Federal Register: December 19, 2006 (Volume 71, Number 243)
DOCID: FR Doc E6-21135
DEPARTMENT OF THE INTERIOR
U.S. Citizenship and Immigration Services
CFR Citation: 50 CFR Part 17
NOTICE: Part IV
DOCUMENT ACTION: Notice of 90-day petition finding.
SUBJECT CATEGORY:
Endangered and Threatened Wildlife and Plants; 90-Day Finding on Petitions to List the Mono Basin Area Population of the Greater Sage- Grouse as Threatened or Endangered
DATES: This finding was made on December 19, 2006.
DOCUMENT SUMMARY:
We, the U.S. Fish and Wildlife Service (Service), announce a 90day finding on two petitions to list the Mono Basin area population of greater sagegrouse (Centrocercus urophasianus) in the BiState area of California and Nevada as threatened or endangered under the Endangered Species Act of 1973, as amended. We find that the petitions do not present substantial scientific or commercial information indicating that listing this population may be warranted. Therefore, we are not initiating a status review in response to these petitions. We ask the public to submit to us any new information that becomes available concerning the status of this population or threats to it or its habitat at any time.
SUMMARY:
Interior Department, Fish and Wildlife Service,
SUPPLEMENTAL INFORMATION
Background
Section 4(b)(3)(A) of the Endangered Species Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.), requires that the Service make a finding on whether a petition to list, delist, or reclassify a species presents substantial scientific or commercial information indicating that the petitioned action may be warranted. Such findings are based on information contained in the petition and information otherwise available in our files at the time we make the determination. To the maximum extent practicable, we are to make this finding within 90 days of our receipt of the petition, and publish our notice of the finding promptly in the Federal Register.
In making this finding, we based our decision on information provided by the petitioners in petitions dated December 28, 2001, and November 10, 2005, and otherwise available in our files at the time of the petition review. As part of an active and ongoing partnership with the States of California and Nevada in collaborative sagegrouse conservation efforts, we contacted the Nevada Department of Wildlife (NDOW) and the California Department of Fish and Game (CDFG) subsequent to receiving the 2005 petition, to obtain information about sagegrouse for the Mono Basin area, as sagegrouse are a game species managed by the States. We received information from these agencies on population levels, lek distribution, harvest and harvest seasons, and implementation of projects of benefit to sagegrouse. We also contacted the U.S. Geological SurveyBiological Resources Division (USGSBRD), Dixon Field Station of the Western Ecological Research Center, to obtain reports from a 3year study of sagegrouse in the BiState area that was mostly funded by the CDFG and the Service. New information (i.e. information not already in our files) obtained from NDOW, CDFG, and USGSBRD as a result of these contacts, was not used as a basis for this 90day finding. Specifically we did not utilize the new information we obtained in our evaluation of threats (see Threats Analysis, below), which is the basis of this finding. This approach is consistent with recent court decisions that invalidated the Service's 90day findings for the Yellowstone cutthroat trout (Center for Biological Diversity, et al v. Morgenweck, 351 F. Supp. 2d 1137, 1143 44 (D. Colo. 2004)) and the Colorado River cutthroat trout (Colorado River Cutthroat Trout, et al. v. Kempthorne et al., No. 002497, slip op. at 12 (D. D.C. September 7, 2006)). In these cases, the courts ruled that the Service overreached the limited review involved in a 90finding by soliciting information from State and Federal agencies after the receipt of the petition and relied on that information to supplement petition findings. Therefore, the Service did not rely on any new information received from the States or from USGSBRD in the threats analysis. We have however, included some of the new information in the Species Information section (see below) to help the public understand the status of the population.
We evaluated the information in the petitions in accordance with our regulations at title 50 of the Code of Federal Regulations (CFR), Sec. 424.14(b). The process of making a 90day finding under section 4(b)(3)(A) of the Act and Sec. 424.14(b) of our regulations is based on a determination of whether the information in the petition meets the ``substantial scientific information'' threshold.
Our standard for substantial scientific or commercial information with regard to a 90day petition finding is ``that amount of information that would lead a reasonable person to believe that the measure proposed in the petition may be warranted'' (50 CFR 424.14(b)). If we find that the petition presents substantial scientific or commercial information, we are required to promptly commence a status review of the species.
On January 2, 2002, we received a petition, dated December 28, 2001, from the Institute for Wildlife Protection requesting that the greater sage grouse (Centrocercus urophasianus phaios) occurring in the Mono Basin area of Mono County, California, and Lyon County, Nevada, be emergency listed as an endangered distinct population segment (DPS) under the Act. Although the petitioner referred to greater sagegrouse in the Mono Basin area by the subspecific epithet ``phaios'' we have concluded that the subspecies designations for greater sagegrouse are inappropriate give current taxonomic standards (September 12, 2006, Federal Register, p. 53781). In response to recent judicial direction, the Service is in the process of revisiting our current interpretation of the taxonomic status of the greater sagegrouse subspecies. We have not included subspecies designations any further in this finding.
The petition clearly identified itself as such and included the
requisite identification information for the petitioners, as required
in 50 CFR 424.14(a). In a March 20, 2002, letter to the petitioners, we
responded that we reviewed the petition and determined that an
emergency listing was not necessary. On December 26, 2002, we published
a 90day finding that this petition did not present substantial
scientific or commercial information indicating that the petitioned
action may be warranted (67 FR 78811). Our finding was based the lack
of substantial information in the petition indicating that the Mono
basin area sagegrouse is a distinct population segment (DPS) under our
DPS policy (61 FR 47222), and thus we concluded it was not a listable
entity (Federal Register, December 26, 2002, pp. 7881378814). [[Page 76059]]
Our 2002 finding also included a determination that the petition did
not present substantial information that the Mono Basin area sage
grouse was threatened with extinction (Federal Register, December 26, 2002, p. 78814).
On November 15, 2005, we received a formal petition dated November 10, 2005, submitted by the Stanford Law School Environmental Law Clinic on behalf of the Sagebrush Sea Campaign, Western Watersheds Project, the Center for Biological Diversity, and Christians Caring for Conservation to list the Mono Basin area greater sagegrouse (Centrocercus urophasianus) as threatened or endangered. The petition clearly identified itself as a petition and included the requisite identification information for the petitioners, as required in 50 CFR 424.14(a). In a March 28, 2006, letter to the petitioners, we responded that we reviewed the petition and determined that emergency listing was not warranted. We also stated that due to court orders and settlement agreements for other listing and critical habitat actions that required nearly all of our listing and critical habitat funding for fiscal year 2006, we would not be able to further address the petition at that time. On April 17, 2006, we received a 60day notice of intent letter from the Stanford Environment Law Clinic, dated April 14, 2006, notifying us that the petitioners intend to sue the Service for violating the Act's requirement to make a petition finding within 12 months after receiving a petition.
