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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.
101

Perspectives on prions : mapping the social landscape around chronic wasting disease on the Canadian prairies

2014 April 1900 (has links)
Social perspectives on natural resources management have become an increasingly valuable part of natural resources management decision making, especially at the policy or governance level. However, due to the range of social contexts that can exist around management questions, not every technique for incorporating stakeholders into management is suited for every management problem. My research examines the social landscape around chronic wasting disease (CWD) management on the Canadian prairies in order to identify a way forward for stakeholder involvement in CWD management. CWD is a prion disease that results in neurodegeneration and death in cervids. CWD has the potential for broad social impact because it infects elk and deer, species which are both hunted and ranched. Furthermore, management and monitoring efforts in free-ranging cervids frequently incorporate hunting activity. Q methodology was used to survey stakeholders in Saskatchewan and Manitoba and synthesize perspectives about stakeholder understanding of CWD as a problem and preferences for potential solutions. The perspectives that emerged emphasized the importance of increasing knowledge about CWD and a generalized trust in government management, coupled with a desire for stakeholder consultation under the auspices of government leadership. I found that CWD management may not be ready for stakeholder spearheaded management activity due to ambivalence and uncertainty among stakeholders, but stakeholder involvement in CWD management can still offer valuable insight for managers. This is especially notable in light of the recent loss of Saskatchewan’s CWD monitoring program.
102

LESSONS FROM SCENARIO PLANNING FOR WILDLIFE MANAGEMENT IN THE SOUTHWEST YUKON

2014 January 1900 (has links)
The southwest Yukon social-ecological system (SES) is marked by complex changes, including a climate induced directionally changing landscape, an increasing shift away from traditional subsistence lifestyles, and changing species composition. The addition of “new” ungulate species through human and non-human introductions has spawned many management questions. This study developed qualitative scenarios through a participatory process, utilizing scientific and traditional knowledge from within the social-ecological system’s local context. The study worked with local management groups to address two main objectives: 1.) Collaboratively envision alternate future scenarios with management groups from which to collaboratively develop management goals for wood bison, elk, and mule deer to cope with the changing social and ecological landscape of the southwest Yukon and 2.) Discover resource managers’ and local stakeholders’ perceptions of scenario planning as a method identify wildlife management goals. A series of three workshops with the Alsek Renewable Resource Council, the Yukon Wood Bison Technical Team, and the Yukon Elk Management Planning Team addressed the first objective, while two surveys addressed the second objective. Major findings included southwest Yukon-specific wildlife management goals and considerations for using scenario planning in a wildlife management context. The scenarios themselves warn of plausible events that might unfold, such as novel disease and pest outbreaks. Several participants mentioned that the value attributed to different species will change based on scenario context. This prompts warnings for wildlife managers not to “shut the door” on a species today that may be highly valuable for solving food security challenges of the future. Findings suggest that one of scenario planning’s most significant contribution is a forum for people to share perspectives and develop trust and understanding of one another. All participants valued the holistic and long-term thinking aspects of scenario planning, seeing it as a complementary tool to enhance existing planning processes. Major resource management plans and/or resource development projects in the future should consider using a scenarios approach to better articulated goals in terms of whole system impacts.
103

The effects of hunting and seral succession upon Vancouver Island black-tailed deer

