Sierra Nevada Bighorn Sheep Documents

2022-2023 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Fri, 03 Apr 2026 14:33:19 -0700

Annual summary of Sierra Nevada bighorn sheep 2022-23 - In 2022-23, most bighorn females (N = 43 collared individuals) died directly from snow-related causes, primarily avalanches or starvation. In addition, the extensive and persistent snowpack reduced the availability of snow-free winter ranges, increasing spatial overlap among bighorn, mule deer, and mountain lions and likely elevating predation risk (N = 9 collared females). Mortality was nearly range-wide, with one exception: the southernmost herd at Olancha, where the population increased during this period. Although large avalanches were observed on the flanks of Olancha Peak, this herd unit received significantly less snow than any of the others because it is the farthest south and the lowest elevation. Despite the severity of the winter, Sierra bighorn demonstrated notable resilience, with herds persisting under extreme environmental conditions.

A Strategy of Managing Predation on Sierra Nevada Bighorn Sheep

Thu, 29 Jan 2026 13:38:03 -0800

Predation Management, Sierra bighorn - Since the 1800s, Sierra Nevada bighorn sheep (Sierra bighorn; Ovis canadensis sierrae) have declined in abundance and distribution and are federally-listed as endangered under the Endangered Species Act of 1973, as amended. Predation by mountain lions (lions; Puma concolor) is one of the primary factors that threatens their recovery, and as a result, the Recovery Plan for the Sierra Nevada Bighorn Sheep (Recovery Plan; USFWS 2007) recommended the preparation and implementation of a management plan to protect Sierra bighorn from predation losses. This document describes the current state of knowledge regarding the impacts of lion predation on Sierra bighorn and delineates a strategy for mitigating these impacts.

REPORT TO THE FISH AND GAME COMMISSION FIVE-YEAR SPECIES REVIEW OF SIERRA NEVADA BIGHORN SHEEP (Ovis canadensis sierrae)

Tue, 05 Dec 2023 14:58:05 -0800

Sierra bighorn CESA Review - Sierra Nevada bighorn sheep (Ovis canadensis sierrae; hereafter Sierra bighorn) were listed as threatened under the California Endangered Species Act in 1971 and uplisted to endangered in 1999. The subspecies has been listed as endangered under the federal Endangered Species Act since 2000. Pursuant to Fish and Game Code section 2077, subdivision (a), the California Department of Fish and Wildlife (Department) has prepared this Five-Year Species Review to evaluate whether conditions that led to the original listing of Sierra bighorn are still present. This species review is based on the best scientific information currently available to the Department regarding each of the components listed under section 2072.3 of the Fish and Game Code, and Section 670.1, subdivisions (d) and (i)(1)(A), of Title 14 of the California Code of Regulations. In addition, this document contains a review of the identification of habitat that may be essential to the continued existence of the species, and the Department's recommendations for management activities and other recommendations for recovery of the species (Fish & G. Code, § 2077, subd. (a)).

2021-2022 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Thu, 17 Aug 2023 09:31:28 -0700

2021-22 Annual Report Sierra Nevada Bighorn Sheep Recovery Program - For the second consecutive year, the range-wide Sierra bighorn population increased, reaching 277 females. Although still short of the highest count of 316 females in 2016, the growth of most herds this year indicates a rebound from the heavy winters of 2016-17 and 2018-19. More specifically, we had the highest count ever at Williamson of 22 females and a count equal to the highest count at Bubbs of 17 females. Fortunately, this year was not as plagued with wildfire and smoky conditions as 2020. We were able to survey all 14 herds (Figure 2) in the summer, although technically the best count at Convict included both summer and winter data. Surveys included the first "good" quality count at Wheeler in 4 years. Unfortunately, the Olancha population declined for the first time since it was introduced in 2013, likely due to lower adult survival. Although not rebounding, the count of 17 females at Langley indicates this previous source herd has stopped declining. In addition to summer surveys, we were able to have both spring and fall bighorn captures. In the spring, we successfully translocated 7 bighorn from Baxter to Laurel including 4 females, 3 of which were pregnant. We were hoping these animals would make use of higher elevation (~10,000 ft) habitat within Laurel Creek, but as Laurel animals tend to do, some of the newly translocated bighorn have already wandered beyond the herd unit boundary. In the eastern Sierra region, we accounted for 55 mountain lions which exceeds the highest count from last year of 54. This includes the highest counts ever for three of the four count areas: northern, central, and Olancha. Additionally, 27 lions were captured and collared. These new collars helped to identify the 20 bighorn mortalities from lion predation, although 13 of these mortalities were from uncollared lions indicating more effort is needed to identify which lions are preying on bighorn. We documented two high elevation mountain lion kills, one in Wheeler near Meriam Peak at 3482 m (11,424 ft) in May and one in Langley at 3575 m (11,729 ft) in the Miter Basin in September. We successfully translocated a female lion along with her two 22-month-old offspring to the San Bernardino mountains to prevent them from killing additional Sierra bighorn. And finally, we published a rigorous evaluation of disease risk to Sierra bighorn. This new method considers the likelihood of Sierra bighorn movements when identifying potential overlap between Sierra bighorn and domestic sheep.

2020-2021 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Wed, 16 Aug 2023 12:32:45 -0700

2020-21 Annual Report Sierra Nevada Bighorn Sheep Recovery Program - A worldwide pandemic and catastrophic extreme wildfires in California appeared to be of no consequence to the Sierra Nevada bighorn sheep population, which grew slightly from 258 females in 2019 to 260 females in 2020. This is a welcome trend after the decline of the last three years, which included dramatic losses associated with the snowy winters of 2016-17 and 2018-19. Given that this was the second consecutive mild winter, the Sierra bighorn population growth rate was lower than expected; with survival at 86% it is low enough to prevent levels of growth desired for recovery. Recruitment based on observed lamb:ewe ratios was only slightly above average. With the exception of Olancha, most of the larger and moderate sized herds showed declines, while smaller herds tended to increase in size. The newly established Olancha herd continues to be a highlight, growing to 30 females this year. The Sierra Nevada Bighorn Sheep Recovery Program implemented measures to keep staff safe and healthy while continuing field and capture work. Due to smoky conditions, we were unable to perform summer surveys of Baxter, Olancha, and Williamson. However, we were able to get a good count at Olancha in the subsequent winter. In October, 56 animals were captured from 8 different herds, which will greatly increase our ability to monitor habitat use and vital rates. This was a particularly important capture as we were unable to capture in fall 2019 due to contract limitations. No bighorn translocations occurred.

2015-2016 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Mon, 17 Apr 2023 01:11:57 -0700

2015-2016 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - During the 2015-16 year, the Sierra Nevada bighorn sheep (Ovis canadensis sierrae; bighorn) population continued to increase. We estimated 320 adult and yearling females in the Sierra Nevada dispersed among 14 herds. These numbers surpass the downlisting goal of 305 females and the distribution includes occupancy in all required herd units. However, we are still working toward the more specific numeric goals for each area to fully meet the downlisting distribution requirements (U.S. Fish and Wildlife Service 2007). In the last three years, we have successfully repopulated four herd units through reintroduction. Field crews worked diligently to count adults, yearlings and lambs in 10 of the 14 herds. This year we captured and collared 62 bighorn from seven herds, which should improve our ability to track herd sizes and measure demographic rates. Although most herds increased in abundance, there was also a notable increase in the number of bighorn killed by mountain lions. Within herds, annual collared ewe survival averaged above 90% and estimated lamb survival ranged from 15-100%.

2016-17 Annual Report Sierra Nevada Bighorn Sheep Recovery Program Supplemental Materials

Mon, 17 Apr 2023 01:11:53 -0700

2016-2017 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - Appendix B. Table: Collar Details by Herd and Function for Sierra bighorn during May 2016 – June 2017. Identification of each animal wearing a collar by April 30, 2017. Collar status is functional VHF (fVHF), functional GPS (fGPS), non-functional VHF (non fVHF), non-functional GPS (non fGPS). VHF_old are animals who currently have a functional VHF but the VHF is >5 years old. Recent Morts are animals we believe are dead but have not yet investigated or recovered. fMark New are the functional collars we project to have for that herd for the next animal year (fVHF + fGPS – oldVHF -Recent Morts). MC is the minimum count from animal year 2016.

2016-17 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Mon, 17 Apr 2023 01:11:51 -0700

2016-2017 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - This report covers monitoring, management, and conservation activities carried out between May 1, 2016 and April 30, 2017 by the California Department of Fish and Wildlife’s (CDFW) Sierra Nevada Bighorn Sheep Recovery Program. The 2016-17 year was the second wettest year on record for the central Sierra Nevada, which received 73 inches of precipitation (>600 inches of snow in some locations). Although the precipitation was a welcome relief from four years of drought, the impact on Sierra Nevada bighorn sheep (Ovis canadensis sierrae; hereafter bighorn) was severe. Multiple lines of evidence support our estimate that more than 100 females died this winter, or roughly 30% of the known population of females. While more severe than recent big winters, the year-end counts including recruitment only indicate a net loss of 56 ewes, a testament to the resilience of Sierra bighorn. Although most of these mortalities were related to big winter conditions (e.g., caused by malnutrition or avalanche), this includes 17 lion kills, most of which occurred at Langley. Individual collared female mortality varied from 0-80% between herds during the winter and annual collared female survival rates varied by herd from 33-90%. We also documented 9 uncollared and 48 collared ram mortalities that included 8 of the 9 rams translocated during the fall. This is the greatest loss of individuals, as well as the greatest range-wide proportional loss, the Sierra Nevada Bighorn Sheep Recovery Program (hereafter Recovery Program) has documented in a single year. Encouragingly, Sierra bighorn are still distributed across 14 herds, but some herds (Laurel and Convict) are small (<7 females) and may require augmentation to persist. Overall, these losses will extend the timeline for achieving downlisting goals.

