act, and other applicable laws and 

policies which have, among other 

requirements, opportunity for public 

and agency review and comment. Under 

the terms of the Conservation Plan 

monitoring of compliance with the 

designated route system will continue 

and results will be reviewed every six 

months; areas in which non-compliance 

exceeds a specified threshold will be 

fenced (LVEA 2006, p. 60). 

The Conservation Plan also includes 

increased law enforcement to ensure 

compliance in the use of the designated 

route system, especially on heavy use 

weekends and randomly at other times. 

Through an agreement with Churchill 

County, which is a party to the Plan, 

local law enforcement staff will be used 

in the camping areas to allow BLM Park 

Rangers to patrol the route system and 

other areas (LVEA 2006, p. 20). Further, 

any person who fails to comply with the 

BLM restriction order may be subject to 

imprisonment for not more than 12 

months or a fine in accordance with the 

applicable provisions of 18 U.S.C. 3571, 

or both (BLM 2006b, p. 3; 72 FR 12187, 

March 15, 2007). A handout was given 

to recreational users over Labor Day 

weekend, 2006, informing them of the 

completion and approval of the 

Conservation Plan, the upcoming 

mandatory route system, and the 

importance of demonstrating success in 

protecting the habitat for the Sand 

Mountain blue butterfly (BLM 2006d). A 

variety of additional public education 

activities are provided for in the 

Conservation Plan, including 

interpretive, cautionary and regulatory 

signage throughout the SMRA and dune 

system, as well as education pamphlets, 

brochures, and information available on 

Web sites and other forms of media 

(LVEA 2006, p. 21–24). 

Implementation of the limited offroad vehicle route system is already 

occurring. We have evaluated the 

certainty of effectiveness of the 

designated route system using criteria 

specified in PECE (68 FR 15115, March 

28, 2003). Based on our evaluation, we 

have determined that this conservation 

action satisfies all of the PECE criteria 

for the certainty of effectiveness (Service 

2007). We conclude that the off-road 

vehicle route system is sufficiently 

certain to be implemented and effective 

so as to have reduced the present and 

future threat of destruction, 

modification, or curtailment of the 

habitat or range of the Sand Mountain 

blue butterfly to a level such that offroad vehicle impacts to habitat are not 

a basis for finding that listing is 

warranted. 

Other components of the 

Conservation Plan have also been 

initiated related to research (LVEA 

2006, pp. 27–28). These include 

mapping of current Kearney buckwheat 

and invasive weeds distribution; remote 

sensing of habitat characteristics, trends, 

and route analyses; studies of the Sand 

Mountain blue butterfly population 

status and habitat requirements; 

population dynamics of the Kearney 

buckwheat; and Kearney buckwheat 

propagation and transplantation studies. 

Kearney buckwheat habitat and invasive 

weeds mapping and remote sensing 

analysis of habitat characteristics, 

trends, and route analyses have been in 

progress for several years. The BLM has 

secured funding through grants to 

purchase additional imagery to continue 

mmaher on DSK3CLS3C1PROD with $$_JOB

24260 Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 

the trend analysis in 2006, 2009, and 

2012 (LVEA 2006, p. 28). Research on 

the population status of the butterfly 

was initiated during the 2006 adult 

flight season by scientists from the 

University of Nevada, Reno, with 

funding through the Nevada 

Biodiversity Initiative; these data 

provide a baseline against which future 

fluctuations in the butterfly population 

can be compared (Murphy et al. 2006). 

Pilot studies of the population dynamics 

of the Kearney buckwheat have been 

initiated (LVEA 2006, p. 27), and seed 

of the Kearney buckwheat has 

previously been collected through the 

BLM Seeds of Success program. 

