Daily Rules, Proposed Rules, and Notices of the Federal Government
We request that you send comments only by the methods described above. We will post all comments on
This document consists of: (1) A proposed rule to list the Mount (Mt.) Charleston blue butterfly (
This rule proposes endangered status for the Mt. Charleston blue butterfly and proposes threatened status for the lupine blue butterfly, Reakirt's blue butterfly, Spring Mountains icarioides blue butterfly, and two Spring Mountains dark blue butterflies based on similarity of appearance to the Mt. Charleston blue butterfly. This rule also finds that designation of critical habitat for the Mt. Charleston blue butterfly is not prudent at this time.
• Habitat loss and degradation due to fire suppression and succession, implementation of recreation development projects and fuels reduction projects, and nonnative plant species (Factor A);
• Collection (Factor B);
• Inadequate regulatory mechanisms (Factor D); and
• Drought and extreme precipitation events, which are predicted to increase as a result of climate change (Factor E).
We have additionally determined that five species of blue butterflies warrant listing based on similarity of appearance to the Mt. Charleston blue butterfly:
• Lupine blue butterfly;
• Reakirt's blue butterfly;
• Spring Mountains icarioides blue butterfly; and
• Two Spring Mountains dark blue butterflies.
Further, we have determined that it is not prudent to designate critical habitat for the Mt. Charleston blue butterfly because the benefits are clearly outweighed by the expected increase in threats associated with a critical habitat designation:
• Publication of maps and descriptions of specific critical habitat
• Publishing the exact locations of the butterfly's habitat will further facilitate unauthorized collection and trade. Its rarity makes the Mt. Charleston blue butterfly extremely attractive to collectors; and
• Purposeful or inadvertent activities have already damaged some habitat. Many locations are difficult for law enforcement personnel to regularly access and patrol.
This document consists of: (1) A proposed rule to list the Mount (Mt.) Charleston blue butterfly (
We intend that any final action resulting from this proposed rule will be based on the best scientific and commercial data available and be as accurate and as effective as possible. Therefore, we request comments or information from the public, other concerned governmental agencies, Native American tribes, the scientific community, industry, or any other interested parties concerning this proposed rule. We particularly seek comments concerning:
(1) The species' biology, range, and population trends, including:
(a) Habitat requirements for feeding, breeding, and sheltering;
(b) Genetics and taxonomy;
(c) Historical and current range including distribution patterns;
(d) Historical and current population levels, and current and projected trends; and
(e) Past and ongoing conservation measures for the species, its habitat or both.
(2) The factors that are the basis for making a listing determination for a species under section 4(a) of the Act (16 U.S.C. 1531
(a) The present or threatened destruction, modification, or curtailment of its habitat or range;
(b) Overutilization for commercial, recreational, scientific, or educational purposes;
(c) Disease or predation;
(d) The inadequacy of existing regulatory mechanisms; or
(e) Other natural or manmade factors affecting its continued existence.
(3) Biological, commercial and noncommercial trade or collection, or other relevant data concerning any threats (or lack thereof) to this species and regulations that may be addressing those threats.
(4) Additional information concerning the historical and current status, range, distribution, and population size of this species, including the locations of any additional populations of this species.
(5) Any information on the biological or ecological requirements of the species, and ongoing conservation measures for the species and its habitat.
(6) The reasons why we should or should not designate habitat as “critical habitat” under section 4 of the Act (16 U.S.C. 1531
(7) Specific information on:
(a) The amount and distribution of Mt. Charleston blue butterfly and its habitat;
(b) What may constitute “physical or biological features essential to the conservation of the species,” within the geographical range currently occupied by the species;
(c) Where these features are currently found;
(d) Whether any of these features may require special management considerations or protection;
(e) What areas, that were occupied at the time of listing (or are currently occupied) and that contain features essential to the conservation of the species, should be included in the designation and why; and
(f) What areas not occupied at the time of listing are essential for the conservation of the species and why.
(8) Land use designations and current or planned activities in the areas occupied by the species or potential habitat and their possible impacts to the Mt. Charleston blue butterfly.
(9) Information on the projected and reasonably likely impacts of climate change on the Mt. Charleston blue butterfly or its habitat.