Endangered Sierra Nevada Bighorn Sheep Translocation A First Time Volunteer’s Account

Sun, 16 Apr 2023 18:39:36 -0700

Volunteer Testimonial on working with Sierra Nevada Bighorn Sheep - Volunteer testimonial about working with and viewing Sierra Nevada bighorn sheep

Animal Movements Map -MountLangley_Male_S427 pdf

Sun, 16 Apr 2023 17:48:33 -0700

Animal Movements Map -MountLangley_Male_S427 pdf - Animal Movements Mount Langley pdf format

Animal Movements Map - MountLangley_Female_S425 pdf

Sun, 16 Apr 2023 17:48:31 -0700

Animal Movements Map - MountLangley_Female_S425 pdf - Animal Movements Mount Langley pdf format

Animal Movements Map - MountWilliamson_Male_S113 pdf

Sun, 16 Apr 2023 17:48:28 -0700

Animal Movements Map - MountWilliamson_Male_S113 pdf - Animal Movements Map Mount Williamson pdf format

Animal Movements Map - MountWilliamson_Female_S114 pdf

Sun, 16 Apr 2023 17:48:26 -0700

Animal Movements Map - MountWilliamson_Female_S114 pdf - Animal Movements Mount Williamson pdf format

Animal Movements Map - BubbsCreek_Male_S249 pdf

Sun, 16 Apr 2023 17:48:24 -0700

Animal Movements Map - BubbsCreek_Male_S249 pdf - Animal Movements Bubbs Creek pdf format

Animal Movements Map - BubbsCreek_Female_S315 pdf

Sun, 16 Apr 2023 17:48:20 -0700

Animal Movements Map - BubbsCreek_Female_S315 pdf - Animal Movements Bubbs Creek pdf format

Animal Movements Map - LaurelCreek_Female_S376 pdf

Sun, 16 Apr 2023 17:48:17 -0700

Animal Movements Map - LaurelCreek_Female_S376 pdf - Animal Movements Map Laurel Creek pdf format

Animal Movements Map - MountBaxter_Male_S202 pdf

Sun, 16 Apr 2023 17:48:14 -0700

Animal Movements Map - MountBaxter_Male_S202 pdf - Animal Movements Map Mount Baxter pdf format

Sierra Nevada Bighorn Sheep Citizen Science

Sun, 16 Apr 2023 17:44:11 -0700

Sierra Nevada Bighorn Sheep Citizen Science - guide to help do age / sex classification of Sierra Nevada Bighorn Sheep

2014 Addendum to the Translocation Plan for SNBS

Sun, 16 Apr 2023 15:47:19 -0700

2014 Addendum to the Translocation Plan for SNBS - Sierra Nevada bighorn sheep (hereafter Sierra bighorn) are a subspecies of wild sheep native to the mountain range for which they are named. While the population, first listed as federally endangered in 1999, has grown from approximately 100 at the time of listing to 500 in recent years, the current size and geographic distribution makes the population susceptible to factors such as disease, predation, and weather. Recovery goals stipulate that 305 adult and yearling females be distributed among 12 geographic areas referred to as herd units (USFWS 2007). Currently, 9 of these 12 herd units are occupied. Translocations to reoccupy historic habitat are integral to achieving a distribution of Sierra bighorn that will ensure long-term viability of the subspecies (USFWS 2007). This addendum to the Translocation Plan for Sierra Nevada Bighorn Sheep (Few et al. 2013; hereafter Translocation Plan) evaluates the conservation potential of a reintroduction to the Big Arroyo herd unit in the Kern recovery unit and an augmentation to the recently reintroduced herd at Olancha Peak.

Translocation Plan for Sierra Nevada Bighorn Sheep

Sun, 16 Apr 2023 15:47:16 -0700

Translocation Plan for Sierra Nevada Bighorn Sheep - Translocations are integral to achieving a distribution of Sierra bighorn that will ensure long-term viability of the population (USFWS 2007). This plan considers many concerns: logistics, habitat, predation, population viability of source and reintroduced herds, genetic variability, disease, and recent capture activity. Translocations planned for spring 2013 include a reintroduction to the currently unoccupied herd unit at Olancha Peak and augmentations to increase genetic variability at Mt. Gibbs. Additional augmentations to increase the size of herds at Convict Creek and Mt. Warren may occur if logistical constraints allow.

2013-2014 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program

Sun, 16 Apr 2023 15:38:29 -0700

2013-2014 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - This report documents conservation and monitoring activities conducted during May 1 2013-April 30 2014 by the California Department of Fish and Wildlife’s (CDFW’s) Sierra Nevada Bighorn Sheep Recovery Program (the Recovery Program). Since its inception in 1999, the Recovery Program has worked to restore state- and federally-endangered Sierra Nevada bighorn sheep (Sierra bighorn) through science-oriented adaptive management. We monitor for survival and the presence of disease, track bighorn distribution, abundance, and vital rates, and conduct captures and translocations to deploy radio collars and restore populations to historic ranges. The Recovery Plan for the Sierra Nevada Bighorn Sheep(hereafter the Recovery Plan, USFWS 2007) specifies downlisting and delisting goals that include the occupation of 12 herd units with a minimum total of 305 females. At the end of this reporting period we estimate that the Sierra bighorn population contained at least 258 females in 11 herd units, 10 of which are listed as recovery goals (Figure 1). In March 2014 we carried out the first reoccupation within the Kern Recovery Unit by reintroducing bighorn to the Big Arroyo herd unit in Sequoia National Park. With continued conservation and management, Sierra bighorn may achieve recovery goals in less than a decade.

2012-2013 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program

Sun, 16 Apr 2023 15:38:27 -0700

2012-2013 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - This report documents conservation and monitoring activities carried out between May 1 2012 and April 30 2013 by the California Department of Fish and Wildlife’s (CDFW’s) Sierra Nevada Bighorn Sheep Recovery Program (the Recovery Program). The Recovery Program is charged with restoring state- and federally-endangered Sierra Nevada bighorn sheep (Sierra bighorn) in accordance with the delisting goals specified in the Recovery Plan (USFWS 2007). These goals recommend the occupation of 12 herd units with a total of 305 females. The Recovery Program regularly monitors bighorn distribution, abundance, and demographic rates. Our efforts also include habitat enhancement, monitoring for causes of mortality and the presence of disease, captures to deploy radio collars, and translocations to restore populations to historic ranges and to augment existing herds. At the end of the 2012 survey season we estimate that the Sierra bighorn population comprised at least 217 females in 10 herd units, including a newly-reintroduced population at Olancha Peak. If the trends observed over the last decade continue, Sierra bighorn may reach recovery goals within a decade.

Annual report 2011-2012 Sierra Nevada bighorn sheep recovery program May 2011 - April 2012

Sun, 16 Apr 2023 13:55:34 -0700

Annual summary of Sierra Nevada bighorn sheep program 2011-2012 - This report documents conservation and monitoring activities carried out by the Sierra Nevada Bighorn Sheep Recovery Program between May 1, 2011 and April 30, 2012. The purpose of the Recovery Program is to conserve and restore state and federally endangered Sierra Nevada bighorn sheep to reach delisting goals specified in the Recovery Plan in as timely a manner as possible. When these bighorn were listed as endangered in 1999 there were about 125 bighorn sheep throughout the Sierra Nevada. At the end of this reporting period we estimate there are more than 480 bighorn using habitat from the Cottonwood Lakes Basin in the Mt. Langley herd unit to Virginia Lakes in the Mt. Warren herd unit. While Sierra bighorn numbers have grown in recent years, these bighorn remain the rarest mountain sheep in North America. Progress towards delisting is measured both in the geographic distribution of Sierra bighorn and in the number of females in each of 4 recovery units. Currently, 8 of 12 herd units necessary for delisting are occupied. Minimum counts over the last year documented 191 females, but additional information suggests that there are at least 220 ewes. With continued support for conservation activities, Sierra bighorn are poised to reach the recovery goal of 305 females in 12 herd units within a decade.

Risk-sensitive allocation in seasonal dynamics of fat and protein reserves in a long-lived mammal

Sun, 16 Apr 2023 12:24:54 -0700

Risk-sensitive allocation in seasonal dynamics of fat and protein reserves in a long-lived mammal - 1. Body reserves of numerous taxa follow seasonal rhythms that are a function of temporal patterns in food availability and life-history events; however, tests of the theory underlying the allocation of somatic reserves for long-lived organisms are rare, especially for free-ranging mammals. We evaluated the hypothesis that allocation of somatic reserves to survival (i.e., metabolic processes) and reproduction should be sensitive to current nutritional state relative to seasonal thresholds in those reserves. 2. Our goal was to reveal the linkages between nutrition and life-history traits to understand how long-lived, iteroparous organisms balance the allocation of somatic reserves to reproduction, while retaining reserves as insurance for survival in unpredictable environments. Our evaluation was based on seasonal dynamics in fat (measured as ingesta-free body fat; IFBFat) and protein reserves (measured as ingesta-free, fat-free body mass; IFFFBMass) of 136 female mule deer (Odocoileus hemionus) over 8 years. 3. Although mean changes in fat and protein reserves were positive over summer and negative over winter, accretion and catabolism of those reserves was not consistent among individuals. Over winter, both lipid and protein stores available in autumn were catabolized in proportion to their availability above a post-winter threshold (58% IFBFat, 33 kg IFFFBMass); however, lean body tissue was spared at the expense of lipid reserves. 4. Female deer mostly synthesized lean body tissue over summer and committed post-winter fat reserves to reproduction relative to their availability above an autumn threshold (>86% IFBFat), which was lowered by 28 percentage points (pp) for each additional young recruited. Mothers reduced their autumn fat threshold to secure current reproductive investment and, thereby, endured a cost of reproduction at the expense of fat accumulation. 5. Allocation of somatic reserves occurred in a risk-sensitive framework; females allocated reserves relative to their availability above seasonal thresholds. In contrast to current notions of summer accretion and winter catabolism of body reserves, some individuals deposited reserves over winter and catabolized reserves over summer, mainly because regulation of individual condition was state-dependent. Consequently, behavior and life-history strategies may be as much a function of nutritional contributions of the previous season as of the current one.

Top-down versus bottom-up forcing: evidence from mountain lions and mule deer

Sun, 16 Apr 2023 12:13:48 -0700

Top-down versus bottom-up forcing: evidence from mountain lions and mule deer - We studied mountain lions (Puma concolor) and mule deer (Odocoileus hemionus) inhabiting a Great Basin ecosystem in Round Valley, California, to make inferences concerning predator–prey dynamics. Our purpose was to evaluate the relative role of top-down and bottom-up forcing on mule deer in this multiple-predator, multiple-prey system. We identified a period of decline (by 83%) of mule deer (1984–1990), and then a period of slow but steady increase (1991–1998). For mule deer, bitterbrush (Purshia tridentata) in diets, per capita availability of bitterbrush, kidney fat indexes, fetal rates (young per adult female), fetal weights, and survivorship of adults and young indicated that the period of decline was typical of a deer population near or above the carrying capacity (K) of its environment. Numbers of mountain lions also declined, but with a long time lag. The period of increase was typified by deer displaying life-history characteristics of a population below K, yet the finite rate of growth (lambda = 1.10) remained below what would be expected for a population rebounding rapidly toward K (lambda = 1.15–1.21) in the absence of limiting factors. Life-history characteristics were consistent with the mule deer population being regulated by bottom-up forcing through environmental effects on forage availability relative to population density; however, predation, mostly by mountain lions, was likely additive during the period of increase and thus, top-down forcing slowed but did not prevent population growth of mule deer. These outcomes indicate that resource availability (bottom-up processes) has an ever-present effect on dynamics of herbivore populations, but that the relationship can be altered by top-down effects. Indeed, top-down and bottom-up forces can act on populations simultaneously and, thus, should not be viewed as a stark dichotomy.

Notice of Determination(NOD): US Forest Service Environmental Assessment for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:46 -0700

CEQA for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - In lieu of preparing its own Mitigated Negative Declaration, the Department of Fish and Game (CDFG), Inland Deserts Region, acting as lead agency under the California Environmental Quality Act (CEQA), intends to use the Environmental Assessment (EA)/Findings of No Significant Impact (FONSI), prepared by the Inyo National Forest, for a project that authorizes CDFG to land a helicopter within the wilderness areas to capture endangered Sierra Nevada bighorn sheep for population monitoring, research, and translocations.

