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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Microhabitat Selection by Greater Sage-Grouse Hens in Southern Wyoming

Mabray, Scott T. 01 May 2015 (has links)
Greater sage-grouse (Centrocercus urophasianus) populations have declined throughout the western United States over the past 3 decades. Habitat loss within the sagebrush steppe ecosystem is a major factor leading to sage-grouse population decline. Hen sage-grouse were captured, marked, and tracked during the summer of 2012 in southwestern and south-central Wyoming. I performed vegetation surveys, and avian point counts were performed at 1 early-season brood location, 1 late-season brood location, and an accompanying random location for each marked hen regardless of reproductive status. Multinomial models were run to determine what habitat variables were most informative in predicting site selection by hen sage-grouse. During early-brood season, hen sage-grouse with chicks selected sites that had high total shrub cover density; these areas also exhibited high densities of American kestrels (Falco sparverius). They did not avoid areas with common ravens (Corvus corax). Hen sage-grouse not accompanied by a brood selected sites with high total shrub cover and low densities of common ravens and American kestrels. During late-brood season, hen sage-grouse that were accompanied by a brood selected sites with high shrub cover and low densities of small avian predators, such as black-billed magpies (Pica hudsonia) and American kestrels as well as medium-sized predators, such as common ravens, buteo hawks (Buteo spp.), and northern harriers (Circus cyaneus). Hens that were not accompanied by broods were more often found in sites with high total shrub cover and low densities of small avian predators, but selected sites with higher densities of medium-sized predators. Hen sage-grouse select areas with high total shrub cover during early and late-brood season regardless of their reproductive status. By avoiding predators and selecting areas with cover, hens with broods can reduce the risk of their chicks being depredated.
32

The Effect of Grass Reseeding in Sagebrush Lands on Sage Grouse Populations

Trueblood, Richard W. 01 May 1954 (has links)
The particular purpose of this study was to determine the effects of large-scale sagebrush reseeding projects on sage grouse populations and whether such effects were partly or entirely beneficial, neutral, or detrimental to the survival of such populations. During two seasons of field work, the studies initiated on a short-time basis had the following specific objectives: To compare the utilization by sage grouse of reseeded and non-reseeded lands for the seasonal activities of mating, nesting, raising a brood, fall coveying, and wintering. To compare the utilization by sage grouse of reseeded and non-reseeded lands for daily activities of feeding, watering, resting, hiding, and roosting. To determine fall and winter movements of the grouse in relation to reseeded lands. To determine the food and cover available to grouse on randomly selected sample plots To arrive at an index to food preferences through comparison of stomach analysis and food availability studies. To determine the effect of livestock grazing of reseeded lands on sage grouse. To determine the effect of plant succession on availability of food and cover within reseeded lands.
33

