# Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) and Taxonomic Revision

> Briefs, arguments, decisions, and more.

URL: https://www.frixlaw.com/law-library/documents/fr%3AE8-16813

## Record

- **Collection:** Federal Register
- **Document type:** Rule
- **Published:** August 5, 2008
- **Citation:** 73 FR 45534

## Text

DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R8-ES-2008-0014; 92210-1117-0000-B4]
RIN 1018-AV05
Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) and Taxonomic Revision

AGENCY:

Fish and Wildlife Service, Interior.

ACTION:

Final rule.

SUMMARY:

We, the U.S. Fish and Wildlife Service (Service), are designating critical habitat for the Sierra Nevada bighorn sheep (
Ovis canadensis sierrae
) under the Endangered Species Act of 1973, as amended (Act). In total, approximately 417,577 acres (ac) (168,992 hectares (ha)) fall within the boundaries of the critical habitat designation. The critical habitat is located in Tuolumne, Mono, Fresno, Inyo, and Tulare Counties, California. We also are finalizing the revision of taxonomy of the listed entity from a distinct population segment (DPS) of California bighorn sheep (
Ovis canadensis californiana
) to subspecies,
Ovis canadensis sierrae
, based on recent published information.

DATES:

This rule becomes effective on September 4, 2008.

ADDRESSES:

The final rule, economic analysis, and maps are available at
http://www.regulations.gov
and at
http://www.fws.gov/nevada
. Supporting documentation we used in the preparation of this final rule is available for public inspection, by appointment, during normal business hours, at the Nevada Fish and Wildlife Office, 1340 Financial Boulevard, Suite 234, Reno, NV 89523; telephone 775-861-6300; facsimile 775-861-6301.

FOR FURTHER INFORMATION CONTACT:

Robert D. Williams, U.S. Fish and Wildlife Service, Nevada Fish and Wildlife Office (see
ADDRESSES
section). If you use a telecommunications device for the deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

It is our intent to discuss only those topics directly relevant to the designation of critical habitat in this rule. For more information on the Sierra Nevada bighorn sheep, refer to the final listing rule published in the
Federal Register
on January 3, 2000 (65 FR 20) and the proposed critical habitat rule published in the
Federal Register
on July 25, 2007 (72 FR 40955).

The bighorn sheep (
Ovis canadensis
) is a large mammal in the family Bovidae described by Shaw in 1804 (Shackleton 1985, p. 1). Cowan (1940, pp. 519-569) recognized several subspecies based on geography and skull measurements. Recent genetic (Ramey 1993, pp. 62-86; 1995, p. 432-434; Boyce
et al.
1996, pp. 423-426, 429; Gutierrez-Espeleta
et al.
1998, pp. 7-9, 11) and morphological data (Wehausen and Ramey 1993, pp. 4-8; 2000, pp. 148-153), and review and reanalysis of Cowan's data (Ramey 1993, p. 83), do not support Cowan's original subspecies differentiations.

Ramey (1993, pp. 71-72; 1995, p. 432) found, based on mitochondrial DNA (mtDNA), bighorn sheep from the Sierra Nevada to be more allied with sheep occupying the adjacent desert area than those to the north. Ramey (1993, pp. 67-68; 1995, pp. 433, 435) also found Sierra Nevada bighorn sheep to be a distinctive group in the desert region extending east to Utah and New Mexico and south to northern Mexico. Ramey (1993 p. 54) used mtDNA as a genetic marker to help understand the evolutionary history of North American mountain sheep. From the 116 individuals included in the surveys, 16 different mtDNA haplotypes were identified in North America and four in Asia (Ramey 1993, p. 62). Two major mtDNA lineages of mountain sheep were indicated in North America (Ramey 1993, p. 63). Within the northern Alaska and western North America clade, three mtDNA lineages were identified (Ramey 1993, p. 72). One lineage included bighorn sheep in the desert ranges of the southwestern United States and Mexico and the Sierra Nevada (Ramey 1993, p. 72), where the Sierra Nevada population was found to be more closely related to the desert-dwelling sheep than those from the Cascade Ranges or Rocky Mountains (Ramey 1993, p. 72). Within the desert-dwelling sheep populations, Sierra Nevada bighorn sheep differed (Ramey 1993, p. 73). Ramey (1995 p. 429) used mtDNA as a genetic marker to help understand the evolutionary history of North American mountain sheep in the southwest United States. Ten mtDNA haplotypes were identified in the southwest, with a common one being found in most populations (Ramey 1995, pp. 431-432). The distribution of mtDNA variants in the southwest did not support the recognition of
O. c. cremnobates, O. c. mexicana
, and
O. c. nelsoni
as distinct and separate subspecies, but the mtDNA analysis did show a unique fixed haplotype for
O. c. californiana
from the Sierra Nevada (Ramey 1995, p. 433). Based on this finding, bighorn sheep from the Sierra Nevada could be distinguished from populations of other subspecies of bighorn sheep (Ramey 1995, p. 433). Results indicated that significant differences in mtDNA haplotype frequencies can be found among populations that are adjacent to one another and separated by short distances (Ramey 1995, p. 435). A few rare haplotypes were limited in distribution and found in only single populations. One of these populations included the Sierra Nevada (Ramey 1995, p. 433).

Wehausen and Ramey (2000, pp. 148-153) used univariate and multivariate statistical methods to examine the geographic variation in horn and skull characters of 694 bighorn sheep (
Ovis canadensis
) from the Great Basin to British Columbia and Alberta. California bighorn sheep (
O. c. californiana
) from Washington and British Columbia were not distinguishable from Rocky Mountain bighorn sheep (
O. c. canadensis
); however, they did differ from Sierra Nevada bighorn sheep populations considered to be
O. c. californiana
. Extirpated populations from northeastern California, Oregon, and southwestern Idaho shared a horn-related character with Nelson bighorn sheep (
O. c. nelsoni
) from the Great Basin; this shared character was different from Rocky Mountain bighorn sheep. Individuals from the Sierra Nevada were distinguishable from bighorn sheep from the Great Basin. These results agree with geographic patterns identified with the mtDNA studies of Ramey (1993, 1995) (Wehausen and Ramey 2000, p. 156). Wehausen and Ramey (2000, pp. 153-157) synonymized the extinct Audubon subspecies,
O. c. auduboni
, from east of the Rocky Mountains in eastern Montana and Wyoming, North Dakota, South Dakota, and western Nebraska with
O. c. canadensis
. They also assigned extinct and extant native populations of
O. c. californiana
from Washington and British Columbia to
O. c. canadensis
and the extinct native populations of
O. c. californiana
from northeastern California, northern Nevada, southwestern Idaho, and Oregon to
O. c. nelsoni
of the Great Basin desert form. Based on genetic and morphometric data, Wehausen and Ramey (2000, p. 156) concluded that bighorn sheep in the Sierra Nevada should be recognized as a separate subspecies of
O. canadensis
, but they

did not recommend a change in nomenclature at that time.

In a recent investigation of the taxonomy of Sierra Nevada bighorn sheep, Wehausen
et al.
(2005) reexamined the history of bighorn sheep nomenclature. Grinnell (1912, p. 144) recognized bighorn sheep from the Sierra Nevada of California as a distinct subspecies,
Ovis cervina
(=
canadensis
)
sierrae
, designating a 5-year-old ram as the type specimen. Cowan (1940, p. 556) did not recognize the subspecies O. c. sierrae as valid, but included animals from the Sierra Nevada as
O. c. californiana
. Wehausen and Ramey (2000, pp. 153-157) reassigned specimens from north of the central Sierra Nevada to
O. c. nelsoni
and
O. c. canadensis
. They kept the name
O. c. californiana
for bighorn sheep in central and southern Sierra Nevada (Wehausen and Ramey 2000, p. 156), raising the question of the correct subspecific name for animals inhabiting this area. Based on this investigation of the taxonomy of Sierra Nevada bighorn sheep and by the Principle of Typification (International Commission on Zoological Nomenclature 1999), cited in Wehausen
et al.
(2005, p. 217), Wehausen
et al.
(2005 p. 217) concluded, based on Grinnell's original type specimen, that the correct nomenclature for native sheep in the central and southern Sierra Nevada of California is
Ovis canadensis sierrae
(Grinnell). Therefore, with the publication of this final rule designating critical habitat for the Sierra Nevada bighorn sheep, we formally revise its taxonomy from DPS of California bighorn sheep (
Ovis canadensis californiana
) to subspecies
Ovis canadensis sierrae
.

Sierra Nevada bighorn sheep inhabit portions of the Sierra Nevada located along the eastern boundary of California in Tuolumne, Mono, Fresno, Inyo, and Tulare Counties. Habitat occurs from the eastern base of the range as low as 4,790 feet (ft) (1,460 meters (m)) to peaks above 14,100 ft (4,300 m) (Wehausen 1980, pp. 3, 82).

Based on recent modeling efforts, discussed further in the Criteria Used To Identify Critical Habitat section, Sierra Nevada bighorn sheep habitat, as well as areas necessary to provide connectivity between winter and summer ranges, occur as low as 4,000 ft (1,219 m) in the southern portion of its range (Johnson
et al.
2005). Sierra Nevada bighorn sheep inhabit open areas where the land is rocky, sparsely vegetated, and characterized by steep slopes and canyons (Wehausen 1980, p. 81; Sierra Nevada Bighorn Sheep Interagency Advisory Group 1997, p. 5). Wehausen (1980, pp. 18-25) provides a detailed description of Sierra Nevada bighorn sheep habitat throughout its range. They prefer open ground to better detect predators and allow enough time to reach steep, rocky terrain (escape habitat) (Wehausen 1980, p. 81). Forests and thick brush are usually avoided if possible (65 FR 21; January 3, 2000). Most of the sheep live at higher elevations (10,000-14,000 ft (3,050-4,270 m)) in subalpine and alpine areas during the summer (65 FR 21; January 3, 2000). During winter, these sheep occupy high-elevation, windswept ridges and tend to prefer south-facing slopes where snow melts more readily (Jones 1950, pp. 44-45; McCullough and Schneegas 1966, p. 71; Wehausen 1980, pp. 86-87) or migrate to lower elevations (4,800 ft (1,460 m)) in sagebrush-steppe areas to avoid deep snow and to find forage.

Sierra Nevada bighorn sheep are gregarious, with group size and composition depending on gender and season. Spatial segregation by gender occurs outside of the mating season. Bighorn sheep ewes generally remain with the same band in which they were born (Cowan and Geist 1971, pp. 80-81). Males older than 2 years of age remain apart from females and younger males for most of the year (Jones 1950, p. 50; Cowan and Geist 1971, p. 65; Wehausen 1980, p. 109). During the late fall and winter, the groups come together and concentrate in suitable winter habitat.

Breeding takes place in late fall, generally November and December (Jones 1950, pp. 63-64; Cowan and Geist 1971, p. 64; Wishart 1978, p. 165). Lambing occurs between late April and early July (Wehausen 1996, p. 475) on safe, precipitous, rocky slopes (Wehausen 1980, p. 95); most lambs in the Sierra Nevada are born in May and June (Wehausen 1980, p. 94; 1996, p. 475). Ewes and lambs often occupy steep terrain that provides a diversity of exposures and slopes for escape cover (65 FR 21; January 3, 2000). The lifespan for both Sierra Nevada bighorn sheep males and females has been observed as 8 to 12 years (Wehausen 1980, p. 76; Stephenson 2008, p. 1).

Bighorn sheep are primarily diurnal (Jones 1950, pp. 54-57). They are primarily grazers; however, they may browse woody vegetation at times. Plants consumed include various grasses, browse, and forbs, depending on season and location (Wehausen 1980, pp. 80-93). Naturally occurring and mineral licks provide necessary minerals for bone and muscle growth.

While distribution of bighorn sheep is naturally fragmented on the landscape, the maintenance of migration corridors (space) is important to allow genetic exchange between Sierra Nevada bighorn sheep herds. The population ecology of bighorn sheep has been described as a metapopulation with geographically distinct herds interacting in a network (Schwartz
et al.
1986, p. 184; Bleich
et al.
1990, pp. 384-388). The movements of rams between herds can counteract the effects of inbreeding that can develop with small, isolated populations (Schwartz
et al.
1986, pp. 182-185).