Notice of Intent (NOI): Inyo National Forest Environmental Assessment - Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:44 -0700

Findings of No Significant Impact (FONSI): Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:36 -0700

Findings of No Significant Impact (FONSI): Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - Findings of No Significant Impact - Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Environmental Assessment (EA) - Appendix D: Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:35 -0700

USFS Environmental Assessment Appendix D for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - Appendix D - Proposed Number of SNBS Captures and Helicopter Landings per Year Over a 10-year period.

Environmental Assessment (EA) - Appendix C: Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:33 -0700

USFS Environmental Assessment Appendix C for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - Appendix C - Need and Justification for the Use of Helicopter Net-Guns to Capture Sierra Nevada Bighorn Sheep

Environmental Assessment (EA) - Appendix B: Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:32 -0700

USFS Environmental Assessment Appendix B for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - Appendix B - Sierra Nevada Bighorn Sheep Managements Activities Conducted by the California Department of Fish and Game

Environmental Assessment (EA) - Appendix A: Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:30 -0700

USFS Environmental Assessment Appendix A for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - Appendix A - Response to Comments for capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Environmental Assessment (EA): Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas

Sun, 16 Apr 2023 12:13:28 -0700

USFS Environmental Assessment for Capturing Sierra Nevada Bighorn Sheep Within Portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wilderness Areas - The Inyo National Forest proposes to authorize helicopter landings by the California Department of Fish and Game (CDFG) within designated wilderness areas for the purposes of population monitoring and translocation of endangered Sierra Nevada bighorn sheep (SNBS). This action is needed to meet recovery actions established in the Sierra Nevada Bighorn Sheep Recovery Plan (hereafter, Recovery Plan, USDI 2007a). Recovery of this unique subspecies depends on gathering information on habitat use and vital rates that determine population dynamics through the placement of Very High Frequency (VHF) and Global Positioning System (GPS) collars on individual bighorn sheep, as well as augmenting populations of bighorn sheep and introducing animals into currently unoccupied portions of their historic range. These actions require the use of a helicopter in capturing and transport efforts. The project area is located within portions of the Ansel Adams, Hoover, John Muir, Golden Trout, and South Sierra Wildernesses on the Mono Lake, Mammoth, White Mountain, and Mt. Whitney Ranger Districts, Inyo National Forest, California. Management of SNBS was delegated to the California Department of Fish and Game by the U.S. Fish and Wildlife Service. On the Inyo National Forest, the majority (80% or approx. 275,210 acres) of the recovery area for SNBS is within designated wilderness areas and is not accessible by road. Wilderness is designated by Congress and management of these areas differs from the general forest portions of National Forest System Lands. Wilderness is a unique and vital resource; offering opportunities for primitive recreation, for scientific and educational uses, as a benchmark for ecological studies, and for the preservation of historical and natural features.

Recommedations for domestic sheep and goat management in wild sheep habitat

Sun, 16 Apr 2023 12:10:26 -0700

Recommedations for domestic sheep and goat management in wild sheep habitat - Although the risk of disease transmission from domestic sheep or goats to wild sheep is widely recognized, a unified set of management recommendations for minimizing this risk has not been adopted by responsible agencies. These Western Association of Fish and Wildlife Agencies (WAFWA)recommendations were produced to help state, provincial, and territorial wild sheep managers, federal/crown land management agencies, private landowners and others take appropriate steps to eliminate range overlap, and thereby, reduce opportunities for transmission of pathogens to wild sheep. Transmission of Mannheimia haemolytica from domestic sheep to bighorn sheep was irrefutably demonstrated by Lawrence et al. (2010) and provides justification sufficient for preventing range overlap and potential association of domestic sheep and goats with wild sheep. The higher the conservation value of a wild sheep population (e.g., federally or state listed, “sensitive species” status, native herds, transplant source stock, herds in areas with no history of domestic livestock presence), the more aggressive and comprehensive wild sheep and domestic sheep or goat separation management strategies should be.

Evaluating apparent competition in limiting the recovery of an endangered ungulate

Sun, 16 Apr 2023 12:09:53 -0700

Evaluating apparent competition in limiting the recovery of an endangered ungulate - Predation can disproportionately affect endangered prey populations when generalist predators are numerically linked to more abundant primary prey. Apparent competition, the term for this phenomenon, has been increasingly implicated in the declines of endangered prey populations. We examined the potential for apparent competition to limit the recovery of Sierra Nevada bighorn sheep (Ovis canadensis sierrae), an endangered subspecies under the US Endangered Species Act. Using a combination of location, demographic, and habitat data, we assessed whether cougar (Puma concolor) predation on endangered bighorn sheep was a consequence of their winter range overlap with abundant mule deer (Odocoileus hemionus). Consistent with the apparent competition hypothesis, bighorn sheep populations with higher spatial overlap with deer exhibited higher rates of cougar predation which had additive effects on adult survival. Bighorn sheep killed by cougars were primarily located within deer winter ranges, even though those areas constituted only a portion of the bighorn sheep winter ranges. We suspect that variation in sympatry between bighorn sheep and deer populations was largely driven by differences in habitat selection among bighorn sheep herds. Indeed, bighorn sheep herds that experienced the highest rates of predation and the greatest spatial overlap with deer also exhibited the strongest selection for low elevation habitat. Although predator-mediated apparent competition may limit some populations of bighorn sheep, it is not the primary factor limiting all populations, suggesting that the dynamics of different herds are highly idiosyncratic. Management plans for endangered species should consider the spatial distributions of key competitors and predators to reduce the potential for apparent competition to hijack conservation success.

Disease, Population Viability, and Recovery of Endangered Sierra Nevada Bighorn Sheep

Sun, 16 Apr 2023 11:35:16 -0700

Evaluate potential impact of disease on demographic rates and species persistence - Sierra Nevada bighorn sheep (Ovis canadensis sierrae) experienced a severe population decline after European settlement from which they have never recovered; this subspecies was listed as endangered under the United States Endangered Species Act (ESA) in 1999. Recovery of a listed species is accomplished via federally mandated recovery plans with specific population goals. Our main objective was to evaluate the potential impact of disease on the probability of meeting specific population size and persistence goals, as outlined in the Sierra Nevada bighorn sheep recovery plan. We also sought to heuristically evaluate the efficacy of management strategies aimed at reducing disease risk to or impact on modeled bighorn populations. To do this, we constructed a stochastic population projection model incorporating disease dynamics for 3 populations (Langley, Mono, Wheeler) based on data collected from 1980 to 2007. We modeled the dynamics of female bighorns in 4 age classes (lamb, yearling, adult, senescent) under 2 disease scenarios: 5% lower survival across the latter 3 age classes and persistent 65%lower lamb survival (i.e., mild) or 65% reduced survival across all age classes followed by persistent 65% lower lamb survival (i.e., severe). We simulated management strategies designed to mitigate disease risk: reducing the probability of a disease outbreak (to represent a strategy like domestic sheep grazing management) and reducing mortality rate (to represent a strategy that improved survival in the face of introduced disease). Results from our projection model indicated that management strategies need to be population specific. The population with the highest growth rate (^l; Langley; ^l ¼ 1.13) was more robust to the effects of disease. By contrast, the population with the lowest growth rate (Mono; ^l ¼ 1.00) would require management intervention beyond disease management alone, and the population with a moderate growth rate (Wheeler; ^l ¼ 1.07) would require management sufficient to prevent severe disease outbreaks. Because severe outbreaks increased adult mortality, disease can directly reduce the probability of meeting recovery plan goals. Although mild disease outbreaks had minimal direct effects on the populations, they reduced recruitment and the number of individuals available for translocation to other populations, which can indirectly reduce the probability of meeting overall, range-wide minimum population size goals. Based on simulation results, we recommend reducing the probability of outbreak by continuing efforts to manage high-risk (i.e., spatially close) allotments through restricted grazing regimes and stray management to ensure recovery for Wheeler and Mono. Managing bighorn and domestic sheep for geographic separation until Sierra Nevada bighorn sheep achieve recovery objectives would enhance the likelihood of population recovery.

2019-20 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Tue, 17 Jan 2023 11:50:05 -0800

2019-20 Annual Report Sierra Nevada Bighorn Sheep Recovery Program - In the last three years, there has been an unexpected decline in the Sierra bighorn population, which is currently estimated to be just under 500 with 249 females, 81 lambs, and 166 males. During the California drought of 2012-2016, the range-wide population increased from 202 to 314 females, and Sierra bighorn experienced low levels of lion predation and mild winters. Then came the nearly record-breaking winter of 2016-17 during which ~100 females died, or 30% of all known females (not including lambs). Another heavy winter quickly followed in 2018-19 during which ~75 females died, or 25% of all known females. Most of these losses were associated with deep snow conditions, but there was also extreme lion predation at Langley (Gammons et al. 2021), which had previously been one of the largest source herds. These major losses have delayed downlisting for at least another five years, and perhaps longer if we have more heavy snow winters or extreme predation. These declines have not only limited our capacity to augment new herds, which are just getting established, but have also reduced some source herds and other herds to concerningly low levels. Fortunately, 2019 was a relatively mild winter and Sierra bighorn experienced average levels of survival and fecundity. This spring we successfully translocated six females from Wheeler into Warren (Figure 1), because the Warren population had declined to a single female and three males. Olancha, which was reintroduced in 2013, is now the fourth largest of all herds and has been the most productive of the recently reintroduced herds. This year we greatly increased our mountain lion monitoring efforts, including adding a count zone associated with Olancha. We had the highest mountain lion count for the region (N=50). Additionally, we successfully translocated a lion that was known to prey upon Sierra bighorn out of Warren, one of the more sensitive herds. The Sierra Nevada Bighorn Sheep Recovery Program is focused on reducing any further losses through mountain lion management and bolstering any small herds through translocation when source herds allow.

Defense of One Twin Calf against Wolves, Canis lupus, by a Female Moose, Alces alces

Fri, 06 Jan 2023 14:13:47 -0800

Wolf, Canis lupus, Moose, Alces alces, calf, predation, predator avoidance, behavior, Alaska - Three Wolves (Canis lupus) were observed attacking an adult cow Moose (Alces alces) with neonatal twins on the Copper River Delta, Alaska, during summer 1993. The cow successfully defended one calf from predation but the other was killed in a stream after fleeing from the cow. The cow and the remaining surviving calf moved to the stream and established a superior defensive position and both survived the Wolf attack.

Wolf, Canis lupus, predation on dusky Canada geese, Branta canadensis occidentalis

Fri, 06 Jan 2023 14:10:05 -0800

wolves, dusky Canada geese, predation, alternate prey, Alaska - On two occasions on the Copper River Delta, Alaska, radio-collared Wolves (Canis lupus) were observed locating and consuming Dusky Canada Goose eggs. On a third occasion, a pair of Wolves killed three geese. Non-mammalian Wolf prey on the Copper River Delta is abundant relative to other areas. Although geese may be less profitable than ungulate prey, there is less risk associated with their capture and the availability of such alternate prey may lead to decreased Wolf predation on Moose at this site.

