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mandate the use of such techniques for DEPARTMENT OF THE INTERIOR Public Information Solicited some, or even all, of the commercial spectrum to be auctioned in the 700 Fish and Wildlife Service When we make a finding that MHz bands. substantial information is presented to 50 CFR Part 17 indicate that listing a species may be The Public Notice also seeks comment warranted, we are required to promptly on Google’s proposal that the unpaired Endangered and Threatened Wildlife commence a review of the status of the 6 MHz E Block (722–728 MHz) in the and Plants; 90-Day Finding on a species. To ensure that the status review current Lower 700 MHz band plan Petition To List the Mt. Charleston Blue is complete and based on the best should be designated primarily or as Threatened or Endangered available scientific and commercial exclusively to be used for deployment of information, we are soliciting interactive, two-way broadband AGENCY: Fish and Wildlife Service, information on the Mt. Charleston blue services; connected to the public Interior. butterfly. We request any additional internet; and used to support innovative ACTION: Notice of 90-day petition information, comments, and suggestions software-based applications, services finding. from the public, other concerned and devices. governmental agencies, North American SUMMARY: We, the Fish and Wildlife tribes, the scientific community, E. Steps Taken To Minimize Significant Service (Service), announce a 90-day industry, or any other interested parties Economic Impact on Small Entities and finding on a petition to list the Mt. concerning the status of the Mt. Significant Alternatives Considered Charleston blue butterfly (Icaricia Charleston blue butterfly. We are shasta charlestonensis) as threatened or The RFA requires an agency to seeking information regarding the endangered under the Endangered subspecies’ historical and current status describe any significant, specifically Species Act of 1973, as amended (Act). small business, alternatives that it has and distribution, its ecology, ongoing We find that the petition presents conservation measures for the considered in reaching its proposed substantial scientific or commercial approach, which may include the subspecies and its habitat, and threats to information indicating that listing the the subspecies and its habitat. following four alternatives (among Mt. Charleston blue butterfly may be others): ‘‘(1) The establishment of warranted. Therefore, with the We will base our 12 month finding on differing compliance or reporting publication of this notice, we are a review of the best scientific and requirements or timetables that take into initiating a status review of this commercial information available, account the resources available to small subspecies, and we will issue a 12- including all information received entities; (2) the clarification, month finding to determine if the during the public comment period. If consolidation, or simplification of petitioned action is warranted. To you wish to provide comments you may compliance and reporting requirements ensure that the status review of the Mt. submit your comments and materials under the rule for such small entities; Charleston blue butterfly is concerning this finding to the Field (3) the use of performance rather than comprehensive, we are soliciting Supervisor, Nevada Fish and Wildlife design standards; and (4) an exemption scientific and commercial data Office (see ADDRESSES section). Please from coverage of the rule, or any part regarding this subspecies. A note that comments merely stating thereof, for such small entities.’’ determination on critical habitat will be support or opposition to the actions under consideration without providing The Public Notice seeks comment on made if and when a listing action is initiated for this subspecies. supporting information, although noted, the relative merits of dynamic auction will not be considered in making a techniques. The Public Notice also seeks DATES: The finding announced in the determination, as section 4(b)(1)(A) of comment on whether the Commission document was made on May 30, 2007. the Act directs that determinations as to should designate the unpaired 6 MHz E To be considered in the 12-month whether any species is a threatened or Block (722–728 MHz) in the current finding for this petition, comments and endangered species shall be made Lower 700 MHz band plan primarily or information should be submitted to us ‘‘solely on the basis of the best scientific exclusively for deployment of by July 30, 2007. and commercial data available.’’ At the broadband communications platforms. ADDRESSES: Data, information, conclusion of the status review, we will To assist the Commission in its analysis, comments, or questions concerning this issue the 12-month finding on the commenters are requested to provide petition and our finding should be petition, as provided in section information regarding how small submitted to the Field Supervisor, 4(b)(3)(B) of the Act. entities would be affected if the Nevada Fish and Wildlife Office, U.S. If you wish to comment or provide Commission were to adopt Google’s Fish and Wildlife Service, by mail at information, you may submit your proposals. Commenters should also 4701 North Torrey Pines Drive, Las comments and materials concerning this provide information on alternative Vegas, NV, 89130, or by fax at (702) finding to the Field Supervisor (see 515–5231. The petition is available at approaches to alleviate any potential ADDRESSES section). Before including burdens on small entities. http://www.fws.gov/nevada. The your address, phone number, e-mail petition, supporting data, and comments F. Federal Rules That May Duplicate, address, or other personal identifying will be available for public inspection, information in your comment, you Overlap, or Conflict With the Proposed by appointment, during normal business Rules should be aware that your entire hours at the Nevada Fish and Wildlife comment—including your personal None. Office at the above address. identifying information—may be made FOR FURTHER INFORMATION CONTACT: Federal Communications Commission. publicly available at any time. While Robert D. Williams, Field Supervisor, you can ask us in your comment to James D. Schlichting, Nevada Fish and Wildlife Office (see withhold your personal identifying Deputy Chief. ADDRESSES) (telephone 702/515–5230; information from public review, we [FR Doc. E7–10417 Filed 5–29–07; 8:45 am] facsimile 702/515–5231). cannot guarantee that we will be able to BILLING CODE 6712–01–P SUPPLEMENTARY INFORMATION: do so.