Smith, Ian Donaldson January 1968 (has links)
The role of seral succession and hunting in the regulation of Vancouver Island black-tailed deer populations (Odocoileus hemionus columbianus, Richardson) was studied from comparison of observed changes in the Northwest Bay herd over the period 1954-1966 with those predicted from a computer simulation of population processes of such a herd. Northwest Bay was chosen because there were accurate logging records since the first cut was made in 1939, and accurate kill records since hunters were first allowed into the area in appreciable numbers in 1954. Previous studies had shown that deer populations increase rapidly after fire and logging, but tend to return to former levels 15 to 20 years later. Indices of range condition were calculated by multiplying the number of square miles of land in certain seral stages by the number of deer per square mile expected to occupy each stage (as determined by previous studies). Over the period 1956-1966 the Northwest Bay area was in decline as deer habitat, while hunting pressure increased. Two independent indices suggested that deer numbers declined over this period, in association with a decline in condition (measured by weight in fall) of the younger age-classes of males. Average weights of the lower age-classes of females followed similar patterns, but the decreases in weight were not significant—perhaps because of inadequate samples. These changes supported the hypothesis that seral succession is the most important long-range determinant of deer numbers, but one expected change (the development of an older average age) was not found. The proportion of 1.5-year-old animals increased and decreased in cyclic fashion over the period 1954-1966, but no consistent trend towards an older or younger age-class structure was observed when the period 1954-1959 was compared with the period 1960-1966. The absence of such a change was attributed to the effects of hunting, which would be expected to produce a younger average age if significant numbers of animals were harvested, and thus counteract the effects of a deteriorating habitat. In the years of heaviest hunting mortality (1962 and 1963 ) hunters probably accounted for 15 per cent of the fall population as a whole, and over 20 per cent of the fall male population. These levels of exploitation apparently resulted in significant declines in numbers of animals after both of these years, which supported the hypothesis that hunting can serve as a regulatory mechanism to maintain numbers within the limits determined by seral succession. Further support for this viewpoint came from the fact that year-to-year fluctuations in numbers, which were apparently great in the period 1954-1962, appeared to be dampened over the last four years of the study—a result which was predicted by computer simulation. A second major direct cause of mortality over the period 1954-1966 was believed to be winter weather. Significant declines in both numbers of animals and condition of males after the 1955-56 winter, which according to temperature and snowfall records was more severe than normal. There is reason to believe that this winter also resulted in disproportionately-high mortality among female fawns and 1.5-year-olds, but sample sizes were too small to permit adequate assessment of this point. A second winter, 1964-65, which was believed to have affected many Vancouver Island deer herds adversely and which was more severe than normal according to temperature and snowfall indices, had negligible effects upon the Northwest Bay deer. This may have been because, by this time, numbers had been reduced by hunting to levels that the area could effectively support even in a severe winter. One paradox was found, however. Hunting patterns resulted in males being shot in proportionately greater numbers than females, and in latter years this difference was apparently great enough to reduce the proportion of adult males. However, no corresponding significant change in the pattern of differences in male and female age-class structure was observed. Computer simulation of Northwest Bay population processes (not including fawns during the first two months of life) indicated that natural mortality from accident, predation, disease and other miscellaneous causes excluding winter loss associated with malnutrition was approximately 10 per cent of the herd every six months. It was concluded that seral succession had been the indirect cause of the decline in numbers of Northwest Bay deer over the period 1954-1966, but that numbers of animals in any year during the period 1954-1961 were dependent upon the severity of the winter, while following this time year-to-year population levels were dependent primarily upon the effects of hunting. / Science, Faculty of / Zoology, Department of / Graduate
104

Seasonal movements of black-tailed deer on northern Vancouver Island

Harestad, Alton Sidney January 1979 (has links)
Columbian black-tailed deer (Qdocoileus hemionug cplumbianus Richardson) were radio-tagged in a deep snowfall region on northern Vancouver Island, British Columbia. These deer were monitored to determine seasonal movements and habitat use. Deer exhibited either resident or migratory movement patterns. Resident deer made seasonal shifts in their home range centres but their seasonal home ranges overlapped. In migratory deer, summer home ranges were separated from both spring and winter home ranges, although their spring and winter home ranges overlapped. Altitudinal migrations occurred by deer moving between high and low elevation habitats. Horizontal migrations occurred by deer moving between a small tributary valley and the main valley. Seasonal movements of black-tailed deer result from habitat selection by deer seasonally moving to more favourable habitats as determined by more available energy and nutrients, and lower risk of predation. The causal differences between vertical and horizontal migrations as well as seasonal shifts in home range centres can be resolved by a model of habitat selection based on these factors. The densities of available digestible dry matter in Amabilis Fir - Twisted Stalk, and Mountain Hemlock - Copperbush associations are comparable with those in the shrub and conifer serai stages. This abundance of deer food in high elevation habitats suggests that forest harvesting in high elevations will not affect deer populations, if their other habitat requirements are met. In areas where forested summer ranges already exist, low elevation logging of Sword Fern - Western Red Cedar, Deer Fern - Western Hemlock, and Western Hemlock - Plagiothecium associations will provide deer with sources of abundant food closer to their winter ranges than the high elevation summer ranges. Use of these food sources may result in only a redistribution and not an increase in the deer population. Logging of Amabilis Fir - Western Hemlock, Salal - Douglas-fir, and Salal - Western Hemlock associations may be detrimental to deer populations because of their need for these habitats during winter. Management policies emphasizing preservation of severe winter range could be detrimental to deer populations. Habitat management for black-tailed deer must include provision of mild winter range as well as severe winter range. Because mild winter range provides deer with greater amounts of available energy and nutrients, it may be as important to the over-winter survival of deer as is severe winter range. The mobility of black-tailed deer and their sensitivity to snow suggest that few deer would be trapped in high elevations by early snowfalls. Corridors joining high and low elevations appear unnecessary to facilitate deer migrations. / Forestry, Faculty of / Graduate
105