On November 18, 2005, the Institute for Wildlife Protection and Dr. Steven G. Herman filed a Complaint for Declaratory and Injunctive Relief in United States District Court for the Western District of Washington (Institute for Wildlife Protection et al. v. Norton et al., No. C051939 RSM) challenging the Service's finding in 2002 that their petition did not present substantial information indicating that the petitioned action may be warranted. On April 11, 2006, we reached a stipulated settlement agreement with the plaintiffs. Under this settlement agreement we agreed to evaluate both the November 2005 petition submitted by the Sagebrush Sea Campaign, Western Watersheds Project, the Center for Biological Diversity, and Christians Caring for Conservation (hereafter referred to as the November, 2005 petition), and to reconsider the December 2001 petition submitted by the Institute for Wildlife protection (hereafter referred to as the December, 2001 petition). The settlement agreement calls for the Service to submit to the Federal Register a completed 90day finding by December 8, 2006, and if substantial, to complete the 12month finding by December 10, 2007. This notice constitutes the 90day finding on the November 2005 petition and reevaluation of the December 2001 petition. In completing this finding, we reviewed the December 2001 petition in the context of whether it provided additional information not discussed in the November 2005 petition.
Species Information
The sagegrouse is the largest North American grouse species. Adult males range in size from 65 to 75 centimeters (cm) (26 to 30 inches (in)) and weigh between 1.7 and 2.9 kilograms (kg) (3.8 and 6.4 pounds (lb)); adult females range in size from 50 to 60 cm (19.7 to 23.6 in) and weigh between 1 and 1.8 kg (2.2 and 3.9 lb) (Schroeder et al. 1999, p. 1920). Males and females have dark grayishbrown body plumage with many small gray and white speckles, fleshy yellow combs over the eyes, long pointed tails, and darkgreen toes (Schroeder et al. 1999, p. 2). Males also have blackish chin and throat feathers, conspicuous phylloplumes (specialized erectile feathers) at the back of the head and neck, and white feathers forming a ruff around the neck and upper belly. During breeding displays, males also exhibit olivegreen apteria (fleshy bare patches of skin) on their breasts (Schroeder et al. 1999, p. 2).
Sagegrouse depend on a variety of shrub steppe habitats throughout their life cycle, and are particularly associated with several species of sagebrush (Artemisia spp.). Throughout much of the year, adult sage grouse rely on sagebrush to provide roosting cover and food (Schroeder et al. 1999, p. 4). During the winter, they depend almost exclusively on sagebrush for food (Schroeder et al. 1999, p. 5). The type and condition of shrub steppe plant communities strongly affect habitat use by sage grouse populations. However, these populations also exhibit strong site fidelity. Sagegrouse populations may disperse up to 160 kilometers (km) (100 miles (mi)) between seasonal use areas; however, average population movements are generally less than 34 km (21 mi) (Schroeder et al. 1999, p. 3). Movements between season use areas may involve dispersal over areas of unsuitable habitat.
During the spring breeding season, primarily during the morning hours just after dawn, male sagegrouse gather together and perform courtship or strutting displays on areas called leks (an area where animals assemble and perform courtship displays) (Connelly et al. 2004, p. 38). Areas of bare soil, short grass steppe, windswept ridges, exposed knolls, or other relatively open sites may serve as leks (Connelly et al. 2004, p. 37). Leks range in size from 1 hectare (ha) (2.5 acre (ac)) to at least 16 ha (39.5 ac) (Connelly et al. 2004, p. 37) and can host several to hundreds of males. Some leks are used for many years. These ``historic'' leks are typically surrounded by smaller ``satellite'' leks, which may be less stable in both size and location within the course of 1 year and between 2 or more years. A group of leks where males and females may interact within a breeding season (approximately late February to early June each year) or between years is called a lek complex. Males defend individual territories within leks and perform elaborate displays with their specialized plumage and vocalizations to attract females for mating (Connelly et al. 2004, pp. 37 to 38).
Females may travel over 20 km (12.5 mi) after mating, and typically select nest sites under sagebrush cover, although other shrub or bunchgrass species are sometimes used (Connelly et al. 2000, p. 970). Nests are relatively simple and consist of scrapes on the ground. Clutch sizes range from about 69 eggs (Connelly et al. 2004, p. 310). Nest success ranges from 12 to 86 percent (Connelly et al. 2000, p. 969). Sage grouse generally have low reproductive rates and high annual survival compared to other grouse species (Connelly et al. 2000, p. 970). Shrub canopy and grass cover provide concealment for sage grouse nests and young, and may be critical for reproductive success (Connelly et al. 2000, p. 971).
Sagegrouse typically live between 1 and 4 years. However, sage grouse up to 10 years of age have been recorded in the wild (Connelly et al. 2004, p. 312). Annual survival ranges from about 36 to 78 percent for females and about 30 to 60 percent for males (Connelly et al. 2004, p. 312). The generally higher survival rate of females accounts for a femalebiased sex ratio in adult birds (Schroeder et al. 1999, p. 14).
Prior to settlement of the western United States by European
immigrants greater sagegrouse were found in 13 States and 3 Canadian
provincesWashington, Oregon, California, Nevada, Idaho, Montana,
Wyoming, Colorado, Utah, South Dakota, North Dakota, Nebraska, Arizona,
British Columbia, Alberta, and Saskatchewan (Schroeder et al. 2004, p.
368). Greater sagegrouse still occur in most of these states and
provinces except for Nebraska, British Columbia, and possibly Arizona
where they have been extirpated (Schroeder et al. 2004, pp. [[Page 76060]]
368369). Sagebrush habitats that potentially supported greater sage
grouse covered approximately 1,200,483 square kilometers (sq km)
(463,509 square miles (sq mi)) before the year 1800 (Schroeder et al.
2004, p. 366). Current distribution is estimated at 668,412 sq km
(258,075 sq mi) or 56 percent of the potential presettlement distribution (Schroeder et al. 2004, p. 369).
The number of greater sagegrouse that existed in North America prior to European expansion across the continent is unknown. The Western States Sage and Columbian SharpTailed Grouse Technical Committee (WSSCSTGTC) estimated there were 1.1 million sagegrouse in 1800 (WSSCSTGTC 1999), although this estimate was for both greater sagegrouse and Gunnison sagegrouse (Centrocercus minimus). Braun (1998, unpaginated) estimated that there were about 142,000 sagegrouse (both greater and Gunnison sagegrouse) rangewide in 1998. Connelly et al. (2004, p. 135) did not estimate a rangewide population for greater sagegrouse, but did state that the number is probably much greater than the estimate by Braun (1998).
Although Connelly et al. (2004) were unable to estimate rangewide population numbers for greater sagegrouse, they did use lek count data as an indication of population changes since 1965 (Connelly et al. 2004, Chapter 6). They reported substantial declines from 1965 through 2003 with an average decline of 2 percent of the population per year during this time period (Connelly et al. 2004, p. 671). The decline was more pronounced from 1965 through 1985, with an average annual change of 3.5 percent (Connelly et al. 2004, p. 671). However, the rate of decline rangewide slowed from 1986 to 2003 to 0.37 percent annually (Connelly et al. 2004, p. 671).