Propagation studies using these seeds, 

and other seeds to be collected on site, 

are to be conducted by the Natural 

Resource Conservation Service’s newly 

established Fallon Plant Materials 

Center, which will also conduct 

transplantation studies of propagated 

seedlings into disturbed habitats at Sand 

Mountain (Tonenna 2006). While we 

did not rely on them making this 

finding, we recognized that these 

research components will both inform 

and facilitate efforts to recover damaged 

butterfly habitat at Sand Mountain as 

well as contribute to sound scientific 

data for future management actions. 

In our 90-day finding, we addressed 

the claim by the petitioners that the 

constant disruption of the soil surface 

makes it difficult or impossible for seeds 

of the Kearney buckwheat to germinate 

and for seedlings to establish and 

concluded that the petitioners had 

provided no documentation for this 

claim (71 FR 44991). The Service has 

since made field visits to Sand 

Mountain and, while we have no 

quantitative data on this matter, we 

observed an absence of Kearney 

buckwheat seedlings in areas of high 

off-road vehicle use. We also observed 

numerous Kearney buckwheat seedlings 

in areas that received little, if any, offroad vehicle use (Caicco 2006c). These 

observations are consistent with 

previous reports (Tonenna 2003 as cited 

in The Nature Conservancy 2004, p. 37). 

We believe, based on these observations, 

that the constant disruption of the sand 

surface in heavily used areas may 

interfere with the establishment of 

Kearney buckwheat and could 

potentially pose a long-term threat to 

shrub regeneration and, therefore, to the 

long-term viability of the butterfly itself. 

However, the restriction of off-road 

vehicle recreation to the designated 

route system substantially reduces the 

magnitude and imminence of the threat 

to the regeneration of Kearney 

buckwheat. As described above, 

sufficient habitat remains at Sand 

Mountain to support a large population 

of the Sand Mountain blue butterfly, 

and the reduction in the level of threat 

due to the designated route system, over 

the long-term, ensures that natural 

shrub regeneration and/or active 

restoration will maintain sufficient 

habitat to ensure the viability of the 

Sand Mountain blue butterfly. 

Although not identified as a threat by 

the petitioners, trampling or grazing of 

buckwheat plants and/or seedlings by 

livestock was identified by the working 

group as a potential threat to the habitat 

of the butterfly, although it was 

acknowledged that more information 

was needed to determine the level of 

threat (LVEA 2006, pp. 11–12). Dune 

shrub habitat with and without Kearney 

buckwheat occurs within portions of 

two range allotments, where it 

comprises 1,357 ac (549 ha), or 2 

percent, of the Salt Wells Allotment, 

and 331 ac (134 ha), or 0.5 percent, of 

the Frenchmen Flat Allotment. The 

stocking values are set at 270 cattle and 

1,626 animal unit months (AUMS) from 

October 15 through April 15 for Salt 

Wells and 403 cattle and 2,001 AUMS 

from October 15 through April 15 for 

Frenchmen Flat. We are not aware of 

any evidence that supports trampling or 

grazing as a significant threat to the 

Kearney buckwheat. 

Summary of Factor A 

Biological data on the Sand Mountain 

blue butterfly collected by researchers 

document that hundreds of thousands 

may have been present during the 2006 

adult flight season. These data show 

that a large, robust population of the 

Sand Mountain blue butterfly remains 

despite the estimated loss of as much as 

50 percent of its habitat. The only 

known threat of potential significance in 

the foreseeable future is the destruction 

by off-road vehicles of the dune shrub 

habitat containing the Kearney 

buckwheat, upon which the butterfly 

depends for its survival. Habitat 

destruction is a gradual and cumulative 

process that affects not only mature 

shrubs, but also likely disrupts their 

reproductive capacity by constant 

disturbance of the sand surface, thereby 

preventing seedling establishment. The 

shrubs, however, are long-lived and the 

habitat remains sufficiently extensive 

such that the threat to the butterfly does 

not cause it to be in danger of extinction 

nor likely to become in danger of 

extinction in the foreseeable future. 