The Greater Sage-grouse in Wyoming: A Technonatural Study

Stubberfield, Alexander Thomas 15 January 2020 (has links)
This dissertation examines the operation of neoliberal environmentality through the instrumentalization of the Greater Sage-grouse (Centrocercus urophasianus) in Wyoming. It treats technological interventions within environmental construction as generating biotic-machinic entanglements termed technonature. I present the formation and operation of the Wyoming Conservation Exchange as a case study of technonatural territorialization connected to global trona and hydrocarbon commodity flows. The theoretical framework elaborates how "the environment" is constructed and governed through tactical instrumental deployments connected to technocratic management allowing economically powerful actors to inscribe their desires within Wyoming's landscape, politics and biota as a function of environmental security related to commodity development. The question motivating this work is "Whose environment is the Environmental Defense Fund defending?" The Greater Sage-grouse has become an object of U.S. Federal environmental governance since the late 1990's. It has experienced significant population declines due to anthropogenic disturbance and habitat loss through industrial action across its range. Wyoming's Sagebrush Steppe contains 37.5% of the remaining range wide population. The grouse was listed as a candidate species under the 1973 U.S. Endangered Species Act triggering responses from Federal, State, and international wildlife management agencies, as well as environmental non-governmental organizations. Wyoming could lose nearly a quarter of its surface should Federal regulations require the designation of critical sage-grouse habitat. Governor Dave Freudenthal signed Executive Order 2008-2 into law in response to the regulatory threat to Wyoming's hydrocarbon and mineral based economy. The grouse, in response was de-listed as a candidate species in 2015 by the U.S. Fish and Wildlife Service. EO 2008-2 established the Wyoming Core Area Strategy as a statewide conservation umbrella and laid the framework for a habitat mitigation economy allowing industrial activity to continue within sage-grouse habitat. This incentivized the Environmental Defense Fund (EDF) to test a market-based instrument – a habitat exchange – within Wyoming. The Greater Sage-grouse is a test species as it is highly sensitive to changes in its environment and this dissertation examines how the habitat mitigation economy advanced by EDF is drawing the grouse into global commodity networks as a territorialization process for global flows of hydrocarbons and minerals. At stake is the ability to write the history of the species, land, and the global environment as EDF develops conservation technologies prioritizing flows critical to the hydrocarbon environment through the technology of the Wyoming Conservation Exchange. / Doctor of Philosophy / The Greater Sage-grouse (Centrocercus urophasianus) entered Euro-American scientific study as early as the Lewis and Clark expedition as they explored the Intermountain region of Western North America. The first thorough scientific study of the sage-grouse in the 20th Century, The Sage Grouse in Wyoming, by Dr. Robert Lansing Patterson included the effects of anthropogenic disturbance on grouse populations. Since the 1952 publication of Patterson's study, Greater Sage-grouse numbers have been declining as the bird loses its home to encroachments such as urbanization, agriculture, grazing, mining, and fossil fuel extraction. The last stronghold of the grouse is the Sagebrush Steppe within Wyoming containing nearly 40% of the remaining population. Known for its flamboyant mating displays, the ground-dwelling avian species has become a political flashpoint in conservation, land management, and environmental circles as its numbers declined steadily since the 1990's due to an accelerating energy boom threatening its habitat. The bird became a threat to extractive industry in Wyoming at the turn of the Millennium as environmentally concerned groups petitioned the U.S. Fish and Wildlife Service (UFWS) to evaluate its populations under the Endangered Species Act (ESA). Nearly a quarter of Wyoming's surface would be strictly policed as critical habitat were the grouse listed as endangered or threatened under the ESA. Wyoming and its partners created the Wyoming Core Area Protection Strategy (CAP) as a wildlife management framework through Executive Order 2008-2. The Wyoming CAP includes the foundation of a habitat mitigation economy allowing industry to trade surface disturbances within critical sage-grouse habitat for modified land purportedly to the benefit of the species. The Nature Conservancy invited the Environmental Defense Fund to form the Wyoming Conservation Exchange – a market-based conservation instrument tailored to trading in habitat mitigation credits. This dissertation studies the Wyoming Conservation Exchange as an instrument connected to larger networks of wildlife management agencies, non-governmental organizations, and mining and fossil fuel interests. It evaluates the effects of the Wyoming Conservation Exchange and the economy it seeks to establish as changing how the environment is managed across the Sagebrush Steppe. Environmental Defense Fund's conservation instrument is reviewed through the economy created for and through the Greater Sage-grouse as an object of environmental governance. Habitat offsetting can, has and will change the physical, and political environment of Wyoming allowing powerful actors to write the rules of how the environment should be managed. As such, this dissertation questions whose environment the Environmental Defense Fund is defending as it explores sage-grouse management within the state.
34

Breeding season habitat use and response to management activities by greater sage-grouse on Sheldon National Wildlife Refuge, Nevada