(10) Threats to the Mt. Charleston blue butterfly from collection of or commercial trade involving the lupine blue butterfly (
(11) Effects of and necessity of establishing the proposed 4(d) special rule to establish prohibitions on collection of, or commercial trade involving, the lupine blue butterfly, Reakirt's blue butterfly, Spring Mountains icarioides blue butterfly, and two Spring Mountains dark blue butterflies.
(12) Any foreseeable economic, national security, or other relevant impacts that may result from designating any area that may be included in the final designation. We are particularly interested in any impacts on small entities, and the benefits of including or excluding areas from the proposed designation that are subject to these impacts.
(13) Whether our approach to designating critical habitat could be improved or modified in any way to provide for greater public participation and understanding, or to assist us in accommodating public concerns and comments.
(14) The likelihood of adverse social reactions to the designation of critical habitat and how the consequences of such reactions, if likely to occur, would relate to the conservation and regulatory benefits of the proposed critical habitat designation.
Please include sufficient information with your submission (such as scientific journal articles or other publications) to allow us to verify any scientific or commercial information you include.
Please note that submissions merely stating support for or opposition to the action under consideration without providing supporting information, although noted, will not be considered in making a determination, as section 4(b)(1)(A) of the Act directs that determinations as to whether any species is a threatened or endangered species must be made “solely on the
You may submit your comments and materials concerning this proposed rule by one of the methods listed in the
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Comments and materials we receive, as well as supporting documentation we used in preparing this proposed rule, will be available for public inspection on
In 1991 and 1994, the U.S. Fish and Wildlife Service (Service) included the Mt. Charleston blue butterfly in a compilation of taxa for review and potential addition to the Lists of Endangered and Threatened Wildlife and Plants (56 FR 58804, November 21, 1991; 59 FR 58982, November 15, 1994). The Mt. Charleston blue butterfly was formerly referred to as the Spring Mountains blue (butterfly) (56 FR 58804, November 21, 1991; 59 FR 58982, November 15, 1994), but this common name is no longer used to avoid confusion with other butterflies having similar common names. In both years, the Mt. Charleston blue butterfly was assigned to “Category 2,” meaning that a proposal to list was potentially appropriate, but adequate data on biological threats or vulnerabilities were not currently available. The trend for Mt. Charleston blue butterfly was described as “declining” in 1991 and 1994 (56 FR 58804; 59 FR 58982). These notices stressed that Category 2 species were not proposed for listing by the notice, nor were there any plans to list those Category 2 species unless supporting information became available.
In the February 28, 1996, Candidate Notice of Review (61 FR 7595), we adopted a single category of candidate defined as “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 Candidate Notices of Review, species and subspecies matching this 1996 definition were known as Category 1 candidates for listing. Thus, the Service no longer considered Category 2 species and subspecies as candidates and did not include them in the 1996 or any subsequent Candidate Notices of Review. The decision to stop considering Category 2 species and subspecies as candidates was designed to reduce confusion about the status of these species and subspecies and to clarify that we no longer regarded these species and subspecies as candidates for listing.
On October 20, 2005, we received a petition dated October 20, 2005, from The Urban Wildlands Group, Inc., requesting that we emergency list the Mt. Charleston blue butterfly as an endangered or threatened species. In a letter to the petitioner dated April 20, 2006, we stated that our initial review did not indicate that an emergency situation existed, but that if conditions changed, an emergency rule could be developed. On May 30, 2007, we published a 90-day petition finding (72 FR 29933) in which we concluded that the petition provided substantial information indicating that listing of the Mt. Charleston blue butterfly may be warranted, and we initiated a status review. On April 26, 2010, CBD amended its complaint in
It is our intent to discuss below only those topics directly relevant to the listing of the Mt. Charleston blue butterfly as an endangered species in this section of the proposed rule.
The Mt. Charleston blue butterfly is a distinct subspecies of the wider ranging Shasta blue butterfly (
Our use of the genus name
As a subspecies, the Mt. Charleston blue butterfly is similar to other Shasta blue butterflies, with a wingspan of 0.75 to 1 inch (in) (19 to 26 millimeters (mm)) (Opler 1999, p. 251). Males and females of Mt. Charleston blue are dimorphic (occurring in two distinct forms). The upperside of males is dark to dull iridescent blue, and females are brown with a blue overlay. The species has a discal black spot on the forewing and a row of submarginal black spots on the hindwing. The underside is gray, with a pattern of black spots, brown blotches, and pale wing veins to give it a mottled appearance. The underside of the hindwing has an inconspicuous band of submarginal metallic spots (Opler 1999, p. 251). Based on morphology, the Mt. Charleston blue butterfly is most closely related to the Great Basin populations of Minnehaha blue butterfly (Austin 1980, p. 23), and it can be distinguished from other Shasta blue butterfly subspecies by the presence of sharper and blacker postmedian spots on the underside of the hindwing (Scott 1986, p. 410).