Further, an emergency restriction on 

motorized use on 3,985 ac (1,613 ha) to 

protect the habitat of the butterfly went 

into effect on December 12, 2006 and a 

closure notice regarding these 

restrictions was published in the 

Federal Register on March 15, 2007 (72 

FR 12187). The implementation of this 

emergency restriction, and the high 

level of certainty of its effectiveness, has 

substantially reduced the magnitude 

and significance of any long-term threat 

posed by off-road vehicles to the habitat 

and viability of the Sand Mountain blue 

butterfly. Therefore, we conclude that 

the Sand Mountain blue butterfly is not 

now, or in the foreseeable future, 

threatened by destruction, modification, 

or curtailment of its habitat or range. 

Factor B: Overutilization for 

Commercial, Recreational, Scientific, or 

Educational Purposes 

We are not aware of any scientific or 

commercial data that indicate 

overutilization for commercial, 

recreational, scientific, or educational 

purposes poses a threat to the species. 

Factor C: Disease or Predation 

We are not aware of any scientific or 

commercial data that indicates either 

disease or predation poses a threat to 

the species. 

Factor D: Inadequacy of Existing 

Regulatory Mechanisms 

In our 90-day finding on the petition 

to list the Sand Mountain blue butterfly, 

we found that the petitioners had 

provided substantial information that 

existing regulatory mechanisms may be 

inadequate to prevent the progressive 

decline of the habitat on which the 

butterfly depends (page 44991 of 71 FR 

44988, August 8, 2006). We based our 

determination on evidence that the 

public had raised the issue of the 

potential impacts of off-road 

recreational use on the invertebrate 

fauna of the dune system over 25 years 

ago (Hardy 1978); the inactivity of a 

monitoring plan initiated in the mid1990’s after personnel changes in both 

the BLM and Service; the lack of action 

on a 2002 proposed closure of 1,000 ac 

(405 ha) of dune shrub habitat by a 

group comprised of BLM and Service 

staff, representatives from conservation 

and off-road vehicle groups, and 

representatives of the Fallon-Paiute 

Shoshone Tribe; and the lack of 

compliance with a voluntary route 

system implemented by the BLM in 

2004 that was intended to protect and 

restore the sand dune ecosystem. 

The inadequacy of the voluntary offroad vehicle route system is well 

documented in a monitoring report on 

compliance with the encouraged route 

system for the period 2003–2006 (BLM 

2006e). High levels of noncompliance 

occurred from the onset of 

implementation of the voluntary system, 

mmaher on DSK3CLS3C1PROD with $$_JOB

Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24261 

and the number of incursions into 

habitat outside of the encouraged routes 

increased in 2006 (BLM 2006e, pp. 3– 

4). Multiple incursions into habitat 

outside of the encouraged route system 

typically occurred at any given point, so 

that the cumulative impacts were 

considered to be four times greater than 

the number of noncompliance points 

(BLM 2006e, p. 6.). BLM’s information 

also indicates a strong relationship 

between the number of visitors and the 

number of noncompliance points (BLM 

2006e, p. 7). Moreover, about 50 percent 

of all noncompliance points occurred at 

or near red carsonite posts installed to 

alert riders that travel was discouraged 

in areas behind the posts (BLM 2006e, 

p. 8). Overall, under the voluntary 

system 98 percent of all existing routes 

continued to be used and new routes 

were created, indicating an ongoing 

expansion of habitat degradation with 

little or no restoration of previously 

degraded areas (BLM 2006e, p. 13). 

On December 12, 2006, the BLM 

implemented an emergency restriction 

on motorized use on 3,985 ac (1,613 ha) 

of land to prevent further adverse effects 

on the habitat of the Sand Mountain 

blue butterfly (BLM 2006b; 72 FR 12187, 

March 15, 2007). This action, which 

reduced the route system from an 

estimated 200 mi (320 km) to 21.5 mi 

(34.4 km), has returned the designated 

route mileage to about the 1980 level. 