Boundaries and Bridges in Rangeland Social-Ecological Systems: Studies of Collaboration, Innovation, and Information Flow

Meredith, Gwendŵr R. 01 December 2019 (has links)
Public rangelands are managed by a mixture of federal, state, and local governments. Often, these groups are charged with managing adjacent lands that are part of the same greater landscape. To do this effectively, communication and collaboration is required. This dissertation examines federal, state, and local agencies’ level of communication through three projects. The first project examined barriers to agencies adopting management tools from each other. I found that individuals within agencies were mainly staying within their own agency when seeking advice, so individuals were not communicating about tools or their findings across agencies. Furthermore, agency policies and fear of being sued restricted individuals’ ability to adopt management tools. The second project studied how land and wildlife managers in Southeastern Utah work together, or not, in managing mule deer populations that migrate to and from land managed by different agencies. I found that managers are working together to manage mule deer populations, but there are only a few individuals that tie everyone together. The third project looked at how federal, state, and local governments work together to rehabilitate lands after a wildfire that burned parts of Southwestern Idaho and Southeastern Oregon. I found that policy decisions at the federal level can heavily impact who works together and when. All three projects revealed that there are still barriers to federal, state, and local governments working together to manage the same landscape. However, the results from this dissertation also highlight opportunities for bridging the gap between agencies and, ultimately, improving management of rangelands.
106

Mule Deer Highway Mortality in Northeastern Utah: An Analysis of Population-Level Impacts and a New Mitigative System

Lehnert, Mark E. 01 May 1996 (has links)
Rerouting highways to accommodate construction of the Jordanelle Reservoir in northeastern Utah caused a dramatic increase in vehicle collisions with mule deer (Odocoileus hemionus). I evaluated the effectiveness of a new system of highway crosswalk structures installed to reduce deer losses and preserve seasonal migrations. In addition, I constructed computer simulation models to investigate how highway mortality has impacted the Jordanelle deer population. The crosswalk system restricted deer crossings to specific, well-marked areas along highways where motorists could anticipate them. Subsequent to installation, mortality declined 42.3% and 36.8% along a four-lane and two-lane highway, respectively. I was unable to statistically demonstrate that observed mortality reductions were a direct result of the crosswalk system. The potential applicability of the structures, however, should not be dismissed. Reduced deer use of the highway right-of-way (ROW), the apparent maintenance of migratory behavior, and observations of animals crossing within crosswalk boundaries indicate the system warrants further testing. Lack of motorist response to crosswalk warning signs, the tendency for foraging deer to wander outside crosswalk boundaries, and the ineffectiveness of ROW escape gates contributed to most treatment area mortalities. I offer design modifications that address these shortcomings. Four years of field data revealed that highway mortality at Jordanelle was inversely density-dependent, removed between 5.6% and 17.4% of the population each year, and disproportionately impacted bucks. I incorporated this information into 3 competing simulation models in which highway losses operated in a strictly additive, partially compensatory, or strictly compensatory manner. The partial compensation model most closely tracked observed population dynamics, suggesting that highway losses were not completely offset by reductions in other mortality sources. Highway mortality apparently worsened a population crash initiated by severe winter conditions, and may be slowing the recovery. The disproportionate loss of bucks along roads altered sex ratios of simulated populations. Mitigative efforts should target road-kill reductions >60% to avoid population declines predicted by the partial compensation model. Annual variation in demographic parameters offset the impacts of highway mortality at high population levels. At low population levels, however, highway mortality was severe enough to drive declining population trends.
107