Previous Federal Actions

On April 20, 1999, we published an emergency rule listing the Sierra Nevada DPS of the California bighorn sheep as endangered (64 FR 19300), providing emergency protection to the DPS until such time that we could complete the normal listing process. We also published a proposed rule to list the DPS as endangered on the same date (64 FR 19333). On January 3, 2000, we published a final rule listing the Sierra Nevada bighorn sheep as endangered (65 FR 20). The emergency rule stated that the designation of critical habitat was not determinable due to lack of information sufficient to perform the required analysis of impacts of the designation. In the final listing rule, we stated our revised determination that there is sufficient information to perform the required impact analysis and that the designation of critical habitat is prudent.

During the process of designating critical habitat for the Sierra Nevada bighorn sheep, we noticed that the final listing rule published in 2000 (65 FR 20) inadvertently listed this entity as a DPS rather than as a subspecies. While the listing rule addressed the DPS question, we failed to include the DPS language in the table found in the regulatory section of the rule. However, as stated above, based on the work of Wehausen and Ramey (2000, p. 156) and Wehausen
et al.
(2005, p. 217), the Sierra Nevada bighorn sheep is recognized as a subspecies, and the correct nomenclature is
Ovis canadensis sierrae
. Therefore, we are formally providing a taxonomic revision herein to amend the final listing rule to subspecies
Ovis canadensis sierrae
.

On July 30, 2003, we made available the Service's Draft Recovery Plan for the Sierra Nevada Bighorn Sheep (
Ovis canadensis californiana
) (68 FR 44808). On October 9, 2003, we reopened the comment period for the draft Recovery Plan (68 FR 58355). On February 13, 2008, we published a Notice of Availability for the final recovery plan (73 FR 8345).

On December 8, 2005, the Center for Biological Diversity filed a complaint based on the Service's failure to designate critical habitat for this subspecies within the time mandated under the Act (
Center for Biological Diversity
v.
U.S. Fish and Wildlife Service, et al.
Case No. 2:05-CB-02492-DFL-KJM). On June 6, 2006, the Service entered into a settlement agreement with the Center for Biological Diversity to submit a proposed critical habitat designation for this subspecies for publication in the
Federal Register
by July 17, 2007, and to submit a final determination on the proposed critical habitat designation for publication by July 17, 2008.

Our proposed critical habitat rule and taxonomic revision for the Sierra Nevada bighorn sheep was published in the
Federal Register
on July 25, 2007 (72 FR 40956). A notice of availability of the draft economic analysis (DEA) of the proposed critical habitat designation was published in the
Federal Register
on February 5, 2008 (73 FR 6684). This final rule satisfies the June 6, 2006, settlement agreement with respect to Sierra Nevada bighorn sheep.

For more information on previous Federal actions concerning Sierra Nevada bighorn sheep, refer to the final listing rule published in the
Federal Register
on January 3, 2000 (65 FR 20).

Summary of Comments and Recommendations

We requested written comments from the public on the proposed designation of critical habitat for the Sierra Nevada bighorn sheep published on July 25, 2007 (72 FR 40956). The 60-day comment period for the proposed rule closed on September 24, 2007. A request for a comment period extension was received from a private organization on August 20, 2007, and on October 9, 2007, the comment period was reopened until November 23, 2007 (72 FR 57276). A 30-day comment period was opened on the DEA and the proposed rule on February 5, 2008, and closed on March 6, 2008 (73 FR 6684). Comments and new information received in response to the proposed rule and the DEA were incorporated in the final rule as appropriate and summarized below.

During the comment periods for the proposed rule, we received a total of 28,181 (28,153 in support, 12 opposed, and 16 neutral) comments from Federal, State, and local governments, non-governmental organizations and private individuals. We received two requests for public hearings. The Inyo County Board of Supervisors made a request for a public hearing on August 7, 2007, as did two private individuals on August 29, 2007. A public hearing was held in Bishop, California, on October 25, 2007 (72 FR 57276). We received 12 oral testimonies from 12 individuals. Of these commenters, three who provided oral comments also submitted duplicative written comments. A request was made for a public workshop by the Mono County Board of Supervisors on September 5, 2007. We held two public meetings in Bridgeport and Bishop, California, on October 24 and 25, 2007, respectively (72 FR 57276).

Peer Review

In accordance with our policy published July 1, 1994 (59 FR 34270), we solicited expert opinions from three knowledgeable individuals with scientific expertise that included familiarity with the species and conservation biology principles. We received responses from two peer reviewers. In general, the peer reviewers concurred with our methods and conclusions and provided suggestions to improve the final critical habitat rule.

We reviewed all comments received from the peer reviewers and the public for substantive issues and new information regarding critical habitat for the Sierra Nevada bighorn sheep, addressed them in the following summary, and incorporated them into the final rule as appropriate.

Peer Reviewer Comments

(1)
Comment:
Both peer reviewers raised concern that the proposed designation did not adequately protect Sierra Nevada bighorn sheep from the possible introduction of disease from domestic sheep and goats. One suggested that the “absence of risk of disease transmission” should be explicitly included as a primary constituent element (PCE) as pneumonia caused by contact with domestic sheep or goats can be an overriding factor affecting habitat suitability.

Our Response:
Conservation of the Sierra Nevada bighorn sheep depends on addressing both habitat and non-habitat related threats. In terms of the consultation process under section 7(a)(2) of the Act, the Service is required to analyze both the threats to the individuals within a population and the threats to the PCEs of its designated critical habitat. Under the Special Management Considerations or Protection section, we have indicated that management of domestic livestock grazing practices that result in overgrazing or forage competition between these domestic species and Sierra Nevada bighorn sheep can be a threat. The concern for overgrazing or competition is a habitat-related threat associated with the PCEs (i.e., PCE 2). The potential for contact and the possible transmission of disease to bighorn sheep exists when domestic sheep or goats are present in critical habitat. Management of the threat of disease transmission between domestic sheep and goats and Sierra Nevada bighorn sheep is needed to conserve this species; however, this threat is not strictly a habitat-related threat. The potential effects of disease transmission will be addressed through section 7 consultation with Federal agencies under the jeopardy standard and through the section 9 prohibitions of the Act to the extent applicable. There would be no benefit gained from a critical habitat designation with respect to the effects of disease on individual Sierra Nevada bighorn sheep because the regulatory effects of critical habitat designations apply to adverse modification or destruction of habitat, not to effects that result in the mortality of individual Sierra Nevada bighorn sheep. Because the disease threat faced by the species is not habitat-based, there would be no practical benefit to including it as a PCE.

(2)
Comment:
One peer reviewer suggested that buffer zones be established around designated critical habitat for management of domestic sheep and goats because activities that could pose a risk of disease transmission do not need to occur directly within critical habitat to affect that habitat.

Our Response:
The units designated as critical habitat for the Sierra Nevada bighorn sheep contain the features essential for the conservation of this subspecies. It is not our practice to establish buffers around an area designated as critical habitat. As indicated under the Special Management Considerations or Protection section, domestic sheep and goat grazing may require management modifications to protect Sierra Nevada bighorn sheep in critical habitat in certain units. Any buffer distance recommended or suggested in a Federally proposed action involving domestic sheep or goat grazing adjacent to a designated critical habitat unit to reduce the potential threat of disease transmission to Sierra Nevada bighorn sheep would be taken into consideration during the jeopardy analysis of the consultation process under section 7 of the Act.

(3)
Comment:
One peer reviewer raised concern for an elevated risk of disease transmission with domestic sheep grazing on U.S. Forest Service

(USFS) lands as Sierra Nevada bighorn sheep wander between units.

Our Response:
We are aware of the potential risk of disease transmission due to contact between domestic sheep (and goats) and Sierra Nevada bighorn sheep. If a disease outbreak were to occur in a Sierra Nevada bighorn sheep population, it could be passed to other populations (units) because of, most likely, ram forays. This risk will increase if Sierra Nevada bighorn sheep numbers increase as expected due to continuing recovery actions. While we believe that this is an issue of management concern, we do not believe that this critical habitat designation necessarily affects the issue in any significant way. Please also see our response to comment (1).

(4)
Comment:
Both peer reviewers raised concern that the proposed critical habitat designation did not provide biologically based corridors or linkage zones for movements among Sierra Nevada bighorn sheep subpopulations. They were unclear how genetic exchange or colonization would be allowed with unconnected units of critical habitat.

Our Response:
Connectivity, within a critical habitat unit, is a PCE for the Sierra Nevada bighorn sheep (i.e., PCE 1). The current critical habitat configuration provides for long-term connectivity between groups within a particular unit. We recognize the importance of migration between critical habitat units, as discussed under Metapopulaton Structure in the Space for Individual and Population Growth and for Normal Behavior section. However, due to the current isolation of occupied herd units and extremely limited knowledge of various migration paths that Sierra Nevada bighorn sheep, especially rams, may have taken historically between units, we did not develop criteria that would capture migration corridors between units.

(5)
Comment:
One peer reviewer was concerned about the fine-scale mapping resulting in “finger-like” habitats for Units 1, 2, 3, 4, and 9. The concern was related to possible difficulties in managing such areas. The reviewer suggested the boundaries be redrawn to reduce sinuosity, possibly along watershed and or drainage boundaries.

Our Response:
The critical habitat units have been developed to be consistent with the herd units that the Sierra Nevada bighorn recovery plan identifies as essential for recovery of the subspecies. Those herd units were originally developed using expert opinion and information on current and historical bighorn sheep locations in the Sierra Nevada. Those units were later refined using a habitat selection model developed by University of California Davis and the California Department of Fish and Game (CDFG) (Johnson
et al.
2005). Based on our analysis of the biological needs of the subspecies, we believe that the herd units developed for the recovery plan capture those areas that contain the physical and biological features arranged in the appropriate quantity and spatial arrangement for the conservation of the subspecies.

It is important to remember that these critical habitat units are not being established as Sierra Nevada bighorn sheep preserves or management zones. These are regulatory designations of areas that contain the features essential to the conservation of the subspecies. Critical habitat would serve its regulatory role when analyzing a particular Federal action in the consultation process under section 7(a)(2) of the Act to determine if that action would adversely modify or destroy critical habitat by impacting the essential features within that unit to such a degree that the unit no longer serves its function for conservation.

It is possible that a Federal action immediately adjacent to these units (e.g., between “fingers”) could indirectly adversely modify critical habitat within the units. In such a situation, the action would be analyzed through the consultation process under section 7(a)(2) of the Act against the adverse modification standard. However, because our analysis has not identified essential features in these locations, unit boundary modification and designation of critical habitat therein would not be appropriate.

(6)
Comment:
One peer reviewer commented that the indicated 9 to 11 year lifespan for bighorn sheep seemed short.

Our Response:
We have modified the Background section of the final rule to more accurately reflect the observed lifespan for male and female bighorn sheep in the Sierra Nevada.

Comments From State Agencies

(7)
Comment:
California Department of Fish and Game (CDFG) suggested a PCE that identifies a “disease-free zone” because of the risk to Sierra Nevada bighorn sheep in proximity to domestic sheep.

Our Response:
Please see our response to Comment 1.

(8)
Comment:
CDFG recommended establishment of a buffer that excludes domestic sheep to ensure the integrity of the critical habitat for Sierra Nevada bighorn sheep and provide additional protections.

Our Response:
Please see our response to Comment 2.

(9)
Comment:
CDFG recommended more emphasis be placed on the use of fire to maintain critical habitat because fire is an integral part of the landscape.