Davis, Dawn M. 06 June 2002 (has links)
Greater Sage-Grouse (Centrocercus urophasianus) have experienced declines throughout their range over the last 50 years. Long-term declines in sage-grouse abundance in Nevada and Oregon have been attributed to reduced productivity. From 1995-1997, sage-grouse production on Sheldon National Wildlife Refuge (SNWR), Nevada was greater compared to Hart Mountain National Antelope Refuge (HMNAR), Oregon. Specific causes for the difference were unknown. Thus, the objectives were to: 1) Determine sage-grouse breeding season habitat use (especially with regard to wildfire) on SNWR; 2) Evaluate reproductive parameters to discern differences between SNWR and HMNAR; 3) Compare habitat components which may relate to differences in sage-grouse reproductive success on SNWR and HMNAR; and 4) Establish hematological and serum chemistry reference ranges for sage-grouse hens to assess physiological condition. Cover type was important in selection of nest sites at SNWR; however, nest cover did not affect nesting success and nest-site selection was not related to experience. Vegetative characteristics at successful nest sites were similar to unsuccessful nests but nest sites had greater amounts of tall residual grass (���18 cm) and medium height shrub cover (40-80 cm) than at random sites. Broods used areas with greater forb cover than random sites, indicating use was influenced by availability of forbs. Plant communities in wildfire and associated control sites did not differ appreciably in species composition. Although burning had little stimulatory effect on total forb cover 10-12 years post-burn, alteration of the sagebrush community did not limit sage-grouse use for successful nesting and brood-rearing. Fire did not negatively impact arthropod abundance. Differences in habitat use and sage-grouse productivity between SNWR and HMNAR may be related to differences in forb availability. Forb cover was greater at HMNAR than at SNWR for all cover types. Correspondingly, home range size for sage-grouse broods was greater on SNWR than at HMNAR. Nutrient analysis of forbs indicated higher crude protein, potassium, and magnesium levels at HMNAR than at SNWR; however, these nutrients are not likely to be deficient in most sage-grouse diets. Thus sagebrush-steppe communities supporting these forbs likely meet the dietary nutritional requirements of sage-grouse. Although blood calcium and uric acid levels were greater in sage-grouse hens on HMNAR than at SNWR, differences were attributed to capture date. Furthermore, physiological condition did not affect a hen's ability to nest successfully, nor was condition related to a hen's ability to recruit chicks to 1 August. Causes of sage-grouse decline are varied, but ultimately they are habitat based. Comparisons of reproductive parameters and habitat evaluations, combined with sage-grouse physiology data, may provide insight into habitat differences between study areas not previously recognized. Land management practices (e.g., prescribed fire) which recast the balance of native herbaceous species in degraded big sagebrush communities, may be necessary in the restoration of sagebrush-steppe ecosystems, and ultimately, the recovery of sage-grouse populations. / Graduation date: 2003
35

Habitat Selection by Two K-Selected Species: An Application to Bison and Sage Grouse

Kaze, Joshua Taft 01 December 2013 (has links) (PDF)
Population growth for species with long lifespans and low reproductive rates (i.e., K-selected species) is influenced primarily by both survival of adult females and survival of young. Because survival of adults and young is influenced by habitat quality and resource availability, it is important for managers to understand factors that influence habitat selection during the period of reproduction. My thesis contains two chapters addressing this issue for K-selected species in Utah. Chapter one evaluates habitat selection of greater sage-grouse (Centrocercusurophasianus) on Diamond Mountain during the critical nesting and brood-rearing period. Chapter two address selection of birth sites by bison (Bison bison) on Antelope Island, Utah. We collected micro-habitat data for 88 nests and 138 brood locations of greater sage-grouse from 2010-2012 to determine habitat preferences of nesting and brooding sage-grouse. Using random forests modeling techniques, we found that percent sagebrush, percent canopy cover, percent total shrubs, and percent obscurity (Robel pole) best differentiated nest locations from random locations with selection of higher values in each case. We used a 26-day nesting period to determine an average nest survival rate of 0.35 (95% CI = 0.23 – 0.47) for adults and 0.31 (95% CI = 0.14 – 0.50) for juvenile grouse.Brood sites were closer to habitat edges, contained more forbs and less rock than random locations. Average annual adult female survival across the two-year study period was 0.52 (95% CI= 0.38 – 0.65) compared to 0.43 (95% CI= 0.28 – 0.59) for yearlings.Brooding and nesting habitat at use locations on Diamond Mountain met or exceeded published guidelines for everything but forb cover at nest sites. Adult and juvenile survival rates were in line with average values from around the range whereas nest success was on the low end of reported values. For bison, we quantified variables surrounding 35 birth sites and 100 random sites during 2010 and 2011 on Antelope Island State Park. We found females selected birth sites based on landscape attributes such as curvature and elevation, but also distance to anthropogenic features (i.e., human structures such as roads or trails). Models with variables quantifying the surrounding vegetation received no support.Coefficients associated with top models indicated that areas near anthropogenic features had a lower probability of selection as birth sites. Our model predicted 91% of observed birth sites in medium-high or high probability categories. This model of birthing habitat, in cooperation with data of birth timing, provides biologists with a map of high-probability birthing areas and a time of year in which human access to trails or roads could be minimized to reduce conflict between recreation and female bison.
36