Competition Dynamics Within Communities of Desert Wildlife at Water Sources

Hall, Lucas Keith 01 June 2016 (has links)
Water is a vital resource for species inhabiting arid and semi-arid regions and can shape the biotic communities that we observe. Because water is considered a limiting resource for many species in desert environments, there is the potential for competitive interactions between species to occur at or around water sources. For this dissertation I tested hypotheses related to resource competition among different species of wildlife in the Great Basin and Mojave Deserts of western Utah. Chapter one evaluated the influence of feral horses (Equus caballus) on patterns of water use by communities of native birds and mammals. Chapter two determined if feral horses competed with pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) for access to water. In chapters one and two, we found evidence that horses compete with native wildlife for water. In chapter one, horses were associated with decreased richness and diversity of native species at water sources. Native species also had fewer visits and spent less time at water sources frequented by horses. In chapter two, we found that pronghorn and mule deer used water sources less often where horse activity was high. There were also significant differences in temporal activity for pronghorn, but not mule deer, at horse-occupied sites versus sites where horses were absent or uncommon. Our results indicated that horses spatially and temporally displaced other species at water sources providing evidence of a negative influence on how communities of native wildlife access a limited resource in an arid environment. Chapter three assessed whether dominant carnivores (coyote (Canis latrans) and bobcat (Lynx rufus)) negatively influenced the spatial use of water sources by the subordinate kit fox (Vulpes macrotis). Our results did not reveal strong negative associations between kit fox visits to water sources and visits by dominant carnivores; in fact, dominant carnivores contributed very little to the use of water by kit foxes. Instead, kit fox visits were more closely associated with habitat features at water sources. Our findings indicate that dominant carnivores are not the primary driver of use of water sources by subordinate carnivores. Chapter four evaluated whether a simulated loss of water due to climate change/increased human use would differentially affect desert bats based on flight morphology and maneuverability. When we experimentally reduced surface area of water sources, larger, less-maneuverable bats experienced a 69% decrease in drinking success and increased competition with smaller, maneuverable bats. Anticipated reductions in the sizes of water sources due to climate change may lead to species with less maneuverability being unable to access water efficiently and facing increased competition from more agile bats.
108

Odocoileus hemionus (hemionus) on the North Rim of the Grand Canyon: A Study of Wildlife Nutrition, Metabolic Response and Interaction of the Herd with the Winter Habitat on the North Kaibab Plateau.

January 2014 (has links)
abstract: A mule deer herd exists on the northern rim of the Grand Canyon, located on the North Kaibab Plateau. Historical references to this indigenous mule deer herd presented reports of periodic population irruption and collapse. Partially funded by the Arizona Game and Fish Department and the Arizona Deer Association, examination of herd nutritional and metabolic status from the Fall 2005 - Spring 2008 was completed at the request of AzGFD and ADA. Habitat analysis included forage micro-histological, protein, and caloric content plus whole blood and plasma assays gauging herd metabolic response. Modelling was completed using best management practices wildlife energy demand calculations and principal component analysis. Forage quality analysis and modelling suggest a sufficient amount of nitrogen (N) available (DPI) to the deer for protein synthesis. Energy analysis (MEI) of forage suggest caloric deficiencies are widely prevalent on the north Kaibab plateau. Principal component analysis integrates forage and metabolic results providing a linear regression model describing the dynamics of forage utilization, energy availability, and forage nitrogen supply with metabolic demand and response of the mule deer herd. Most of the plasma and blood metabolic indicators suggest baseline values for the North Kaibab mule deer. Albumin values are in agreement with albumin values for mule deer in the Southwest. I suggest that the agreed values become a standard for mule deer in the Southwestern U.S. As excess dietary N is converted to a caloric resource, a continual state of under-nutrition exists for the deer upon entering the N. Kaibab winter range. The population is exceeding the nutritional resource plane that the winter habitat provides. Management recommendations include implementation of multiple small-scale habitat rehabilitation efforts over time, including invasive juniper (Juniperous osteosperma) and piñon (Pinus edulis) management, prescribed burning to control big sage (Artemesia tridentata) populations, and reseeding treated areas with a seed mix of native shrubs, grasses and forbs. I recommended that the population size of the North Kaibab deer herd is maintained at the current size with natural selection controlling growth, or the population be artificially reduced through increased hunting opportunities. / Dissertation/Thesis / Ph.D. Environmental Design and Planning 2014
109