The emergency restriction affects certain 

public lands within Sections 13, 14, 16, 

21 through 24, 28, 29, 32, and 33, of 

Township 17 North, Range 32 East (Mt. 

Diablo Meridian) (72 FR 12187). This 

action restricts motorized vehicle use to 

selected existing routes that generally 

lie on the periphery of the Sand 

Mountain blue butterfly habitat, 

although several existing routes remain 

open to motorized use that cross 

between existing patches of dune shrub 

habitat; the designated routes were 

selected to prevent further adverse 

effects to the habitat of the Sand 

Mountain blue butterfly while 

maintaining recreational use at the 

SMRA. This action is consistent with 

the Conservation Plan (LVEA 2006) and 

is specifically designed to address 

threats from recreational use, weed 

infestation, fire, and the reduction of 

site potential, thereby furthering the 

objectives of eliminating or reducing the 

number of off-road vehicle incursions 

into dune shrub and butterfly habitat; 

eliminate route increase in dune shrub 

habitat; eliminate shrub damage and 

loss; and allow for habitat regeneration 

(LVEA 2006, p. 15). The emergency 

restriction will remain in effect until the 

Resource Management Plan has been 

updated to address the long-term 

management of the wildlife, cultural, 

vegetation, and recreational resources in 

the area or until the Field Office 

Manager determines it is no longer 

needed (BLM 2006b, p. 1; 72 FR 12187, 

March 15, 2007). Every indication we 

have from the BLM at both the field 

office and state office level is that the 

emergency restriction will remain in 

place until made permanent through an 

amendment to the RMP. 

The Conservation Plan also provides 

for increased law enforcement, 

especially on heavy use weekends and 

randomly at other times; through an 

agreement with Churchill County, 

which is a party to the Plan, local law 

enforcement staff will be used in the 

camping areas to allow BLM Park 

Rangers to patrol the route system and 

other areas (LVEA 2006, p. 20). In 

addition, any person who fails to 

comply with this restriction order may 

be subject to imprisonment for not more 

than 12 months or a fine in accordance 

with the applicable provisions of 18 

U.S.C. 3571, or both (BLM 2006b, p. 3; 

72 FR 12187, March 15, 2007). A 

handout was given to recreational users 

over Labor Day weekend, 2006, 

informing them of the completion and 

approval of the Conservation Plan, the 

upcoming mandatory route system, and 

the importance of demonstrating 

success in protecting the habitat for the 

Sand Mountain blue butterfly (BLM 

2006d). 

The Conservation Plan includes 

provisions for regular reporting on 

progress of implementation and 

effectiveness of various actions taken 

pursuant to the plan (LVEA 2006, p. 30). 

This includes provisions for regularly 

scheduled meetings of the parties to the 

plan, at which an evaluation of the 

implementation progress and 

effectiveness of the plan (including the 

route system and its enforcement) will 

be reviewed and, if necessary, 

modifications made and adaptive 

management actions initiated. The first 

meeting of the parties since the closure 

notice was put into effect occurred on 

March 15, 2007. Implementation 

progress was reviewed, the signage and 

fencing strategy and funding 

considerations were discussed, and the 

next meeting was scheduled for May 10, 

2007. The agenda for the latter meeting 

will include further discussion of the 

fencing strategy and the scheduling of a 

site visit to discuss fence placement 

along key route segments. At every sixmonth meeting, the implementation 

success of the conservation actions will 

be evaluated, the success or failure of 

the objectives of each strategy will be 

determined and an adaptive 

management plan will be triggered, if 

appropriate. At annual meetings, the 

long-term monitoring will be analyzed 

and continuation or modification of the 

plan will be determined, based on the 

triggers for overall plan success. We 

note also that BLM has demonstrated 

their commitment to monitor the 

situation and to take appropriate action, 

as illustrated by BLM’s adoption of the 

mandatory route system based on 

monitoring of the voluntary route 

system that previously was in place. 

