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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

Space Use, Resource Selection, and Survival of Reintroduced Bighorn Sheep

Robinson, Rusty Wade 01 August 2017 (has links)
Successful management of bighorn sheep depends on understanding the mechanisms responsible for population growth or decline, habitat selection, and utilization distribution after translocations. We studied a declining population of desert bighorn sheep in the North San Rafael Swell, Utah to determine birthdates of neonates, demographics, limiting factors, population size, probable cause of death, production, and survival. We documented 19 mortalities attributed to a variety of causes including cougar predation (n = 10, 53%), bluetongue virus (n = 2, 11%), reproductive complications (n = 2, 11%), hunter harvest (n = 1, 5%), and unknown (n = 4, 21%). Annual survival of females was 73% (95% CI = 0.55—0.86) in 2012 and 73% (95% CI = 0.55—0.86) in 2013. Adult male survival was 75% in 2012 (95% CI = 0.38—0.94) and 88% (95% CI = 0.50—0.98) in 2013. Disease testing revealed the presence of pneumonia-related pathogens. The population increased from an estimated 127 in 2012 to 139 in 2013 (λ = 1.09). Lamb:ewe ratios were 47:100 in 2012 and 31:100 in 2013. Mean birthing dates were 21 May in 2012 and 20 May in 2013. Spatial separation from domestic sheep and goats, and aggressive harvest of cougars, may have aided in the recovery of this population after disease events. Second, we investigated the timing of parturition and nursery habitat of desert bighorn sheep in the North San Rafael Swell to determine the influence of vegetation, topography, and anthropogenic features on resource selection. We monitored 38 radio-tagged ewes to establish birthing dates. We documented birthdates of 45 lambs. We used collar-generated GPS locations to perform logistic regression within a model-selection framework to differentiate between nursery and random locations (n = 750 for each) based on a suite of covariates. The top model included elevation, slope, ruggedness, aspect, vegetation type, distance to trails, and distance to roads. We used these variables to create a GIS model of nursery habitat for the North San Rafael (desert bighorns) and the Green River Corridor (Rocky Mountain bighorns). Ewes showed preference for steep, north-facing slopes, rugged terrain, lower elevation, and avoidance of roads. Our model provides managers with a map of high probability nursery areas of desert and Rocky Mountain bighorns to aid in conservation planning and mitigate potential conflicts with industry and domestic livestock. Finally, we monitored 127 reintroduced female bighorn sheep in three adjacent restored populations to investigate if the size and overlap of habitat use by augmented bighorns differed from resident bighorns. The size of seasonal ranges for residents was generally larger than augmented females. However, there was a shift in utilization distribution in all three populations after augmentation. Overlap indices between resident and augmented sheep varied by source herd. These data will help managers understand the dynamics of home range expansion and the overlap between provenance groups following augmentations.
32

Behavioral ecology and conservation of large mammals: historical distribution, reintroduction and the effects of fragmented habitat

Gilad, Oranit 15 May 2009 (has links)
Conservation biologists have used reintroduction as a method to reestablish extirpated species in their native habitat. Three important aspects of a successful reintroduction effort include: (1) a habitat suitability study of the reintroduction area, including effects of migration corridors; (2) identification of possible predators of the reintroduced species; and (3) a post-reintroduction assessment including an evaluation of the species' population dynamics. In this study I examine the suitability of Guadalupe Mountains National Park (GUMO) as a reintroduction area for desert bighorn sheep. The study used landscape metrics to compare GUMO to a nearby mountain range that is currently supporting an estimated population of 400 bighorn sheep. This study identified migration corridors for bighorns throughout the region and evaluated mountain lion (a potential predator of bighorn sheep) numbers either residing in or passing through the park between the years 1997 to 2004. Results on the studies in GUMO revealed 15,884 ha of suitable habitat for bighorn sheep and provided evidence of migration routes between GUMO and neighboring mountain ranges. In terms of potential predators, a minimum of 32 resident and/or transient mountain lions occurred in GUMO over a seven year period, and a minimum of 15 cats used the park in 2002. Based on estimates of individual home range of males and females, GUMO should be able to support four to five individuals. The genetic data indicates a high number of transients or perhaps an unstable population of mountain lions that may be the result of intense hunting pressure of cats in Texas. Finally, my study simulates parameters of the population dynamics of a different species, the Arabian oryx that was reintroduced as three separate populations to the Israeli Negev between 1998 and 2005. I simulated population growth and the effect of migration corridors on species persistence. Results suggest that migration corridors are essential for a self-sustaining viable metapopulation under current natality rates. In the event that natality rates increase (as was evident in a reintroduced population of Arabian oryx in Oman), metapopulation can reach viable size with only two of the release sites (open, flat terrain) connected by migration corridors.
33