Our Response:
The Special Management Considerations or Protection section identifies activities of Federal agencies or those with a federal nexus that may impact Sierra Nevada bighorn sheep and their habitat. The section is not meant to promote or discourage any particular activity. We indicated that it may be necessary in some of the critical habitat units to reduce forest cover to make habitat more suitable for Sierra Nevada bighorn sheep. Prescribed fire can be used as a tool to do this. Johnson
et al.
(2005, p. 34) indicate Sierra Nevada bighorn sheep could gain additional habitat with a reduction in forest cover. In addition, the final recovery plan (Appendix H, Genetic Management of Sierra Nevada Bighorn Sheep) provides a specific recommendation to use fire in addition to other methods to enhance habitat within herd units (Service 2007, p. 174). This would improve unit carrying capacity, as well as connectivity with adjacent herd units, providing better opportunities for genetic exchange between herds.

(10)
Comment:
California Department of Food & Agriculture (CDFA) commented that there is “still incomplete agreement in the scientific community” about disease transmission from domestic sheep to bighorn sheep, in general, such as how often it occurs and its role in disease epizootics in bighorn sheep. The CDFA agrees that a reasonable approach is to keep the two species separated. How such separation occurs and what measures are used to prevent possible contact are important to both the survival of Sierra Nevada bighorn sheep and the domestic sheep industry in Inyo and Mono Counties, California. The CDFA commented that further scientific findings will improve understanding of the true nature of respiratory disease in bighorn sheep, in general, and that interested parties should cooperate on common interests. They also noted that at the 111th Annual Meeting of the United States Animal Health Association (USAHA) in October 2007, a joint resolution passed recommending additional research and formation of a subcommittee. The College of Agriculture, Biotechnology and Natural Resources at the University of Nevada Reno (UNR) similarly mentions the USAHA resolution.

Our Response:
We are aware that disagreement continues regarding the potential for disease transmission to

occur between domestic livestock, especially sheep and goats, and bighorn sheep, in general, under range conditions. We have reviewed Resolution No. 15 that reads, “The United States Animal Health Association (USAHA) urges the United States Secretary of Agriculture and the United States Secretary of the Interior to seek resources through the President's budget to fund research to better elucidate the epidemiology and pathogenesis of bighorn/domestic sheep disease interactions so informed and effective management decisions can be made.” We, along with others, continue to seek answers to questions related to this disease transmission issue. We support continuing research efforts to address uncertainties and to assist in the decision-making process.

(11)
Comment:
The CDFA recommends consideration of the Western Association of Fish and Wildlife Agencies' (WAFWA) document, “Recommendations for Domestic Sheep and Goat Management in Wild Sheep Habitat”, dated June 21, 2007, and the University of California—Davis' “Quantifying the Risk of Disease Transmission from Domestic Sheep to Bighorn Sheep in the Sierra Nevada” in future determinations of effectively preventing the possibility of disease transmission between domestic sheep and Sierra Nevada bighorn sheep, in addition to working with livestock industry representatives.

Our Response:
We are aware of these documents and consider information contained within them during section 7 consultations, as appropriate. Other documents also support the effective separation of domestic sheep from bighorn sheep, in general, as a management tool to reduce the risk of contact and possible disease transmission (Wyoming State-wide Bighorn/Domestic Sheep Working Group 2004, pp. 7, 11; U.S. Forest Service 2006, pp. 18-19). Also, an expert science panel (U.S. Geological Survey and Bureau of Reclamation 2006) was convened in 2006 to discuss a risk analysis of disease transmission between domestic and bighorn sheep on the Payette National Forest in Idaho. The panel focused on science-based concerns raised by the risk analysis document, specifically the disease/mortality category, and developed six statements. References to concerns about domestic sheep also apply to domestic goats. Three of these key statements follow: “(1a) Scientific observation and field studies demonstrate that “contact” between domestic sheep and bighorn sheep is possible under range conditions. This contact increases risk of subsequent bighorn sheep mortality and reduced recruitment, primarily due to respiratory disease; (1b) The complete range of mechanisms/causal agents that lead to epizootic disease events cannot be conclusively proven at this point; and (1c) Given the previous two statements, it is prudent to undertake management to prevent contact between these species” (U.S. Geological Survey and Bureau of Reclamation 2006, p. 1). One panelist dissented and preferred “can increase risk” in statement 1a because it did not imply that any contact will result in disease transmission (U.S. Geological Survey and Bureau of Reclamation 2006, p. 1).

(12)
Comment:
The California Department of Transportation (CalTrans) states that roads are inconsistently addressed and that it is inappropriate to include state highway right-of-ways (ROWs) and facilities within critical habitat. It is recommended by CalTrans that State Route (SR) 120 in Unit 1 and SR 158 in Unit 2 be excluded from critical habitat.

Our Response:
When determining critical habitat boundaries for Sierra Nevada bighorn sheep, we made every effort to avoid including developed areas such as lands covered by buildings, paved areas, and other structures that lack PCEs for the Sierra Nevada bighorn sheep. The scale of the maps prepared under the parameters for publication within the Code of Federal Regulations may not reflect the exclusion of such developed areas. Any such features and the land under them inadvertently left inside critical habitat boundaries shown on the maps of this final rule have been excluded by text in the final rule and are not designated as critical habitat. Therefore, Federal actions limited to these areas would not trigger section 7 consultation, unless they may affect the species or PCEs in adjacent critical habitat.

We have determined, however, that the unpaved road right-of-ways of SR 120 from Unit 1 and SR 158 from Unit 2 do contain the features essential to the conservation of the Sierra Nevada bighorn sheep, and therefore meet the definition of critical habitat. CalTrans did not provide, nor are we aware of any additional information of the benefits of excluding ROWs based on ongoing or planned management of these ROWs, or how any on-going or planned management of the ROWs would benefit the conservation of the Sierra Nevada bighorn sheep or the sheep itself.

The Secretary may exclude an area from critical habitat under section 4(b)(2) of the Act after taking into consideration the economic impact, the impact on national security, and any other relevant impact if he determines that the benefits of such exclusion outweigh the benefits of designating such area as critical habitat, unless he determines that the exclusion would result in the extinction of the species concerned.

Because we are not aware of any information describing the benefits of excluding ROWs based on ongoing or planned management of these ROWs, or how any existing or planned management provides the same or better level of protection from adverse modification or destruction than that provided through a consultation under section 7 of the Act, we have determined that exclusion of these lands from the final designation of critical habitat pursuant to section 4(b)(2) of the Act is not appropriate at this time.

(13)
Comment:
CalTrans states that no bighorn sheep collisions with vehicles are listed in their accident database. This is contrary to a statement made in our proposed rule that a bighorn sheep collision with a vehicle had occurred in the past.

Our Response:
A CDFG employee was made aware of the collision we referenced in the proposed rule (72 FR 40956) through a third party. The employee contacted the motorist to obtain information about the November 2003 collision. The Sierra Nevada bighorn sheep ram was monitored after the collision by CDFG, and it subsequently died in January 2004. No formal report was made by CDFG to CalTrans (Stephenson 2008, p. 1).

(14)
Comment:
CalTrans indicates references to SR 190 should be corrected as SR 190 does not occur in or adjacent to critical habitat.

Our Response:
We erroneously indicated SR 190 occurred in or adjacent to Unit 10 in the Proposed Critical Habitat Designation and the Special Management Considerations or Protection sections. The road should have been indicated as Forest Route 16S02. This has been corrected in both sections.

(15)
Comment:
CalTrans states that, although an alignment has not been selected for the proposed Olancha/Cartago U.S. 395 project, an alternative might occur on the west side of Los Angeles aqueduct.

Our Response:
We appreciate this information. If the location for this new road construction occurs within designated critical habitat or may impact the Sierra Nevada bighorn sheep or its designated critical habitat, consultation under section 7 of the Act will occur as appropriate.

(16)
Comment:
The Nevada Department of Agriculture (NDOA) stated that the disease transmission risk assessment model by Clifford
et al.
(2007) is “questionable” as a tool for management and is a problem when serving as the basis of a critical habitat designation. The College of Agriculture, Biotechnology and Natural Resources at the University of Nevada Reno (UNR) similarly recommends that the disease risk assessment by Clifford
et al.
(2007) should not be used as the basis for designating Sierra Nevada bighorn sheep critical habitat.

Our Response:
We agree. Critical habitat as defined in section 3 of the Act is; the specific areas within the geographical area occupied by a species at the time it is listed in accordance with the Act, on which are found those physical or biological features essential to the conservation of the species and which may require special management considerations or protection; and specific areas outside the geographical area occupied by a species at the time it is listed, upon a determination that such areas are essential for the conservation of the species. Designation of critical habitat is not based on a single management issue and, in this case, the concern for transmission of diseases from the grazing of domestic sheep or goats in proximity to Sierra Nevada bighorn sheep did not serve as the foundation for this critical habitat designation. Domestic sheep grazing is a management issue that is properly addressed through the consultation process under section 7(a)(2) of the Act.

(17)
Comment:
The NDOA recommended that the critical habitat designation be suspended until the scientific basis has been established for disease transmission between domestic sheep and Sierra Nevada bighorn sheep.

Our Response:
We are designating critical habitat for Sierra Nevada bighorn sheep in accordance with the deadlines established by a court-approved settlement agreement. We agreed to submit to the
Federal Register
a final determination of critical habitat for Sierra Nevada bighorn sheep by July 17, 2008. We based our designation of critical habitat on the best scientific and commercial data available as required by Section 4 of the Act. Further, our Policy on Information Standards Under the Endangered Species Act (published in the
Federal Register
on July 1, 1994 (59 FR 34271)), the Information Quality Act (section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), and our associated Information Quality Guidelines provide criteria, establish procedures, and provide guidance to ensure that our decisions are based on the best scientific data available. We used published scientific literature and the expertise of Recovery Team members (including scientists from a variety of federal and state agencies, and other publics). We also solicited peer review from individuals familiar with bighorn sheep, in general, and related issues. We solicited new biological data, invited public participation during multiple comment periods, conducted a public hearing, and held informational meetings on the proposed rule. We have considered peer review, agency, and public comments received during the preparation of this final rule. Accordingly, we have used the best scientific and commercial information available in this designation. Designation of critical habitat is not based on a single management issue and, in this case, the concern for transmission of diseases from the grazing of domestic sheep or goats in proximity to Sierra Nevada bighorn sheep did not serve as the foundation for this critical habitat designation.

(18)
Comment:
The NDOA stated that uncertainties in general about bighorn sheep epizootics exist per the USAHA meeting in October 2007.

Our Response:
Please see our response to Comment 10.

(19)
Comment:
The NDOA stated that the occurrence of bighorn sheep disease and die-offs can be associated with bighorn sheep reaching peak numbers (Monello
et al.
2001). Stagnant bighorn sheep population numbers have occurred in association with predation by wolves and mountain lions. These factors affect bighorn sheep populations “permanently,” not just “temporarily” like domestic sheep grazing.

Our Response:
Bighorn sheep mortalities can be attributed to various factors as discussed below in the “Mortality Factors” section of this rule. These mortality factors may or may not affect bighorn sheep populations “permanently,” depending on numerous variables. Die-offs from diseases possibly transmitted from domestic sheep can have long-lasting effects by influencing subsequent population recruitment. Lambs born to surviving ewes can experience low survival rates for 3 to 5 years after the initial outbreak (Foreyt 1990, p. 100; Coggins and Matthews 1992; Ward
et al.
1992; Foreyt 1995; Hunter 1995a, as cited in Schommer and Woolever 2001, p. 3). We have added a short discussion in the Physical and Biological Features section related to these long-lasting impacts of pneumonia in bighorn sheep populations.

(20)
Comment:
The NDOA and UNR stated that climate and geographical factors play a role in the recovery of a species and that the “northern recovery unit” is neither suitable nor essential habitat in terms of winter range for the Sierra Nevada bighorn sheep due to its higher elevation and greater snow depths than more southern units.