As described above (see discussion of 

Factor A), we reviewed the route system 

in accordance with PECE and found that 

all of the criteria for certainty of 

effectiveness are met, and concluded 

there is a high level of certainty of 

effectiveness of the route system 

(Service 2007). We conclude that the 

emergency restriction on motorized 

vehicle use has established an adequate 

regulatory mechanism to protect the 

existing Kearney buckwheat habitat 

which, as noted above, remains 

sufficient to support a large, viable 

population of the Sand Mountain blue 

butterfly (Murphy et al. 2007, p. 7). 

Summary of Factor D 

Unrestricted off-road vehicle 

recreation at Sand Mountain has been 

the primary cause of the gradual process 

of destruction and modification of the 

dune shrub habitat of the Sand 

Mountain blue butterfly over the past 

two decades and remains the only threat 

of potential significance to the species 

in the foreseeable future. However, we 

have determined that the 

implementation and effectiveness of a 

mandatory, enforceable route system 

that restricts travel within the dune 

shrub habitat adequately addresses this 

potential threat by eliminating or greatly 

reducing further habitat deterioration 

and allowing for habitat recovery within 

closed areas. We believe that the 

strengthened regulatory approach and 

increased emphasis on encouraging 

compliance with the mandatory route 

system has substantially reduced the 

magnitude and imminence of the threat 

of off-road recreational use to the 

Kearney buckwheat habitat, which 

currently remains sufficient to support a 

large, viable population of the Sand 

Mountain blue butterfly. Therefore, we 

have determined that the inadequacy of 

existing mechanisms does not currently 

constitute a threat to the Sand Mountain 

blue butterfly. 

Factor E: Other Natural or Manmade 

Factors Affecting the Continued 

Existence of the Species 

Several other natural or manmade 

factors have been identified as potential 

mmaher on DSK3CLS3C1PROD with $$_JOB

24262 Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 

threats to the Sand Mountain blue 

butterfly, including invasive weeds 

(LVEA 2006, p. 10; The Nature 

Conservancy 2004, pp. 49–52; Murphy 

et al. 2006, p. 7 and Figure 7), wildfire 

(LVEA 2006, pp. 13–14; Murphy et al. 

2006, p. 9); climate change (LVEA 2006, 

p. 14; Murphy et al. 2006, p. 9), camping 

(LVEA 2006, p. 11), hiking (LVEA 2006, 

p. 14), horseback riding (LVEA 2006, p. 

14), pollution (LVEA 2006, p. 14), and 

military action (LVEA 2006, p. 14). In 

addition, in our 90-day petition finding, 

we acknowledged that while large 

fluctuations in size typical of insect 

populations may make a species with an 

extremely limited distribution, such as 

the Sand Mountain blue butterfly, more 

susceptible to extinction (Ehrlich 1992), 

we are aware of no information that 

large population fluctuations have 

occurred, or are likely to occur for this 

species. (71 FR 44992, August 8, 2006). 

Although researchers have 

acknowledged that the large population 

observed in 2006 may have been an 

anomaly, which could have obscured 

normal patterns of butterfly distribution 

that might suggest a more significant 

threat to the species than is indicated by 

the 2006 field observation (Murphy et 

al. 2006, p. 9), they also concluded that 

the Sand Mountain blue butterfly 

numbers were ‘‘substantially above a 

level that would indicate a need to carry 

out in situ or other actions to enhance 

population size above a critical 

minimum’’ (Murphy et al. 2006, p. 7). 

Based on this assessment, we believe 

that the population will remain viable 

into the foreseeable future. 

Of the potential threats cited above, 

we consider the interrelated factors of 

invasive weeds and fire to be the most 

significant. The primary invasive weeds 

of concern at Sand Mountain are Salsola 

tragus (Russian thistle) and Bromus 

tectorum (cheatgrass). Large patches of 

both species are present in areas along 

the periphery of the sand dunes, 

principally in areas where livestock 

water tanks and camping are 

permanently located (LVEA 2006, p. 