Behavioral ecology and conservation of large mammals: historical distribution, reintroduction and the effects of fragmented habitat

Gilad, Oranit 15 May 2009 (has links)
Conservation biologists have used reintroduction as a method to reestablish extirpated species in their native habitat. Three important aspects of a successful reintroduction effort include: (1) a habitat suitability study of the reintroduction area, including effects of migration corridors; (2) identification of possible predators of the reintroduced species; and (3) a post-reintroduction assessment including an evaluation of the species' population dynamics. In this study I examine the suitability of Guadalupe Mountains National Park (GUMO) as a reintroduction area for desert bighorn sheep. The study used landscape metrics to compare GUMO to a nearby mountain range that is currently supporting an estimated population of 400 bighorn sheep. This study identified migration corridors for bighorns throughout the region and evaluated mountain lion (a potential predator of bighorn sheep) numbers either residing in or passing through the park between the years 1997 to 2004. Results on the studies in GUMO revealed 15,884 ha of suitable habitat for bighorn sheep and provided evidence of migration routes between GUMO and neighboring mountain ranges. In terms of potential predators, a minimum of 32 resident and/or transient mountain lions occurred in GUMO over a seven year period, and a minimum of 15 cats used the park in 2002. Based on estimates of individual home range of males and females, GUMO should be able to support four to five individuals. The genetic data indicates a high number of transients or perhaps an unstable population of mountain lions that may be the result of intense hunting pressure of cats in Texas. Finally, my study simulates parameters of the population dynamics of a different species, the Arabian oryx that was reintroduced as three separate populations to the Israeli Negev between 1998 and 2005. I simulated population growth and the effect of migration corridors on species persistence. Results suggest that migration corridors are essential for a self-sustaining viable metapopulation under current natality rates. In the event that natality rates increase (as was evident in a reintroduced population of Arabian oryx in Oman), metapopulation can reach viable size with only two of the release sites (open, flat terrain) connected by migration corridors.
34

Structural controls on evaporite paleokarst development : Mississippian Madison Formation, Bighorn Canyon Recreation Area, Wyoming and Montana

Eldam, Nabiel S. 20 July 2012 (has links)
This study provides new insights on the mechanisms that controlled the development of solution-enhanced fractures and suprastratal deformation associated with the Mississippian Madison Sequence IV evaporite paleokarst complex. Based on detailed field mapping utilizing LiDAR, GPS, and field observations, we document a paleostructural high (oriented 145º) associated with the Ancestral Rockies uplift within the study area. One hundred twenty-one sediment-filled, solution-enhanced fractures within the Seq. IV cave roof were mapped and characterized by their dominant fill type (Amsden or Madison) and vertical extent. Spatial analysis reveals minimum spacing of these features occurs in areas uplifted during the Late Paleozoic suggesting a link between paleostructural position and solution feature spacing. Shape analysis of these solution features also supports structural position during the Late Paleozoic acted as a dominant control on fracture morphology: (1) downward tapering and fully penetrative features concentrate in areas that experienced uplift; (2) upward tapering concentrate in areas that were undeformed. Mapping of Seq. IV cave roof strata demonstrates vertical collapse variability exceeds 22 m and fault intensity increases in areas of increased collapse. These findings have significant implications for prediction and characterization of solution-enhanced fractures and suprastratal deformation within evaporite paleokarst systems. / text
35

Evolutionary quantitative genetics and genomics applied to the study of sexually dimorphic traits in wild bighorn sheep (Ovis canadensis)

Poissant, Jocelyn Unknown Date
No description available.
36

Evolutionary quantitative genetics and genomics applied to the study of sexually dimorphic traits in wild bighorn sheep (Ovis canadensis)

Poissant, Jocelyn 06 1900 (has links)
The independent evolution of the sexes may often be constrained if male and female homologous traits share a similar genetic architecture. Thus, cross-sex genetic covariance is assumed to play a key role in the evolution of sexual dimorphism (SD) with consequent impacts on sexual selection, population dynamics and the speciation process. I used quantitative genetics tools to assess the importance of sex-specific genetic variance in facilitating the evolution of body mass and horn size SD in wild bighorn sheep from Ram Mountain, Alberta. I also developed a bighorn sheep genetic linkage map composed of 247 microsatellite markers to gain insights about the genetic architecture of trait variation. Finally, I conducted systematic reviews and meta-analyses of published cross-sex genetic correlations (rMF, a standardized estimate of cross-sex genetic covariance) to test basic hypotheses about the importance of sex-specific genetic variance in the evolution of SD and mechanisms responsible for generating such variance. My results demonstrated that sex-specific genetic variance was present in bighorn sheep and that it likely played an important role in alleviating intralocus sexual conflicts. The quantitative trait locus (QTL) mapping analysis resulted in the identification of numerous loci influencing body mass and horn dimensions, some of which had apparent sex-specific effects. An analysis of 553 rMF estimates recovered from 114 published sources allowed demonstrating that 1) the evolution of SD was generally constrained by positive cross-sex genetic covariance, 2) levels of SD were often sub-optimal, and 3) sex-specific genetic variance was an important mechanism allowing the evolution of SD. In addition, I confirmed the long-standing hypothesis of a general decline in rMF with age. Sexual dimorphism is an important evolutionary phenomenon, but our understanding of its evolution is still limited. After decades of speculation, my research has provided clear empirical evidence for the importance of sex-specific genetic variance in allowing its evolution. / Ecology
37