Our Response:
As indicated in the Criteria Used to Identify Critical Habitat section, we used the following criteria to select areas occupied by the Sierra Nevada bighorn sheep at the time of listing for inclusion in critical habitat:

(a) Those areas occupied by the Sierra Nevada bighorn sheep at the time of listing (1999-2000) as indicated in the final listing rule (65 FR 20; January 3, 2000). In the final listing rule, we identified five subpopulations of Sierra Nevada bighorn sheep that existed: (1) Lee Vining Canyon (Mount Warren and Mount Gibbs Herd Units), (2) Wheeler Crest (Wheeler Ridge Herd Unit), (3) Mount Baxter (Sawmill Canyon and Mount Baxter Herd Units), (4) Mount Williamson (Mount Williamson Herd Unit), and (5) Mount Langley (Mount Langley Herd Unit) in Mono and Inyo counties, California (Wehausen 1999, pp. 1-7; 2000, pp. 1-6);

(b) Areas that are representative of the distribution of the Sierra Nevada bighorn sheep throughout the geographical range occupied at the time of listing with the goal of maintaining the subspecies' range of habitat and genetic variability; and

(c) Areas that allow for the continued existence of viable subpopulations under varying environmental conditions and that can serve as locations for source populations. The locations of all five subpopulations identified in the original listing rule continue to remain occupied today.

We have determined that the areas occupied at the time of listing continue to be occupied, contain features essential to the conservation of the subspecies (possess one or more PCEs such that the area supports one or more of the Sierra Nevada bighorn sheep's life processes) that may require special management, and provide sufficient habitat to protect these populations. Units 1 (Mount Warren) and 2 (Mount Gibbs) of the northern recovery unit meet these criteria.

More specifically, essential habitat is available for Sierra Nevada bighorn sheep in Units 1 (Mount Warren) and 2 (Mount Gibbs). This is not only based on historical data indicating their presence as far north as Sonora Pass (Grinnell and Storer 1924, as cited in Service 2007, p. 14), but also on the fact that these units also currently support

Sierra Nevada bighorn sheep herds. Mount Warren has a population of approximately 26 individuals, and Mount Gibbs has a population of approximately 8 individuals (Wehausen and Stephenson 2006, p. 7). The Mount Gibbs herd spends almost the entire year at elevations above 11,000 ft (3,353 m). In 2007, all ewes gave birth, and their lambs are known to have survived through at least September. This herd continues to survive and reproduce, expanding in numbers, although this alpine environment is no doubt harsher than lower-elevation areas. It is expected this herd will outgrow its carrying capacity of the alpine winter ranges and begin using lower-elevation winter ranges in the future (California Department of Fish and Game 2007, p. 2). Surveys (ground and aerial observations) of the Mount Warren herd conducted during the period from 2003 to 2007 indicate individuals are using this unit during every month of the year (California Department of Fish and Game files—monthly reports, Service files). In addition, a Resource Selection Probability Functions model was developed for summer and winter habitat and indicates an estimated 20.2 square kilometers (sq km) (7.8 square miles (sq mi)) and 9.4 sq km (3.6 sq mi), respectively, are available for Sierra Nevada bighorn sheep in the Mount Gibbs and Mount Warren units (Johnson
et al.
2005, p. 31). As discussed under the Primary Constituent Elements for Sierra Nevada Bighorn Sheep section of this rule, not all life history functions require all the PCEs, therefore, not all areas designated as critical habitat contain all of the PCEs. Units are designated based on sufficient PCEs being present to support one or more of the subspecies' life history requirements. This applies to both the occupied and unoccupied units designated.

(21)
Comment:
The NDOA and UNR noted that a memorandum to the Director of the Service from the U.S. Department of the Interior's Assistant Secretary for Fish and Wildlife and Parks, dated April 28, 2004, stated that critical habitat adds little additional conservation benefit to a listed species and designations must not be based on speculation or determinations that lack supporting data. Therefore, the designation of critical habitat is of “dubious value” as identified by your own agency.

Our Response:
Section 4(A)(3) of the Act requires that the Service identify those lands on which are found the physical or biological features essential to the conservation of the species that may require special management considerations or protection, and those areas outside the geographical area occupied by the species at the time of listing that are essential to the conservation of the species. In identifying those lands, the Service must consider the recovery needs of the species, such that, on the basis of the best scientific and commercial data available at the time of designation, the habitat that is identified, if managed, could provide for the survival and recovery of the species.

The identification of those areas that are essential for the conservation of the species and that can, if managed, provide for the recovery of a species is beneficial. The process of proposing and finalizing a critical habitat rule provides the Service with the opportunity to determine the physical and biological features essential to the conservation of the species within the geographical area occupied by the species at the time of listing, as well as to determine other areas essential for the conservation of the species. The designation process includes peer review and public comment on the identified physical and biological features and essential areas. This process is valuable to land owners and managers in developing conservation management plans for identified areas, as well as any other occupied habitat or suitable habitat that may not have been included in the Service's determination of essential habitat.

The consultation provisions under section 7(a) of the Act constitute the regulatory benefits of critical habitat. As discussed above, Federal agencies must consult with us on discretionary actions that may affect critical habitat and must avoid the destruction or adverse modification of critical habitat. Federal agencies must also consult with us on discretionary actions that may affect a listed species and refrain from undertaking actions that are likely to jeopardize the continued existence of such species. The analysis of effects to critical habitat is a separate and different analysis from that of the effects to the species. Therefore, the difference in outcomes of these two analyses represents the regulatory benefit of critical habitat. For some species, and in some locations, the outcome of these analyses will be similar, because effects on habitat will often result in effects on the species. However, the regulatory standard is different: The jeopardy analysis looks at the action's impact on survival and recovery of the species, while the adverse modification analysis looks at the action's effects on the designated habitat's contribution to the species' conservation. This may, in many instances, lead to different results and different regulatory requirements. Thus, critical habitat designations may provide greater regulatory benefits to the recovery of a species than would listing alone.

Another benefit of including lands in critical habitat is that designation of critical habitat serves to educate landowners, State and local governments, and the public regarding the potential conservation value of an area. In general, critical habitat designation always has educational benefits; however, in some cases, they may be redundant with other educational effects.

(22)
Comment:
The NDOA states that listing of Sierra Nevada bighorn sheep as an endangered species, subspecies, or even distinct metapopulation lacks scientific merit.

Our Response:
Please refer to our final rule listing the Sierra Nevada bighorn sheep published on January 3, 2000 (65 FR 20), which outlines our rationale for listing.

(23)
Comment:
The UNR stated designating critical habitat for Sierra Nevada bighorn sheep will lead to grazing allotment closures.

Our Response:
The designation of critical habitat for Sierra Nevada bighorn sheep does not automatically lead to closing allotments. For those areas on Federal lands, consultation under section 7 of the Act may be required to examine the effects of grazing on critical habitat. Specific actions by the managing Federal agency could include the elimination of, or restrictions on, livestock grazing in areas that overlap with critical habitat. Please also see our responses to Comments 24, 40, 41, and 42.

(24)
Comment:
UNR states that short-term, high intensity grazing by domestic sheep helps maintain forage production and fuel load accumulation. The regrowth of vegetation is more palatable and nutritious for Sierra Nevada bighorn sheep during the growing season as well as during winter. The removal of domestic sheep will lead to poorer forage production and an accumulation of fuels.

Our Response:
Regardless of any effects of grazing on fuel loads and forage quantity and quality, domestic sheep in some locations may pose a disease risk to Sierra Nevada bighorn sheep. The Service will recommend the removal of domestic sheep from allotments where contact with Sierra Nevada bighorn sheep cannot be prevented through section 7 of the Act. The Service has proposed actions in the recovery plan for Sierra Nevada bighorn sheep to maintain and enhance the

integrity of habitat through the careful use of fire and other habitat manipulations that do not involve domestic sheep grazing. These actions would include maintenance and enhancement of habitat in areas where domestic sheep may be removed to prevent contact with Sierra Nevada bighorn sheep.

Comments From Other Federal Agencies

(25)
Comment:
Yosemite National Park raised a concern about any reduction in the proposed critical habitat and protection of the Sierra Nevada bighorn sheep in the “northern recovery units” which would constitute the “Yosemite herd.” Sierra Nevada bighorn sheep in the northern areas are the ones most likely to reoccupy habitat in Yosemite, filling an ecological void and offering park visitors the opportunity to observe these animals.

Our Response:
We have not reduced the area of designated critical habitat for the two units (Mount Warren and Mount Gibbs) that occur within the northern recovery unit because they meet our criteria for identifying critical habitat. These units contain the features essential to the conservation of the Sierra Nevada bighorn sheep and require special management. We also did not identify any areas within these units where the benefits of exclusion outweighed the benefits of inclusion. Please also see our response to Comment 20.

(26)
Comment:
Yosemite National Park supports the proposed critical habitat designation and taxonomic revision but recommends expanding critical habitat to cover all areas currently occupied by Sierra Nevada bighorn sheep, accommodate further range expansion, and provide buffers between domestic sheep and Sierra Nevada bighorn sheep to prevent disease transmission.

Our Response:
As indicated in our response to Comment 2, it is not our practice to establish buffers around an area designated as critical habitat. A buffer distance indicated in a Federally proposed action involving domestic sheep or goat grazing near designated critical habitat would be considered during the consultation process under section 7 of the Act. As indicated in our response to Comment 36, critical habitat should not include the entire area that can be occupied by the species. We based our designation on the Recovery Team's delineation of essential habitat and as indicated in our final approved recovery plan (Service 2007, p. 41). For a more thorough discussion of these topics, please see our responses to Comments 2 and 36.

(27)
Comment:
Sequoia and Kings Canyon National Parks indicated their commitment to preserving and restoring natural ecosystems. They view Sierra Nevada bighorn sheep as an essential component that has been lost from much of its historical range within the Parks. By policy and law there is a commitment to working with the Service and other agencies to help restore the Sierra Nevada bighorn sheep to their former range and abundance. Sequoia and Kings Canyon National Parks fully support the proposed critical habitat designation.

Our Response:
We appreciate the support and look forward to continuing to work with the National Park Service and others to conserve the Sierra Nevada bighorn sheep.

(28)
Comment:
The USFS suggested that designating critical habitat does not provide any additional benefit to a species and that it unnecessarily adds to USFS workload and may lead to re-initiation of section 7 consultation for critical habitat where a consultation has already been completed.

Our Response:
Designating critical habitat identifies those areas that contain the features that are essential to the conservation of a particular species, thus signaling to Federal agencies to consider the species' conservation in the design and implementation of their management actions. The designation provides guidance on why these areas need special management considerations or protection and indicates activities that are likely to adversely modify or destroy critical habitat. The designation of critical habitat assists the recovery process by providing information on how actions might impact the species' habitat. Including USFS lands as critical habitat is significant because this will assist in maintaining the Service's role in reviewing potential future impacts to areas that are important for the conservation of Sierra Nevada bighorn sheep populations. Lands administered by the USFS contain a substantial portion of habitat that is essential for the conservation of Sierra Nevada bighorn sheep. Designation of critical habitat may also provide protection for unoccupied habitat that may not otherwise undergo the section 7 consultation process due to species' absence. Considering whether proposed future projects will result in the destruction or adverse modification of critical habitat in addition to the jeopardy analysis will require some additional analysis during the section 7 consultation process.

(29)
Comment:
The USFS indicated the 2001 Record of Decision for the Ansel Adams, John Muir, and Dinky Lakes Wilderness Plans considered various impacts on Sierra Nevada bighorn sheep and their habitats.

Our Response:
We appreciate this information and have reviewed this document. Only one item was found directly related to management of the Sierra Nevada bighorn sheep. This addressed the closure of Sierra Nevada bighorn sheep habitat to dogs. As indicated in the Special Management Considerations or Protection section, dogs (with their associated recreation activities) are a potential threat to Sierra Nevada bighorn sheep critical habitat. At issue are the effects of Wilderness Plans, associated Forest Land and Resource Management Plans, and ongoing activities on USFS lands on federally listed species, including the Sierra Nevada bighorn sheep. The goal of these plans is to describe a strategic direction for the management of the wilderness areas over a long period of time (15-20 years). The plans do not make any decisions regarding USFS site-specific project proposals for implementing the land management plans nor do they require managers to implement any specific conservation activities.