The Mt. Charleston blue butterfly is similar in appearance to five other sympatric (occupying the same or overlapping geographic areas without interbreeding) butterflies that occur roughly in the same habitats: lupine blue butterfly (
Based on current and historical occurrences or locations (Austin 1980, pp. 20-24; Weiss
We presume that the Mt. Charleston blue butterfly is extirpated from a location when it has not been recorded at that location through formal surveys or informal observation for more than 20 years. We selected a 20-year time period because it would likely allow for local extirpation and recolonization events (metapopulation dynamics) to occur and would be enough time for succession or other vegetation shifts to render the habitat unsuitable (see discussion in Biology and Habitat sections below). Using this criterion, the Mt. Charleston blue butterfly is considered to be “presumed extirpated” from 6 of the 16 known locations (Locations 11-16 in Table 1) (Service 2006b, pp. 8-9). Of the remaining 10 locations, 8 locations or occurrences are “presumed occupied” by the subspecies (Locations 3-10 in Table 1) and the first 2 locations are “known occupied” (Locations 1-2 in Table 1) (Service 2006b, pp. 7-8). We note that the probability of detection of Mt. Charleston blue butterflies at a particular location in a given year is affected by factors other than the butterfly's abundance, such as survey effort and weather, both of which are highly variable from year to year.
The presumed occupied category is defined as a location within the current known range of the subspecies where adults have been intermittently observed and there is a potential for diapausing (a period of suspended growth or development similar to hibernation) larvae to be present. The butterfly likely exhibits metapopulation dynamics at these locations. In this situation, the subspecies is subject to local extirpation, with new individuals emigrating from nearby “known occupied” habitat, typically during years when environmental conditions are more favorable to emergence from diapause and the successful reproduction of individuals (see discussion in
We consider the remaining two Mt. Charleston blue butterfly locations or occurrences to be “known occupied” (Locations 1 and 2 in Table 1). Known occupied locations have had successive observations during multiple years of surveys and occur in high-quality habitat. The South Loop Trail location in Upper Kyle Canyon (Location 1 in Table 1) is considered known occupied because: (1) The butterfly was observed on the site in 1995, 2002, 2007, 2010, and 2011 (Service 2007, pp. 1-2; Kingsley 2007, p. 5; Pinyon 2011, pp. 17-19; Thompson
We consider the Las Vegas Ski and Snowboard Resort location (LVSSR) in Upper Lee Canyon (Location 2 in Table
While there are no estimates of the size of the Mt. Charleston blue butterfly population, the best available information indicates a declining trend for this subspecies, as discussed below. Prior to 1980, descriptions of the Mt. Charleston blue butterfly status and trends were characterized as usually rare (Austin and Austin 1980, p. 30). The Mt. Charleston blue butterfly is known to be rare because few have been observed since the 1920's, even though there have been many collections and studies of butterflies in the Spring Mountains, particularly since the 1950's (Boyd and Austin 1999, p. 2).
It is important to note that year-to-year fluctuations in population numbers do occur (most likely due to variations in precipitation and temperature that affect both the Mt. Charleston blue butterfly and its larval host plant (Weiss
Survey information indicates that the numbers of recently observed Mt. Charleston blue butterflies are extremely low because butterflies have become increasingly difficult to detect. Zonneveld
In 2006, Boyd (2006, pp. 1-2) conducted focused surveys for the subspecies at nearly all previously known locations and within potential habitat along Griffith Peak, North Loop Trail, Bristlecone Trail, and South Bonanza Trail but did not observe the butterfly at any of these locations. In 2007, surveys were again conducted in previously known locations in Upper Lee Canyon and LVSSR, but no butterflies were recorded (Datasmiths 2007, p. 1; Newfields 2008, pp. 21-24). In 2007, two Mt. Charleston blue butterflies were sighted on different dates at the same location on the South Loop Trail in Upper Kyle Canyon (Kingsley 2007, p. 5). In 2008, butterflies were not observed during focused surveys of Upper Lee Canyon and the South Loop Trail (Boyd and Murphy 2008, pp. 1-3; Boyd 2008, p. 1; SWCA 2008, p. 6), although it is possible that adult butterflies may have been missed on the South Loop Trail because the surveys were performed very late in the season. No formal surveys were conducted in 2009; however, no individuals were observed during the few informal attempts made to observe the species (Service 2009).