A history of Fort Duchesne, Utah, and the role of its first commanding officer, Frederick W. Benteen /

Huetter, Robert A. January 1990 (has links)
Thesis (M.A.)--Brigham Young University. Dept. of History. / Includes bibliographical references (leaves 143-146).
38

Alteration of behavior by desert bighorn sheep from human recreation and Desert Bighorn Sheep Survival in Canyonlands National Park: 2002 - 2010

Sproat, Kanalu K. 04 December 2012 (has links) (PDF)
Human encroachment into wilderness areas can influence the persistence of wildlife populations by decreasing and degrading habitat, displacement, and decreasing survival. For bighorn sheep (Ovis canadensis), some human activities are detrimental, causing both physiological stress and habitat abandonment. Between 1979 and 2000, human recreation has increased over 300% in areas occupied by desert bighorn sheep (O. c. nelsonii) in southeastern Utah. We investigated if an increase in human activity in areas used by bighorns affected their behavior. We observed 34 bighorn sheep using focal-animal sampling for >14 hrs to compare time spent grazing and scanning between areas of high and low human use. We identified group size, presence or absence of a lamb, distance to escape terrain, and human use (high versus low) as potential explanatory variables that influenced grazing and scanning times, and created an a priori list of models based on these variables. We used Akaike's Information Criterion adjusted for small sample sizes (AICc) to rank models, and used model selection to find a best approximating model (lowest AICc value) for both behaviors. Desert bighorn sheep spent less time grazing and more time scanning in high human use areas (22% grazing, 29% scanning) than in low human use areas (54% grazing, 8% scanning). Caution should be taken when considering which areas or trails should be opened during these important seasons to minimize and reduce additional stresses to bighorns caused by human activity. Bighorn sheep populations experienced significant declines after European settlement in North America. Today, the primary practice of bighorn sheep conservation is through population restoration and augmentation from remnant source populations. We conducted a 9-year telemetry study for a source population of desert bighorn sheep in Canyonlands National Park, Utah. We captured and collared 58 bighorn sheep from 2002-2009. To estimate annual and seasonal survival, we used known-fate analysis in Program MARK 4.1. We used model selection to test hypotheses for bighorn survival, including sex, age, human use, year, and month, as possible explanatory variables. There were 20 mortalities during the study. Annual survival ranged from 83% - 88% with no significant variation among any of the years. Model selection results showed that the top six models included a temporal variable (e.g. season or month), and carried 92% of the AICc weight. Population persistence for bighorn sheep can be compromised by high levels of predation, habitat fragmentation, and disease transmitted from domestic sheep. We suggest that land managers continue to maintain the separation of domestic sheep from bighorns in CNP. We also recommend that survival studies continue to ensure that future translocation projects do not occur at the expense of the source population.
39

A History of Fort Duchesne, Utah, and the Role of its First Commanding Officer, Frederick W. Benteen

Huetter, Robert A. 01 January 1990 (has links)
This thesis is a study of the events that occurred during the first five months of Fort Duchesne, Utah, between August and December 1886. The primary focus is on Frederick William Benteen, one of the heroes who fought and survived the Battle of the Little Big Horn. The three Ute tribes--Uintah, White River, and Uncompahgne--are also discussed as they pertain to Fort Duchesne.A difficulty arose the first day a site was chosen at Fort Duchesne. Surprisingly, it did not involve the Indians, but the post commander. The central problem is what caused the long delay in building the fort. This study presents several possible theories as to why troops were still billeted in tents during the winter months of December and January. These include Major Benteen's inexperience as a construction engineer commander and his insatiable drinking habit he had acquired.
40

Patterns and Processes in the Dental Evolution of North American Plesiadapiforms and Euprimates from the Late Paleocene and Early Eocene

Schottenstein, Naava Hadassah 01 October 2020 (has links)
No description available.

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