10). Researchers did not find cheatgrass 

to be a dominant species along transects 

in 2006 (Murphy et al. 2006, Figure 5). 

The seeds of these invasive weeds can 

be spread by wind, cattle, and off-road 

vehicle transport (LVEA 2006, p. 11). 

There is no evidence that these annual 

weeds are capable of artificially 

stabilizing the dune systems at Sand 

Mountain (The Nature Conservancy 

2004, p. 53), and we do not consider 

artificial stabilization of the dune 

system to be a significant threat to the 

habitat of the Sand Mountain blue 

butterfly. We are unable to assess the 

significance of off-road vehicles as a 

vector for weed transport because of 

lack of data, although they likely 

facilitate weed establishment through 

surface disturbance. 

Because both cheatgrass and Russian 

thistle are annual plants, we do not 

believe that they pose a significant 

direct competitive threat to the Kearney 

buckwheat, a long-lived shrub. 

Cheatgrass and Russian thistle, 

however, do create a substantial fuel 

load that may increase both the 

likelihood and frequency of wildfire. 

Wildfires have not occurred over the 

past 25 years of record at Sand 

Mountain (LVEA 2006, p. 13), and 

wildfires likely have a low natural 

frequency in sparsely vegetated dune 

ecosystems. The Sand Mountain 

ecosystem was rated in fair condition 

based on the absence of known dunestabilizing invasive plants (The Nature 

Conservancy 2004, p. 35). After a 

subsequent visit by a few assessment 

team members, however, it was noted 

that the abundance of invasive plants 

was much higher than assumed by the 

team during the analysis, and it was 

possible that they might have 

downgraded the rating to poor if they 

had been aware of this information (The 

Nature Conservancy 2004, p. 37). 

Vegetation data collected along transects 

by researchers during the 2006 field 

season, however, show that both the 

presence and abundance of Russian 

thistle vary spatially, and the invasive 

weed is absent in many areas; 

nevertheless, the researchers found 

fewer butterflies where Russian thistle 

was abundant (Murphy et al. 2006, p. 7, 

Figure 7). This observation clearly 

derives from the strong correlation 

between numbers of the butterfly and 

the number of buckwheat shrubs and 

their inflorescences (Murphy et al. 2006, 

Figure 4). Transect data presented by 

the researchers appear to show that 

greater abundance of Russian thistle 

(and lesser abundance of Kearney 

buckwheat) also correlates with a 

greater abundance of several other 

plants, including four-wing saltbush, 

Oenothera deltoides (desert eveningprimrose), Rumex venosus (winged 

dock), and an unidentified species of 

wild buckwheat (Murphy et al. 2006, 

Figure 5). None of these plants are 

abundant in areas along the transects 

where the Kearney buckwheat is 

abundant (Murphy et al. 2006, Figure 5), 

suggesting the possibility that the 

particular habitats where these species, 

including Russian thistle, are dominant 

may not provide suitable habitat for the 

Kearney buckwheat. 

We conclude, therefore, that annual 

invasive weeds, the combustible fuels 

they create, and the potential for 

wildfires to occur and increase in 

frequency, thereby promoting the 

increase and establishment of invasive 

weeds, all pose risks to at least some of 

the habitat of the Sand Mountain blue 

butterfly. The extent and magnitude of 

the risks, however, is unclear because 

we have no quantitative information on 

the overall distribution and abundance 

of invasive weeds, nor are any data 

available on the response of the Kearney 

buckwheat to fire. The occurrence of the 

buckwheat in a habitat in which fire is 

naturally rare suggests that it is not firetolerant; the species, however, has an 

extensive branching caudex (root 

crown) from a deep woody taproot 

(Reveal 2002, p. 1), from which it has 

been observed to resprout after physical 

damage to its above-ground shoot 

(Service 1994). It may, therefore, be 

intolerant of fire but capable of 

surviving it. At this time, therefore, we 

are aware of no substantial evidence 

that invasive plants or fire currently 

pose a significant threat to the habitat or 

viability of the Sand Mountain blue 

butterfly. 