(30)
Comment:
The USFS stated that management direction was established to restrict dogs in Sierra Nevada bighorn sheep habitat located in the Mt. Baxter and Mt. Williamson California Bighorn Sheep Zoological Areas on the Inyo National Forest.

Our Response:
Please see our response to Comment 29. These statements also apply to FS Order No. 04-81-3 which established these zoological areas in 1981.

(31)
Comment:
The USFS commented that the proposed critical habitat designation does not establish migration corridors between the units though migration is identified as important. While paths that rams may take between units or groups may be unpredictable, the final designation would be strengthened if it were to identify dispersal and movement corridors that are integral to the habitat elements.

Our Response:
Please see our response to Comment 4.

(32)
Comment:
The USFS requests clarification on why disease transmission from domestic livestock grazing is included as a stochastic event.

Our Response:
This has been corrected. We have removed those references specifically identifying the risk of disease transmission from domestic livestock from (3) of the Criteria Used To Identify Critical

Habitat section. The remaining reference addresses various diseases of North American wild sheep.

(33)
Comment:
The USFS suggested that the proposal is not as clear as it should be regarding the effects of disease transmission on Sierra Nevada bighorn sheep populations. Incorporating disease-associated risks into a PCE would strengthen the proposal.

Our Response:
We have added some additional information in the biological background of the Primary Constituent Elements section of this rule. Please also see our response to Comment 1.

(34)
Comment:
The USFS stated that while it is important to decrease the degree of habitat fragmentation in the Sierra Nevada, the designation of critical habitat does not actually do that.

Our Response:
Designation of critical habitat offers protection from various impacts which may be proposed on the landscape. We believe designating critical habitat in 12 units ranging from 22,037 ac (8,918 ha) to 80,966 ac (32,766 ha) does reduce potential habitat fragmentation. Providing protections for currently unoccupied areas that decrease the distances between occupied areas also assists in reducing habitat fragmentation. The protection of these unoccupied habitats will allow for future establishment of herds in these habitats through translocation or natural colonization, which will help to increase gene flow between populations. The ability to establish and maintain regular gene flow between populations of Sierra Nevada bighorn sheep is essential to their recovery. Reducing habitat fragmentation through protection of these currently unoccupied habitats under a critical habitat designation is essential to the subspecies' conservation.

(35)
Comment:
The USFS recommended that the section discussing wildfire be clarified to resolve apparent contradictions identifying which management actions and stochastic events are considered potentially beneficial or detrimental to critical habitat.

Our Response:
Fires can have beneficial, as well as detrimental, effects depending on the situation including location, severity, and extent. As indicated in the Special Management Considerations or Protection section, management actions such as the suppression of wildfires over the past decades has allowed for encroachment of forested habitat into Sierra Nevada bighorn sheep habitat. This has been detrimental to the Sierra Nevada bighorn sheep by increasing habitat for predator concealment. Management actions such as prescribed fires are carried out in a planned, controlled manner in a specific area and can be beneficial to Sierra Nevada bighorn sheep by reducing selected forested habitat that can conceal predators. Stochastic events such as wildfires can be beneficial or detrimental. For example, in July 2007, lightning sparked fires in Sierra Nevada bighorn sheep habitat in the Mount Baxter herd unit. The Seven Oaks Fire burned the majority of the low elevation winter range [<8,000 ft (2438 m)] (California Department of Fish and Game 2007, p. 5). The fire may benefit Sierrra Nevada bighorn sheep by opening up forested areas. The fire also scorched the above ground vegetation. With appropriate moisture levels gained over the winter, sufficient forage may become available. The CDFG personnel intend to evaluate the effects of this fire on forage availability and quality and habitat selection by Sierra Nevada bighorn sheep in this area (California Department of Fish and Game 2007, p. 6).

(36)
Comment:
The USFS mentioned that the Mount Warren unit may not extend northward enough to encompass currently occupied habitat as a few Sierra Nevada bighorn sheep have occurred in the northern areas.

Our Response:
According to 16 U.S.C. 1532(5)(C), “critical habitat should not include the entire geographic area that can be occupied by the threatened or endangered species” absent a finding of exceptional circumstances by the Secretary of the Interior. We based our critical habitat designation on the Recovery Team's delineation of essential habitat and as indicated in our final approved recovery plan (Service 2007, p. 41). The Recovery Team did not include all areas that have documented historical and current use by Sierra Nevada bighorn sheep, but only those areas regarded as essential for the recovery of the Sierra Nevada bighorn sheep. We used the Recovery Plan to assist in the preparation of the proposed and final critical habitat designations. Integration of these processes strengthens the scientific basis and minimizes the potential discrepancies between the two. Please refer to the final recovery plan for a more detailed discussion of the recovery strategy. The basis for the critical habitat delineation is described in the Criteria Used to Identify Critical Habitat section of this rule. We did not include the areas to the north of Mount Warren or the Bubbs Creek area as critical habitat as these areas did not meet our criteria for inclusion as critical habitat for Sierra Nevada bighorn sheep. Not including these areas within the critical habitat designation does not preclude the continued occupancy or expansion of Sierra Nevada bighorn sheep into these areas. We believe the units designated as critical habitat contain sufficient PCEs to support the behaviors we have determined are essential for the conservation of the subspecies and population criteria as identified in the final recovery plan. Therefore, we have not included these additional areas as critical habitat in the final rule.

(37)
Comment:
The USFS stated there appear to be some biological contradictions among units that were included and those that were “excluded” in the critical habitat designation. For example, the Bubbs Creek Herd Unit is currently occupied yet is excluded; and the Mount Warren area does not provide access to low elevation winter range yet is included.

Our Response:
No areas were excluded from the final critical habitat designation. We did not designate four herd units that were mentioned in the Sierra Nevada bighorn sheep final recovery plan as they were not considered essential in the plan. Please refer to the Criteria Used to Identify Critical Habitat section for our detailed rationale for not designating these areas. Please also refer to our responses to Comments 36 and 50.

(38)
Comment:
The USFS suggested that the ramifications of global climate change be considered in the proposal.

Our Response:
As indicated in the final recovery plan (Service 2007, p. 41), two northern herd units, Mount Warren and Mount Gibbs, are included as essential to the conservation of the Sierra Nevada bighorn sheep, in part, to protect this subspecies and its habitat across a range of latitudes. Climate change may induce ecological changes in the essential herd units in the south. Populations in the northern latitudes can help guard the rangewide population against loss of populations in areas that occur further south.

General Comments

Comments Related to Designation and Sierra Nevada Bighorn Sheep Biology and Management

(39)
Comment:
A few commenters stated concern for the areas of overlap between proposed critical habitat and Federal domestic sheep grazing allotments. The commenter requested that these areas of overlap (six areas with an estimated 1,000 ac (405 ha) be excluded from the critical habitat designation. If these areas are not excluded, the commenter requested specific justification and evaluation of

the habitat including what contribution these areas make to Sierra Nevada bighorn sheep and why their elimination would be detrimental to recovery efforts.

Our Response:
We have determined that there are seven areas of overlap between designated critical habitat and Federal domestic sheep grazing allotments [Bureau of Land Management (BLM) or USFS], not six as the commenter stated. These allotments include: (1) Dunderberg; (2) Copper Mountain; (3) Bloody Canyon; (4) McGee; (5) Sherwin; (6) Round Mountain; and (7) Rock Creek-Hilton Unit. The overlap areas total approximately 2,209 ac (894 ha). At the time critical habitat was proposed, all of these allotments were considered vacant, inactive, or unalloted with the exception of the Rock Creek-Hilton Unit. The Rock Creek-Hilton Unit is the only active domestic sheep grazing allotment that overlaps with designated critical habitat. This overlap is 0.9 ac (0.4 ha).

In our proposed rule and this final rule, we included domestic livestock grazing as a threat to the essential features that may need special management considerations or protection within designated critical habitat units. Consultation under the Act by Federal agencies may be necessary if proposed actions may adversely affect the Sierra Nevada bighorn sheep or its critical habitat. We have determined that all seven overlap areas are essential to the Sierra Nevada bighorn sheep because they contain the features essential to the conservation of the subspecies and meet the definition of critical habitat. Please see the Criteria Used To Identify Critical Habitat section for more information. One of our objectives is to provide consistency between critical habitat designation and the essential habitat indicated in the final recovery plan (Service 2007, p. 41).

The Secretary may exclude an area from critical habitat under section 4(b)(2) of the Act after taking into consideration the economic impact, the impact on national security, and any other relevant impacts if he determines that the benefits of such exclusion outweigh the benefits of designating such area as critical habitat, unless he determines that the exclusion would result in the extinction of the species concerned.

We have previously consulted with the USFS on grazing issues in Units 1, 2, and 4 and have determined that those activities were either not likely to adversely affect the Sierra Nevada bighorn sheep or were not likely to jeopardize the continued existence of the subspecies. Since critical habitat has not been previously proposed or designated for this subspecies, it is anticipated that Federal agencies will initiate section 7 consultation as appropriate, for any activities that may affect Sierra Nevada bighorn sheep or its critical habitat. These consultations would include an analysis of destruction or adverse modification of critical habitat as well as a jeopardy analysis. Considering whether proposed future projects will result in the destruction or adverse modification of critical habitat in addition to the jeopardy analysis will require some additional analysis during the section 7 consultation process. We do not believe that the additional analysis to determine whether an action will result in the destruction or adverse modification of critical habitat constitutes a substantial burden.

According to the final EA, post-designation baseline costs for grazing are estimated at $12.5 million (undiscounted) over the next 20 years, $9.6 million applying a 3 percent discount rate, or $7.1 million applying a 7 percent discount rate. Post-designation incremental costs for grazing consultations are estimated to be $97,600 (undiscounted) over the next 20 years, $74,800 applying a 3 percent discount rate, or $55,300 using a 7 percent discount rate.

These impacts are primarily due to the predicted yearly formal section 7 consultations between the Service and the USFS on allotments in proximity to critical habitat in Unit 1. There are no forecasted post-designation incremental impacts for the other critical habitat units. Thus, costs are not considered to be disproportionate. We will continue to work with the USFS, BLM, and permittees to address concerns related to the Sierra Nevada bighorn sheep during the section 7 consultation process as appropriate.

Units 1, 2, and 4 all contain the features essential to the conservation of the Sierra Nevada bighorn sheep. The benefits of including these units in critical habitat include access to areas for foraging (summer and winter), mating, lambing, bedding, predator avoidance, seasonal elevational movements, and mineral licks.

We have considered the request by the commenters to exclude the areas listed above and the relevant impacts of designation. Based on this record, we have chosen not to exclude these areas.

(40)
Comment:
Domestic sheep producers have been working with Federal agencies informally to prevent contact between domestic sheep and Sierra Nevada bighorn sheep. These practices should be formalized by the grazing permit process.

Our Response:
Federal agencies that issue grazing permits that may affect federally listed species consult with the Service as required under section 7 of the Act, as appropriate, even in the absence of critical habitat. The purpose of the section 7 consultation process is to analyze the effects of an action (e.g., the issuance of a grazing permit) to determine if the action will jeopardize the continued existence of the listed species, to provide reasonable and prudent measures to avoid and minimize the impact of incidental take, and, if necessary, to provide reasonable and prudent alternatives to avoid jeopardy. With the designation of critical habitat, Federal agencies will also determine whether the proposed action will adversely modify or destroy critical habitat under this process. The Service has, and will continue to, work with Federal agencies and grazing permittees to address concerns related to the Sierra Nevada bighorn sheep during the section 7 consultation process, as appropriate. Outside of the section 7 consultation process, the Service has the ability to provide comments to other Federal agencies during National Environmental Policy Act (NEPA) review.

(41)
Comment:
Some commenters urged the continued authorization of domestic sheep grazing on lands designated as critical habitat. Others did not support domestic sheep grazing within these areas.

Our Response:
The designation of critical habitat does not automatically eliminate or place restrictions on domestic sheep grazing or other land use activities in areas that overlap with critical habitat. For those areas on Federal lands, consultation under section 7 of the Act may be appropriate. Please also see our response to Comments 23 and 39.