The best available scientific and commercial information regarding the past, present, and future threats faced by the greater sagegrouse were reviewed by the Service, including information on population declines. Based on that review, on January 12, 2005, the Service published a finding that listing the greater sagegrouse was not warranted (70 FR 2243). The Service noted that although sagebrush habitat and sagegrouse populations had declined and were continuing to decline in some areas, the most recent data indicated overall population declines had slowed, stabilized, or populations had increased, and that the threats, when considered in relation to the status, trend, and distribution of the current population, were not sufficient to result in the greater sagegrouse becoming an endangered species in the foreseeable future (Federal Register, January 12, 2005, pp. 22802281).
Mono Basin Area Sage Grouse
The States of California and Nevada jointly supported development of a conservation plan, entitled Greater Sage Grouse Conservation Plan for Nevada and Eastern California (SageGrouse Conservation Team 2004). A draft version of the Greater Sage Grouse Conservation Plan for Nevada and Eastern California was submitted to a sevenperson team for external science peer review (SageGrouse Conservation Team 2004, p. 6). The conservation plan written specifically for sagegrouse in the Mono Basin area is the Greater SageGrouse Conservation Plan for the BiState Plan Area of Nevada and Eastern California (BiState Plan) (BiState Local Planning Group 2004), and is an appendix of the Greater SageGrouse Conservation Plan for Nevada and Eastern California. The 2005 petition frequently refers to the BiState Plan. The BiState Plan was not peer reviewed. The group that developed the BiState Plan consisted of local biologists, land managers, land users, and others with concerns about sagegrouse in western Nevada and eastern California (BiState Plan 2004, p. vi).
The BiState Plan covers the same geographic area described in the 2001 and 2005 petitions as the Mono Basin area, but refers to it as the BiState area (BiState Local Planning Group 2004, pp. 45). The Mono Basin area includes portions of Alpine and Inyo Counties, and most of Mono County in California and portions of Lyon, Douglas, Carson City, Esmeralda, and Mineral Counties in Nevada.
Sagegrouse in the Mono Basin area historically occurred approximately throughout Mono, eastern Alpine, and northern Inyo Counties, California (Hall 1995, Figure 1); and parts of Carson City, Esmeralda, Mineral, Lyon, and Douglas Counties, Nevada. The current range of the population in California is reduced from the historic range (Leach and Hensley, 1954, p. 386; Hall 1995, p. 54). Gullion and Christensen (1957, pp. 131132) documented that sagegrouse occurred throughout most of their historic range in Nevada, including occurrences in Esmeralda, Mineral, Lyon, and Douglas Counties, but not in Carson City County, although Espinosa (2006) hypothesized that birds may still persist in this County. Sagegrouse habitat has been lost in the Nevada portion of the BiState area but the extent of the loss has not been estimated (Stiver 2002).
Prior to development of the Greater Sage Grouse Conservation Plan for Nevada and Eastern California, the State of Nevada sponsored development of the Nevada SageGrouse Conservation Strategy (Sage Grouse Conservation Planning Team 2001). This Strategy established Population Management Units (PMUs) for Nevada and California as management tools for defining and monitoring sagegrouse distribution (SageGrouse Conservation Planning Team 2001, p. 31). The PMU boundaries are based on aggregations of leks, sagegrouse seasonal habitats, and existing sagegrouse telemetry data (SageGrouse Conservation Planning Team 2001, p. 31). PMUs that comprise the Mono Basin area include the Pine Nut, Desert CreekFales, Mount Grant, Bodie, South Mono, and White Mountains PMUs. The BiState Plan (2004) is the only existing assessment of greater sagegrouse populations and habitats specific to the PMUs that comprise the Mono Basin area.
Currently in the Mono Basin area, sagegrouse leks occur in the Pine Nut, Desert CreekFales, Bodie, Mount Grant, South Mono, and White Mountains PMUs (BiState Plan 2004). Most of the leks occur in the Bodie and South Mono PMUs (BiState Plan 2004). Of the 122 known lek locations in the Mono Basin area: 56 are on Bureau of Land Management (BLM) land, 30 are on U.S. Forest Service (USFS) land, 4 are on Department of Defense land, 2 are on State of California land, 9 are on Los Angeles Department of Water and Power land, and 21 occur on private land (Espinosa 2006; Taylor 2006). Overall, 83 percent of the leks are on public land and 17 percent occur on private land. Based upon the extent of previous survey work, it is unlikely that more leks will be found in the Nevada portions of the Pine Nut and Desert CreekFales PMUs (Espinosa 2006). Due to longterm and extensive survey efforts, it also is unlikely that new leks will be found in the California portion of the Pine Nut and Desert CreekFales PMUs or the Bodie and South Mono PMUs (Gardner 2006). However, it is possible that more leks will be discovered in the Mount Grant PMU and the Nevada portion of the White Mountains PMU because these are less accessible and there has been less survey effort in them (Espinosa 2006). More leks also may be discovered in the California portion of the White Mountains PMU, which is difficult to access and has not been well surveyed (Gardner 2006).
Sagegrouse population trends analyzed for California and Nevada for 19652003 (Connelly et al. 2004, pp. 6
[[Page 76061]]
24 to 626 and 636 to 639) led to a conclusion that populations in
California had slightly increased over this timeframe while those in
Nevada had declined (Connelly et al. 2004, pp. 667 to 668). However,
this analysis was performed at the State level and did not specifically analyze population trends for the Mono Basin area.
The BiState Plan (2004) provides some information on population trends for some of the PMUs in the Mono Basin area, and indicates that in some areas population declines occurred historically. However, the number of leks surveyed, survey methodology, and techniques for estimating population size are inconsistent and have varied considerably over time, making it very difficult to interpret or rely on the information. In 2003, the NDOW began estimating population numbers based on a peer reviewed and accepted formula (NDOW, 2006, p. 1), and consequently we believe the most accurate population estimates for the Nevada portion of the Mono Basin area start in 2003. Prior to that, Nevada survey efforts varied from year to year, with no data for some years, and inconsistent survey methodology. Although CDFG methods for estimating populations of sagegrouse have been more consistent prior to 2003, using population estimates for sagegrouse derived before 2003 would lead to invalid and unjustified conclusions given the variation in the number of leks surveyed, survey methodology, and population estimation techniques between NDOW and CDFG. Due to past differences in consistency in population estimation techniques for the two States, in this description of populations we are only presenting population numbers from 20032006. During this period of time, both states used the same population estimation methods. We provide this information to help inform the public, and for the reasons described above, we did not consider this information in our Threats Analysis (below) and it was not part of the basis for making this finding.
CDFG and NDOW annually coordinate sagegrouse lek counts in the California and Nevada portions, respectively, of the Mono Basin area. Results from these lek counts are used by CDFG and NDOW to estimate sagegrouse populations for PMUs in the Mono Basin area. CDFG and NDOW calculate low and high sagegrouse population estimates for the PMUs, based on low and high lek detection rates, respectively, to account for the range in lek detection rates.