Greater sage-grouse habitat selection and use patterns in response to vegetation management practices in northwestern Utah

Graham, Stephanie E 01 May 2013 (has links)
Greater sage-grouse (Centrocercus urophasianus; sage-grouse) currently occupy an estimated 56% of the potential range-wide pre-European settlement habitat. Population declines have been largely attributed to direct habitat loss and fragmentation related to anthropogenic activities that promote wildfires and the subsequent spread of invasive plants. Vegetation manipulations, including the seeding of plant species, such as forage kochia (Bassia prostrata), have been identified as potential strategies to mitigate the risk of wildfire and enhance sage-grouse habitat in areas at risk to wildfires. I evaluated the composition changes that occurred in a lower elevation sagebrush (Artemisia spp.) plant community within the Grouse Creek Watershed in western Box Elder County, Utah, USA, in response to prescribed vegetation manipulations (green-stripping through chain harrowing, juniper mastication, seeding forage kochia, applying Plateau® herbicide) and studied the effect of these changes on sage-grouse habitat-use patterns and vital rates. I monitored 53 radio-collared sage-grouse throughout the Grouse Creek watershed from 2010-2012. Seasonal movements suggested local individual bird adaptations to annual variations in weather and habitat fragmentation. Sage-grouse selected for untreated areas; however, treated areas were used to expand the size of the lek. Untreated areas exhibited a higher percent composition of shrubs compared to areas that were chain harrowed to prepare a seedbed. Sage-grouse nest success and adult male survival rates during this study were relatively low compared to range-wide population estimates. Nest predation was higher for nests located closer to roads. The forage kochia seeded in the firebreaks emerged the season after seeding (2011). Using microhistological techniques, I detected small quantities of forage kochia in sage-grouse fecal pellets. Nutrient analysis confirmed that forage kochia samples collected from the sites exhibited a high protein content and low secondary metabolite content, similar to black sagebrush (Artemisia nova). Although greenstripping with forage kochia in lower elevation sagebrush communities may prove to be a beneficial technique for protecting rangelands from wildfire and provide a dietary source for wildlife, site preparation should be conducted to minimize the impact on existing sagebrush canopy cover habitats. Long-term monitoring should be implemented to determine extended effects of greenstripping treatments on sagebrush habitat and sage-grouse vital rates. Although individual sage-grouse demonstrated local adaptations to fragmentation and seasonal variations in weather, increased fragmentation and climate change in this part of the Great Basin may increase meta-population extirpation risks inhabiting lower elevation sagebrush areas in the Grouse Creek Watershed.
37

Winter Ecology of Common Ravens in Southern Wyoming and the Effects of Raven Removal on Greater Sage-Grouse Populations