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Background identification information of the underside of the hindwing (Scott 1986, Section 4(b)(3)(A) of the Act requires petitioner, as required in 50 CFR p. 410). that the U.S. Fish and Wildlife Service 424.14(a). Weiss et al. (1997, pp. 10–11) describe the natural habitat for the Mt. (Service) make a finding on whether a Species Information Charleston blue as relatively flat petition to list, delist, or reclassify a ridgelines above 8,202 feet (2,500 species presents substantial scientific or The Mt. Charleston blue butterfly is a meters); however, isolated individuals commercial information indicating that distinctive subspecies of the wider have been observed as low as 6,562 feet the petitioned action may be warranted. ranging butterfly (Icaricia (2,000 meters). Like many butterfly This finding is based on information shasta), which is a member of species, the Mt. Charleston blue contained in the petition and (little butterfly family). The butterfly is dependent on plants both information otherwise available in our subspecies is known only from the high during larval development (larval host files at the time we make the finding. To elevations of the Spring Mountains, located approximately 25 miles (40 plants) and the adult butterfly flight the maximum extent practicable, we are period (nectar plants). The butterfly to make this finding within 90 days of kilometers (km)) west of Las Vegas in Clark County, Nevada (Austin 1980, p. requires open habitats that support our receipt of the petition, and publish Torrey’s milkvetch (Astragalus our notice of the finding promptly in the 20; Scott 1986, p. 410). Within Icaricia shasta there are six calycosus var. mancus), the only known Federal Register. larval host plant for the subspecies Our standard for substantial scientific subspecies: I. s. calchas, I. s. shasta, I. s. minnehaha, I. s. charlestonensis, I. s. (Weiss et al. 1994, p. 3; Weiss et al. or commercial information within the 1997, p. 10). Torrey’s milkvetch and Code of Federal Regulations (CFR) with pallidissima, and I. s. pitkinensis (Scott 1986, p. 410; Murphy 2006, p. 3). The Clokey fleabane (Erigeron clokeyi) are regard to a 90-day finding is ‘‘that the primary nectar plants for the amount of information that would lead first mention of I. s. charlestonensis as a unique taxon was in 1928 by Garth, subspecies; however, have a reasonable person to believe that the also been observed nectaring on measure proposed in the petition may who recognized it as distinct from the species shasta (Austin 1980, p. 20). Lemmon’s bitterweed (Hymenoxys be warranted’’ (50 CFR 424.14(b)). If we lemmonii) and Aster sp. (Boyd 2005, p. find that substantial scientific or Howe in 1975 described specimens from the Spring Mountains as I. s. shasta 1; Weiss et al. 1994, p. 3). Torrey’s commercial information was presented, milkvetch is a small, low growing, we are required to promptly commence form comstocki (Austin 1980, p. 20). However, in 1976, Ferris placed the perennial herb that grows in open areas a status review of this subspecies, if one between 5,000–10,804 feet (1,524–3,293 subspecies into the wider ranging I. s. has not already been initiated under our meters) in subalpine, bristlecone, and minnehaha (Austin 1980, p. 20). internal candidate assessment process. mixed conifer vegetation communities Finally, Austin (1980) asserted that In making this finding, we relied on of the Spring Mountains. Weiss et al. Ferris had not included populations information provided by the petitioner (1997, p. 31) describe favorable habitat from the Sierra Nevada in his study, and and otherwise available in our files at for the Mt. Charleston blue butterfly as in light of the geographic isolation and the time of the petition review. We having high densities of Torrey’s distinctiveness of the Spring Mountains evaluated this information in milkvetch, which exceed 10 plants per shasta population, and the presence of accordance with 50 CFR 424.14(b). The square meter. Good habitat contains at least three other well defined races of process of making a 90-day finding relatively little grass cover and visible under section 4(b)(3)(A) of the Act is butterflies endemic to the area, it was mineral soil (Boyd 2005, p. 1; Service based on a determination of whether the appropriate to name this population as 2006a, p. 1). information in the petition meets the the individual subspecies The Mt. Charleston blue butterfly is ‘‘substantial scientific or commercial charlestonensis (Austin 1980, p. 20). generally presumed to diapause (period information’’ threshold. This name and subspecies classification of suspended growth or development On October 20, 2005, we received a has been retained in the most recent similar to hibernation) at the base of the petition from The Urban Wildlands treatments of butterfly (Opler larval host plant or in the surrounding Group, Inc., requesting to emergency-list and Warren 2002, p. 79). substrate for at least one season (Boyd the Mt. Charleston blue butterfly The wing span of Icaricia shasta is 3⁄4 2005, p. 1). The typical flight and (Icaricia shasta charlestonensis) as a to 1 inch (19 to 26 millimeters (mm)) breeding period for the butterfly is early threatened or endangered species. In a (Opler 1999, p. 251). Males and females July to mid-August with a peak in late letter dated April 20, 2006, we of Icaricia shasta are dimorphic. The July, although the species has been responded to the petitioner that our upperside of males is dark to dull observed as early as mid-June and as initial review did not indicate that an iridescent blue, and females are brown late as mid-September (Austin 1980, p. emergency situation existed, but that if with a blue overlay. The subspecies has 22; Boyd and Austin 1999, p. 17; Forest conditions changed an emergency rule a discal black spot on the forewing and Service 2006a, p. 9). As with most could be developed. This a row of submarginal black spots on the butterflies, the Mt. Charleston blue correspondence also indicated that hindwing. The underside is gray, with butterfly typically flies during sunny funding was provided to address this a pattern of black spots, brown blotches, conditions, which are particularly petition in Fiscal Year 2006 and that we and pale wing veins to give it a mottled important for this subspecies given the anticipated making an initial finding appearance. The underside of the cooler air temperatures at high early in Fiscal Year 2007 as to whether hindwing has an inconspicuous band of elevations (Weiss et al. 1997, p. 31). or not the petition contained substantial submarginal metallic spots (Opler 1999, Excessive winds also deter flight of most information. The purpose of this finding p. 251). Based on morphology, I. s. butterflies, although Weiss et al. (1997, is to determine whether or not the charlestonensis appears to be most p. 31) speculate this may not be a petition presented substantial closely related to the Great Basin significant factor for the Mt. Charleston information regarding the status of this populations of I. s. minnehaha (Austin blue butterfly given its low-to-the- subspecies within the context of the 1980, p. 23) and can be distinguished ground flight pattern. Other than Act. The petition clearly identified itself from I. s. minnehaha by sharper and observations by surveyors, little as such and included the requisite blacker post medial spots on the information is known regarding the

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phenology of the Mt. Charleston blue 2–3 and 32; Boyd and Austin 1999, p. County, Nevada. The majority of the butterfly, as the key determinants for the 8). occurrences or observations are in the interactions between the butterfly’s Based on current and historic Lee Canyon area, with a few in Kyle flight and breeding period, larval host occurrences, the geographic range of the Canyon. Table 1 identifies the fifteen plant, and environmental conditions Mt. Charleston blue butterfly is on the separate current and historic locations have not been specifically studied. east side of the Spring Mountains, of the Mt. Charleston blue butterfly that Observations indicate that above or centered on lands managed by the are documented in the petition or below average precipitation, coupled Forest Service in the Spring Mountains identified in the State of Nevada Natural with above or below average National Recreation Area of the Heritage Program database (The Urban temperatures, influence the phenology Humboldt-Toiyabe National Forest Wildlands Group, Inc. 2005, pp. 1–3; of this subspecies (Weiss et al. 1997, pp. within Kyle and Lee Canyons, Clark Service 2006b, pp. 2–4).