The following spring population estimates are based on lek counts for the South Mono, Bodie, Mount Grant, and Desert CreekFales PMUs (CDFG 2006; NDOW 2006). They also include population estimates from the Nevada portion of the Pine Nut PMU (NDOW 2006). However, they do not include population estimates for the White Mountains PMU or the California portion of the Pine Nut PMU (CDFG 2006; NDOW 2006). The White Mountain PMU and the California portion of the Pine Nut PMU together comprise about 41 percent of the Mono Basin area. Due to the lack of information on sagegrouse habitat for the Mono Basin, we cannot state what percent of the current habitat occurs in these two areas for which population estimates are unavailable. The recent spring population estimates for the areas described above are as follows: 2003a low estimate of 2820 birds and a high estimate of 3181 birds, 2004a low estimate of 3682 birds and a high estimate of 4141 birds, 2005a low estimate of 3496 birds and a high estimate of 3926 birds, and 2006a low estimate of 4218 birds and a high estimate of 4740 birds (CDFG 2006; NDOW 2006). Spring populations largely reflect the number of breeding sagegrouse in this area. The number of breeding sagegrouse is representative of effective population size and probably one of the best ways to assess the health of the overall population.
At a minimum, the spring population estimates for sagegrouse in the Mono Basin area indicate that the surveyed populations have not declined in recent years. Indeed, 2004 to 2006 spring lek counts for the Long Valley lek complex, which comprises most of the leks in the South Mono PMU, are the highest numbers counted in the last 30 years and sagegrouse in this area are more productive than anywhere else in California (Gardner 2006).
Casazza et al. (2006) conducted a 3year study on sagegrouse in the Mono Basin area to determine movements. The researchers radio marked birds in Mono County within the Desert CreekFales, Bodie, White Mountains, and South Mono PMUs (Casazza et al. 2006, unpaginated). The greatest distances moved by radiotagged birds between two points is as follows: About 29 percent moved 08 km (05 mi); about 41 percent moved 816 km (510 mi); about 25 percent moved 1624 km (1015 mi); about 4 percent moved 2432 km (1520 mi); and about 1 percent moved a distance greater than 32 km (20 mi) (Overton 2006). Female sagegrouse home range size ranged from 2.3 to 137.1 sq km (0.9 to 52.9 sq mi), with a mean home range size of 38.6 sq km (14.9 sq mi) (Overton 2006). Male sagegrouse home ranges ranged in size from 6.1 to 245.7 sq km (2.3 to 94.9 sq mi), with a mean home range size of 62.9 sq km (24.1 sq mi) (Overton 2006).
Distinct Population Segment
We consider a species for listing under the Act if available information indicates such an action might be warranted. ``Species'' is defined by the Act as including any species or subspecies of fish and wildlife or plants, and any distinct vertebrate population segment of fish or wildlife that interbreeds when mature (16 U.S.C. 1532 (16)). We, along with the National Marine Fisheries Service (now the National Oceanic and Atmospheric AdministrationFisheries), developed the Policy Regarding the Recognition of Distinct Vertebrate Population Segments (DPS Policy) (February 7, 1996, 61 FR 4722) to help us in determining what constitutes a DPS. The policy identifies three elements that are to be considered in a decision regarding the status of a possible DPS. These elements include (1) the discreteness of a population in relation to the remainder of the species to which it belongs; (2) the significance of the population segment to the species to which it belongs; and (3) the population segment's conservation status in relation to the Act's standards for listing. Our policy further recognizes it may be appropriate to assign different classifications (i.e., threatened or endangered) to different DPSs of the same vertebrate taxon (February 7, 1996, 61 FR 4722).
Discreteness
The November 2005 and December 2001 petitions assert that Mono
Basin area sagegrouse qualify as a Distinct Population Segment (DPS)
based on discreteness. Both petitions cite the Services' DPS policy
under the Act (February 7, 1996, 61 FR 4722) and both assert that Mono
Basin area sagegrouse are discrete based on genetic distinctiveness.
The DPS policy states that a population segment may be considered
discrete if it satisfies either one of the following conditions: (1) It
is markedly separated from other populations of the same taxon as a
consequence of physical, physiological, ecological, or behavioral
factors. Quantitative measures of genetic or morphological
discontinuity may provide evidence of this separation. (2) It is
delimited by international governmental boundaries within which
differences in control of exploitation, management of habitat,
conservation status or regulatory mechanisms exist that are significant
in light of section 4(a)(1)(D) of the Act. In a previous 90 [[Page 76062]]
day finding, we reviewed the December 2001 petitioners' claim that Mono
Basin area sagegrouse are a DPS, and found that there was not
substantial scientific or commercial information indicating that Mono
Basin area sagegrouse may be discrete from other greater sagegrouse
(December 26, 2002, Federal Register, p. 78811). Our 2002 determination
was based on a lack of information to demonstrate that Mono Basin sage
grouse are physically isolated from other nearby populations, the
limited extent of sagegrouse genetic sampling within the Mono Basin
area at that time, information from a comparative study which indicated
that Mono Basin sagegrouse are not behaviorally different from other
populations of great sagegrouse, and the lack of any morphological information on Mono Basin sagegrouse.
We still believe that there are no significant behavioral differences between sagegrouse populations. Young et al. (1994) compared greater sagegrouse behavioral attributes for populations in the Mono Basin area and outside it for males displaying on leks. This study concluded that sagegrouse in the Mono Basin area do not exhibit any appreciable behavioral differences in male mating displays from other greater sagegrouse populations (Young et al., 1994).
In contrast to results from comparative behavioral studies, comparative genetics studies have documented genetic differences between greater sagegrouse populations in the Mono Basin area and those outside of it. The November 2005 petition correctly cites Benedict et al. (2003), OylerMcCance et al. (2005), and the BiState Plan (2004) with regard to how sagegrouse in the Mono Basin area are genetically unique from other populations of greater sagegrouse. Since we published our previous 90day finding, comparisons of genetic material from many sagegrouse populations across the range of the species have been completed and demonstrate that Mono Basin area sage grouse contain unique haplotypes not found elsewhere within the range of the greater sagegrouse (Benedict et al. 2003; OylerMcCance et al. 2005). Genetic sampling continues in the Mono Basin area, as the full geographic extent of this genetic uniqueness has not yet been determined. However since our previous 90day finding on Mono Basin area sagegrouse (December 26, 2002, 67 FR 78811), most leks in the Mono Basin area have now been genetically sampled. Although the full extent of this genetic uniqueness is undetermined, there now exists sufficient evidence to suggest that Mono Basin area sagegrouse are genetically distinct from other greater sagegrouse populations (Benedict et al. 2003; OylerMcCance et al. 2005). The November 2005 petitioners assert that genetic work by Benedict et al. (2003) or OylerMcCance et al. (2005) support their contention that Mono Basin area sagegrouse area are presently isolated from other sagegrouse populations by present day habitat conditions, but this claim is inaccurate. These genetic studies provided evidence that the present genetic uniqueness exhibited by Mono Basin area sagegrouse occurred over thousands and perhaps tens of thousands of years (Benedict et al. 2003, p. 308; OylerMcCance et al. 2005, p. 1307). Hence, the genetic uniqueness of this sagegrouse population developed prior to the Euro American settlement in the Mono Basin area that resulted in changes in habitat conditions for this population.