Peebles, Luke W. 01 May 2015 (has links)
My research focused on common raven (Corvus corax; hereafter raven) winter ecology and removal, and how raven removal aids Greater sage-grouse (Centrocerus urophasiansu; hereafter sage-grouse) populations. Raven winter ecology in the western US has not been described in detail. I researched raven use of landfills for foraging and raven use of anthropogenic structures for roosting, as well as dispersal of ravens in the spring. In all 22% of radio-marked ravens (n=73) used landfills during the day, and 68%(n=73) roosted at anthropogenic roost sites during the evening. Correlations between landfill and roost counts of ravens were stronger (0.4>r<0.7) when the distance between these sites was <15 km, and smaller (r<0.3) when this distance >20 km. In the spring, ravens dispersed, on average, 38 km from landfills where they were caught. Large congregations of ravens at a few sites in winter may present opportunities to initiate raven population reduction methods to alleviate later problems. I analyzed raven survival and behaviour when USDA/APHIS Wildlife Services (WS) removed ravens using DRC-1339 during winter months. The number of ravens killed annually was 7-34% of the local population. Ravens did not avoid landfills, yet they switched roosts more frequently after an application of the toxicant. Raven removal improves sage-grouse nest success; however, data were not available to examine how raven removal improves sage-grouse abundance. I analyzed changes in raven density with regard to WS removal, and then related these changes with changes in sage-grouse lek counts the following year. Raven densities decreased by 50% from 2008-2014 where WS conducted removal programs. Sage-grouse lek counts improved in area where WS lowered raven abundance, in comparison to areas farther away, during the latter half of the study (2013-2015), when WS removal efforts intensified. Thereafter, a 10% decline in raven abundance was associated with a 2% increase in sage-grouse lek counts. Overall, ravens in souther Wyoming used anthropogenic resources during the winter, and removal of ravens at these locations, combined with removal in the spring, minimally impacted raven populations annually and was associated with increases in sage-grouse abundance.
38

Using Remotely Piloted Aircraft and Infrared Technology to Detect and Monitor Greater Sage-Grouse

Thompson, Thomas R. 01 May 2018 (has links)
In wildlife management, using cutting edge technology and science to monitor greater sage-grouse (Centrocercus urophasianus; sage-grouse) populations, enables land managers to better assess the impact of their management decisions. Having precise counts of sage-grouse lek attendance, and specifically male lek attendance, is an important metric used to evaluate population status and response to conservation actions (Gifford et.al, 2013, Dahlgren et al., 2016). Leks are seasonal breeding sites where males perform a ritualistic courtship dance for females. Our case study examined if a Remotely Piloted Aircraft (RPA) was effective in detecting, and counting, sage-grouse during the lek season (early March to late April). More specifically, this research used a Forward-Looking Infrared (FLIR) camera (a thermal camera) to detect sage-grouse and determine body temperatures of individual sage-grouse to determine if temperature data can be used to identify displaying male sage-grouse. These images can be used to document the activity and behavior of sage-grouse and can be revisited at future times to document changes in bird numbers as well as perform additional statistical analyses. We conducted 5 flights and on a per-flight basis, we identified an average of 4.4 displaying males, 13.4 non-displaying males, and 5.6 female sage-grouse. We found that the average size and average maximum temperature of the three sage-grouse categories differed where females were smaller with an average body size of 325 cm2, an average maximum temperature of 14.6 C ̊, and a smaller average thermal range of 2.47 C ̊. Non-displaying male body size was approximately 488 cm2, with a maximum average temperature of 17.2 C ̊, and an average thermal range of 4.66C ̊. Displaying male body size was the largest at approximately 655 cm2, an average maximum temperature of 27.5C ̊, with the largest average range of 12.39C ̊. Our study demonstrates that RPA and infrared technology can be used to conduct accurate sage-grouse lek attendance counts. Further, results of this study will also provide a guideline for the use of RPA’s to monitor sage-grouse and other lekking species.
39