(42)
Comment:
A concern was raised that elimination of cattle grazing at higher elevations may occur due to the designation of critical habitat.

Our Response:
There are several Federal cattle grazing allotments (USFS and BLM administered lands) that overlap with critical habitat designation in both occupied and unoccupied units. The designation of critical habitat does not automatically eliminate or place restrictions on cattle grazing or other land use activities in areas that overlap with critical habitat. To date, we have not conducted section 7 consultations with other Federal agencies related to impacts of cattle grazing to Sierra Nevada bighorn sheep. However, if the Federal agencies determine that

issuance of grazing permits may affect Sierra Nevada bighorn sheep or its critical habitat, they will request consultation under section 7 of the Act.

(43)
Comment:
One commenter recommended that managed cattle grazing be “protected,” or retained, within critical habitat as a recovery tool.

Our Response:
There are currently several Federal cattle grazing allotments located within designated critical habitat. We do not know the amount of private lands where cattle grazing may also occur within critical habitat, but the total amount is not more than 1,005 ac (407 ha). Cattle grazing on Federal allotments within critical habitat should be reviewed under section 7 of the Act if it may affect Sierra Nevada bighorn sheep or its critical habitat. In addition, the suggestion that Federal domestic sheep grazing allotments could be converted to cattle grazing allotments to reduce the potential impacts of disease transmission from domestic sheep to Sierra Nevada bighorn sheep has been raised. Allotment conversion would require Federal agency involvement, as well as willingness and ability on the part of the permittee. This suggestion has been included in the final recovery plan for the Sierra Nevada bighorn sheep (Service 2007, pp. 64 and 70).

(44)
Comment:
Habitat protection and disease issues are different and should be treated separately.

Our Response:
These issues are treated differently as indicated by the definition of critical habitat stated in this rule under the Critical Habitat section and the activities addressed under the Special Management Considerations or Protection section.

(45)
Comment:
Why is 417,000 ac (168,757.6 ha) needed for 400 Sierra Nevada bighorn sheep?

Our Response:
The critical habitat designation of 417,577 ac (168,992 ha) is not only for the estimated 400 Sierra Nevada bighorn sheep's current population. The area of critical habitat is also for the additional animals that are needed for the recovery of the species and to provide sufficient area for their life history requirements. According to the final recovery plan, there should be an estimated minimum total of 305 females at least 1 year of age throughout the four recovery units at the time of delisting (Service 2007, p. 47). Based upon a natural adult sex ratio of about 70 males:100 females, the minimum total population (both sexes) is estimated to be 520 adults at delisting. Since this number is based on a minimum requirement for each recovery unit, the total population is likely to be higher. This number would be higher still with young of the year also included in the total (Service 2007, p. 44).

(46)
Comment:
Why is it necessary to have critical habitat if section 7 is already being used?

Our Response:
Under section 7(a)(2) of the act, Federal agencies must consult with the Service to ensure that their actions do not jeopardize the continued existence of listed species. By designating critical habitat, section 7 of the Act also protects the recovery needs of the species by requiring Federal agencies to ensure that their actions will not result in the destruction or adverse modification of designated critical habitat. For additional information, please also refer to our response to Comment 28.

(47)
Comment:
Several comments were received related to recreational activities and what the designation of critical habitat signifies now and in the future. Some commenters recommended that snowmobiles and off-road vehicles be prohibited in critical habitat and existing routes be closed. Others thought it was appropriate to “exclude” dogs or require them to be on leashes at all times. Others recommended that no new off-road vehicle trails be built in critical habitat. Others expressed support for our “exclusion” of particular recreational areas from the designation. Others requested no restrictions on backcountry use. Others wondered if public use would continue as it does currently. Others recommended that any restrictions apply to both guided and non-guided public alike. A few commenters suggested that the rule be changed to state that most, if not all, types of recreation were non-threatening to Sierra Nevada bighorn sheep, especially when bighorn sheep are not overtly threatened and have access to escape terrain. Some suggested continued monitoring of both Sierra Nevada bighorn sheep and the effects of people's interaction with them as recreation is an important component of the economy.

Our Response:
Proposed and final rules designating critical habitat do not automatically eliminate or place restrictions on any recreational activities or opportunities within critical habitat. This rule did not “exclude” any particular recreational area from the critical habitat designation; these areas were not included because they did not meet our criteria for designating critical habitat for Sierra Nevada bighorn sheep. For more information on the criteria used to delineate critical habitat please see the Criteria Used to Identify Critical Habitat section in this rule. The designation of critical habitat is not a management plan, nor does it put in effect or restrict management activities. The Special Management Considerations or Protection section of this final rule lists actions that may impact the PCEs for Sierra Nevada bighorn sheep and serves as a guide to Federal agencies that may conduct or permit actions within designated critical habitat. The USFS and National Park Service may have restrictions (e.g., quotas, seasonal closures, dog prohibitions or leash requirements) already in place in some areas to address resource concerns, as well as to reduce impacts to wildlife, including Sierra Nevada bighorn sheep. Due to areas of rugged terrain and inaccessibility, as well as wilderness designations, some recreational activities (e.g., snowmobiling, off-road vehicle use) are not possible within portions of the designated critical habitat. Other activities, such as rock and ice climbing and peak bagging, are specific to these rugged areas. We encourage the public to enjoy the Sierra Nevada while treating it with respect. With proper management, recreational activities can or may be compatible with Sierra Nevada bighorn sheep conservation and recovery. It is the responsibility of the Federal agencies to review the various kinds of recreational activities currently allowed, where they are allowed, and the seasonal use of these areas among other things, to determine if these activities may result in the destruction or adverse modification of critical habitat. Federal agencies will review all proposed actions in accordance with section 7(a)(2) of the act in light of possible increases of sheep-human interaction due to both increasing Sierra Nevada bighorn sheep and human populations, and subsequent habitat use changes. We will continue to work with Federal agencies and those who need Federal permits through the section 7 consultation process to address recreational activities that may affect Sierra Nevada bighorn sheep habitat. We have added some additional information related to bighorn sheep and human interactions in the Special Management Considerations or Protection section in this rule. As previously stated, we will continue to recommend that studies be implemented to clarify any potential impacts of different recreational activities on Sierra Nevada bighorn sheep and their habitat to assist with decision-making processes.

(48)
Comment:
While several commenters expressed support for the critical habitat designation as proposed,

a majority of commenters expressed a desire that additional lands be included. Some offered a general statement to expand the critical habitat designation while others provided more specific statements of additional areas to be included. These recommendations were to include: (1) All historical and currently occupied areas; (2) areas north of Mount Warren; (3) all occupied and unoccupied habitat essential for survival and recovery; (4) all areas identified as of recovery value in the recovery plan; and (5) the Bubbs Creek area.

Our Response:
Please see our response to Comment 36.

(49)
Comment:
Many ranchers have lost faith in the Service's ability to implement Sierra Nevada bighorn sheep recovery and re-introduction efforts while protecting ranching operations. For example, “a rancher lost his Bloody Canyon USFS Allotment, although previously promised that Sierra Nevada bighorn sheep recovery would not require any changes in the use of [the Bloody Canyon] allotment.”

Our Response:
The “promise” referred to in the comment above relates to two letters, one written by the CDFG dated August 27, 1984, and addressed to the Inyo National Forest, and the other written by the Forest Service dated December 20, 1989, and addressed to the permittee. It is important to note that these letters were written by other agencies prior to the Federal listing of the Sierra Nevada bighorn sheep in 2000, and prior to the Service's involvement with this subspecies. Since the listing of the subspecies and development of the recovery plan, substantial new information has been gathered regarding areas used by Sierra Nevada bighorn sheep. The Service has and will continue to coordinate with individual ranchers, the State of California, and other Federal agencies to promote the recovery of Sierra Nevada bighorn sheep while balancing the needs of affected permittees and conservation of the subspecies through the section 7 consultation process. Also, please refer to our response to Comment 40.

(50)
Comment:
The areas of Twin Lakes, Green Creek, Coyote Ridge, and Bubbs Creek should not be “excluded” from critical habitat designation.

Our Response:
These four areas were not “excluded” from the critical habitat designation. These four areas were not included within our critical habitat designation because they were not determined to be essential for the conservation of the Sierra Nevada bighorn sheep. Please see the Criteria Used to Identify Critical Habitat section for our rationale.

(51)
Comment:
Some commenters agreed that the four existing plans [Sierra Nevada Bighorn Sheep Recovery and Conservation Plan (Sierra Nevada Bighorn Sheep Interagency Advisory Group 1984); the Bighorn Sheep Management Plan (National Park Service 1986); the Inyo National Forest Resource & Management Plan (U.S. Forest Service 1988); and A Conservation Strategy for Sierra Nevada Bighorn Sheep (Sierra Nevada Bighorn Sheep Interagency Advisory Group 1997)] should not result in the exclusions of lands covered by these plans from critical habitat designation. One commenter thought we should exclude these lands because the plans already exist and there are recovery projects in place.

Our Response:
We have indicated our rationale for not excluding areas covered by these four plans as indicated in the Application of section 4(b)(2) of the Act section of this final rule. These plans are general in nature and reflect our knowledge at that time. All plans were prepared prior to the listing of the subspecies. Specific recovery projects and actions are a result of the draft and final recovery plans, not these four documents.

(52)
Comment:
Does the designation of critical habitat allow for management of mountain lions?

Our Response:
The designation of critical habitat will not affect the management of mountain lions as their control is not a habitat-based threat. The encroachment of vegetation that provides cover for predators of the Sierra Nevada bighorn sheep is a habitat-based threat, and actions to manage the vegetation encroachment may require special management considerations or protection as discussed in this rule. We, along with CDFG, recognize the role that mountain lions have played in the status of the Sierra Nevada bighorn sheep. Beginning in 2000, CDFG began placing radio collars on mountain lions near Sierra Nevada bighorn sheep ranges and monitoring them to assist in the removal of selected individuals to benefit Sierra Nevada bighorn sheep. Mountain lions are a necessary and important part of the Sierra Nevada ecosystem; Sierra Nevada bighorn sheep have evolved with this predator on the landscape. As the numbers of Sierra Nevada bighorn sheep increase with recovery, the need for mountain lion control specifically for the benefit of Sierra Nevada bighorn sheep should be reduced and eventually eliminated.

(53)
Comment:
One commenter questioned whether land use managers would be allowed to use prescribed burning and logging within critical habitat.

Our Response:
Prescribed burning and logging would be considered habitat-based activities that could affect the PCEs. Federally proposed actions would be analyzed during the section 7 consultation process as appropriate. As indicated in the rule, prescribed burning can benefit Sierra Nevada bighorn sheep by increasing visibility of the landscape. These activities may be able to proceed as determined during the section 7 consultation process.

(54)
Comment:
Sierra Nevada bighorn sheep deaths due to tranquilization and horns being ripped off during research activities are a management problem.

Our Response:
Since 2001, when CDFG's Sierra Nevada Bighorn Sheep Recovery Program was established, there have been 44 deaths (2 rams, 2 ewes) among the approximately 150 captures conducted to date (2.7 percent) (Stephenson 2008, p. 1). Sierra Nevada bighorn sheep are not tranquilized. One ewe is known to have broken a horn sheath (not horn) during capture activities. Documentation of injuries or deaths occurring during capture activities must be provided to the Service under CDFG's section 10(a)(1)(A) recovery permit issued under the Act. The reporting documentation must describe in detail the circumstances that led to the injury or mortality and include a description of the changes in activity protocols that will be implemented to reduce the likelihood of such an injury or mortality from occurring again. All incidents are reviewed by the Service and capture procedures are changed, if necessary, to reduce subsequent injuries or deaths. The recovery permit allows for a determined level of incidental take to occur on an annual basis that will not jeopardize the continued existence of the species. In addition, the importance and recovery value of information obtained during these activities and subsequent monitoring of Sierra Nevada bighorn sheep is utilized in our population management and rangewide recovery management decisions. Although we acknowledge that certain levels of take may occur when conducting authorized activities for Sierra Nevada bighorn sheep, we make every effort to minimize take to the maximum extent practicable.