The Services' DPS policy requires that only one of the discreteness criteria be satisfied in order for a population segment of a vertebrate species to be discrete. There is substantial information indicating that Mono Basin area sagegrouse are genetically distinct from other greater sagegrouse populations. Therefore, we conclude that there is substantial information indicating that the Mono Basin area sagegrouse may satisfy the discreteness criterion of the DPS policy.
Significance
Both the December 2001 petition and the November 2005 petition also assert that Mono Basin area sagegrouse further qualify as a DPS based on significance. The DPS policy (February 7, 1996, Federal Register, p. 4725) states that if a population segment is considered discrete under one or more of the discreteness criteria then its biological and ecological significance will be considered in light of Congressional guidance that the authority to list DPSs be used ``* * * sparingly'' while encouraging the conservation of genetic diversity. In such an examination, the Service considers available scientific evidence of the discrete population segment's importance to the taxon to which it belongs. As specified in the DPS policy February 7, 1996, Federal Register, p. 4725), this consideration of the significance may include, but is not limited to, the following: (1) Persistence of the discrete population segment in an ecological setting unusual or unique to the taxon; (2) Evidence that loss of the discrete population segment would result in a significant gap in the range of a taxon; (3) Evidence that the discrete population segment represents the only surviving natural occurrence of a taxon that may be more abundant elsewhere as an introduced population outside its historic range; or (4) Evidence that the discrete population segment differs markedly from other populations of the species in its genetic characteristics.
The November 2005 petition claims that the Mono Basin area is a unique ecological setting and cites a map in Rowland et al. (2003) to support this claim. This petition also asserts that the loss of the Mono Basin area population would result in a significant gap in the range of the greater sagegrouse and that the population differs markedly from other sagegrouse populations in genetic characteristics.
The Mono Basin area sagegrouse populations do occur in an
ecological province labeled the Mono province in Rowland et al. (2003,
p. 63). However, this ecological province is part of the Great Basin,
and on a gross scale all the ecological provinces that comprise this
area are characterized by basin and range topography. Basin and range
topography covers a large portion of the western United States and
northern Mexico. It is typified by a series of northsouth oriented
mountain ranges running parallel to each other, with arid valleys
between the mountains. Most of Nevada and eastern California are
covered by basin and range topography. Hence, we do not concur that
Mono Basin area sagegrouse occur in an ecological setting that is
unique for the taxon. Based on the extant range of greater sagegrouse
provided by Schroeder et al. (2004, p. 369), we do not agree that the
loss of the Mono Basin area sagegrouse population would result in a
significant gap in the range of greater sagegrouse. Schroeder et al.
(2004, p. 363) estimated total extant range of greater sagegrouse to
be 668,412 sq km (258,075 sq mi) and the total area of the PMUs that
comprise the Mono Basin area is 18,310 sq km (7,069 mi) (BiState Plan
2004). Hence, the total area comprised by the Mono Basin represents at
most about 3 percent of the total extant range of greater sagegrouse
and loss of the population in this area would not result in a
significant gap in the range of the species. Mono Basin area sage
grouse are not the only surviving occurrence of the taxon, and as
previously discussed represent a small proportion of the total extant
range of the species. However, existing genetic evidence (Benedict et
al. 2003; OylerMcCance et al. 2005) does indicate that Mono Basin area
sagegrouse differ from other populations of greater sagegrouse in their genetic
[[Page 76063]]
characteristics, as discussed previously with regard to the
discreteness criterion. Therefore, based on information regarding
genetics, we conclude that there is substantial information indicating
that the Mono Basin area sagegrouse may satisfy the significance criterion of the DPS policy.
DPS Conclusion
We have reviewed the information presented in the petitions, and have evaluated the information in accordance with 50 CFR 424.14(b). In a 90day finding, the question is whether a petition presents substantial information that the petitioned action may be warranted. We do not make final determinations regarding DPSs at this stage; rather, we determine whether a petition presents substantial information that a population may be a DPS. On the basis of our review, we find that the November 2005 petition, and our files, do present substantial scientific or commercial information to indicate that Mono Basin area sagegrouse may be a DPS based, on genetic evidence, which may meet both the discreteness and significance criteria of the DPS policy. Based on this preliminary assessment, we proceeded with an evaluation of information presented in both petitions, as well as information in our files, to determine whether there is substantial scientific or commercial information indicating that listing this population may be warranted. Our threats analysis and conclusion follow.
Threats Analysis
Section 4 of the Act and its implementing regulations (50 CFR part 424) set forth the procedures for adding species to the Federal List of Endangered and Threatened Wildlife and Plants. A species may be determined to be an endangered or threatened species due to one or more of the five factors described in section 4(a)(1) of the Act: (A) Present or threatened destruction, modification, or curtailment of habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation; (D) inadequacy of existing regulatory mechanisms; or (E) other natural or manmade factors affecting its continued existence. In making this 90 day finding, we evaluated whether information on threats to the Mono Basin area sagegrouse in our files and presented in the November 2005 and the December 2001 petitions constitutes substantial scientific or commercial information such that listing under the Act may be warranted. Our evaluation of this information is presented below. A. Present or Threatened Destruction, Modification, or Curtailment of the Species' Habitat or Range
Geographic Range
The November 2005 petition asserts that the range of sagegrouse in the Mono Basin area is greatly reduced and that the populations are scattered among several counties in western Nevada and eastern California. Petitioners cite the work of Schroeder et al. (2004) and claim that in presettlement time the habitat for the species was continuous along the CaliforniaNevada border and extended from Inyo County, California, into Oregon. The petition further states that by 2000 the Mono Basin area population had become physically isolated from other sagegrouse populations and now only occurs in small isolated groups. The petitioners cite a Western States Sage Grouse Technical Committee report (WSSGTC 1999) and state that for the Nevada portion of the Mono Basin area sagegrouse are extirpated from Storey and Carson City Counties, at extreme risk in Douglas and Esmeralda Counties, and at risk in Lyon and Mineral Counties. Regarding sagegrouse range in California, the petition cites Hall (1995) and states that there has been a 55 percent reduction statewide in the range of the species from its historic range. More specific to the Mono Basin area, the petitioners cite our December 26, 2002, 90day finding (67 FR 78811), which states that suitable habitat for the California portion of the Mono Basin area has declined approximately 71 percent from historic levels based on information in Hall (1995). The petitioners also cited OylerMcCance et al. (2001) to state that extirpations of local populations of Gunnison sagegrouse have occurred because of the loss and fragmentation of habitat caused by human activities; cited Barbour (1988, unpaginated) regarding impacts to sagebrush habitat in California; and cited Braun's (1998, unpaginated) assessment of factors that have caused sagegrouse declines across the western United States, which included habitat loss.