TABLE 1.—LOCATIONS OR OCCURRENCES OF THE MT. CHARLESTON BLUE BUTTERFLY SINCE 1928 AND THE STATUS OF THE BUTTERFLY AT THE LOCATIONS

First/last time Location name surveyed or Status Primary references observed

1. South Loop Trail, Kyle Canyon ...... 1995/2005 Presumed extant—core colony ...... Weiss et al. 1997. 2. LVSSR #1, Lee Canyon ...... 1995/2005 Presumed extant—core colony 1 ...... Weiss et al. 1997; Boyd and Austin 2002. 3. LVSSR #2, Lee Canyon ...... 1963/2005 Presumed extant—core colony 1 ...... Austin 1980; Weiss et al. 1994; Weiss et al. 1997; Boyd and Austin 2002. 4. Foxtail Camp, Lee Canyon ...... 1998/1998 Presumed extant—ephemeral ...... Boyd and Austin 1999. 5. Youth Camp, Lee Canyon ...... 1995/1995 Presumed extant—ephemeral ...... Weiss et al. 1997. 6. Gary Abbott, Lee Canyon ...... 1995/1995 Presumed extant—ephemeral ...... Weiss et al. 1997. 7. LVSSR Parking, Lee Canyon ...... 1995/1995 Presumed extant—ephemeral ...... Weiss et al. 1997. 8. Mummy Spring, Kyle Canyon ...... 1995/1995 Presumed extant—ephemeral 2 ...... Weiss et al. 1997. 9. Lee Meadow, Lee Canyon ...... 1965/1995 Presumed extant—ephemeral ...... Weiss et al. 1997. 10. Lee Canyon holotype ...... 1963/1976 Presumed extirpated 2 ...... Austin 1963; Austin 1980; Weiss et al. 1997. 11. Cathedral Rock, Kyle Canyon ...... 1972/1972 Presumed extirpated ...... Austin 1980; Weiss et al. 1997. 12. Kyle Canyon Ski Area ...... 1965/1972 Presumed extirpated 2 ...... Austin 1980; Weiss et al. 1997. 13. Old Town, Kyle Canyon ...... 1970s/1970s Presumed extirpated 3 ...... The Urban Wildlands Group, Inc. 2005. 14. Deer Creek, Kyle Canyon ...... 1950/1950 Presumed extirpated ...... Austin 1980. 15. Willow Creek ...... 1928/1928 Presumed extirpated ...... Austin 1980; Weiss et al. 1997. 1 LVSSR = Las Vegas Ski & Snowboard Resort; LVSSR #2 is not identified as a separate site in Nevada Natural Heritage Program database (likely combined by Heritage with LVSSR #1). 2 Location is not mentioned in the petition. 3 Location is not identified in the Nevada Natural Heritage Program database.

The Service presumes that the Mt. been sighted through formal surveys or For our analysis, we define a Mt. Charleston blue butterfly is extirpated informal observation since observed in Charleston blue butterfly core colony as from a location when it has not been 1995 by Weiss et al. (1997), or formal a colony that meets the following sighted at that location through formal surveys have not occurred at that factors: (1) Contains good quality surveys or informal observation for location since the butterfly was sighted habitat, defined as habitat containing more than twenty years. We presume in 1995 by Weiss et al. (1997). As noted high densities of the host plant, Torrey’s the Mt. Charleston blue butterfly is in Table 1, the current status of the Mt. milkvetch, with little grass cover, extirpated from 6 of the 15 locations as Charleston blue butterfly is presumed particularly nonnative grass cover noted in Table 1 (The Urban Wildlands extant—ephemeral at 6 of the 15 (because grasses have been suggested as Group, Inc. 2005, pp. 1–3; Service locations or occurrences (The Urban a reason for habitat degradation or 2006b, pp. 8–9). The status of the Mt. Wildlands Group, Inc. 2005, pp. 1–3; successional changes that make habitat Charleston blue butterfly at a location is Service 2006b, pp. 7–8). unsuitable for the subspecies, see described as presumed extant— Three of the 15 historical locations are discussion below); and (2) persists as ephemeral by the Service when the presumed to be extant core colonies of habitat that maintains the location is within the extant range of the the subspecies, as adults have been metapopulation dynamics of the subspecies and is within potential identified through time and were subspecies, such that adults are recruitment distance of an extant core located during formal surveys in 1995 consistently sighted through formal or colony. The butterfly exhibits and 2005: South Loop Trail, Las Vegas informal surveys within the colony and metapopulation dynamics at these Ski and Snowboard Resort (LVSSR) #1, emigrants are provided to smaller, locations, likely emigrating to these and LVSSR #2 (see Table 1) (Weiss et al. outlying habitat patches. The amount of smaller patches of habitat from the core 1997; Boyd and Austin 2002; Boyd habitat supporting two of the three core colonies during years when 2005, p. 1; Service 2006b, p. 7; The colonies of this subspecies has been environmental conditions are favorable Urban Wildlands Group, Inc. 2005, pp. mapped using a global positioning unit (see subsequent core colonies, 1–3; Service 2006b, p. 2). The term and field-verified by the Service and metapopulation dynamics, and ‘‘core colony’’ as applied to our Forest Service; the core colony at favorable environmental conditions). At discussion of the Mt. Charleston blue LVSSR #1 occupies 2.4 acres (0.97 many of these ephemeral locations, the butterfly is used only to describe a hectares), and the core colony at LVSSR Mt. Charleston blue butterfly has not specific type of habitat for the butterfly. #2 occupies 1.3 acres (0.53 hectares),

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totaling 3.7 acres (1.5 hectares) (Service populations (Erlich et al. 1980, pp. 101– conditions in the summer of 2006. The 2006a, p. 1). The total area of the third 105; Thomas 1984, p. 344). Late season following possible explanations for the core Mt. Charleston blue butterfly snowstorms have caused alpine lack of butterfly sightings were offered colony (South Loop Trail) has not been butterfly population extinctions in by two local Mt. Charleston blue field-verified and is estimated at 5 acres Colorado (Ehrlich et al. 1972, p. 246), butterfly experts as indicated in our (2 hectares) within Kyle Canyon (The and high rainfall years have also been files. Boyd (2006, p. 1) theorizes that the Urban Wildlands Group, Inc. 2005, p. associated with population declines for Mt. Charleston blue butterfly’s host 2). Thus across its range, current other butterfly species in Europe plant, Torrey’s milkvetch, experienced estimates indicate the Mt. Charleston (Dobkin et al. 1987, p. 164). Drought, delayed emergence in the year 2005 due blue butterfly is restricted to less than late season snowstorms, unusually wet to the persistence of the snow pack well 9 acres (3.6 hectares) of core habitat, and weather, and flash flooding associated into the plant’s growing season. The the core habitat represents the only with summer monsoon thunderstorms delayed emergence of Torrey’s known occupied habitat remaining for are extreme climatic phenomena that milkvetch in 2005 could have negatively this subspecies. occur within the Spring Mountains at impacted butterfly reproduction in the Our files