(55)
Comment:
The Special Management Considerations and Protection section provides no assurances that existing development

activities, livestock grazing, mining, recreation, etc. can continue.

Our Response:
The Special Management Considerations or Protection section of this rule identifies the types of activities that could impact the PCEs in the designated critical habitat units. It is not meant to provide assurances but to identify areas of concern for Federal agencies to determine if a proposed action may affect Sierra Nevada bighorn sheep habitat and should be addressed under the section 7 consultation process. Please also refer to our response to Comment 28.

(56)
Comment:
Explicit management recommendations for off-road vehicles and domestic sheep grazing should be included in the final rule.

Our Response:
In the Special Management Considerations or Protection section, we indicate various management activities that may affect designated critical habitat. We purposefully do not provide explicit management recommendations for the various activities so that the action agency and the Service can determine appropriate measures on a case-by-case basis during the section 7 consultation process.

(57)
Comment:
The purchase of private lands should be a priority to reduce the concern of disease transmission from domestic to Sierra Nevada bighorn sheep.

Our Response:
There is little private land (1,005 ac (407 ha)) within the units designated as critical habitat. We do not know the extent of private acreage, if any, that provides domestic sheep or goat grazing. The purchase of private lands for the purposes of critical habitat is not within the scope of this final rule; however, purchase of private lands from willing sellers would be an option for recovery purposes and could, in some areas, reduce the potential of disease transmission from domestic to Sierra Nevada bighorn sheep.

(58)
Comment:
One commenter stated there is little definitive information or predictive ability regarding avalanches in almost all areas recommended as critical habitat. The rule should reflect real and practical activities not speculative ones such as avalanche control.

Our Response:
We agree that it is difficult to predict and manage avalanche danger in many areas of the Sierra Nevada, and we are not proposing a comprehensive plan for control of avalanches to protect Sierra Nevada bighorn sheep. However, opportunistic management of avalanche danger in some locations may be possible (e.g., SR 120 corridor). Mortality of Sierra Nevada bighorn sheep from avalanches is a real and documented threat that can result in losses of large numbers of individuals. We are working to buffer the subspecies against these stochastic losses by establishing additional populations that spread the risk across a larger area. We are also working to improve winter range habitat, to reduce winter range predation, and to increase population sizes. The goal of these activities is to increase use of winter range by Sierra Nevada bighorn sheep, so that they are not at high elevation locations during the season of highest avalanche danger. However, we do not rule out the possibility of recommending avalanche control in areas where we believe it might be effective in protecting some populations that are not utilizing winter range.

(59)
Comment:
Sheep crossing signs should be installed in the Tioga Pass and June Lake Loop areas for the safety of motorists as well as the Sierra Nevada bighorn sheep.

Our Response:
Sign placement is outside the scope of this rule. However, the Service is supportive of continuing efforts to increase public awareness of Sierra Nevada bighorn sheep.

(60)
Comment:
The critical habitat overlaps existing wilderness designations creating another layer of bureaucracy.

Our Response:
Some of the critical habitat units do overlap portions of wilderness; however, these two designations do not achieve the same goals. The Wilderness Act of 1964 created a National Wilderness Preservation System. Federal lands designated by Congress as “wilderness areas” are to be “administered for the use and enjoyment of the American people in such manner as will leave them unimpaired for future use as wilderness, and as to provide for the protection of these areas, the preservation of their wilderness character, and for the gathering and dissemination of information regarding their use and enjoyment as wilderness.” A wilderness designation prohibits commercial enterprises; permanent roads (with some exceptions); use of motorized vehicles, equipment, and boats; aircraft landing; temporary roads; and structures or installations (with some exceptions). It does not prohibit activities such as some mining and associated activities, water resource and development and their associated support facilities, grazing, and recreational activities. The Wilderness Act also did not affect the “jurisdiction or responsibilities of the several States with respect to wildlife and fish in the national forests.” The stated purpose of the ESA, as amended, is, in part, “ * * * to provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved, to provide a program for the conservation of such endangered species and threatened species.” Some activities that are permissible under the Wilderness Act may affect the conservation of the Sierra Nevada bighorn sheep as indicated in our Special Management Considerations or Protection section. Therefore, the designation of critical habitat provides protections to the Sierra Nevada bighorn sheep that a wilderness designation does not.

(61)
Comment:
Manage “all suitable historic range” for Sierra Nevada bighorn sheep as events such as fire may create landscape changes that may encourage use in areas of historic range not currently suitable.

Our Response:
Please see our response to Comment 36.

Comments Related to Criteria and Methods

(62)
Comment:
Critical habitat should not be reduced to avoid potential difficulties with conflicting uses such as domestic sheep grazing in the northern units.

Our Response:
We have not reduced the amount of designated critical habitat in this final rule compared to the proposed rule due to potential conflicts with domestic sheep grazing. Please review the Criteria Used to Identify Critical Habitat section, as well as our response to Comment 39. The two herd units in the northern area, Twin Lakes and Green Creek, were not included in the critical habitat designation because they did not meet our criteria and are not considered essential to the conservation of the Sierra Nevada bighorn sheep. There is scientific uncertainty regarding whether these two herd units can support viable herds. There is a lack of historical evidence indicating numbers and uncertainty about connectivity between summer and winter ranges. Potential conflict with domestic sheep grazing was not a factor for not including these two areas in the designation.

(63)
Comment:
A concern was raised regarding the use of a road in proximity of critical habitat boundaries.

Our Response:
Existing roads and the lands under them are not considered critical habitat. Please also refer to our response to Comment 12.

Comments Related to Taxonomy

(64)
Comment:
The taxonomic revision should not be included in a rule on critical habitat.

Our Response:
While this rule is primarily to designate critical habitat for the Sierra Nevada bighorn sheep, the Service legally and appropriately determined to use this rulemaking process to address and correct related issues. The final listing rule published on January 3, 2000 (65 FR 20), inadvertently listed this entity as a DPS rather than as a subspecies. We sought to use our limited resources most efficiently by proposing the taxonomic revision to the Sierra Nevada bighorn sheep with our proposed critical habitat designation. We are revising the scientific name for the Sierra Nevada bighorn sheep from
Ovis canadensis californiana
to
Ovis canadensis sierrae
based on the current understanding of this subspecies' taxonomy.

(65)
Comment:
The taxonomic issue was not adequately addressed in the proposed rule.

Our Response:
We have provided a more thorough discussion of the genetic and morphometric studies supporting the distinctness of Sierra Nevada bighorn sheep as compared with other bighorn sheep populations in the Background section of this final rule.

(66)
Comment:
One commenter stated that the taxonomic question of whether the Sierra Nevada bighorn sheep is a unique subspecies should be answered before proceeding with the critical habitat designation.

Our Response:
The Sierra Nevada bighorn sheep, at listing, was thought to be part of a larger California bighorn sheep subspecies,
Ovis canadensis californiana
. However, based on the best scientific information available, genetic and morphologic research now indicates it should be classified as a separate subspecies,
O. c. sierrae
. Please see additional information provided in the Background section of this rule. We are aware of an unpublished preliminary analysis performed by the NDOA suggesting that Sierra Nevada bighorn sheep may be part of a continuous population of Nevada desert bighorn sheep. This analysis is based on microsatellite markers of samples collected from approximately 100 desert bighorn sheep from Nevada and California and one Sierra Nevada bighorn sheep from California. These results are preliminary and limited due to the single sample for Sierra Nevada bighorn sheep. This analysis has not been presented as a technical paper or published in a peer reviewed scientific publication. We cannot consider this as substantial new information at this time. Until further research is conducted either supporting or rejecting the suggestion that Sierra Nevada bighorn sheep is a part of a continuous population of Nevada desert bighorn sheep, we will use the best scientific information currently available indicating that Sierra Nevada bighorn sheep should be classified as a separate subspecies,
O. c. sierrae
.

(67)
Comment:
The animals found north of Mammoth Lakes should be declared Nelson bighorn or Nelson/Sierra Nevada bighorn sheep hybrids.

Our Response:
The commenter did not provide any data to support this statement, nor do we have any data to support this statement. Please refer to our response to Comment 66.

(68)
Comment:
Sierra Nevada bighorn sheep genetic material should be released to a third party so additional analyses can be conducted to determine whether this is a distinct subspecies.

Our Response:
To conduct research on a listed species, such as involving genetic material (considered a body part), a section 10(a)(1)(A) of the Act permit application must be submitted to the Service. The permitting process is described in 50 CFR 17.22, Permits for scientific purposes, enhancement of propagation or survival, or for incidental taking. Currently, only one entity has applied for and been issued a permit under section 10(a)(1)(A) of the Act for research activities involving Sierra Nevada bighorn sheep; this permit covers several individuals and institutions specifically listed in the permit.

Comments Related to Legal and Procedural Issues

(69)
Comment:
There is public frustration that a lawsuit is instigating designation of critical habitat at this time.

Our Response:
The Act requires designation of critical habitat at the time of listing unless not prudent or undeterminable. We are complying with a court approved settlement agreement to designate critical habitat for Sierra Nevada bighorn sheep. As indicated by the settlement agreement, we are required to submit to the
Federal Register
a final determination of critical habitat designation by July 17, 2008. Please see our Previous Federal Actions section of the rule for further details.

(70)
Comment:
A commenter was concerned that the final critical habitat designation could be expanded in the future.

Our Response:
Section 4(a)(3)(B) of the Act provides that critical habitat designations may, from time-to-time, be revised. A revision can propose an expansion or contraction of the boundaries. Any such revision would again be published in the
Federal Register
as a proposed rule with an opportunity for public comment before any such revision is made final.

(71)
Comment:
Why was the designation for critical habitat for the Sierra Nevada bighorn sheep not completed sooner?

Our Response:
Please refer to the Previous Federal Actions section of this final rule for additional information on this topic.

(72)
Comment:
The Service must designate sufficient critical habitat to support the “conservation” and “recovery” of the Sierra Nevada bighorn sheep, not just survival.

Our Response:
The process of designating critical habitat as described in the Act requires that the Service identify those lands on which are found the physical or biological features essential to the conservation of the species that may require special management considerations or protection, and the areas outside the current range of the species that are essential for its conservation. In identifying those lands, the Service must consider the recovery, as well as the survival, needs of the species. Once critical habitat has been designated, Federal agencies must consult with the Service under section 7(a)(2) of the Act to ensure that their actions will not destroy or adversely modify designated critical habitat or jeopardize the continued existence of the species. As noted in the Ninth Circuit's
Gifford Pinchot
decision, the jeopardy and adverse modification standards are distinct. Through the section 7(a)(2) consultation process, critical habitat designations provide recovery benefits to species by ensuring that Federal actions will not result in the destruction or adverse modification of designated critical habitat.

This final designation of critical habitat identifies units that are identical to those herd units that the recovery plan for the Sierra Nevada bighorn sheep identifies as necessary for recovery. Therefore, we believe we fully considered the recovery and survival needs of the Sierra Nevada bighorn sheep in this designation of critical habitat.

(73)
Comment:
The four herd units not included in the critical habitat likely qualify as a significant portion of the range for Sierra Nevada bighorn sheep. If Sierra Nevada bighorn sheep are recovered in the critical habitat, the subspecies would still be considered threatened or endangered in a significant portion of its range due to the four units not being included. The designation ignores recommendations of scientists that indicate that the Northern Recovery Unit is needed for recovery

and does not meet the recovery plan's objectives for reintroducing animals to vacant herd units or for increasing the number of herds by increasing geographic distribution and numbers.

Our Response:
The determination of a significant portion of a species range is not relevant to the designation of critical habitat. Rather, it applies in the context of listing or delisting a particular species; therefore, we do not consider what constitutes a significant portion of a species range in this final designation of critical habitat.