We agree with the petitioners that there has been a reduction in the distribution of greater sagegrouse along the CaliforniaNevada border (Schroeder et al. 2004, pp. 368369). Distribution in the Mono Basin area is much more disjunct now compared to presettlement conditions; however, the southern limit of sagegrouse distribution along the CaliforniaNevada border has not changed (Schroeder et al. 2004, pp. 368369). A considerable amount (approximately 71 percent) of the original sagegrouse habitat has been lost in the California portion of the Mono Basin area (Hall, 1995, p. 54; December 26, 2002, Federal Register, p. 78813). The extent of habitat has also declined within the Nevada portion of the Mono Basin area, but no estimates are provided in the petitions or available in our files regarding the Nevada portion. The BiState Plan (2004) provides limited anecdotal information about the historic range of the population in the Mono Basin area, and the distribution and range discussion is focused primarily on current conditions. Additionally the work cited from OylerMcCance et al. (2001) and Braun (1998) is not specific to the Mono Basin area. Connelly et al. (2004) did assess changes for the sagebrush ecosystem, but this analysis was also performed at the rangewide level for sagegrouse and not specific to the Mono Basin area. Although sagegrouse habitat and range has been reduced from pre settlement conditions, and some additional habitat losses may be occurring at present, neither the petitioners, nor our files, provide information on the rate or extent of habitat losses for the Mono Basin area. The BiState Plan (2004) documents some loss of specific localized habitat areas due to wildfire. The Service recognizes that historically there has been destruction and modification of the habitat and range of sagegrouse in the Mono Basin area. However, historic impacts are not the focus of the evaluation called for under Factor A; rather, Factor A specifically addresses the present or threatened destruction, modification, or curtailment of habitat or range. Although the petitioners and our files contain information on historic reductions in range, neither the petitioners, nor our files, provide substantial information that documents the present or threatened loss of sagegrouse range for sagegrouse in the Mono Basin area. Therefore, we conclude that there is not substantial scientific or commercial information to indicate that listing may be warranted due to the present or threatened destruction or modification of habitat or range for the sagegrouse population in the Mono Basin area.
Private Land Development
The November 2005 petition cites private land development as a
significant threat to Mono Basin area sagegrouse. The petitioners
state that over 329,000 acres (close to 12 percent) of land in the Mono Basin area is
[[Page 76064]]
privately owned and susceptible to development. They cite the BiState
Plan (2004) regarding private land development in several of the PMUs
and reference discussions of: community expansion in the Pine Nut PMU;
conversion of private rangeland to residential and vacation homes,
conversion of grouse winter habitat to irrigated pasture and hay
fields, and increased pressure of subdivision and development in the
Desert CreekFales PMU; increasing development of private lands for
residential, commercial and recreational purposes in the Bodie PMU; and
development of private lands in the South Mono PMU. The petitioners
claim that Mono County intends to significantly expand the Benton
Crossing Landfill, which could impact sagegrouse through direct
habitat loss, increased predation, and a potential increase in disease
(Mono County 2004). They also cite a process to revise the Mammoth
Lakes general plan (Mammoth Lakes 2005) and claim the revised plan will
allow for more development on nonFederal lands. The petitioners assert
that expansion of the Mammoth Lakes airport to accommodate commercial
jets and construction of an adjacent business park would pose a
significant impact to sagegrouse in the South Mono PMU. Petitioners
cite a California Department of Fish and Game memo (California
Department of Fish and Game 2001) and state that the California
Department of Fish and Game expressed serious concerns about the
impacts of the proposed airport expansion on sagegrouse. The
petitioners claim that California Department of Fish and Game expressed
several concerns, including that aircraft may disturb birds on leks and
while they are wintering and that the airport expansion project would
have growthinducing impacts to the region. Finally, they claim that a
number of other proposed developments could affect the South Mono sage grouse population.
The December 2001 petition also cited development and habitat conversion to suburbs and ranchettes as a threat to sagegrouse. However, this petition did not provide additional information beyond what was provided in the November 2005 petition.
The November 2005 petition is incorrect in asserting that close to 12 percent of the Mono Basin area is privately owned. Their figures do not include the White Mountains PMU, which comprises about 38 percent of the total area; including this PMU, approximately 8 percent of lands within the Mono Basin area are privately owned (BiState Plan 2004). Connelly et al. (2004, pp. 725, 726) included some analysis of the effects of development (including associated infrastructure) on sage grouse, but the analysis was conducted at the rangewide scale (Connelly et al. 2004, pp. 121 to 1223) and not specific to the Mono Basin area. The BiState Plan (2004) recognizes urban expansion as a risk to sagegrouse in the Pine Nut PMU (BiState Plan 2004, p. 24), the Desert CreekFales PMU (BiState Plan 2004, p. 47), the Bodie PMU (BiState Plan 2004, p. 88), and the South Mono PMU (BiState Plan 2004, p. 169).
Although development of private lands may impact sagegrouse habitat (Connelly et al. 2004) and there are concerns about private lands being developed for housing in the Mono Basin area (BiState Plan 2004, p. 4), about 89 percent of the land area within the Mono Basin area is federally managed land, primarily USFS and BLM lands (BiState Plan 2004). These public lands are not the areas where traditional development into housing communities is occurring and are not subject to such development. Furthermore, although some housing development has occurred on private lands within the Mono Basin area, the five housing subdivisions cited by the petitioners are considered speculative, as they have not moved beyond the planning stage. The petitioners are correct that the Town of Mammoth Lakes General Plan is being updated and does allow for more housing development on private land; however, the petitioners fail to note that this growth is planned to occur within the Mammoth Lakes Urban Growth Boundary (Town of Mammoth Lakes 2005, pp. 39 to 314), well away from known lek sites, and therefore it will not directly impact sagegrouse. Additionally, the Benton Crossing Landfill will not be expanded as the petition asserts (Town of Mammoth Lakes 2005, p. 238).