2022 Status of Bighorn Sheep Herds that Utilize Yosemite National Park

Thu, 17 Nov 2022 14:10:17 -0800

Annual summary of Sierra Nevada bighorn sheep in Yosemite 2022 - This report presents data on Sierra Nevada bighorn sheep (SNBS) herds that use habitat within Yosemite National Park (YNP). SNBS are a unique subspecies of bighorn sheep (Ovis canadensis sierra) that are classified as endangered at state and federal levels (U. S. Fish and Wildlife Service 2007). They were first re-established in the YNP region in 1986 via a translocation of native SNBS from the southern Sierra to Lee Vining Canyon to initiate the Mount Warren herd. In the early fall of 1986, three of the ewes released that year and two lambs born to them in Lee Vining Canyon moved south to initiate the Mount Gibbs herd. In the spring of 2015, the Cathedral Range herd was initiated with the release of ten ewes and three rams near Washburn Lake in Yosemite National Park. Those three herd units constitute the current populations within the northern recovery unit (NRU) – one of 4 recovery units identified in the recovery plan for SNBS (U. S. Fish and Wildlife Service 2007). In the spring of 2015 the Mount Gibbs herd was expanded geographically with the release of 5 ewes in the Alger Lakes basin which created a ewe group that has remained a geographically separate unit (deme) within the Mount Gibbs herd, the population dynamics of which have been tracked separately from the rest of the Mount Gibbs herd.

2018-19 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Thu, 28 Apr 2022 08:42:43 -0700

2018-2019 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - In 2018-19, there was large and long-lasting snowpack in the Sierra Nevada. We estimated that 72 Sierra bighorn females died, representing 25% of the population. Snow-caused mortality in the form of starvation and avalanche was the most common cause of death, causing 39% of collared female mortalities, while lion predation caused 12% of collared female mortalities this year. Despite these losses, no herd units were extirpated. Winter impacts were highly variable between herds, with little mortality in the Olancha herd but the largest proportional impacts in Bubbs, Big Arroyo, Warren, and Cathedral. The largest numeric losses were in Gibbs and Sawmill. Bighorn movements documented this year demonstrated continued connectivity between herds as well as expansion within herd units. Specifically, individuals moved between the Baxter, Williamson, and Langley herds, as well as between Gibbs and Cathedral. At Convict, animals have begun using the north side of McGee Creek, and in the Big Arroyo, at least one individual crossed to the east side of the Kern River. We documented a minimum of 37 lions in the eastern Sierra region, including 25 within the three count zones associated with Sierra bighorn. This is the greatest number of lions ever documented in these zones, although predation levels were not extreme this year. We define “extreme” predation levels as being above the 90th percentile or 11.4% within a single herd. Lions did kill a minimum of 13 Sierra bighorn across six herd units. Male lion L147 killed at least four of these animals and traveled through at least seven Sierra bighorn herds. Lion predation has persisted in the Langley herd, and its population continues to decline. In 2018, a new climbing guidebook was published that focused on the Pine Creek region, which is an important lambing area for the Wheeler Ridge herd. Climbing use in Pine Creek has notably increased since 2010.

Predation impedes recovery of Sierra Nevada bighorn sheep

Mon, 23 Aug 2021 09:54:27 -0700

Predation impedes recovery of Sierra Nevada bighorn sheep - Translocation of animals into formerly occupied habitat is a key element of the recovery plan for Sierra Nevada bighorn sheep, which are state (California) and federally listed as endangered. However, implementing Sierra bighorn translocations is a significant conservation challenge because of the small size of the extant population and the limited number of herds available to donate translocation stock. One such herd, the Mt. Langley herd, recently became unusable as a translocation source following a substantial population decline. At the time of listing in 1999, predation by mountain lions (Puma concolor; hereafter lion) was considered a primary threat to Sierra bighorn, and since then lion predation may have continued to limit the ability of source herds to provide translocation stock. We evaluated the relationship between lion predation and ewe survival rates within three source herds of the Southern Recovery Unit, compared lion abundance and ewe survival among years of varying predation levels, provided a range of estimated times for the Mt. Langley herd to recover to its former status as a translocation source, and determined if the rates lions have been removed to mitigate Sierra bighorn predation exceeded sustainable harvest guidelines. We found compelling evidence that lion predation has impeded the recovery of Sierra bighorn by reducing survival rates of adult ewes (and consequently, population growth) and by preying upon individuals that could have otherwise been translocated. Ewe survival was poor during years of extreme predation but even during years of typical predation, survival rates were below a level needed to ensure population growth, indicating that years with little or no lion predation may be necessary for the population to grow and meet recovery goals. Because the intensity of predation was related to lion abundance, monitoring lion populations could provide managers with advance warning of periods of extreme predation. We found that following a period of particularly extreme predation, the Mt. Langley herd decreased in abundance far below the threshold needed to be considered a source of translocation stock, resulting in the loss of approximately 25% of the recovery program’s capacity for translocations. It is unclear how many years it will take for this herd to recover, but management actions to reduce lion predation are likely needed for this herd to grow to a size that can afford to donate individuals to translocation efforts in the near future, even when optimistic growth rates are assumed. We found that lion removal may also be needed to prevent predation from leading to Sierra bighorn population decline.

2017-18 Annual Report Sierra Nevada Bighorn Sheep Recovery Program

Wed, 07 Apr 2021 14:15:38 -0700

2017-2018 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - Sierra Nevada bighorn sheep (Ovis canadensis sierrae, hereafter Sierra bighorn) survival rebounded quickly from the record lows during the heavy snow winter of 2016-17. Both milder winter conditions this year (2017-18, Figure 1) and last year’s mountain lion (Puma concolor, hereafter lion) management likely influenced survival rates. Although survival has returned to more average values, the overall population of female bighorn is taking longer to recover. We found a slight decrease in the total number of females this year, possibly due to poor recruitment during the 2016-17 winter; the total population is now 552 animals, which includes 266 adult and yearling females. While some of the herds remain small (female N<5), there was no loss of herd unit occupation. Bighorn movements documented this year demonstrate connectivity between herds (Mt. Baxter and Mt. Williamson as well as Mt. Gibbs and Cathedral Range). Along with our robust capture and monitoring program for Sierra bighorn, we expanded our efforts to focus on their main predator, lions. We documented a minimum of 19 lions in eastern Sierra Nevada count zones, which is the greatest number of individuals ever counted for this area. Research published on Sierra bighorn this year included analyses of migration, female survival, and the effects of nutrition on ram horn size. The highlight of our public outreach for the year was ‘Project Bighorn,’ developed by members of Girl Scout Troop 580 which included the development of an original game, internet quizzes, and a Sierra bighorn rap song.

Endangered and threatened wildlife and plants; emergency rule to list the Sierra Nevada distinct population segment of California bighorn sheep as endangered

Thu, 03 Oct 2019 11:40:51 -0700

Emergency ESA Listing Sierra Bighorn Sheep 1999 - Emergency Listing Sierra Bighorn Sheep 1999

Endangered and threatened wildlife and plants; final rule to list the Sierra Nevada distinct population segment of the California bighorn sheep as endangered

Thu, 03 Oct 2019 11:40:31 -0700

Final ESAListing Sierra Bighorn Sheep 2000 - Final ESAListing Sierra Bighorn Sheep 2000

Life on the Edge: Risk of Predation Drives Selection of Habitat and Survival of Neonates in Endangered Sierra Nevada Bighorn Sheep

Thu, 16 May 2019 09:22:59 -0700

Risk of Predation Drives Selection of Habitat and Survival of Neonates in Endangered Sierra Nevada Bighorn Sheep - Long-term viability of endangered populations requires development of effective management strategies that target the population vital rate with the highest potential to influence population trajectories. When adult survival is high and stable, juvenile recruitment is the vital rate with the greatest potential to improve population trajectories. For my thesis I examined how lactating Sierra Nevada Bighorn sheep (Ovis Canadensis sierra) balance forage and predation risk during the neonatal period. I first identified resource selection strategies employed by lactating females to promote survival of neonates and then determined the primary factors affecting survival of neonates. I found lactating females selected for habitat that, despite decreased access to high quality forage, reduced the risk of predation by mountain lions. Understanding the availability of high quality neonate rearing habitat is an important consideration in restoring bighorn populations. My predictive resource selection function models will assist managers in identifying habitat that is most likely to meet the lambing needs of lactating bighorn females. I also found that despite the efforts of lactating female to protect neonates from risks of predation, predation was the strongest factor contributing to variable survival of neonates across subpopulations. I determined that neonates become less vulnerable as they age, were most vulnerable if they were born before the peak birth pulse (April) and if lactating females selected habitat farther from the safety of escape terrain. My work is the first to examine factors affecting selection of neonatal habitat by lactating females and survival of neonates within Sierra bighorn sheep populations. My results have elucidated potential management strategies that may inform recovery actions.

How plastic is migratory behavior? Quantifying elevational movement in a partially migratory alpine ungulate, the Sierra Nevada bighorn sheep (Ovis canadensis sierrae)

Tue, 14 May 2019 11:41:09 -0700

Elevational Migratory Behavior of Sierra Bighorn - Migratory species face well-documented global declines, but the causes of these declines remain unclear. One obstacle to better understanding these declines is uncertainty surrounding how migratory behavior is maintained. Most migratory populations are partially migratory, displaying both migrant and resident behaviors. Theory only provides two possible explanations for this coexistence of migration and residency: either these behaviors are fixed at the individual level or both behaviors are part of a single conditional strategy in which an individual’s migratory status (adoption of migrant or resident behavior) is plastic. Here we test for plasticity in migratory status and tactics (timing, distance, and duration of migration) in a federally endangered mountain caprid, the Sierra Nevada bighorn sheep (Ovis canadensis sierrae Grinnell, 1912). We used nonlinear modeling to quantitatively describe migratory behavior, analyzing 262 animal-years of GPS location data collected between 2005 and 2016 from 161 females across 14 subpopulations. Migratory tactics and prevalence varied by subpopulation. On average, individuals from partially migratory subpopulations switched migratory status every 4 years. Our results support the hypothesis that partial migration is maintained through a single conditional strategy. Understanding plasticity in migratory behavior will improve monitoring efforts and provide a rigorous basis for evaluating threats, particularly those associated with changing climate.

‘MigrateR’: extending model-driven methods for classifying and quantifying animal movement behavior

Tue, 14 May 2019 10:23:33 -0700

Modeling migration - To be useful, definitions of animal movement behavior (e.g. migration) should be quantitatively rigorous, flexible enough to accommodate variation in species biology (e.g. latitudinal vs elevational movement) and sufficiently general to allow comparison among different species. Recent studies have applied a model-driven approach to classifying and quantifying animal movement from global positioning system (GPS) location data. We improve upon these methods by 1) revising model structure to provide a simple biologically-defensible basis to reduce misclassification; 2) introducing a data-efficient tool that can be used to quantify and circumvent model sensitivity to starting location; and 3) illustrating how existing models can be adapted to describe short-distance migration, using elevational migration as an example. These improve-ments are included in ‘migrateR’, an open source R package that expands and automates model-driven classification and quantification of animal movement behavior. We demonstrate the software and these improved methods using GPS-collar location data from a long-distance migrant, elk Cervus elaphus, and a short-distance elevational migrant, Sierra Nevada bighorn sheep Ovis canadensis sierrae. We provide in-text example code and a supplementary script illustrating how default options can be revised to meet several common challenges in fitting movement models.