indicate that Boyd (2006, pp. unpredictable intervals and have been year 2005, which would equate to low 1–2) conducted focused surveys from reported as negatively affecting recruitment of emerging juveniles in the late May through August of 2006 for the numerous butterfly species in the year 2006. Boyd (2006, p. 1) further Mt. Charleston blue butterfly at all Spring Mountains, including the Mt. hypothesized that since Torrey’s extant core colonies and at extant Charleston blue butterfly, in all stages of milkvetch flowered in early May and ephemeral locations. In addition to development and their host plants June in 2006 (in response to a dry these locations, potential Mt. Charleston (Weiss et al. 1997, pp. 2–3 and 31–32; winter and spring), the emergence of the blue butterfly habitat along Griffith Boyd et al. 2000, p. 3). butterfly (typically in July) could have Peak, the South Loop Trail, North Loop The 1995 season was a boom year for again been out of synchronization with Trail, Bristlecone Trail, and South the Mt. Charleston blue butterfly (Weiss the host plant. Murphy (2006, p. 1) Bonanza Trail was also surveyed in et al. 1997, p. 32). Weiss et al. (1997, p. proposed that the localized rain events 2006. No observations of Mt. Charleston 32) commented that in 1995 almost in late June and July of 2006 could have blue butterfly were made at any every patch of host plants encountered killed any butterflies that had emerged location, including the three core during the flight season supported to date. Murphy (2006, p. 1) also colonies (Boyd 2006, p. 1). However, butterflies, including small isolated suggests that the dry winter and spring Murphy (2006, p. 1) hypothesizes that patches. The 1995 season probably may have prevented the Mt. Charleston the butterfly potentially may have a represents the maximum population blue butterfly from emerging at all. survival mechanism to adapt and size when environmental conditions Murphy (2006, p. 1) hypothesizes that remain in diapause, and therefore may were most favorable and includes both the butterfly potentially may have a be able to survive unfavorable or the larger core colonies and the smaller, survival mechanism to adapt and inclement conditions for at least one ephemeral habitat patches. In 1928 and remain in diapause, and therefore may season. 1963, the subspecies also exhibited be able to survive unfavorable or Most butterfly populations occur in higher abundances (Austin 1980, p. 22; inclement conditions for at least one roughly the same numbers from year to The Urban Wildlands Group, Inc. 2005, season. Although individuals were not year, though nearly every population p. 2). identified during surveys in 2006, we do experiences the occasional significant In contrast, the 1996 season not consider this subspecies extirpated increase or decline depending on represents a low population size for the from the three core colonies. It will be environmental conditions, and desert Mt. Charleston blue butterfly when critical for the Mt. Charleston blue species seem particularly prone to environmental conditions were butterfly to successfully reproduce and dramatic fluctuations in numbers (Scott unfavorable and very few patches of pupae to emerge in 2007. 1986, pp. 108–109). The Mt. Charleston habitat were occupied. Weiss et al. Based on information in our files, blue butterfly has been characterized as (1997, pp. 32) indicate an extremely dry most butterflies almost invariably exist particularly rare, but common in some winter may have caused poor larval host as regional metapopulations (Murphy et years as noted in the petition (Boyd and plant quality and, thus, low al. 1990, p. 44). Metapopulation Austin 1999, p. 17; The Urban overwintering success by Mt. Charleston dynamics make it difficult to interpret Wildlands Group, Inc. 2005, p. 2). As blue larvae in 1996. In addition, Weiss the true extent of the distribution of Mt. previously mentioned, variations in et al. (1997, p. 32) suggested that heavy Charleston blue butterfly. Small habitats precipitation and temperature that affect thunderstorms in early July 1996, which tend to support small populations that both the Mt. Charleston blue butterfly delivered 3 inches of rainfall in a few are frequently extirpated by events that and its larval host plant are likely hours, may have killed any Mt. are part of normal variation (Murphy et responsible for the fluctuation in Charleston blue butterflies that had al. 1990, p. 44). The continued existence population numbers between years emerged, as well as pupae waiting to of smaller populations requires the (Weiss et al. 1997, pp. 2–3 and 31–32). emerge, leading to very reduced presence of one or more large reservoir The specific requirements and timing of numbers observed in survey efforts that populations or core colonies to provide environmental conditions for larval host year. emigrants to smaller, outlying habitat plant development, and in turn Similarly, there were no sightings of patches (Murphy et al. 1990, p. 44). subspecies reproduction, is not known. the Mt. Charleston blue butterfly in Boyd and Austin (1999, p. 17) suggest Murphy et al. (1990, p. 43) note that in 2006 despite focused survey efforts. One smaller colonies of the Mt. Charleston general, extreme weather (drought, late possible explanation for the 2006 season blue butterfly may be ephemeral in the season snowstorms, unusually wet may be extreme weather; prior to 2005, long term with the larger colonies of the weather, etc.) often is the proximate there were numerous years of drought, subspecies being the only colonies to cause of declines or extinctions of followed by a record snow in the winter persist in poor, dry years. butterfly populations throughout the of 2004–2005, a dry winter and spring The Mt. Charleston blue butterfly’s world. Drought has been shown to in 2005–2006, and several localized, larval host plant, Torrey’s milkvetch, is negatively impact other butterfly high rainfall events and cloudy dependent on early successional habitat