In 2010, the Mt. Charleston blue butterfly was observed during surveys at LVSSR and the South Loop Trail area. One adult was observed in Lee Canyon at LVSSR on July 23, 2010, but no other adults were detected at LVSSR during surveys conducted on August 2, 9, and 18, 2010 (Thompson and Garrett 2010, pp. 4-5). The Mt. Charleston blue butterfly was not observed at LVSSR in 2011 (Thompson
The best available habitat information relates mostly to the Mt. Charleston blue butterfly's larval host plant, with little to no information available characterizing the butterfly's interactions with its known nectar plants or other elements of its habitat; thus, the habitat information discussed in this document centers on
Fire suppression and other management practices have likely limited the formation of new habitat for the Mt. Charleston blue butterfly, as discussed below. The Forest Service began suppressing fires on the Spring Mountains in 1910 (Entrix 2007, p. 111). Throughout the Spring Mountains, fire suppression has resulted in higher densities of trees and shrubs (Amell 2006, pp. 2-3) and a transition to a closed-canopy forest with shade-tolerant understory species (Entrix 2007, p. 112) that is generally less suitable for the Mt. Charleston blue butterfly. Boyd and Murphy (2008, pp. 23 and 25) hypothesized that the loss of presettlement vegetation structure over time has caused the Mt. Charleston blue butterfly's metapopulation dynamics to collapse in Upper Lee Canyon. Similar losses of suitable butterfly habitat in woodlands and their negative effect on butterfly populations have been documented (Thomas 1984, pp. 337-338). The disturbed landscape at LVSSR provides important habitat for the Mt. Charleston blue butterfly (Weiss
The Mt. Charleston blue butterfly has been described as biennial where it diapauses as an egg the first winter and as a larvae near maturity the second winter (Ferris and Brown, pp. 203-204; Scott 1986, p. 411); however, Emmel and Shields (1978, p. 132) suggested that diapause was passed as partly grown larva because freshly hatched eggshells were found near newly laid eggs (indicating that the eggs do not overwinter). The Mt. Charleston blue butterfly is generally thought to diapause at the base of its larval host plant,
The typical flight and breeding period for the butterfly is early July to mid-August with a peak in late July, although the subspecies has been observed as early as mid-June and as late as mid-September (Austin 1980, p. 22; Boyd and Austin 1999, p. 17; Forest Service 2006a, p. 9). As with most butterflies, the Mt. Charleston blue butterfly typically flies during sunny conditions, which are particularly important for this subspecies given the cooler air temperatures at high elevations (Weiss
Like all butterfly species, both the phenology (timing) and number of Mt. Charleston blue butterfly individuals that emerge and fly to reproduce during a particular year are reliant on the combination of many environmental factors that may constitute a successful (“favorable”) or unsuccessful (“poor”) year for the subspecies. Other than observations by surveyors, little information is known regarding these aspects of the subspecies' biology, since the key determinants for the interactions among the Mt. Charleston blue butterfly's flight and breeding period, larval host plant, and environmental conditions have not been specifically studied. Observations indicate that above- or below-average precipitation, coupled with above- or below-average temperatures, influence the phenology of this subspecies (Weiss
Most butterfly populations exist as regional metapopulations (Murphy
Section 4 of the Act (16 U.S.C. 1533), and its implementing regulations at 50 CFR part 424, set forth the procedures for adding species to the Federal Lists of Endangered and Threatened Wildlife and Plants. Under section 4(a)(1) of the Act, we may list a species based on any of the following five factors: (A) The present or threatened destruction, modification, or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) the inadequacy of existing regulatory mechanisms; and (E) other natural or manmade factors affecting its continued existence. Listing actions may be warranted based on any of the above threat factors, singly or in combination. Each of these factors is discussed below.
Below, we evaluate several factors that negatively impact the Mt. Charleston blue butterfly's habitat, including fire suppression, fuels reduction, succession, introduction of nonnative species, recreation, and development. We also examine available conservation measures in the form of conservation agreements and plans, which may offset some of these threats.