Integrating Nutrition, Resource Use, and Population Demographics to Inform Conservation of Endangered Species

Tue, 14 May 2019 09:34:07 -0700

Integrating Nutrition, Resource Use, and Population Demographics - Finding conservation actions and recovery goals for endangered species that are biologically sound requires thorough knowledge of ecology and habitat requirements and how changes in habitat affect population growth. One of the most profound ways by which habitat influences ungulates is through nutritional pathways (Monteith et al. 2014, Cook et al. 2016). Nutrition underpins growth, survival, and reproduction and because of its effects on demographic rates, nutrition is the fundamental building block of populations. Generally, implications of nutrition to conservation of wildlife have not been realized because data needed to establish cause-and-effect links between nutrition and population trajectory either are underappreciated or only exist conceptually. We aim to bridge the fields of nutrition and population ecology tools to quantify nutritional values of ‘foodscapes’, nutritional status of populations, and explicitly assess potential benefits of conservation actions that manipulate food supplies. ‘Foodscapes’ generated through our work will serve as innovative, yet tractable tools for conservation of endangered ungulates. Our work focuses on the federally endangered Sierra Nevada bighorn sheep (Ovis canadensis sierrae) in the Sierra Nevada of California.

2018 Status of Sierra Nevada Bighorn Sheep Herds in Yosemite National Park

Tue, 02 Apr 2019 13:20:13 -0700

Annual summary of Sierra Nevada bighorn sheep in Yosemite 2018 - This report summarizes the data developed in 2018 for the bighorn sheep herds that use habitat within Yosemite National Park. The geographic region in which these herds occur was labeled the northern recovery unit (NRU) in the recovery plan for Sierra Nevada bighorn sheep (U. S. Fish and Wildlife Service 2007) and includes two herd units defined in that plan (Mount Warren and Mount Gibbs herd units), as well as an additional one initiated in 2015 by translocation of Sierra bighorn to the Cathedral Range (Cathedral Range herd unit). Habitat for the Cathedral Range herd lies entirely within Yosemite National Park. The other two herd units straddle the Sierra crest and occupy a considerable amount of habitat on lands east of that crest managed by the U.S. Forest Service (Inyo and Toiyabe National Forests). Data reported here are part of a cooperative effort involving the California Department of Fish and Wildlife Recovery Program for Sierra Nevada Bighorn Sheep, the Sierra Nevada Bighorn Sheep Foundation, and Yosemite National Park.

Bighorn Sheep in California - Map

Thu, 08 Mar 2018 14:57:50 -0800

Bighorn Sheep in California - Map of distributions - Map showing historical distribution of bighorn sheep in California

Animal Movements Map - MountLangley_Male_S427 KML

Wed, 03 May 2017 09:34:58 -0700

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Wed, 03 May 2017 09:32:23 -0700

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Wed, 03 May 2017 09:25:31 -0700

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Wed, 03 May 2017 09:23:04 -0700

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Wed, 03 May 2017 09:20:35 -0700

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Wed, 03 May 2017 09:17:54 -0700

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Animal Movements Map - BigArroyo_Male_S202 pdf

Tue, 02 May 2017 16:17:31 -0700

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Tue, 02 May 2017 16:17:02 -0700

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Tue, 02 May 2017 16:15:48 -0700

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Tue, 02 May 2017 16:15:16 -0700

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Tue, 02 May 2017 16:14:31 -0700

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Tue, 02 May 2017 16:13:52 -0700

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Animal Movements Map - CathedralRange_Female_S367 pdf

Tue, 02 May 2017 16:13:05 -0700

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Tue, 02 May 2017 16:12:39 -0700

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Tue, 02 May 2017 16:12:01 -0700

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Tue, 02 May 2017 16:11:29 -0700

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Animal Movements Map - MountBaxter_Female_S263 pdf

Tue, 02 May 2017 16:10:58 -0700

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Tue, 02 May 2017 16:09:02 -0700

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Tue, 02 May 2017 14:56:43 -0700

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Tue, 02 May 2017 14:53:30 -0700

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Tue, 02 May 2017 14:30:37 -0700

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Tue, 02 May 2017 14:27:56 -0700

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Tue, 02 May 2017 13:47:43 -0700

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Animal Movements Map - SawmillCanyon_Female_S314 KML

Tue, 02 May 2017 13:44:26 -0700

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Animal Movements Map - CathedralRange_Male_S295 KML

Tue, 02 May 2017 13:29:32 -0700

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Animal Movements Map - CathedralRange_Female_S367 KML

Tue, 02 May 2017 13:26:49 -0700

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Tue, 02 May 2017 11:05:14 -0700

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Tue, 02 May 2017 11:02:18 -0700

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Animal Movements Map - WheelerRidge_Female_S417 KML

Mon, 01 May 2017 15:57:33 -0700

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Mon, 01 May 2017 15:56:57 -0700

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Mon, 01 May 2017 15:56:07 -0700

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Animal Movements Map - WheelerRidge_Male_S353 KML

Mon, 01 May 2017 15:55:42 -0700

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2014-2015 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program

Tue, 24 May 2016 09:00:58 -0700

2014-2015 Annual Report of the Sierra Nevada Bighorn Sheep Recovery Program - This report documents conservation and monitoring activities carried out between May 1, 2014 and April 30, 2015 by California Department of Fish and Wildlife’s (CDFW) Sierra Nevada Bighorn Sheep Recovery Program (the Recovery Program). The Recovery Program works to return the population of Sierra Nevada bighorn sheep (Ovis canadensis sierrae; hereafter Sierra bighorn) to a stable level through adaptive management based on an understanding of their distribution and demographics following the guidelines established by the Recovery Plan for Sierra Nevada Bighorn Sheep (the Recovery Plan, USFW 2007). Chief among the Recovery Program’s activities are regular population counts, cause specific mortality investigations, habitat and demographic modeling, captures to deploy radio collars, and translocations to increase the distribution of bighorn throughout the range.

Short-term vegetation response to wildfire in the eastern Sierra Nevada: Implications for recovering an endangered ungulate

Wed, 24 Feb 2016 09:30:05 -0800

Short-term vegetation response to wildfire in the eastern Sierra Nevada: Implications for recovering an endangered ungulate - We studied short-term changes in vegetation for two years following a summer wildfire on the winter ranges of Sierra Nevada bighorn sheep (Ovis canadensis sierrae). Forbs dominated burned areas and shrubs dominated unburned areas. Green forage (new-growth of all forage classes) biomass rebounded quickly; within two years green forage biomass was equal in burned and unburned areas, although total forage biomass remained greater in unburned areas. Plants in the burn had slightly higher crude protein but equivalent digestibility and phenology as plants in unburned areas. This, in combination with the shift toward more forb biomass, likely increased forage quality in burned areas. Forage models developed from ground-based measures of biomass performed better than the NDVI and were able to capture changes in forage composition, emphasizing the importance of field sampling to model vegetation. Based on microhistological analyses of fecal pellets, Sierra Nevada bighorn sheep whose winter ranges were extensively burned consumed more forbs than those with less burned habitat. Visibility was greater in burned areas compared with unburned areas, suggesting that burns may decrease predation risk from stalking predators. In conclusion, wildfire may have beneficial effects for Sierra bighorn by increasing forb availability, forage quality and visibility.

DOES MIGRATION MATTER? CAUSES AND CONSEQUENCES OF MIGRATORY BEHAVIOR IN SIERRA NEVADA BIGHORN SHEEP

Wed, 24 Feb 2016 09:25:05 -0800

Migration of bighorn sheep causes and consequences - Despite their potential conservation importance, the demographic implications of migratory behavior remain poorly understood. Sierra Nevada bighorn sheep (Ovis canadensis sierrae; hereafter “Sierra bighorn”) are federally-endangered and partially migratory. In summer, Sierra bighorn share high-elevation summer ranges, but in winter some individuals migrate to lower elevation for winter while others remain resident at high-elevation. Lower elevations have better forage in winter, but these areas also carry an increased risk of predation from Sierra bighorn's primary predator, the cougar (Puma concolor). We should therefore expect differences in winter conditions to result in demographic differences between migrants and residents. First, I developed new software tools in an open-source R package ‘migrateR’ for classifying migratory behavior, including novel techniques for identifying altitudinal migration. Applying these tools to Sierra bighorn showed that migratory behavior in this taxon is extremely flexible in both status (migrant v. resident) and tactics (e.g. timing, duration of movements), with individuals frequently switching migratory status between years. I tested for status-specific differences in winter resource use and selection by migrants and residents using resource selection functions across three scales. Migrants and residents showed scale-specific differences in resource selection offering contrasting solutions to a forage-predation tradeoff. Residents avoided predation risk at the coarsest scale, but focused on forage in fine-scale selection, whereas migrants selected for forage at the coarsest spatial scale and focused on avoided predation risk at finer scales. This pattern of selection resulted in migrants gaining better access to forage. The amount of migrant habitat predicted differences in the prevalence of migration across eight populations. Lastly, I tested causes and consequences of migratory behavior in Sierra bighorn. Migratory propensity increased with winter severity. Individuals that were still lactating in fall were highly likely to migrate, but the strength of this effect declined with body mass. I failed to find an effect of winter elevation on adult female survival. Finally, Sierra bighorn were more likely to be observed with a lamb following residency than following migration. These results suggest that where residency is viable, residents make greater per-capita contributions to population growth than do migrants.

2015 Translocation Plan for Sierra Nevada Bighorn Sheep: A Focus on Strategic Planning

Tue, 23 Feb 2016 14:11:18 -0800

Strategic Planning for Translocating Sierra Nevada Bighorn Sheep - Sierra Nevada bighorn sheep have increased from 100 to 600 animals between 1995 and present, yet numbers and distribution remain below recovery goals. Translocations are required to reoccupy historic habitat and ensure the persistence of Sierra Nevada bighorn, a federally endangered subspecies (USFWS 2007). Here we present 2 phases of translocations planned for the next 10-20 years. The first phase of translocations will ensure the long-term viability of herds (populations) and recovery units (metapopulations) with small population sizes and also ensure that recovery criteria are met. The second phase of translocations increases connectivity within and between recovery units. Many of phase 2 translocations are not necessary to meet recovery criteria; however, these translocations will build metapopulation dynamics to improve population viability and genetic diversity in the absence of future management intervention. We anticipate completing phase 1 translocations in 5-10 years and phase 2 translocations within 10-20 years.