The Federal Aviation Administration (FAA) has dropped its proposal to expand the Mammoth Yosemite Airport (FAA 2006). However, the FAA is currently proposing to resume regional commercial air service using the existing Mammoth Yosemite Airport facilities, with two winter flights per day initially and potentially increasing to a maximum of eight winter flights per day by 20122013 (FAA 2006). The Mammoth Yosemite Airport had regional commercial air service from 1970 to the mid1990s (FAA 2006) and it currently supports about 400 flights per month, primarily singleengine aircraft (Town of Mammoth Lakes 2005, p. 4 204). Therefore, sagegrouse in the South Mono PMU that occur in lek areas in the near proximity of the Mammoth Yosemite Airport have been exposed to commercial air traffic in the past, and they are presently exposed to private air traffic. Effects of the FAA proposal to reinstate commercial air traffic at the Mammoth Yosemite Airport on sagegrouse are unknown at this time, as the level of commercial flight traffic these birds may be exposed to is undetermined and subject to commercial success by the airlines. Also, since the proposal by FAA has yet to be implemented, any assessment of effects is speculative. The FAA will develop an environmental analysis for the proposed project pursuant to the National Environmental Policy Act (NEPA) (FAA 2006), which will include an assessment of impacts to wildlife. The Town of Mammoth Lakes is proposing commercial development on a tract of land immediately adjacent to the existing airport (Town of Mammoth Lakes 2005, p. 29). We do not have information in our files to determine whether the area of proposed development involves sagegrouse habitat.
In summary, development of private lands for housing and the associated construction of roads and power lines within the Mono Basin area would occur mostly in areas where sagegrouse are not present. Furthermore, petitioners' claims about expansion of the Mammoth Yosemite Airport are no longer valid, and they did not provide information which documents how the proposed resumption of commercial air service at the Airport, combined with the construction of an adjacent business park, would impact sagegrouse in the South Mono PMU. Most significantly, about 89 percent of the Mono Basin area is federally managed land (BiState Plan 2004), where development into housing communities is not occurring. Neither the petitioners, nor our files, provide information on the extent or magnitude of private development to indicate that listing of the Mono Basin area sagegrouse may be warranted due to the present or threatened destruction, modification, or curtailment of sagegrouse habitat or range due to private land development.
Public Land Development
The November 2005 petition states that the majority of the Mono
Basin area sagegrouse habitat is managed by BLM and the USFS under
multipleuse policies that have harmed sagegrouse and degraded their
habitat. Petitioners assert that public land is subject to some forms
of development and that private land development often affects the [[Page 76065]]
integrity and health of adjacent public lands. The petitioners cite the
BiState Plan (2004) with regard to the Bodie PMU and state that
habitat loss and fragmentation associated with land use change and
development is not restricted to private lands in this PMU. Petitioners
further assert that development of private lands can also have indirect
effects on sagegrouse populations and habitat on public lands. They
cite the BiState Plan (2004) for the Desert CreekFales PMU and note
that residential development may reduce habitat, resulting in risks to
habitat quality and fragmentation. The petitioners indicate that the
BiState Plan provides no new regulatory measures or funding for
mitigation of threats from private land use and development.
The petitioners cite the BiState Plan (2004) to support their claim that 13 sites have been authorized for monitoring for wind energy development in the Pine Nut PMU and wind turbines may be constructed on these sites. The petitioners also state that numerous geothermal energy developments have been proposed or approved on public and private land in the South Mono PMU (BiState Plan 2004) and specifically reference a proposal for the Inyo National Forest claiming that sagegrouse have been found within 0.4 km (0.25 mi) of the proposed project and that the project may displace individual sagegrouse by eliminating suitable habitat for the species (USFS 2005).
The petition claims that a myriad of other smaller projects or activities are authorized and developed on Federal lands. In support of this assertion, the petitioners indicate that records they obtained from the BLMCarson City Field Office for these smaller projects and lesser activities authorized between 2001 and 2005 included 55 records of categorical exclusions and 13 findings of no significant impact under the National Environmental Policy Act (NEPA). The petitioners further stated that these decisions were for a variety of projects, including rightsofway, road construction, communication towers, power lines, gas/water/sewer pipelines, water tanks, fiber optic/telephone cables, seismometer stations, irrigation facilities, monitoring wells, and a railroad. The petition asserts that, although the size and scope of these are considered minor by Federal management agencies, and hence their potential environmental impacts are not assessed under NEPA, their cumulative impact fragments and degrades sagebrush habitat in the Mono Basin area.
As noted previously, the majority of the land area in the Mono Basin area, and therefore most of the sagegrouse habitat, is managed by BLM and the USFS; approximately 89 percent of the land in the Mono Basin area is administered by these agencies (BiState Plan 2004). Both of these Federal agencies manage public lands on a multipleuse basis under Federal laws (January 12, 2005, Federal Register, pp. 2272, 2274). The multipleuse management approach allows for a wide array of actions on Federal lands, including some forms of development that may be detrimental, as well as conservation measures that are beneficial, for habitat of wildlife species such as sagegrouse. When private lands adjacent to public lands are developed, there can be impacts to sage grouse on the public lands (Braun 1998, unpaginated) and Connelly et al. (2004, pp. 724 to 726), both document impacts to sagegrouse as a result of urbanization, such as loss of habitat.
Several urban and suburban areas in this PMU are continuing to
expand in the Pine Nut PMU (BiState Plan 2004, p. 24). For the Bodie PMU, the BiState Plan does indicate that habitat loss and
fragmentation associated with land use change and development is not
restricted to private lands (BiState Plan 2004, p. 88). Rightsofways
across public lands for roads, utility lines, sewage treatment plants
and other public purposes are frequently requested, and granted, to
support development activities on adjacent private lands (BiState Plan
2004, p. 88). But the BiState Plan concludes that land use and
development on most lands in the Bodie PMU are guided by existing land
use plans and that the development is a manageable risk for sagegrouse
(BiState Plan 2004, p. 88). Residential development was reported to be
very low in the White Mountains PMU (BiState Plan 2004, p. 124).
Effects of public land development were not cited among the risk
factors described for the Mount Grant PMU (BiState Plan 2004).
We have also evaluated the threat of energy development as presented by the petitioners. According to the BiState Plan (2004, p. 31) three sites in the Pine Nut PMU have been authorized for monitoring wind energy potential, not 13 sites as presented by the petitioners. The BiState Plan expresses concern about possible threats arising from infrastructure, such as roads and power lines, associated with wind energy development in this area (BiState Plan 2004, p. 31). Connelly et al. (2004, p. 743) discuss wind energy development as a factor that could impact sagebrush ecosystems. There is also potential for wind energy and geothermal energy development in the South Mono PMU (Bi State Plan 2004, p. 178). The South Mono PMU has an existing geothermal plant and the BiState Plan discusses four other proposed geothermal energy projects in the PMU, only one of which has been approved (Bi State Plan 2004, pp. 178181). The BiState Plan indicates that geothermal development in the South Mono PMU is a manageable risk, and that the USFS and BLM both have management plans in place that consider effects of this activity on sagegrouse (BiState Plan 2004, p. 181). One of the geothermal projects discussed in the BiState Plan is being evaluated by the USFS (Inyo National Forest 2005). The project would occur in suitable habitat for sagegrouse, and birds have been documented within 0.4 km (0.25 mi) of the site (Inyo National Forest, 2005, p. 7). However, the USFS evaluation concluded that while the proposed geothermal project may affect individuals it would not likely result in a loss of sagegrouse viability because: the area was surveyed for leks and none were found; only about 3 acres of habitat would be lost; prior to construction, an area adjacent to the construction corridor would be surveyed for nests and if nests are located, construction would not be allowed within 30 meters (100 feet) until after the young had fledged (Inyo National Forest 2005, p. 22).