Butterflies have extremely specialized habitat requirements (Thomas 1984, p. 337). Changes in vegetation structure and composition as a result of natural processes are a serious threat to butterfly populations because these changes can disrupt specific habitat requirements (Thomas 1984, pp. 337-341; Thomas
Datasmiths (2007, p. 21) also suggest suitable habitat patches of
Fire suppression in the Spring Mountains has resulted in long-term successional changes, including increased forest area and forest structure (higher canopy cover, more young trees, and more trees intolerant of fire) (Nachlinger and Reese 1996, p. 37; Amell 2006, pp. 6-9; Boyd and Murphy 2008, pp. 22-28; Denton
Boyd and Murphy (2008, p. 23) note that important habitat characteristics required by Mt. Charleston blue butterfly—
The introduction of forbs, shrubs, and nonnative grasses can be a threat to the butterfly's habitat because these species can compete with, and decrease, the quality and abundance of larval host plant and adult nectar sources. This has been observed for many butterfly species including the Quino checkerspot butterfly (
Introduction of nonnative species within its habitat negatively impacts the quality of the Mt. Charleston blue butterfly's habitat. As mentioned previously (see Habitat section), periodic maintenance (removal of trees and shrubs) of the ski runs has effectively arrested succession on the ski slopes and maintains conditions that can be favorable to the Mt. Charleston blue butterfly. However, the ski runs are not specifically managed to benefit habitat for this subspecies and its habitat requirements, and operational activities (including seeding of nonnative species) regularly modify Mt. Charleston blue butterfly habitat or prevent host plants from reestablishing in disturbed areas. According to Weiss
The best available information indicates that, in at least four of the six locations where the Mt. Charleston blue butterfly historically occurred, suitable habitat is no longer present due to vegetation changes attributable to succession, the introduction of nonnative species, or a combination of the two.
As discussed in the
Three future projects also may impact Mt. Charleston blue butterfly habitat in Upper Lee Canyon. These projects are summarized below:
(1) A March 2011 Master Development Plan for LVSSR proposes to improve, upgrade, and expand the existing facilities to provide year-round recreational activities. The plan proposes to increase snow trails, beginner terrain, and snowmaking reservoir capacity and coverage, widen existing ski trails, replace and add lifts, and develop “gladed” areas for sliding that would remove deadfall timber to reduce fire hazards (Ecosign 2011, I-3—I-4, IV-5—IV-7). The plan proposes to add summer activities including lift-accessed sightseeing and hiking, nature interpretive hikes, evening stargazing, mountain biking, conference retreats and seminars, weddings, family reunions, mountain music concerts, festivals, climbing walls, bungee trampoline, beach and grass volleyball, a car rally, and other activities (Ecosign 2008, pp. I-3—I-4). Widening existing ski trails and increasing snowmaking reservoir capacity (Ecosign 2011, p. IV-5, Figure 21a) would impact the Mt. Charleston blue butterfly at a known occupied and at a presumed occupied location (Location 2 and 5 in Table 1). Summer activities would impact the Mt. Charleston blue butterfly and its known occupied and presumed occupied habitat by attracting visitors in higher numbers during the time of year when larvae and host plants are especially vulnerable to trampling (Location 2 in Table 1). The LVSSR Master Development Plan, which has been accepted by the Forest Service, considered Mt. Charleston blue butterfly habitat during development of the plan. Impacts to Mt. Charleston blue butterfly habitat from the LVSSR Master Development Plan will be addressed further during the National Environmental Policy Act (NEPA) process (discussed further in Factor D) (Forest Service 2011a, p. 3).
(2) The Old Mill/Dolomite/McWilliams Reconstruction Projects to improve camping and picnic areas in Upper Lee Canyon are currently being planned and evaluated under NEPA (discussed further in Factor D) (Forest Service 2011c pp. 1-4). Project details are limited because planning is currently underway; however, the Service has met with the Forest Service and provided recommendations to consider for analysis of potential direct and indirect impacts of these projects to the Mt. Charleston blue butterfly and its potential habitat within or in close proximity to the project area (Datasmiths 2007, Figure 1; Forest Service 2011c, Project Map; Forest Service 2011f, pp. 1-5; Service 2011, p. 1). The recommendations provided by the Service will assist with the development of a proposed action that will avoid or minimize adverse effects to the Mt. Charleston blue butterfly and its potential habitat.
(3) The Foxtail Group Picnic