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(Weiss et al. 1995, p. 5). Healthy overutilization for commercial, blue butterfly. This claim is supported metapopulation dynamics allow recreational, scientific, or educational by information in our files (The Urban butterflies, like the Mt. Charleston blue purposes; (C) disease or predation; (D) Wildlands Group, Inc. 2005, p. 3; butterfly, to establish new colonies in inadequacy of existing regulatory Service 2006a, pp. 1–5; Forest Service new habitat patches as vegetation mechanisms; or (E) other natural or 2004a, p. 1–3; Forest Service 2004b, p. succession renders occupied habitat manmade factors affecting its continued 9; Forest Service 2006b, pp. 1–9). Based unsuitable (Hanski and Simberloff 1997, existence. In making this finding, we on the best available information in our p. 9). Fire and avalanches are natural evaluated whether threats to the Mt. files (habitat mapping performed by disturbances that help create this Charleston blue butterfly presented in Weiss et al. (1995, Figure 8C) and mosaic of different successional states the petition may pose a concern with habitat mapping performed by the that supports the Mt. Charleston blue respect to its survival. The Act identifies Service and Forest Service in July 2006 butterfly (Weiss et al. 1995, p. 5). Forty- the five factors to be considered, either (Service 2006a, pp. 1–5)), we calculate three percent (3.7 acres (1.5 hectares)) of singly or in combination, to determine that 2.4 acres (0.97 hectares) of this core remaining habitat known to be occupied whether a species may be threatened or colony of Mt. Charleston blue butterfly by the butterfly occurs on the LVSSR, endangered. Our evaluation of these habitat remains, and we estimate that which operates on Forest Service lands threats, based on information provided the construction project associated with under a special use permit. Weiss et al. in the petition, is presented below. the replacement of the specified (1995, p. 5) observed an old avalanche snowmaking line caused the loss of 0.2 A. Present or Threatened Destruction, chute, which supports one of the three acres (0.08 hectares) of the core habitat. Modification, or Curtailment of the core colonies for this subspecies on a (3) The petition states that the Species’ Habitat or Range LVSSR ski run. Large-scale, natural construction of an avalanche deflection avalanches in the LVSSR, which could The petitioner claims that present or berm in 2000 or 2001 at the top of the have created new habitat for the threatened destruction, modification, or northwestern-most ski run (location of butterfly, have been prevented for more curtailment of the habitat or range of the the third core colony at LVSSR #2) than 40 years due to the regular use of Mt. Charleston blue butterfly threatens caused loss and degradation of core explosives in the upper portions of the this subspecies such that listing may be butterfly habitat. The location of the avalanche chutes by the LVSSR. Fire warranted. The claim is detailed in the earthen berm, and information in our suppression and other Forest Service petition by multiple instances of files that maps the Mt. Charleston blue management practices have also limited destruction or modification of the butterfly habitat on the LVSSR ski runs, the formation of new replacement subspecies’ habitat by construction and verifies this assertion (Service 2006a, habitat for the Mt. Charleston blue other activities, including: (1) Bisection pp. 1–5). butterfly. Similar losses of suitable of habitat by South Loop Trail and (4) The petition describes further habitat in woodlands and their negative unsanctioned trails created in habitat in impacts to the core colony habitat at effect on butterfly populations have Kyle Canyon; (2) resort improvements at LVSSR #2 associated with the been documented elsewhere (Thomas LVSSR #1 in Lee Canyon; (3) replacement of a snowmaking apparatus 1984, pp. 337–338). However, as construction of a berm at LVSSR #2 in or line in 2005 on a ski run east of the described in the petition, because the Lee Canyon; (4) installation and core colony, and information in our files natural processes that create and expansion of snowmaking apparatus at confirms this construction project maintain successional habitat in an LVSSR #2 in Lee Canyon; (5) small (Forest Service 2004c, p. 8). The petition early state, as required by Torrey’s construction activities at Foxtail Camp claims that lower quality peripheral milkvetch, have been limited, the in Lee Canyon; (6) expansion of the habitat for the butterfly was disturbed. LVSSR now provides important core water system at the Youth Camp in Lee Based on information in our files habitat for the Mt. Charleston blue Canyon; and (7) expansion of the regarding the extent of the disturbance butterfly (The Urban Wildlands Group, parking lot at LVSSR in Lee Canyon associated with the snowmaking line Inc. 2005, p. 2). Periodic maintenance (The Urban Wildlands Group, Inc. 2005, and other improvements in 2005, as (removal of trees and shrubs) of the ski pp. 2–3). As further detailed below, well as the mapping of Mt. Charleston runs has effectively arrested succession information in our files supports the blue butterfly habitat at LVSSR #2, the on the ski slopes and maintains the petitioner’s claim and the examples petition’s assertion is accurate (Forest early successional state favorable to the cited. Service 2006b, pp. 1–9; Service 2006a, Mt. Charleston blue butterfly; however, (1) The petition describes that Mt. pp. 1–5). Outside of the core colony the ski runs are not specifically Charleston blue butterfly habitat along habitat at LVSSR #2, peripheral habitat managed to benefit habitat for this South Loop Trail in Kyle Canyon (one of lower quality for the subspecies was subspecies and operation activities of three core colonies) is being impacted impacted by the improvements. regularly modify and remove butterfly by recreation activity, specifically (5) The petition does not present habitat. unsanctioned hiking trails. Based on specific information regarding the information in our files, an assessment extent of impact from small Threats Analysis of an unsanctioned hiking trail to a construction projects at Foxtail Camp in Section 4 of the Act and its plane crash site in the vicinity of Lee Canyon. We do not have any implementing regulations (50 CFR 424) butterfly habitat identified that the information in our files to corroborate or set forth the procedures for adding unsanctioned trail has disturbed refute the petition’s claim regarding species to the Federal List of (through loss and trampling) habitat for impacts to Mt. Charleston blue butterfly Endangered and Threatened Wildlife the Mt. Charleston blue butterfly as habitat at this location. and Plants. A species may be stated in the petition (Service 2006c, pp. (6) The petitioner also claims that the determined to be an endangered or 2–7). expansion of the water system at the threatened species due to one or more (2) The petition describes replacement Youth Camp in Lee Canyon impacted of the five factors described in section of a snowmaking apparatus or line that habitat for the Mt. Charleston blue 4(a)(1) of the Act: (A) Present or occurred within and impacted the butterfly. This assertion is confirmed by threatened destruction, modification, or habitat at LVSSR #1, another of the a Forest Service report in our files curtailment of habitat or range; (B) three core colonies of the Mt. Charleston (Forest Service 2002, pp. 16–18).