Of the remaining potential threats to 

the Sand Mountain blue butterfly, 

camping was identified as such 

primarily because it constitutes an 

additional source of invasive weeds 

(LVEA 2006, p. 11) and is subject to the 

same considerations discussed above. In 

addition, the only campground is 

located in an area where Kearney 

buckwheat once occurred and the 

butterfly was first discovered (Austin 

1998), but neither the buckwheat nor 

the butterfly occur there today so the 

campground itself no longer poses a 

direct threat to the species. Climate 

change is also a potential threat to the 

species (LVEA 2006, p. 14; Murphy et 

al. 2006, p. 9), but there is no available 

evidence to evaluate the imminence or 

magnitude of this threat. There is also 

no evidence that pollution or military 

action pose a significant threat to the 

species or its habitat, and their level was 

considered so low that they were not 

considered in the Conservation Plan 

(LVEA 2006, p. 14). 

Summary of Factor E 

Annual invasive weeds, the 

combustible fuels they create, and the 

potential for wildfires to occur and 

increase in frequency, thereby 

promoting the increase and 

establishment of invasive weeds all pose 

a threat to at least some of the habitat 

of the Sand Mountain blue butterfly. 

The extent and magnitude of this threat, 

however, is unclear because we have no 

quantitative information on the overall 

distribution and abundance of invasive 

mmaher on DSK3CLS3C1PROD with $$_JOB

Federal Register / Vol. 72, No. 84 / Wednesday, May 2, 2007 / Proposed Rules 24263 

weeds, nor are there any data available 

on the response of the Kearney 

buckwheat to fire. No substantial 

evidence exists to support a conclusion 

that annual weeds or fire currently pose 

a significant threat to the habitat or 

viability of the Sand Mountain blue 

butterfly. 

Finding 

We assessed the best available 

scientific and commercial information 

regarding threats faced by the Sand 

Mountain blue butterfly. We have 

reviewed the petition, information 

available in our files, and information 

submitted to us during the public 

comment period following our 90-day 

petition finding (71 FR 44988; August 8, 

2006). We also consulted with 

recognized butterfly experts and Federal 

land managers, and arranged for 

researchers to initiate field studies to 

assess the status of the subspecies and 

establish baseline data against which 

future changes in the butterfly 

population can be compared. 

Based on counts made during the 

2006 flight season, hundreds of 

thousands of adult Sand Mountain blue 

butterflies may have been present, a 

number sufficiently large for us to find 

that habitat loss to date does not pose 

a significant threat to the subspecies. 

The only known threat of potential 

future significance to the habitat of the 

Sand Mountain blue butterfly is the 

gradual destruction by off-road vehicles 

of the dune shrub habitat containing 

Kearney buckwheat, on which the 

butterfly depends, and associated 

impacts to the reproductive success of 

the shrub the constant disruption of the 

sand surface which interferes with 

seedling establishment. The magnitude 

and imminence of the threat posed by 

off-road vehicle recreation to the habitat 

of the butterfly, however, has been 

reduced by an emergency restriction 

that limits motorized vehicles to a 

designated route system that went into 

effect on December 12, 2006. We believe 

that implementation of this emergency 

restriction ensures that further habitat 

destruction is prevented and, over the 

long-term, natural shrub regeneration 

and active restoration will ensure that 

the Sand Mountain blue butterfly 

remains viable. There is no evidence 

that, based on the available information, 

other factors identified as potential 

threats, including large population 

fluctuations, invasive weeds, wildfire, 

climate change, camping, hiking, 

horseback riding, pollution, and 

military activities pose a significant 

threat to the Sand Mountain blue 

butterfly. 