Evaluating Potential Overlap Between Pack Stock and Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) in Sequoia and Kings Canyon National Parks, California

Mon, 22 Jun 2015 16:25:15 -0700

Evaluating Potential Overlap Between Pack Stock and Sierra Nevada Bighorn Sheep (Ovis canadensis sierrae) in Sequoia and Kings Canyon National Parks, California - Pack stock (horses, mules, burros, llamas, and goats) are frequently assumed to have negative effects on public lands, but there is a general lack of data to be able to quantify the degree to which this is actually the case. Sequoia and Kings Canyon National Parks have received complaints that pack stock may affect Sierra Nevada bighorn sheep, that occurs in largely disjunct herds in the Sierra Nevada Range of California. The potential effects are thought to be displacement of SNBS from meadows on their summer range (altered habitat use) or, more indirectly, through changes in SNBS habitat or forage quality. Our goals were to conduct an association analysis to quantify the degree of potential spatial overlap in meadow use between SNBS and pack stock and to compare differences in vegetation community composition, structure, and diversity among meadows with different levels of use by bighorn sheep and pack stock. For the association analysis, we used two approaches: (1) we quantified the proportion of meadows that were within the herd home ranges of bighorn sheep and were potentially open to pack stock, and, (2) we used Monte Carlo simulations and use-availability analyses to compare the proportion of meadows used by bighorn sheep relative to the proportional occurrence or area of meadows available to bighorn sheep that were used by pack stock. To evaluate potential effects of pack stock on meadow plant communities and SNBS forage, we sampled vegetation in 2011 and 2012 at 100 plots to generate data that allowed us to compare: 1. Herbaceous plant species composition, structure, and diversity in plots with different combinations of use by pack stock and SNBS; 2. Cover of bare ground in plots with different combinations of use by pack stock and SNBS; and, 3. Total cover, diversity, and species composition of SNBS forage species in plots with different combinations of use by pack stock and SNBS. The association analyses indicated the potential for overlap between pack stock and SNBS was minimal; only 1 percent of the potential meadow area in the SNBS herd home ranges overlapped that of pack stock meadows. There were no systematic differences in overall vegetation structure or composition, or in diversity, cover, or composition of forage species, that indicated pack stock were altering SNBS habitat or affecting their nutrition. Variation in plant species composition was influenced primarily by random differences among meadows and environmental gradients, and there was little evidence that pack stock use contributed in meaningful ways to this variation. The few differences among meadows with different levels of use by bighorn sheep and pack stock either were minor or were not in a direction consistent with negative effects of pack stock on SNBS. We conclude that the current plan for managing pack stock grazing has been successful in minimizing significant negative effects on Sierra Nevada bighorn sheep at Sequoia and Kings Canyon National Parks.

LocationMapS237

Wed, 22 Apr 2015 14:57:20 -0700

GPS Locations Map for S237 (SNBS Ewe - Mt. Warren) -

LocationMapS239

Wed, 20 Feb 2013 08:50:29 -0800

GPS Locations Map for S239 (SNBS Ram - Mt. Warren) -

LocationMapS79

Wed, 20 Feb 2013 08:47:46 -0800

GPS Locations Map for S79 (SNBS Ram - Mt. Gibbs) -

LocationMapS160

Wed, 03 Oct 2012 14:08:37 -0700

GPS Locations Map for S160 (SNBS Ewe - Mt. Gibbs) -

LocationMapS216

Wed, 03 Oct 2012 14:08:13 -0700

GPS Locations Map for S216 (SNBS Ram - Mt. Warren) -

LocationMapS215

Wed, 03 Oct 2012 14:07:50 -0700

GPS Locations Map for S215 (SNBS Ram - Mt. Gibbs) -

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

Mon, 13 Aug 2012 15:29:55 -0700

Designation of critical habitat for Sierra Nevada bighorn sheep - 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.

LocationMapS78

Mon, 13 Aug 2012 15:28:56 -0700

GPS Locations Map for S78 (SNBS Ram - Mt. Gibbs) -

LocationMapS187

Mon, 13 Aug 2012 15:28:08 -0700

GPS Locations Map for S187 (SNBS Ewe - Mt. Warren) -

A process for identifying and managing risk of contact between Sierra Nevada bighorn sheep and domestic sheep

Tue, 07 Aug 2012 11:22:50 -0700

Managing disease risk for Sierrra Nevada bighorn sheep - Managing disease risk for Sierra Nevada bighorn sheep

2010-2011 Annual report of the Sierra Nevada bighorn sheep recovery program: A decade in review

Wed, 21 Mar 2012 16:48:49 -0700

Ten year report on the Sierra Nevada bighorn sheep program and annual report for 2010-2011 - This report presents a review of the Sierra Nevada Bighorn Sheep Recovery Program from 1999, when Sierra Nevada bighorn sheep were placed on the federal endangered species list, to June 30, 2011. Detailed data from 2010-2011 are listed in the Appendices. Since 1999, Sierra bighorn numbers have increased from just over 100 animals to about 400. The current reproductive base of almost 200 females over 1 year old is about two-thirds of the numerical recovery goal of 305 females . Of the 12 herd units required for recovery, only 4 remain vacant as of the 2010-2011 reporting year. Herds that grew substantially since listing (Wheeler Ridge, Mount Langley, Sawmill Canyon, and Mount Baxter) tended to have the highest growth rates early in the decade. During periods of high growth, survival rates of adult females generally exceeded 90%. Periods of slowed population growth were accompanied by more variable and poorer adult female survival and declining recruitment of yearling females. Mountain lion predation was the highest known cause of mortality and was concentrated in herds in proximity to dense mule deer winter ranges. The Recovery Program is directed by the Recovery Plan for Sierra Nevada bighorn sheep drafted in 2001 which presents the conservation strategies that California’s Department of Fish and Game (DFG) has employed over the last decade. The Recovery Plan has a 20-year implementation schedule beginning when the plan was released in 2007. The stated goal for downlisting is 2017. Considerable progress has been made in implementing the Recovery Plan conservation strategies. These strategies focus on 1) increasing the number and distribution of bighorn sheep through augmentations and habitat enhancement projects and 2) reducing threats that limit their survival by managing predators and reducing the proximity of domestic sheep grazing allotments. Based on the first strategy, we implemented three translocations to augment small herds. Additionally, we planned prescribed burns and initiated two to enhance the quality of habitat for bighorn sheep. Following the second strategy, we removed mountain lions when they posed an imminent threat to bighorn sheep, and land management agencies worked to shift grazing away from areas near bighorn recovery units. After reviewing 11 years of progress, we are optimistic that we could meet the goals for downlisting to threatened status within the next decade, barring any catastrophes. If we are to meet this ambitious timeline, key recovery strategies need to continue. Implementing translocations for reintroductions to vacant herd units is essential to achieve the distribution required to meet recovery goals. This necessitates adaptive management and a predator management program to protect herds used as a source of translocation stock so that reintroductions and augmentations can occur.

Annual report 2009-2010 Sierra Nevada bighorn sheep recovery program July 2009 - June 2010

Mon, 13 Feb 2012 16:47:21 -0800

Annual summary of Sierra Nevada bighorn sheep program 2009-2010 - The goal of the Sierra Nevada Bighorn Sheep Recovery Program is to achieve a population size and geographic distribution of bighorn sheep in the Sierra Nevada that ensures long-term viability of the entire population and warrants its delisting as an endangered species. The Recovery Plan for Sierra Nevada bighorn sheep calls for an adaptive management approach in which timely decisions are made based on collected data. To make informed decisions to conserve bighorn, the Recovery Program monitors population estimates, demographic rates, and distribution. The Recovery Program focuses on four major conservation activities: 1) translocating bighorn to augment existing herds or to reintroduce bighorn to areas within their historic range, 2) enhancing habitat through small prescribed burns, 3) reducing the risk of disease in bighorn by limiting exposure to domestic sheep and goats, and 4) managing predation on bighorn by mountain lions. This report summarizes conservation activities conducted and demographic data collected during July 1, 2009-June 30, 2010.

Translating Effects of Inbreeding Depression on Component Vital Rates to Overall Population Growth in Endangered Bighorn Sheep

Mon, 14 Nov 2011 09:57:07 -0800

Effects of Inbreeding Depression on Vital Rates and Population Growth for Bighorn Sheep - Evidence of inbreeding depression is commonly detected from the fitness traits of animals, yet its effects on population growth rates of endangered species are rarely assessed. We examined whether inbreeding depression was affecting Sierra Nevada bighorn sheep ( Ovis canadensis sierrae), a subspecies listed as endangered under the U.S. Endangered Species Act. Our objectives were to characterize genetic variation in this subspecies; test whether inbreeding depression affects bighorn sheep vital rates (adult survival and female fecundity); evaluate whether inbreeding depression may limit subspecies recovery; and examine the potential for genetic management to increase population growth rates. Genetic variation in 4 populations of Sierra Nevada bighorn sheep was among the lowest reported for any wild bighorn sheep population, and our results suggest that inbreeding depression has reduced adult female fecundity. Despite this population sizes and growth rates predicted from matrix-based projection models demonstrated that inbreeding depression would not substantially inhibit the recovery of Sierra Nevada bighorn sheep populations in the next approximately 8 bighorn sheep generations (48 years). Furthermore, simulations of genetic rescue within the subspecies did not suggest that such activities would appreciably increase population sizes or growth rates during the period we modeled (10 bighorn sheep generations, 60 years). Only simulations that augmented the Mono Basin population with genetic variation from other subspecies, which is not currently a management option, predicted significant increases in population size. Although we recommend that recovery activities should minimize future losses of genetic variation, genetic effects within these endangered populations—either negative (inbreeding depression) or positive (within subspecies genetic rescue)—appear unlikely to dramatically compromise or stimulate short-term conservation efforts. The distinction between detecting the effects of inbreeding depression on a component vital rate (e.g., fecundity) and the effects of inbreeding depression on population growth underscores the importance of quantifying inbreeding costs relative to population dynamics to effectively manage endangered populations.

Notice of Intent: Sequoia and Kings Canyon National Park EA

Thu, 20 Oct 2011 12:25:54 -0700

CEQA -

Errata to Sequoia and Kings Canyon National Parks Environmental Assessment

Wed, 19 Oct 2011 14:29:45 -0700

NEPA and CEQA -

Sequoia and Kings Canyon National Parks Finding of No Significant Impact

Wed, 19 Oct 2011 14:27:31 -0700

NEPA and CEQA -

Sequoia and Kings Canyon National Parks Wilderness Minimum Tool Analysis

Wed, 19 Oct 2011 14:25:38 -0700

NEPA and CEQA -

Sierra Nevada Bighorn Sheep Environmental Assessment

Wed, 19 Oct 2011 14:21:25 -0700

NEPA and CEQA -

Notice of Determination: Sequoia Kings Canyon National Parks EA

Wed, 19 Oct 2011 14:12:50 -0700

CEQA -

Google Earth Map Locations S105 Mt Warren 2011

Thu, 15 Sep 2011 11:12:27 -0700

Google Earth Map Locations S105 Mt Warren 2011 -

The Relocation of Bighorn Sheep in the Sierra Nevada of California

Mon, 08 Aug 2011 13:39:57 -0700

1981 Status of translocated populations of Sierra Nevada bighorn sheep - 1981 Status of translocated populations of Sierra Nevada bighorn sheep

1994 Mount Baxter Bighorn Herd Status

Wed, 03 Aug 2011 16:41:09 -0700

1994 Mount Baxter herd census - Summary of Mt. Baxter population survey 1994 and prior years

Diet of Cougars (Puma concolor) Following a Decline in a Population of Mule Deer (Odocoileus hemionus): Lack of Evidence for Switching Prey

Mon, 01 Aug 2011 16:42:31 -0700

Diet of Cougars Following a Decline in a Population of Mule Deer : Lack of Evidence for Switching Prey - We investigated diet of cougars (Puma concolor) in the eastern Sierra Nevada, California, following a decline in the population of mule deer (Odocoileus hemionus). Mule deer declined 84% from 1985 to 1991, a period concurrent with declines in bighorn sheep (Ovis canadensis sierrae; an endangered taxon). An index to numbers of cougars lagged behind those declines, with a reduction of ca. 50% during 1992–1996. We determined diet of cougars by analysis of fecal samples collected during 1991–1995, when the population of mule deer was ,25% of its former size. Mule deer was in 79% of 178 feces in winter and 58% of 74 feces in summer. Although most (69%) fecal samples in winter were ,5 km from, or within (25%) winter range of bighorn sheep, none contained evidence of bighorn sheep. One fecal sample in summer contained remains of bighorn sheep, indicating that those ungulates were not an important component of the diet during our investigation.