Survival of Neonate Mule Deer Fawns in Southern Utah: Effects of Coyote Removal and Synchrony of Parturition

Hall, Jacob Tyler 01 April 2018 (has links)
Mule deer (Odocoileus hemionus) are an iconic species of wildlife, and populations of mule deer across much of the western U.S. have experienced recent fluctuations in size. Factors that affect the survival and subsequent recruitment of juveniles may be the preeminent cause of population fluctuations for mule deer in many areas. Many factors, including habitat loss, extreme weather, intense predation, timing and synchrony of parturition, and competition with other species may be influencing these changes. We studied two potential factors that can influence the survival of neonate mule deer in southern Utah. To better understand how predation affects mule deer, we first implemented a study of the response of mule deer to removal of coyotes in southern Utah. We monitored survival and cause-specific mortality of neonate mule deer in areas where coyotes were removed and where they were not removed. We used multi-model inference within Program MARK and a known-fate model to estimate survival of neonate mule deer in both treatments (removal and non-removal), and to investigate factors potentially influencing survival. Our results indicated that coyote control can decrease mortality and increase survival of neonate mule deer in some situations. Removal of coyotes was most effective when removal efforts occurred for multiple consecutive years, and when control efforts occurred in or near fawning habitat. Second, we examined how synchrony of parturition affects the survival and cause-specific mortality of neonate mule deer. Reproductive synchrony is a strategy that influences the survival of juveniles and the growth of populations. Our objective was to test three possible explanations for the synchrony of parturition in mule deer; 1) pressure of predation on newborns, 2) a hybrid of predation and environmental effects, and 3) weather and food availability. To determine the effects of the timing of parturition on the survival and predator-related mortality of neonate mule deer, we used multi-model inference within Program MARK and a known-fate model. Our results indicated that the timing of parturition influenced survival and predator-related mortality of neonate mule deer. There was a lag between the onset of parturition of mule deer and predation of mule deer by fawns; individuals born close to the onset of parturition had higher survival and lower predator-related mortality than those whose births were delayed relative to the onset of parturition. Since predators selected for neonate mule deer that were born late, predator learning may partially explain reproductive synchrony in mule deer. Environmental factors may have a greater effect than predation on the survival of early-born individuals.
110

Improving Capture Methods for Neonate Ungulates

Turnley, Matthew T. 15 March 2022 (has links)
The capture of neonate ungulates has played an integral role in studies of habitat selection, phenology, survival, and other topics of ecological interest. However, neonates can be difficult for researchers to locate and capture. Neonate ungulates are born in habitats with reduced visibility, frequently spend time in a concealed, prone position, and may display cryptic coloration. In an attempt to improve researchers' likelihood of locating and capturing neonate ungulates, multiple capture methods have been developed. Much remains unknown about biases associated with capture methods and how to further improve capture methods once biases are understood. Our objectives were to determine if opportunistic captures of neonate mule deer (Odocoileus hemionus) bias estimates of litter size (Chapter 1) and to determine when searches for neonate elk (Cervus canadensis) should begin following parturition to maximize likelihood of capture while minimizing disturbance (Chapter 2). To complete our objectives, we analyzed data from 161 litters of mule deer and 55 attempted captures of neonate elk during 2019-2021 in Utah, USA. Estimates of litter size derived from opportunistic captures of mule deer were smaller than estimates derived from movement-based captures or captures completed with the aid of vaginal implant transmitters (VITs). The time elapsed between parturition and when searches were initiated for neonate mule deer did not influence estimates of litter size, but we could only analyze this relationship for VIT-aided captures within approximately 2 days of parturition. Until more data are available, we recommend that estimates of litter size for neonate mule deer be completed using movement-based or VIT-aided captures within approximately 2 days of parturition. When attempting to capture neonate elk, reducing the time elapsed between parturition and when searches were initiated resulted in a decreased search length, decreased distance traveled by the neonate, and increased likelihood of capture. We initiated searches as early as 3.6 hours post-parturition with no evidence of maternal abandonment and probability of capture was near or above 90% when searches were initiated within 10 hours of parturition. We recommend that searches for neonate elk be initiated 3.6-10 hours post-parturition. Future researchers can use utilize our results to perform captures of neonate ungulates that minimize bias, decrease disturbance, increase efficiency, and maximize the likelihood of capture success.

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