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(7) The petition identifies a location Finally, 3 of the 15 locations (estimated pp. 1–3). The following details these on the LVSSR where Mt. Charleston to encompass less than 9 acres (3.6 assertions. blue butterfly habitat was lost due to hectares) of habitat) are currently known (1) The petition alleges that modifications to a parking lot near the to be extant core colonies. Habitat loss responsibilities as described in section end of State Route 156 (The Urban and modification threatens all three of 5.6 of the Conservation Agreement have Wildlands Group, Inc. 2005, p. 3). Based these occupied core colonies, as not been met (The Urban Wildlands on data in our files, the Mt. Charleston documented by the petition and verified Group, Inc. 2005, p. 1). This section blue butterfly was first recorded at this by information in our files. We conclude states that the Forest Service and other location during 1995 surveys (Weiss et that the petition presents substantial Conservation Agreement signatories will al. 1997, p. 10), and the subspecies has information to indicate that listing may ‘‘Work with Las Vegas Ski and not been observed in the area in recent be warranted due to the present or Snowboard Resort to develop protective years (Boyd 2005, p. 1). The petition threatened destruction or modification strategies for sensitive ecological states that approximately 2 acres (0.81 of habitat or range for the Mt. Charleston resources. This will include hectares) once supported a large number blue butterfly. investigating options for erosion control of host plants for the butterfly at this B. Overutilization for Commercial, of the Lee Canyon ski slopes with native site (The Urban Wildlands Group, Inc. Recreational, Scientific or Educational seed mixes, including Astragalus 2005, p. 3). The modifications likely Purposes calycosus var. mancus to enhance occurred in 2004, when the parking area butterfly habitat, management of was used as a temporary storage pond Neither the petition nor information herbicides and pesticides, and a plan for for snowmaking water. Given our in our files provides any information eventual elimination of nonnative knowledge of the habitat requirements pertaining to Factor B with regard to the seeding, and management of the Three for the butterfly and remaining host Mt. Charleston blue butterfly. Springs area’’ (The Urban Wildlands plants around the margins of the C. Disease or Predation Group, Inc. 2005, p. 1; Forest Service parking area, the petition accurately 1998, p. 39). With a change in states that Mt. Charleston blue butterfly Neither the petition nor information ownership of the LVSSR in 2004, habitat was impacted by these in our files provides any information nonnative seeding at the LVSSR was modifications. pertaining to Factor C with regard to the eliminated. In addition, a Forest Service Present destruction, modification, or Mt. Charleston blue butterfly. decision notice dated September 13, curtailment of this subspecies’ habitat or D. Inadequacy of Existing Regulatory 2004, directed the LVSSR to prepare a range is documented by numerous Mechanisms monitoring plan for disturbed areas, activities described in the petition and which evolved into a broader Adaptive verified by information in our files. Of Although the Mt. Charleston blue Management Vegetation Plan the seven claims made in the petition butterfly is not federally listed, some (Vegetation Plan) and a specific 2005 regarding habitat loss or modification, protections are in place, as documented Program of Work (Forest Service 2004a, six were supported by information in in the petition. The subspecies is p. 2; Forest Service 2005a, pp. 1–24; our files: (1) Bisection of habitat by included in a 1998 Conservation Forest Service 2005b, pp. 1–11). One South Loop Trail and unsanctioned Agreement for the Spring Mountains purpose of this Vegetation Plan was to trails created in habitat in Kyle Canyon; National Recreation Area, Clark and Nye implement the conservation actions (2) improvements at LVSSR #1 in Lee Counties, Nevada (Conservation described in section 5.6, as well as Canyon; (3) construction of a berm at Agreement) signed by the State of Forest Service General Management LVSSR #2 in Lee Canyon; (4) Nevada, Forest Service, and the Service Plan objectives to benefit numerous installation and expansion of (Forest Service 1998, pp. 1–50). The endemic species within the LVSSR. The snowmaking apparatus at LVSSR #2 in Conservation Agreement described Vegetation Plan will guide revegetation Lee Canyon; (5) expansion of the water conservation actions for the butterfly on efforts at the LVSSR from 2005 through system at the Youth Camp in Lee lands within the Forest Service’s 2011. The objectives of this Vegetation Canyon; and (6) expansion of the jurisdiction. In 2000, the 55 species that Plan include: increase self-sustaining parking lot at LVSSR in Lee Canyon. are the subject of the Conservation populations of sensitive plants species The petition states that the current Agreement, including the Mt. and butterfly host plants; eliminate the situation of the Mt. Charleston blue Charleston blue butterfly, were use and occurrence of nonnative species butterfly is perilous, with the extant incorporated as covered species under in the ski area; describe inventory colonies all at risk of extinction (The the Clark County Multiple Species guidelines and protocols; describe Urban Wildlands Group, Inc. 2005, p. Habitat Conservation Plan (Clark County rehabilitation guidelines and protocols; 2). Based on the information in the MSHCP). describe monitoring guidelines and petition and our files, 15 locations have The petition makes three assertions protocols; and facilitate maintenance, been occupied by the Mt. Charleston that inadequacy of existing regulatory construction, and reconstruction, as blue butterfly since 1928. The mechanisms is a threat to the Mt. well as limited expansion, of skiing subspecies is presumed extirpated from Charleston blue butterfly: (1) opportunities and facilities (Forest 6 of the 15 locations. At another 6 Responsibilities as described by section Service 2005a, p. 3). Monitoring of locations, the butterfly’s occurrence is 5.6 of the Conservation Agreement have disturbed areas and control plots, and extant, but ephemeral. The butterfly not been met; (2) required butterfly targeted native seed collection, occurred exhibits metapopulation dynamics at surveys were not conducted for a project in 2005 and 2006. On-the-ground these locations, likely emigrating to at the LVSSR in 2005; and (3) no cultivation or planting of native seed these smaller patches of habitat from the mitigation for the loss of habitat from has not yet occurred. If implementation core colonies during years when projects described in the petition has of the Vegetation Plan continues with environmental conditions are favorable. occurred to meet the measurable success, the Service estimates that The Mt. Charleston blue butterfly has biological goals of no net unmitigated habitat restoration for the Conservation not been sighted at the majority of these loss under the Clark County MSHCP Agreement’s species, including the Mt. 6 extant ephemeral locations since 1995. (The Urban Wildlands Group, Inc. 2005, Charleston blue butterfly, will be