Recovery plan for the Sierra Nevada bighorn sheep

Tue, 21 Jun 2011 09:48:12 -0700

Recovery plan for the Sierra Nevada bighorn sheep - Recovery plan for the Sierra Nevada bighorn sheep

An Analysis of Translocation Options for the Recovery of Sierra Nevada Bighorn Sheep

Tue, 21 Jun 2011 09:45:13 -0700

Translocation of Sierra Nevada Bighorn Sheep - A draft of translocation efforts needed to support recovery of Sierra Nevada Bighorn Sheep

A Conservation Strategy of Sierra Nevada Bighorn Sheep

Tue, 21 Jun 2011 09:42:40 -0700

Sierra Nevada Bighorn Sheep Recovery Plan - A published early draft of a recovery plan for Sierra Nevada Bighorn Sheep.

Sierra Nevada Bighorn Sheep Recovery and Conservation Plan

Tue, 21 Jun 2011 09:39:38 -0700

Sierra Nevada Bighorn Sheep Recovery Plan - Early documentation of recovery efforts needed for Sierra Nevada Bighorn Sheep.

Microsatellite diversity in Sierra Nevada mountain sheep herds

Tue, 22 Mar 2011 11:10:48 -0700

DNA extraction using microsatellites in Sierra Nevada bighorn sheep - DNA extraction using microsatellites in Sierra Nevada bighorn sheep

The role of precipitation and temperature in the winter range diet quality of mountain sheep of the Mount Baxter herd, Sierra Nevada

Tue, 22 Mar 2011 11:10:48 -0700

Precipitation and Temperature vs. diet quality of bighorn sheep - How temperature and precipiation affect diet quality of bighorn sheep in the Mount Baxter herd in the Sierra Nevada

Habitat selection by mountain sheep and mule deer: A step toward understanding ecosystem health from the desert to the alpine

Tue, 22 Mar 2011 11:10:48 -0700

Using a resource selection function to define habitat for bighorn sheep and mule deer - Using a resource selection function to define habitat for bighorn sheep and mule deer

Sierra Nevada Bighorn Sheep: 2004-05 Status

Tue, 22 Mar 2011 11:10:47 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Life-history consequences of maternal condition in Alaskan moose

Tue, 22 Mar 2011 11:10:47 -0700

Life-history consequences of maternal condition in Alaskan moose - Life-history consequences of maternal condition in Alaskan moose

Tooth Extraction from Live-Captured Mule Deer in the Absence of Chemical Immobilization

Tue, 22 Mar 2011 11:10:47 -0700

Tooth Extraction from Live-Captured Mule Deer in the Absence of Chemical Immobilization - Tooth Extraction from Live-Captured Mule Deer in the Absence of Chemical Immobilization

Efficacy of aerial telemetry as an aid to capture specific individuals: a comparison of two techniques.

Tue, 22 Mar 2011 11:10:47 -0700

Efficacy of aerial telemetry as an aid to capture specific individuals: a comparison of two techniques. - Efficacy of aerial telemetry as an aid to capture specific individuals: a comparison of two techniques.

Peculiar antler cast by moose on the Copper River Delta, Alaska.

Tue, 22 Mar 2011 11:10:47 -0700

Moose antlers, unusual - Moose antlers, unusual

Sierra Nevada Bighorn Sheep Program Report 3rd Quarter 2008

Tue, 22 Mar 2011 11:10:47 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Ecology of mountain sheep reintroduced in the Sierra Nevada of California

Tue, 22 Mar 2011 11:10:47 -0700

Ecology of mountain sheep reintroduced in Lee Vining, California - Ecology of mountain sheep reintroduced in Lee Vining, California

Cougar management guidelines

Tue, 22 Mar 2011 11:10:47 -0700

Cougar management guidelines - Cougar management guidelines

Changes in bighorn sheep habitat of the Sierra Nevada

Tue, 22 Mar 2011 11:10:47 -0700

Analysis of changes in the habitat of bighorn sheep based on comparing geo-referenced photos from the past to current photos. - Analysis of changes in the habitat of bighorn sheep based on comparing geo-referenced photos from the past to current photos.

Habitat selection by mule deer: forage benefits or risk of predation?

Tue, 22 Mar 2011 11:10:47 -0700

Habitat selection by mule deer: forage benefits or risk of predation? - Habitat selection by mule deer: forage benefits or risk of predation?

Interagency domestic sheep management strategy

Tue, 22 Mar 2011 11:10:47 -0700

Managing disease risk in bighorn sheep when exposure to domestic sheep is possible - Managing disease risk in bighorn sheep when exposure to domestic sheep is possible

Sierra Nevada Bighorn Sheep Herds: 2003 Status

Tue, 22 Mar 2011 11:10:46 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep: 2004-05 Status

Tue, 22 Mar 2011 11:10:46 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep: 2007-08 Status

Tue, 22 Mar 2011 11:10:46 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep Program Report 1st Quarter 2009

Tue, 22 Mar 2011 11:10:46 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Vitamin E, selenium, and reproductive losses in Alaskan moose.

Tue, 22 Mar 2011 11:10:46 -0700

Vitamin E, selenium, and reproductive losses in Alaskan moose. - Vitamin E, selenium, and reproductive losses in Alaskan moose.

Protein conservation in female caribou (rangifer tarandus): effects of decreasing diet quality during winter

Tue, 22 Mar 2011 11:10:46 -0700

Protein conservation in female caribou (rangifer tarandus): effects of decreasing diet quality during winter - Protein conservation in female caribou (rangifer tarandus): effects of decreasing diet quality during winter

Sierra Nevada Bighorn Sheep Herds: 2001 Status

Tue, 22 Mar 2011 11:10:46 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep Program Report 2nd Quarter 2009

Tue, 22 Mar 2011 11:10:46 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Mountain lion

Tue, 22 Mar 2011 11:10:45 -0700

Mountain Lions - General overview of mountain lions

Mountain sheep in California: A historical perspective

Tue, 22 Mar 2011 11:10:45 -0700

History of bighorn sheep in California - History of the management of bighorn sheep in California

Modeling risks of disease transmission from domestic sheep to bighorn sheep: Implications for the persistence and restoration of an endangered endemic ungulate

Tue, 22 Mar 2011 11:10:45 -0700

Assessing risk of disease transmission at the wildlife-livestock interface: the case of the sierra nevada bighorn sheep - Assessing risk of disease transmission at the wildlife-livestock interface: the case of the sierra nevada bighorn sheep

Mammalian Prey Selection by a Captive Bobcat

Tue, 22 Mar 2011 11:10:45 -0700

Bobcat prey - Bobcat prey

Using vaginal implant transmitters to aid in capture of mule deer neonates

Tue, 22 Mar 2011 11:10:45 -0700

Using vaginal implant transmitters to aid in capture of mule deer neonates - Using vaginal implant transmitters to aid in capture of mule deer neonates

Validating predictive models of nutritional condition for mule deer.

Tue, 22 Mar 2011 11:10:45 -0700

Validating predictive models of nutritional condition for mule deer. - Validating predictive models of nutritional condition for mule deer.

Combining ground count, telemetry, and markresight data to infer population dynamics in an endangered species

Tue, 22 Mar 2011 11:10:45 -0700

Combining ground count, telemetry, and mark-resight data to infer population dynamics in an endangered species - Combining ground count, telemetry, and mark-resight data to infer population dynamics in an endangered species

A history of bighorn sheep management in the Sierra Nevada

Tue, 22 Mar 2011 11:10:44 -0700

History of bighorn sheep in the Sierra Nevada - A brief history of bighorn sheep management in the Sierra Nevada, California

Body condition of radio-collared mule deer while injured and following recovery

Tue, 22 Mar 2011 11:10:44 -0700

Body condition of radio-collared mule deer while injured and following recovery - Body condition of radio-collared mule deer while injured and following recovery

Predator damage management to protect the federally endangered bighorn sheep, California

Tue, 22 Mar 2011 11:10:44 -0700

Decision and findings of no significant impact for predator management from EA for implementation of SNBS recovery plan - Decision and findings of no significant impact for predator management from EA for implementation of SNBS recovery plan

Population-specific vital rate contributions influence management of an endangered ungulate

Tue, 22 Mar 2011 11:10:44 -0700

Adaptive management of Sierra Nevada bighorn sheep based on popluation specific vital rates - Adaptive management of Sierra Nevada bighorn sheep based on population specific vital rates

Nutritional investigations and management of captive moose

Tue, 22 Mar 2011 11:10:44 -0700

Moose nutrition, captive - Moose nutrition, captive

Nitrogen and carbon isotope fractionation between mothers, neonates, and nursing offspring.

Tue, 22 Mar 2011 11:10:44 -0700

Nitrogen and Carbon Isotope Fractionation between Mothers, Neonates, and Nursing Offspring - Nitrogen and Carbon Isotope Fractionation between Mothers, Neonates, and Nursing Offspring

New technology for moose management: a workshop

Tue, 22 Mar 2011 11:10:44 -0700

Moose management - Moose management

Mule Deer Movements in Response to Military Activity in Southeast Colorado

Tue, 22 Mar 2011 11:10:44 -0700

Mule deer movements in response to military activity in southeastern Colorado - Mule deer movements in response to military activity in southeastern Colorado

Mountain sheep and coyotes: Patterns of predator evasion in a mountain ungulate

Tue, 22 Mar 2011 11:10:44 -0700

Investigates the relationship among terrain type, reactions of prey, and age and sex of prey and outcomes of encounters between mountain sheep and coyotes - Investigates the relationship among terrain type, reactions of prey, and age and sex of prey and outcomes of encounters between mountain sheep and coyotes

Ultrasonic fat measurement of captive yearling bull moose

Tue, 22 Mar 2011 11:10:43 -0700

Using ultrasound for determinancy of body fat in yearling moose - Using ultrasound for determinancy of body fat in yearling moose

Sierra Nevada bighorn sheep: 1999 Population Status

Tue, 22 Mar 2011 11:10:43 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Response of moose forages to mechanical cutting on the Copper River Delta, Alaska

Tue, 22 Mar 2011 11:10:43 -0700

Response of moose forages - Response of moose forages to mechanical cutting on the Copper River Delta, Alaska

Sexual segregation in Moose Alces alces: an experimental test of foraging behaviour

Tue, 22 Mar 2011 11:10:43 -0700

Sexual segregation in Moose Alces alces: an experimental test of foraging behaviour - Sexual segregation in Moose Alces alces: an experimental test of foraging behavior

Relationships between blood-serum and depth of rump fat in Alaskan moose

Tue, 22 Mar 2011 11:10:43 -0700

Moose body fat and blood serum relationships - Moose body fat and blood serum relationships

Isolation, purification, and characterization of pregnancy-specific protein B from elk and moose placenta.