The recovery plan identifies four specific measurable criteria for delisting. Delisting Criterion B2 indicates that Sierra Nevada bighorn sheep must occupy 12 herd units. The recovery plan specifies 12 essential herd units that would likely contribute to recovery by receiving Sierra Nevada bighorn sheep through translocation or natural migration. The plan also identifies four non-essential herd units as locations that Sierra Nevada bighorn sheep could occupy based on historical Sierra Nevada bighorn sheep locations and habitat characteristics. However, the recovery plan did not identify these four herd units as essential to recovery because of uncertainty over whether viable populations could persist in these locations long-term. Three of the four non-essential herd units are currently unoccupied.

Because the critical habitat units and essential herd units have the same boundaries, we can achieve population size and distribution recovery goals for this species if we can establish and maintain populations within them. These critical habitat units are consistent with the recovery plan's goal of establishing new herds in currently unoccupied suitable habitat. Five of the critical habitat units are currently unoccupied, but we have designated them as critical habitat because these areas are essential to the establishment of herds that are necessary for recovery of the species.

Therefore, the recommendation for retaining the Northern Recovery Unit has been addressed through identification of the Mount Gibbs and Mount Warren essential herd units in the recovery plan and designation of critical habitat encompassing these two units.

(74)
Comment:
The rule should be suspended until the “required determinations” have been made.

Our Response:
As stated in the proposed rule, we indicated we would wait on the draft economic analysis to respond to various determinations. On February 5, 2008 (73 FR 6684), we published the notice of availability of our draft economic analysis, which also included our amended required determinations based on the draft economic analysis. This final rule contains our final required determinations which are based on the final economic analysis of this critical habitat designation. Please see the Required Determinations section for more information.

(75)
Comment:
The Service did not have resumes for the peer reviewers.

Our Response:
The Service solicits opinions of independent peer reviewers to ensure that our designations are based on “scientifically sound data, assumptions, and analyses.” Our longstanding practice does not require resumes to be submitted by peer reviewers.

(76)
Comment:
A commenter noted that one of the solicited peer reviewers was included in the literature citations for the proposed rule and questioned whether the peer reviewer had input during preparation of the proposed critical habitat.

Our Response:
The citation is for a document published by the peer reviewer in 2002. The peer reviewer did not have input during the preparation of the proposed critical habitat designation. Like the public, it is appropriate for a peer reviewer to provide input for a final critical habitat designation through comments on the proposed designation.

(77)
Comment:
An Environmental Impact Statement (EIS) should be required for any proposed project which may affect critical habitat.

Our Response:
Requiring an EIS is beyond the scope of a critical habitat designation. The Federal action agency will be responsible for the appropriate level of NEPA compliance with respect to any future proposed project. The level of such compliance would be determined by the action agency at that time.

(78)
Comment:
A few comments were received related to the two public meetings and one hearing held on the proposed critical habitat designation. While some people expressed appreciation of the Service's time and the opportunity to review maps, obtain hand out materials, and ask questions of Service employees one-on-one, others wanted a formal presentation with an opportunity to ask questions in a group setting. One commenter objected that public speaking time at the hearing was limited when few people had signed up to speak.

Our Response:
Although we have complied with the appropriate legal requirement, we appreciate this feedback and will continue to seek opportunities to share information on Sierra Nevada bighorn sheep with the public.

(79)
Comment:
Critical habitat boundary maps should have been overlaid on a topographic map.

Our Response:
Maps published in the
Federal Register
must be printed in a simplified format. In addition, due to the remote locations of the units, the number of landmarks available to assist with location descriptions is limited. The boundary descriptions in the Regulation Promulgation section of the final rule indicate the specific critical habitat unit boundaries.

(80)
Comment:
One commenter stated that the Service was moving too quickly and without having documents peer reviewed before citing them in the proposed critical habitat rule and DEA. The study by Clifford
et al.
(2007) was used as an example.

Our Response:
As indicated in the Critical Habitat section of this rule, we are legally required to use the best scientific and commercial data available when designating critical habitat. Under our Policy on Information Standards Under the Endangered Species Act and the Information Quality Act, we are able to use information available to us as publications in peer-reviewed scientific journals, agency documents, reports, etc. Many of these documents are not peer reviewed. Our use of Clifford
et al.
(2007) is not the basis for our designation of critical habitat for this subspecies; rather, we used it to provide information related to assessing the risk of and potential for a respiratory outbreak in Sierra Nevada bighorn sheep due to contact with domestic sheep. Addressing the presence of domestic sheep and grazing activities within critical habitat relates to the Special Management Considerations or Protection section. Please see our response to Comment 17.

Comments Related to Economic Issues

(81)
Comment:
It was requested that the Pine Creek Mine be excluded from the critical habitat designation for economic, national security, and safety issues.

Our Response:
When determining critical habitat boundaries for Sierra Nevada bighorn sheep, we made every effort to avoid including developed areas such as lands covered by buildings, paved areas, and other structures that lack PCEs for the Sierra Nevada bighorn sheep. The scale of the maps prepared under the parameters for publication within the Code of Federal Regulations may not reflect the exclusion of such developed areas. Any such features and the land under them

inadvertently left inside critical habitat boundaries shown on the maps of this final rule have been excluded by text in the final rule and are not designated as critical habitat. Therefore, Federal actions limited to these areas would not trigger section 7 consultation, unless they may affect the species or PCEs in adjacent critical habitat.

We consider activities such as new road construction, maintenance activities, road widening, and mining and construction of associated facilities as potentially impacting additional lands not within the footprint of existing facilities. These activities may affect the features that may need special management considerations or protection within designated critical habitat units. Federal agencies consult under section 7 of the Act to ensure that their proposed actions do not jeopardize the continued existence of the Sierra Nevada bighorn sheep or result in the destruction or adverse modification of its critical habitat. We have determined that undeveloped areas of the Pine Creek Mine are essential to the Sierra Nevada bighorn sheep as they contain the features essential to the conservation of the subspecies and meet the definition of critical habitat. Please see the Criteria Used To Identify Critical Habitat section for more information. One of our objectives is to provide consistency between critical habitat designation and the essential habitat indicated in the final recovery plan (Service 2007, p. 41).

The Secretary may exclude an area from critical habitat under section 4(b)(2) of the Act after taking into consideration the economic impact, the impact on national security, and any other relevant impact if he determines that the benefits of such exclusion outweigh the benefits of designating such area as critical habitat, unless he determines that the exclusion would result in the extinction of the species concerned.

We have considered this request by the commenter. We appreciate the commenter's willingness to continue to work with California Department of Game and Fish and the Service and provide access and use of mine roads, the helipad, and parking lots to assist with Sierra Nevada bighorn sheep monitoring activities. We are aware of the revegetation of tailings piles during the mine's idle years which have subsequently been used by Sierra Nevada bighorn sheep during winter months. We have previously consulted with the USFS on mining associated activities related to this mine and determined that those activities were not likely to adversely affect the Sierra Nevada bighorn sheep. Since critical habitat has not been previously proposed or designated for this species, it is anticipated that the USFS will initiate section 7 consultation as appropriate for any new activities proposed by the mine operators for which action agency authorization is required. These new activities may include construction or modification of escapeways and other safety facilities and surface stations and reworking of existing tailings piles. We will continue to work with the USFS and the permittee to address concerns related to the Sierra Nevada bighorn sheep during the section 7 consultation process as appropriate.

According to the final EA, post-designation baseline (due to listing) undiscounted costs for habitat management of which Pine Creek Mine is a portion is estimated at $14.8 million over the next 20 years (including $267,000 for impacts due to mining consultations). Post-designation incremental undiscounted costs (due to the designation of critical habitat) for mining consultations are estimated to be $14,640 over the next 20 years. These impacts are due to the predicted section 7 consultations by the USFS to address mining activities. Thus, costs are not considered to be disproportionate and we are not excluding these lands based on economic impacts.

The commenter also requested lands be excluded based on national security concerns. The National Defense Authorization Act for Fiscal Year 2004 (Pub. L. 108-136) amended section 4(a)(3)(B) of the Act (16 U.S.C. 1533(a)(3)(B)(i)) to state that the Secretary shall not designate as critical habitat any lands or other geographical areas owned or controlled by the Department of Defense, or designated for its use, that are subject to an integrated natural resource management plan (INRMP) prepared under section 101 of the Sikes Act (16 U.S.C. 670a), if the Secretary determines in writing that such plan provides a benefit to the species for which critical habitat is proposed for designation. The land in question is not Department of Defense land and does not have an INRMP. While the commenter provided information on use and application of tungsten in military applications, we do not believe that the designation of critical habitat will preclude the continued operation of the Pine Creek Mine. Additionally, a designation of critical habitat is not likely to preclude further development or exploration at the mine. Any future consultations under section 7 of the Act will include an analysis of adverse modification of critical habitat as well as a jeopardy analysis. We will continue to work with the USFS and permittee to address concerns related to the Sierra Nevada bighorn sheep during the section 7 consultation process as appropriate. Therefore, we are not excluding these lands based on national security concerns.

In conclusion, based on the record before us, we are not excluding those USFS lands on which the Pine Creek Mine occurs that meet the definition of critical habitat for Sierra Nevada bighorn sheep.

(82)
Comment:
The economic analysis should be conducted in a timely manner.

Our Response:
Pursuant to 50 CFR 424.19, we are not required to conduct an economic analysis at the time critical habitat is proposed. It would be ideal to provide the draft economic analysis with the proposal. However, due to the short time frame to complete the proposal, we were unable to do so. We published the proposed critical habitat designation on July 25, 2007 (72 FR 40956), invited public comment, and held one hearing and two informational meetings. We reopened the public comment period on the draft economic analysis and the proposed critical habitat designation for 30 days beginning on February 5, 2008 (73 FR 6684). We believe we provided adequate time for the public to provide comment on the proposed rule as well as the economic analysis consistent with the court-approved deadline for this determination. Comments received during the two open comment periods and during the public hearing and informational meetings were reviewed and incorporated into our decision making process as appropriate.

(83)
Comment:
The economic analysis for the critical habitat designation should show the cumulative impacts since listing the species.

Our Response:
In the economic analysis, costs were developed as pre-designation baseline, post-designation baseline, and post-designation incremental impacts. The pre-designation baseline and the post-designation baseline indicate the costs of the impacts of listing of the Sierra Nevada bighorn sheep. The post-designation incremental impacts are differentiated from the baseline as they are specifically related to the critical habitat designation. Thus, the economic analysis does provide a cumulative analysis of the economic impacts of actions taken to protect the Sierra Nevada bighorn sheep since its listing. Please refer to the final economic analysis for details.

Comments Related to the Draft Economic Analysis

Policy Issues

(84)
Comment:
One commenter states that the DEA does not state that while nearly half of the estimated economic impacts from proposed critical habitat are from the Mount Warren and Mount Gibbs habitat units, the northern herd units contain less than five percent of the total Sierra Nevada bighorn sheep herd population. The comment also states that incurring these impacts would be a futile, huge waste of money and that the DEA should draw the same conclusion.

Our Response:
As described in the framework of the economic analysis (Chapter 1), the purpose of the analysis is to estimate the economic impacts of Sierra Nevada bighorn sheep conservation measures as comprehensively as possible with publicly available data. A judgment concerning effectiveness or efficiency of the conservation measures that may be required by critical habitat designation is beyond the scope of the economic analysis.

(85)
Comment:
One commenter is concerned that the DEA does not calculate the costs of regulatory takings.

Our Response:
In accordance with E.O. 12630 (“Government Actions and Interference with Constitutionally Protected Private Property Rights”), we have analyzed the potential takings implications of designating critical habitat for the Sierra Nevada bighorn sheep in a takings implications assessment. Critical habitat designation does not affect landowner actions that do not require Federal funding or permits, nor does it preclude development of habitat conservation programs or issuance of incidental take permits to permit actions that do require Federal funding or permits to go forward. The takings implications assessment concludes that this designation of critical habitat for the Sierra Nevada bighorn sheep does not pose significant takings implications.

(86)
Comment:
A commenter stated that there was

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3AE8-16813. Public record. Not legal advice.