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realized in 3 to 5 years (1 to 3 more Natural Recreation Area,’’ and (b) projects described in the petition has years for seed collection and cultivation, ‘‘Maintain stable or increasing occurred. As described previously, and 2 additional years for establishment population numbers and host and larval certain responsibilities have been of habitat). This Vegetation Plan is an plant species’’ (RECON 2000a, Table initiated or met under section 5.6 of the important step towards meeting the 2.5, pp. 2–154). Conservation Agreement, although objectives of section 5.6 of the Information in our files confirms the others have not yet been initiated or Conservation Agreement, however, the petitioner’s claim that mitigation did fully implemented. Pre-activity butterfly Vegetation Plan was initiated in 2005 not occur for several projects noted in surveys were not conducted prior to and its success is yet to be determined. the petition, including: (a) The multiple construction projects at the Thus based on information in our files, expansion of the water system at the LVSSR in 2005, as described in the the petition is correct that some Youth Camp in Lee Canyon, (b) the petition and verified by information in responsibilities described in section 5.6 modification of the parking area at the our files. Mitigation for site-specific of the Conservation Agreement have not LVSSR (likely in 2004), and (c) the impacts to butterfly habitat have been been initiated or completed, such as construction of an avalanche deflection implemented for some projects, and not management of the Three Springs area, berm located at the top of the implemented for others. Now it appears and on-the-ground cultivation or northwestern-most ski run at the LVSSR that there has been a net loss of habitat planting of native seed for erosion within the LVSSR #2 core colony for the containing Mt. Charleston blue butterfly control and enhancement of butterfly Mt. Charleston blue butterfly in 2000 or larval host plant or nectar plant species habitat. However, the petition is 2001 (Forest Service 2002, pp. 15–18). in the Spring Mountains Natural incorrect with regard to other However, with regard to the projects Recreation Area as a result of responsibilities under Section 5.6 of the implemented in 2005, there is implementation of specific projects; Conservation Agreement, as some have information in our files that the Forest however, due to actions recently been fulfilled or have been initiated, Service based their permitting approval initiated, habitat restoration should be such as elimination of nonnative for these projects on implementation of realized in the future. Despite these seeding, and development of the the Vegetation Plan (Forest Service recent restoration efforts, the interim Vegetation Plan to move toward 2005a, pp. 1–24). One purpose of the loss may still be substantial due to establishing native seed and butterfly Vegetation Plan is to achieve mitigation restricted size of the occupied habitat host plants at the LVSSR. for loss of habitat from various LVSSR and the uncertain population status of (2) The petitioner alleges that project impacts to affected Conservation the subspecies. butterfly surveys were not completed for Agreement species, including the Mt. Although there are existing a project implemented in 2005 that Charleston blue butterfly. As stated agreements that intended to conserve disturbed Mt. Charleston blue butterfly above, the Vegetation Plan was initiated the Mt. Charleston blue butterfly, to date habitat at the LVSSR (The Urban in 2005 with monitoring of disturbed these agreements either have not been Wildlands Group, Inc. 2005, p. 3). areas and control plots, as well as implemented or the limited Section 1.0 of the Conservation targeted native seed collection, in 2005 implementation does not appear to have Agreement states that the Forest Service, and 2006. The Forest Service and the provided sufficient conservation for this as a general commitment, would LVSSR made the commitment to subspecies. Given the uncertain ‘‘conduct pre-activity surveys for provide for habitat restoration for population status of and 2006 survey species of concern prior to taking an projects that were implemented in 2005; results for the Mt. Charleston blue action’’ (Forest Service 1998, p. 29). however, on-the-ground cultivation or butterfly, it is necessary for the Service Information in our files confirms that planting of native seed has not yet to re-evaluate the mechanisms currently pre-activity surveys for butterflies were occurred to replace the lost Mt. in place to protect this subspecies. not completed before either a 2005 Charleston blue butterfly habitat. As Based on the above information, we find construction project associated with previously stated, if implementation of that the petition presents substantial replacing a snowmaking line that the Vegetation Plan continues with information to indicate that listing may affected the core colony at LVSSR #1, or success, the Service estimates that be warranted due to the inadequacy of other LVSSR projects implemented in habitat restoration for the Mt. existing regulatory mechanisms to 2005 (Forest Service 2004c, p. 1; Forest Charleston blue butterfly will be protect the Mt. Charleston blue Service 2005c, p. 7). realized in 3 to 5 years (1 to 3 more butterfly. (3) The petitioner also asserts that no years for seed collection and cultivation, mitigation for the loss of habitat from and 2 additional years for establishment E. Other Natural or Manmade Factors projects described in the petition has of habitat). Overall, it appears that there Affecting Its Continued Existence occurred to provide for no net has been a current net loss of Mt. The petitioner describes the threat to unmitigated loss under the Clark County Charleston blue butterfly larval host Mt. Charleston blue butterfly habitat MSHCP (The Urban Wildlands Group, plant or nectar plant species habitat in resulting from vegetation succession Inc. 2005, p. 3). As a signatory to the the Spring Mountains National and introduced plant species (The Implementing Agreement of the Clark Recreation Area as a result of specific Urban Wildlands Group, Inc. 2005, p. County MSHCP, the Forest Service projects. With successful 2). The petition provides two committed to implementing mitigation, implementation of the Vegetation Plan, illustrations of this threat: (1) The loss minimization, and monitoring actions measurable biological goals of the of habitat near Old Town in Kyle under the Clark County MSHCP for MSHCP may be met within 5 years. Canyon due to shading of the larval host covered species on Forest Service lands In summary, the petition states the plant (as a result of vegetative in Clark County. The Clark County following three points: (1) succession) and introduction of MSHCP Environmental Impact Responsibilities have not been met nonnative species including alfalfa; and Statement identifies two measurable under section 5.6 of the Conservation (2) the loss of the butterfly from Lee biological goals for the Mt. Charleston Agreement; (2) pre-activity butterfly Meadow in Lee Canyon (The Urban blue butterfly: (a) ‘‘No net unmitigated surveys were not conducted for a project Wildlands Group, Inc. 2005, p. 3). Based loss of larval host plant or nectar plant implemented in 2005; and (3) no on information in our files, Weiss et al. species habitat in the Spring Mountains mitigation for the loss of habitat from (1995, p. 5) concluded host plant