Tue, 22 Mar 2011 11:10:43 -0700

Isolation, purification, and characterization of pregnancy-specific protein B from elk and moose placenta. - Isolation, purification, and characterization of pregnancy-specific protein B from elk and moose placenta.

Effects of mountain lion predation on bighorn sheep in the Sierra Nevada and Granite Mountains of California

Tue, 22 Mar 2011 11:10:43 -0700

Lion Predation on Bighorn Sheep - Lion Predation on Bighorn Sheep

Consequences of a mammalian predator-prey disequilibrium in the Great Basin Desert

Tue, 22 Mar 2011 11:10:43 -0700

Ecological interactions in the Great Basin Desert of deer, mountain lions and bighorn sheep - Ecological interactions in the Great Basin Desert of deer, mountain lions and bighorn sheep

Sierra Nevada Bighorn Sheep Program Report 4th Quarter 2008

Tue, 22 Mar 2011 11:10:43 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Sierra Nevada Bighorn Sheep Program Report 2nd quarter 2007

Tue, 22 Mar 2011 11:10:43 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Application of the document entitled a process for identifying and managing risk of contact between Sierra Nevada bighorn sheep and domestic sheep

Tue, 22 Mar 2011 11:10:43 -0700

Managing disease risk for Sierrra Nevada bighorn sheep - Managing disease risk for Sierrra Nevada bighorn sheep

Xylazine immobilization of moose with yohimbine or tolazoline as an antagonist: a comparison to carfentanil and Naltrexone

Tue, 22 Mar 2011 11:10:42 -0700

Immobilization drugs in moose, xylazine, yohimbine and tolazoline - Immobilization drugs in moose, xylazine, yohimbine and tolazoline

Neck lesions in ungulates from collars incorporating satellite technology

Tue, 22 Mar 2011 11:10:42 -0700

Neck lesions in ungulates from collars incorporating satellite technology - Neck lesions in ungulates from collars incorporating satellite technology

Incisor arcades of Alaskan moose: is dimorphism related to sexual segregation?

Tue, 22 Mar 2011 11:10:42 -0700

Incisor arcades of Alaskan moose: is dimorphism related to sexual segregation? - Incisor arcades of Alaskan moose: is dimorphism related to sexual segregation?

Spatio-temporal constraints on moose habitat in coastal Alaska: vegetation succession and climate.

Tue, 22 Mar 2011 11:10:42 -0700

Spatio-temporal constraints on moose habitat in coastal Alaska: vegetation succession and climate. - Spatio-temporal constraints on moose habitat in coastal Alaska: vegetation succession and climate.

Diagnosis of pregnancy and twinning in moose by ultrasonography and serum assay.

Tue, 22 Mar 2011 11:10:42 -0700

Using ultrasound for determinancy of pregnancy in moose - Using ultrasound for determinacy of pregnancy in moose

Validation of mule deer body composition using in vivo and post-mortem indices of nutritional condition

Tue, 22 Mar 2011 11:10:42 -0700

Validation of mule deer body composition using in vivo and post-mortem indices of nutritional condition - Validation of mule deer body composition using in vivo and post-mortem indices of nutritional condition

Spatio-temporal constraints on moose habitat and carrying capacity in coastal Alaska: vegetation succession and climate

Tue, 22 Mar 2011 11:10:42 -0700

Spatio-temporal constraints on moose habitat and carrying capacity in coastal Alaska: vegetation succession and climate - Spatio-temporal constraints on moose habitat and carrying capacity in coastal Alaska: vegetation succession and climate

Predicting body fat and body mass in moose with ultrasonography

Tue, 22 Mar 2011 11:10:42 -0700

Predicting body fat and body mass in moose with ultrasonography - Predicting body fat and body mass in moose with ultrasonography

Sierra Nevada Bighorn Sheep: 2006-07 Status

Tue, 22 Mar 2011 11:10:41 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada bighorn sheep: 2008-09 status

Tue, 22 Mar 2011 11:10:41 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep Program Report 1st Quarter 2008

Tue, 22 Mar 2011 11:10:41 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Sierra Nevada Bighorn Sheep Program Report 2nd Quarter 2008

Tue, 22 Mar 2011 11:10:41 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Sierra Nevada Bighorn Sheep Program Report 3rd Quarter 2007

Tue, 22 Mar 2011 11:10:41 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Sierra Nevada Bighorn Sheep Program Report 4th Quarter 2007

Tue, 22 Mar 2011 11:10:41 -0700

Quarterly Report of SNBS Program Acitivities - Quarterly Report of SNBS Program Activities

Sierra Nevada Bighorn Sheep Program Semiannual Report July_December 2009

Tue, 22 Mar 2011 11:10:41 -0700

Semiannul Report of SNBS Program Acitivities - Semiannual Report of SNBS Program Activities

Factors affecting birth dates of sympatric deer in west-central Texas

Tue, 22 Mar 2011 11:10:41 -0700

Factors affecting birth dates of sympatric deer in west-central Texas - Factors affecting birth dates of sympatric deer in west-central Texas

Revisions of rump fat and body scoring indices for deer, elk, and moose

Tue, 22 Mar 2011 11:10:40 -0700

Revisions of rump fat and body scoring indices for deer, elk, and moose - Revisions of rump fat and body scoring indices for deer, elk, and moose

Effects of Tooth Extraction on Body Condition and Reproduction of Mule Deer

Tue, 22 Mar 2011 11:10:40 -0700

Effects of Tooth Extraction on Body Condition and Reproduction of Mule Deer - Effects of Tooth Extraction on Body Condition and Reproduction of Mule Deer

Effect of enhanced nutrition on mule deer population rate of change

Tue, 22 Mar 2011 11:10:40 -0700

Effect of enhanced nutrition on mule deer population rate of change - Effect of enhanced nutrition on mule deer population rate of change

Evaluating GPS collar error: a critical evaluation of Televilt Posrec-Science collars and a method for screenign location data

Tue, 22 Mar 2011 11:10:40 -0700

GPS collar data screening methods - GPS collar data screening methods

Sexual segregation in Sierra Nevada bighorn sheep, Ovis canadensis sierrae: Ramifications for conservation

Tue, 22 Mar 2011 11:10:40 -0700

Sexual segregation in Sierra Nevada bighorn sheep - Sexual segregation in Sierra Nevada bighorn sheep

The efficacy of measures to minimize contact between domestic sheep and Sierra Nevada bighorn sheep on the Humboldt-Toiyabe National Forest, Mono County, California

Tue, 22 Mar 2011 11:10:40 -0700

Minimizing Contact between domestic sheep and bighorn sheep in the Sierra Nevada - Minimizing Contact between domestic sheep and bighorn sheep in the Sierra Nevada

Nutritional quality of willows for moose: effects of twig age and diameter.

Tue, 22 Mar 2011 11:10:40 -0700

Nutritional quality of willows for moose: effects of twig age and diameter. - Nutritional quality of willows for moose: effects of twig age and diameter.

Sierra Nevada Bighorn Sheep Herds: 2000 Status

Tue, 22 Mar 2011 11:10:40 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Sierra Nevada Bighorn Sheep Herds: 2002 Status

Tue, 22 Mar 2011 11:10:40 -0700

Annual summary of demographics of Sierra Nevada bighorn sheep - Annual summary of demographics of Sierra Nevada bighorn sheep

Selection of mule deer by mountain lions and coyotes: effects of hunting style, body size, and reproductive status

Tue, 22 Mar 2011 11:10:39 -0700

Selection of mule deer by mountain lions and coyotes: effects of hunting style, body size, and reproductive status - Selection of mule deer by mountain lions and coyotes: effects of hunting style, body size, and reproductive status

Diagnosing pregnancy, in utero litter size, and fetal growth with ultrasound in wild, free-ranging wolves.

Tue, 22 Mar 2011 11:10:39 -0700

Diagnosing pregnancy, in utero litter size, and fetal growth with ultrasound in wild, free-ranging wolves. - Diagnosing pregnancy, in utero litter size, and fetal growth with ultrasound in wild, free-ranging wolves.

A specific radioimmunoassay for moose and elk pregnancy-specific protein B in serum

Tue, 22 Mar 2011 11:10:39 -0700

A Serum Pregnancy Test with a Specific Radioimmunoassay for Moose and Elk Pregnancy-Specific Protein B - A Serum Pregnancy Test with a Specific Radioimmunoassay for Moose and Elk Pregnancy-Specific Protein B

Sexual segregation and foraging ecology of sierra nevada bighorn sheep during winter

Tue, 22 Mar 2011 11:10:39 -0700

Forage use by Sierra Nevada bighorn sheep - Forage use by Sierra Nevada bighorn sheep

Cranial morphometric and evolutionary relationships in the northern range of OVis canadensis

Tue, 22 Mar 2011 11:10:39 -0700

Taxonomy of bighorn sheep - Taxonomy of bighorn sheep

Short-term effects of wildfire on Sierra Nevada bighorn sheep habitat ecology

Tue, 22 Mar 2011 11:10:39 -0700

Wildfire effect on Sierra Nevada bighorn sheep ecology - various

Forage site characteristics of reintroduced mountain sheep in the Sierra Nevada, California

Tue, 22 Mar 2011 11:10:39 -0700

Analysis of forage for bighorn sheep in Lee Vining Canyon area, Sierra Nevada - Analysis of forage for bighorn sheep in Lee Vining Canyon area, Sierra Nevada

Selection of mule deer by mountain lions and coyotes: effects of hunting style, body size, and reproductive status

Tue, 22 Mar 2011 11:10:39 -0700

Genetic bottlenecks resulting from restoration efforts: The case of bighorn sheep in Badlands National Park

Tue, 22 Mar 2011 11:10:39 -0700

Genetic bottlenecks bighorn sheep - various

Experiments in DNA extraction and PCR amplification from bighorn sheep feces: The importance of DNA extraction method

Tue, 22 Mar 2011 11:10:39 -0700

DNA extraction from bighorn feces - DNA extraction from bighorn feces

Sierra Nevada bighorn sheep: An analaysis of management alternatives

Tue, 22 Mar 2011 11:10:39 -0700

Discussion of how to manage bighorn sheep in the Sierra Nevada - Discussion of how to manage bighorn sheep in the Sierra Nevada

Correct nomenclature for Sierra Nevada bighorn sheep

Tue, 22 Mar 2011 11:10:39 -0700

Taxonomy of bighorn sheep - Discusses the correct taxonomy of bighorn sheep in North America

1995 Status of three bighorn sheep populations in the Sierra Nevada