The butterfly exists in only one 

population, and we consider the entire 

1,000 ac (405 ha) of dune shrub habitat 

to be the current range of the Sand 

Mountain blue butterfly; this includes 

non-Kearney buckwheat habitat through 

which the species passes, including 

areas devoid of vegetation such as trails, 

as well as areas that support the 

Kearney buckwheat shrubs on which 

the butterfly depends for completion of 

its life cycle. As described above, 

researchers have found the butterfly 

appears to co-occur with its host plant, 

Kearney buckwheat, across the entirety 

of the shrub’s distribution at Sand 

Mountain, even within small, relatively 

isolated patches of the shrub (Murphy et 

al. 2006, pp. 5–8). We believe, therefore, 

that the current range of the Sand 

Mountain blue butterfly approximates 

its historical range, although only 50 to 

60 percent of the entire area of dune 

shrub habitat is estimated to support 

substantial numbers of the Kearney 

buckwheat on which the butterfly 

depends for completion of its life cycle. 

Because the area in which the 

population exists is so small, and there 

are no unique features of the area, there 

are no areas within the species’ range 

that are significant portions of the range. 

In addition, the threats to the species are 

being addressed across its range, as 

described above, such that no area 

continues to face significant threats. 

Therefore, we find that the Sand 

Mountain blue butterfly is not 

threatened or endangered in all or a 

significant portion of its range, and 

listing it under the Endangered Species 

Act is not warranted at this time. 

We will continue to assess the status 

of the butterfly by working with the 

BLM, other parties to the Conservation 

Plan, research scientists, and other 

individuals or groups interested in 

contributing to the conservation of this 

species. We will particularly focus on 

the designated route system and the 

effectiveness of this conservation action 

in eliminating and reducing the threats 

identified to the butterfly over the 

foreseeable future. In particular, we will 

closely follow the monitoring results of 

recreational user compliance with the 

designated route system. 

As specified in PECE (68 FR 15114): 

‘‘If we make a decision not to list a 

species or to list the species based in 

part on the contributions of a formalized 

conservation effort, we will track the 

status of the effort including the 

progress of implementation and 

effectiveness of the conservation effort. 

If any of the following occurs: (1) A 

failure to implement the conservation 

effort in accordance with the 

implementation schedule; (2) a failure 

to achieve objectives; (3) a failure to 

modify the conservation effort to 

adequately address an increase in the 

severity of a threat or to address other 

new information on threats; or (4) we 

receive any other new information 

indicating a possible change in the 

status of the species, then we will 

reevaluate the status of the species and 

consider whether initiating the listing 

process is necessary. Initiating the 

listing process may consist of 

designating the species as a candidate 

species and assigning a listing priority, 

issuing a proposed rule to list, issuing 

a proposed rule to reclassify, or issuing 

an emergency listing rule.’’ 

We request that you submit any new 

information concerning the status of, or 

threats to, this species to our Nevada 

Fish and Wildlife Office (see ADDRESSES

section) whenever it becomes available. 

New information will help us monitor 

the species and encourage its 

conservation. If an emergency situation 

develops for this or any other species, 

we will act to provide immediate 

protection. 

References Cited 

A complete list of all references cited 

herein is available, upon request, from 

the Nevada Fish and Wildlife Office (see 

ADDRESSES section). 

Author 

The primary author of this notice is 

the Nevada Fish and Wildlife Office (see 

ADDRESSES). 

Authority: The authority for this action is 

section 4 of the Endangered Species Act of 

1973, as amended (16 U.S.C. 1531 et seq.). 

Dated: April 26, 2007. 

Randall B. Luthi, 

Acting Director, U.S. Fish and Wildlife 

Service. 

[FR Doc. E7–8330 Filed 5–1–07; 8:45 am] 

BILLING CODE 4310–55–P 

mmaher on DSK3CLS3C1PROD with $$_JOB