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densities in Lee Meadow appeared evaluation, we find that the petition these locations, likely emigrating to insufficient to support the Mt. does present substantial information to these smaller patches of habitat from the Charleston blue butterfly. Decreases in indicate that listing the Mt. Charleston core colonies during years when the quality or abundance of larval host blue butterfly as threatened or environmental conditions are favorable. plant and nectar sources can be caused endangered may be warranted. The Mt. Charleston blue butterfly has by changes in plant community The Mt. Charleston blue butterfly is not been sighted at the majority of these composition, particularly changes known only from the high elevations of 6 extant ephemeral locations since 1995. associated with succession, disturbance, the Spring Mountains in Clark County As described in the petition and verified and grazing regimes (Murphy et al. Nevada, where it depends upon its by information in our files, the 1990, p. 43). Changes in vegetation larval host plant, Torrey’s milkvetch. butterfly’s persistently occupied range is structure and composition associated The range of the Mt. Charleston blue currently known to be restricted to three with succession may have contributed butterfly is centered on the east side of locations or colonies on approximately to the loss of Torrey’s milkvetch, and, the Spring Mountains in Kyle and Lee 9 acres (3.6 hectares), and all three therefore, to the loss of the Mt. Canyons, on lands managed by the locations are threatened by habitat loss Charleston blue butterfly at historic sites Forest Service in the Spring Mountains and modification. We are further in Kyle Canyon (Boyd and Austin 2002, National Recreation Area of the concerned that formal surveys in 2006 p. 13). Based on information in our files, Humboldt-Toiyabe National Forest. were unable to identify any adult Weiss et al. (1997, p. 33) describe the Based on historic records and surveys, butterflies across the subspecies’ known impact of erosion control plantings of the subspecies has occupied 15 range, including at the three core grasses and alfalfa (Medicago sativa) on locations since 1928. Currently, the Mt. colonies. While we do not consider the the butterfly’s host plants at the LVSSR Charleston blue butterfly is known to species extirpated from the three core as a butterfly management issue due to occupy three core colonies in Kyle and colonies, successful reproduction and competition with butterfly host plants Lee Canyons. Two of the core colonies emergence of pupae in 2007 is critical and potential structural changes to of the subspecies in Lee Canyon total for this subspecies. 3.7 acres (1.5 hectares), while the size of butterfly habitat. Further information in There is substantial information the core colony in Kyle Canyon is our files confirmed that the LVSSR ski presented in the petition and verified by runs were seeded with both cultivated estimated at 5 acres (2 hectares); thus, information in our files that listing may varieties of native and nonnative grasses the Mt. Charleston blue butterfly is be warranted for the Mt. Charleston blue and introduced forbs in the 1970s and currently known to occupy less than 9 butterfly due to the inadequacy of 1980s (Titus and Landau 2003, pp. 1–3). acres (3.6 hectares) of habitat. The petitioner also mentions wild There is substantial information existing regulatory mechanisms (Factor horse grazing as an issue and notes that presented in the petition and verified by D). The petition describes and wild horses are nearly always present at information in our files that listing may information in our files verifies that one of the core colonies of the butterfly be warranted for the Mt. Charleston blue some responsibilities under the (LVSSR #1) (The Urban Wildlands butterfly due to the present destruction, Conservation Agreement (Sections 1.0 Group, Inc. 2005, p. 2). The petition modification, or curtailment of the and 5.6) have not been met. However, does not provide any supporting subspecies’ habitat or range (Factor A) some responsibilities under the documentation to describe this threat or and the inadequacy of existing Conservation Agreement, such as the extent of impact from the threat to regulatory mechanisms (Factor D). elimination of non-native seeding at the the Mt. Charleston blue butterfly. Based Present habitat destruction and LVSSR, have been met and still others on information in our files, the Clark modification to the Mt. Charleston blue have recently been initiated. County MSHCP identified trampling by butterfly and Torrey’s milkvetch was Furthermore, the petition describes and wild horses and livestock grazing as documented at the LVSSR in Lee information in our files verifies that potential threats to the subspecies and Canyon from multiple projects mitigation for site-specific impacts to other butterflies (RECON 2000b, p. B– implemented since 2000, including butterfly habitat have been implemented 158). The extent of any impact from construction of a berm within a core for some projects, and not implemented trampling and grazing to the Mt. colony, modifications to a parking lot, for others. It appears that currently there Charleston blue butterfly and its host and replacement of snowmaking lines has been a net loss of habitat containing plants is undocumented or unknown. (one of which affected a core colony). In Mt. Charleston blue butterfly larval host There is insufficient information in addition, expansion of the water system plant or nectar plant species in the the petition or our files to adequately at the Youth Camp in Lee Canyon Spring Mountains National Recreation characterize the threat of vegetation affected the butterfly’s habitat. Finally, Area as a result of implementation of succession, nonnative plant species, or a core colony in Kyle Canyon is bisected specific projects. Due to actions recently wild horses at the locations identified in by the South Loop Trail and is affected initiated, however, habitat restoration the petition or across the range of the by an additional unsanctioned trail. should be realized in the future. subspecies. Therefore, we conclude that The petition states that the current Although there are existing agreements there is not substantial scientific or situation of the Mt. Charleston blue in place that intended to conserve the commercial information to indicate that butterfly is perilous with the extant Mt. Charleston blue butterfly, to date listing the Mt. Charleston blue butterfly colonies all at risk of extinction (The these agreements either have not been may be warranted due to the other Urban Wildlands Group, Inc. 2005, p. implemented or the limited natural or manmade factors described in 2). Based on the information in the implementation does not appear to have the petition. petition and our files, 15 locations have provided sufficient conservation for this been occupied by the Mt. Charleston subspecies. Given the uncertain Finding blue butterfly since 1928. The population status of and the 2006 We have reviewed and evaluated the subspecies is presumed extirpated from survey results for the Mt. Charleston five listing factors with regard to the Mt. 6 of the 15 locations. At another 6 blue butterfly, it is necessary for the Charleston blue butterfly, based on the locations, the butterfly’s occurrence is Service to re-evaluate the mechanisms information in the petition and in our extant, but ephemeral. The butterfly currently in place to protect this files. On the basis of this review and exhibits metapopulation dynamics at subspecies.

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In summary, based on listing factors References Cited Authority A and D, we conclude that the petition A complete list of all references cited The authority for this action is the has presented substantial information herein is available, upon request, from Endangered Species Act of 1973, as that listing may be warranted for the Mt. the Nevada Fish and Wildlife Office (see amended (16 U.S.C. 1531 et seq.). Charleston blue butterfly. We will ADDRESSES). initiate a status review to determine Dated: May 15, 2007. whether listing the subspecies as Author H. Dale Hall, threatened or endangered is warranted. The primary author of this notice is Director, U.S. Fish and Wildlife Service. the Nevada Fish and Wildlife Office (see [FR Doc. E7–10140 Filed 5–29–07; 8:45 am] ADDRESSES). BILLING CODE 4310–55–P

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