Sagebrush Ecology of Parker Mountain, Utah

Dulfon, Nathan E. 01 May 2016 (has links)
Parker Mountain, is located in south central Utah, it consists of 153 780 ha of high elevation rangelands dominated by black sagebrush (Artemisia nova A. Nelson), and mountain big sagebrush (Artemisia tridentata Nutt. subsp. vaseyana [Rybd.] Beetle) communities. Sagebrush obligate species including greater sage-grouse (Centrocercus urophasianus) depend on these vegetation communities throughout the year. Parker Mountain is owned and managed by Utah School and Institutional Trust Lands Administration, Bureau of Land Management, and the United States Forest Service. Land management on Parker Mountain include wildlife conservation and providing sustainable ecosystem services such as livestock grazing. My research described the species composition of the black sagebrush communities, evaluated the long-term vegetation responses to two mechanical (Dixie harrow/Lawson aerator) and one chemical treatment (tebuthiuron), and herbaceous biomass responses to tebuthiuron treatments in mountain big sagebrush communities on Parker Mountain. My results indicated when black sagebrush canopy cover was <20%, average grass canopy cover was highest (13%). When black sagebrush canopy cover exceeded 40%, grass canopy cover was lowest (8%). Forb canopy cover was relatively consistent (5%) across black sagebrush communities with >20% canopy cover. Communities with <20% black sagebrush canopy cover had the lowest forb canopy cover. Tebuthiuron reduced mountain big sagebrush percent canopy cover (>9 years), increased grass canopy cover, and increased forb canopy cover more than the two mechanical brush control methods. Tebuthiuron treatments shifted sites from xeric to more mesic plant communities, which resulted in increased percent forb cover required by greater sage-grouse during late-brooding. Herbaceous biomass increased under tebuthiuron treatments in mountain big sagebrush pastures. Tebuthiuron treatments also reduced live sagebrush canopy cover for at least 9 years.
40

The Role of Vegetation Structure, Composition, and Nutrition in Greater Sage-Grouse Ecology in Northwestern Utah

Wing, Brian R. 01 May 2014 (has links)
The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is the largest grouse species in North America and an indicator species for the condition of sagebrush (Artemisia spp.) ecosystems. The Box Elder Sage-Grouse Management Area (SGMA) in northwestern Utah encompasses one of the state’s largest sage-grouse populations. To fill knowledge gaps regarding the population inhabiting the Raft River subunit of the Box Elder SGMA, I captured, radio-marked, and monitored 123 (68 female, 55 male) sage-grouse from January 2012 through December 2013. My purpose was to describe how the seasonal movements, survival, and reproductive rates of this sage-grouse population are effected by small-scale habitat use and breeding season foraging patterns. Sage-grouse in the Raft River subunit have distinct winter and summer ranges, and some travelled long distances annually. Survival rates were similar to other Utah populations and range-wide averages. Nest and brood success rates were above range-wide averages and those reported in the adjacent Grouse Creek subunit of the same SGMA. Sage-grouse in the study area selected habitats with specific vegetation characteristics to fit their seasonal needs. Sage-grouse use sites differed from random sites with greater forb height, grass height, and shrub height and cover. Nest success rates were directly related to selected vegetation, as successful nests were located more often under sagebrush and within greater forb height and cover and grass and shrub height than unsuccessful nests. Brood sites were also greater in forb, grass, and shrub height than other use sites. In March and April of 2013, I located radio-marked sage-grouse at flock browse sites to observe their sagebrush diet selection patterns. Lab analyses showed no differences in nutritional quality or chemical composition between browsed sagebrush plants and non-browsed and random plants. However, browsed black sagebrush (A. nova) was lower in protein and higher in chemical content than browsed Wyoming big sagebrush (A. tridentata wyomingensis). Radio-marked females were frequently observed at sites where black sagebrush was browsed, and one individual chemical was considerably more concentrated in browsed plants associated with females that nested successfully. My research provides useful information regarding the seasonal habitat use patterns and vegetation preferences of sage-grouse in the Box Elder SGMA. To conserve the sage-grouse population in northwestern Utah, management actions must protect the seasonal habitats and vegetation that the species depends on for its productivity and survival.

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