We acknowledge that development of public lands for a variety of purposes (including rightsofways for roads, power lines, utility lines, and wind and geothermal energy development) may impact some sagegrouse habitat. However, neither the petitioners, nor our files, provide information on the present or future extent or magnitude of public development as a threat for the Mono Basin area. Therefore, we conclude that there is not substantial scientific or commercial information to indicate that listing of the Mono Basin area sagegrouse may be warranted as a result of the present or threatened destruction, modification, or curtailment of sagegrouse habitat or range due to public land development.
Fences, Power Lines, Roads
The November 2005 petition cites Braun (1998) in stating that
fences and power lines fragment sagegrouse habitat, cause direct
mortality, and provide perches for avian predators. The petition cites
a Sierra Pacific Power Company report (Sierra Pacific Power Company
2003) and states that construction of transmission lines can [[Page 76066]]
increase weed invasion in sagebrush. The petitioners also cite a
personal communication with F. Hall from the BiState Plan (2004) which
indicates that, in northern California, power lines had a negative
effect on lek attendance and strutting activity, and fewer radiomarked
birds were lost as distance from power lines increased. For the Pine
Nut PMU the petitioners cite the BiState Plan (2004) in stating that:
The North Pine Nut lek is bordered on two sides by power lines;
strutting grounds and nest sites are within the hunting territory of
ravens (Corvus corax) that nest on power lines; and more new power
lines have been requested in the area. The petitioners also cite a BLM
Environmental Assessment (BLMCarson City Field Office 2004) in stating
that BLM recently authorized construction of a power line in the Pine
Nut PMU and this area includes suitable sagegrouse habitat and is
within 5 miles of a lek. For the Desert CreekFales PMU, petitioners
cite the BiState Plan (2004) in stating that recent declines in this
PMU may be linked to power line construction in the last 10 years.
Petitioners cite the BiState Plan (2004) and state that in the Bodie
area, a number of power lines may be affecting sagegrouse, and in the
South Mono PMU, sagegrouse are currently impacted by power lines and more may be constructed due to energy development.
The November 2005 petition cites a BLMBishop Field Office document (BLMBishop Field Office undated), which indicates that mortalities increase and lek use decreases when fences or power lines are built nearby. Petitioners cite the BiState Plan (2004) in stating that fences in the Bodie area have been identified as a potentially significant threat and they also cite Fatooh et al. (undated), which reports that sagegrouse in the Bodie Hills area were displaced from one lek area by a fence.
Regarding roads as a threat to sagegrouse, the November 2005 petition cites OylerMcCance et al. (2001) in stating that roads are an important cause of fragmentation and degradation of Gunnison sage grouse habitat. Petitioners also cite the assessment by Wisdom et al. (2003) in asserting that human disturbances from roads and other activities can also exacerbate the spread of cheatgrass into sagebrush ecosystems, and that disturbances such as road construction and use, inappropriate grazing, energy development, mining, and recreational activities can cause cheatgrass expansion.
The December 2001 petition also cited fences, power lines, and roads as a threat to sagegrouse. However, this petition did not provide additional information beyond what was provided in the November 2005 petition.
The effects of fencing on sagegrouse include direct mortality through collisions, creation of predator (raptor) perch sites, the potential creation of a predator corridor along fences (particularly if a road is maintained next to the fence), incursion of exotic species along the fencing corridor, and habitat fragmentation (January 12, 2005, 70 FR 2257). Power lines can directly affect sagegrouse by posing a collision and electrocution hazard, and can have indirect effects by increasing predation, fragmenting habitat, and facilitating the invasion of exotic annual plants (January 12, 2005, 70 FR 2256). Impacts from roads to sagegrouse may include direct habitat loss, direct mortality, the creation of barriers to migration corridors or seasonal habitats, providing predator travel corridors, facilitation of the spread of invasive plant species, and other indirect influences such as noise (January 12, 2005, 70 FR 2257).
The BiState Plan (2004, p. 28) does state that in the Pine Nut PMU there are power lines bordering the North Pine Nut lek. However, it also indicates that these power lines are 3.24.8 km (23 mi) away from active strutting grounds (BiState Plan 2004, p. 28) so they do not occur in close proximity to the leks. The petitioners other assertions about the Pine Nut PMU are accurate. The BLMCarson City Field Office did recently authorize construction of a power line in the Pine Nut PMU as stated by petitioners (BLMCarson City Field Office 2004). However, sagegrouse habitat is not present along the power line route or in its vicinity (BLMCarson City Field Office 2004, p. 315) and the closest known leks to the line are more than 8 km (5 mi) away (BLMCarson City Field Office 2004, p. 320). For the Desert CreekFales PMU the Bi State plan concludes that power lines are one of several types of infrastructure that are a risk to sagegrouse which can impact habitat for the species (BiState Plan 2004, p. 54). It also states that recent declines in the Fales population in the Desert CreekFales PMU may be related to construction of power lines and other associated land use activities (BiState Plan 2004, p. 54). In the Bodie PMU, the BiState Plan (2004, p. 81) characterizes utility lines as a past, current, and future risk that affects multiple sites and multiple birds. Also, the Bodie PMU utility line discussion in the BiState Plan cites a personal communication with F. Hall indicating that in northern California these lines have a negative effect on lek attendance and strutting activity and that radiotagged sagegrouse lost to avian predation increased as the distance to utility lines decreased (BiState Plan 2004, p. 81). The BiState Plan (2004, pp. 8182) identifies several utility lines in the Bodie PMU that may be negatively affecting sagegrouse. Land use plans in Bodie PMU do not predict or plan for any additional major, multiline, or highvoltage utility lines in this PMU (BiState Plan 2004, p. 82). For the Mount Grant PMU, the BiState Plan (2004, p. 137) indicates that a power line fragments this PMU and that the line provides perches for raptors. In the South Mono PMU, transmission lines were considered to be a risk to sagegrouse on a yearlong basis (Bi State Plan 2004, p. 169). The BiState Plan also mentions three transmission lines that either are impacting sagegrouse or may potentially impact them, and that future geothermal development may result in expansion of transmission lines in the South Mono PMU (Bi State Plan 2004, p. 169). The BiState Plan (2004, p. 120) indicates that construction of new transmission lines may fragment occupied or potential sagegrouse habitat in the White Mountains PMU.
BLMBishop Field Office (undated) documented increased sagegrouse mortality and decreased use of leks when fences or power lines are built nearby although the source of this statement was a summary sheet of information put together for a presentation, not a published report or study. Fatooh et al. (undated) reported that sagegrouse were displaced from one lek a
FOR FURTHER INFORMATION CONTACT
Robert D. Williams, Field Supervisor, Nevada Fish and Wildlife Office (see ADDRESSES) or 7758616300 (voice), or 7758616301 (fax).