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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.
21

Psychological and Geographic Components of Acceptance for Black Bears in Ohio

Zajac, Ryan Michael 14 September 2010 (has links)
No description available.
22

GENETIC NONINVASIVE CAPTURE-RECAPTURE TECHNIQUES TO MANAGE POLAR BEARS: A PILOT STUDY

Harris, Christopher Matthew 24 December 2010 (has links)
Global polar bear (Ursus maritimus) population numbers are expected to decline steadily over the next 50 years. A noninvasive genetic survey of polar bear numbers may be a useful addition to traditional aerial capture mark recapture (CMR) surveys undertaken throughout the Canadian polar bear population. We attempted a pilot study of noninvasive genetic survey techniques in M’Clintock Channel between May-June 2006-2009. Throughout the survey, we compared our values to the most recent (CMR) survey, conducted by Taylor et al. (2006) between March-June 1998-2000 where 133 cubs, sub-adults and adults were tagged. A total population size of 300 bears was estimated from this aerial CMR survey (Taylor et al. 2006). We found noninvasive sampling stations are sufficient for the capture of a large amount of data on individual bears in an area. Across 4 years, we collected a total of 300 hair samples, and found between 59 and 82 individual bears entered our sampling stations, depending on the stringency of our identification parameters. We estimated genotyping error from duplicated samples, and found this was low (range: 0%-6%), but large enough to not be ignored. There appeared to be a discrepancy between the capture ratio of male adult bears; the CMR survey (1998-2000) captured 25% male bears, while we estimated approximately 64% of our captured bears were male. We felt the most likely explanation of this result is that our traps have a sex bias. However, further research is required to confirm this hypothesis. On the whole, our methods are very important for the management of polar bears, but more research must be done before it can be fully implemented. / Thesis (Master, Biology) -- Queen's University, 2010-12-23 15:35:50.16
23

Biometric analysis and aversive conditioning of black bears in southern West Virginia

Weaver, Harley Wayne. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains vi, 56 p. : ill., maps. Includes abstract. Includes bibliographical references.
24

Bear ceremonialism in the northern hemisphere ...

Hallowell, A. Irving January 1926 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1926. / Bibliography: p. 163-175.
25

Nuisance black bear, Ursus americanus, behaviour in central Ontario

Landriault, Lynn J., January 1998 (has links) (PDF)
Thesis (M.S.)--Laurentian University, 1998. / Includes bibliographical references.
26

Management of brown bears (Ursus arctos) in Europe

Klenzendorf, Sybille A. 16 July 1997 (has links)
Successful conservation of brown bears (Ursus arctos) in Europe is associated with public acceptance of damages caused by bears. Recent increases in sheep depredation and beehive damage in central Austria resulted in the deaths of two bears there. Since bear numbers are low in most European populations, alternatives to the elimination of problem bears associated with damage incidents must be sought. The events described above led to the formation of the Bear Management Group responsible for designing a management plan for Austria that will outline procedures for dealing with bear damage and conservation strategies. This study provides an overview of the magnitude and seasonal patterns of brown bear damage in Romania, Italy, Slovenia, Norway, Sweden, and Austria. It also illustrates how bears are managed in European countries by comparing different management strategies for dealing with brown bear damage, describing how bear management is organized, determining which organizations are involved, and explaining which duties these fulfill. Bear damage data were obtained from interviews with wildlife managers, hunters, and farmers in Romania, Italy, Slovenia, Norway, Sweden, and Austria, and from official records of their bear management agencies. Most damage incidents involved sheep and beehives in all countries. All countries offered a more or less well functioning damage compensation program to farmers. Conservation success, especially for small bear populations, seemed to be related to a good compensation program and reducing damage to livestock and property. Possible improvements of management strategies to reduce damage and increase conservation success in theses countries were discussed The second part of this study was the assessment of the organizational structure of different bear management programs in Europe. Brown bear management in Europe included a broad spectrum of goals, ranging from no protection, to regulated hunting, to total protection. In each country, different organizations were involved in bear management, including private and governmental organizations. For each study country, I outlined which organizations were involved in bear management, determined if a management plan existed,described if and how hunting and damage compensation were structured, explained how each country dealt with problem bears, and finally, detailed what kind of management problems each country encountered. I tried to find management patterns for bear management in Europe, including advantages and disadvantages of each approach and their effectiveness within the countries they were applied. Methods included a content analysis of interviews with wildlife managers, farmers, and local people in each country.Results showed that two general types of management approaches could be identified. Romania, Sweden and Southern Slovenia took a conservationist approach, which was characterized by economic use of their bear population. All of these countries had viable bear populations. Romania and Southern Slovenia included an additional characteristic of feeding bears, which could be viewed as a utilitarian management scheme. The second management approach, which was classified as the preservationist approach, was observed in Norway, Italy, Northern Slovenia, and Austria. This management strategy was characterized by year-long protection of bears, low population numbers, and no feeding of bears. Further results of management differences in problem bear management, damage compensation, public education, and effectiveness of management approaches were summarized. The study provides a reference on bear management strategies in Europe. / Master of Science
27

Mezinárodněprávní ochrana mořských savců / Protection of marine mammals under International Law

Hloušek, Michal January 2012 (has links)
The present thesis begins with a brief overview of some of the most important international, mainly global conventions relevant to the protection of biological diversity in its entierety. Subsequent chapters then deal with some species or higher taxons of marine mammals, in particular with cetaceans, polar bears and pinnipeds. The aim was not only to analyse relevant international conventions, but also to discuss some interesting and precise questions that complete and form the conservation regime.
28

Use of Clearcut Habitats by Black Bears in the Pacific Northwest

Barber, Kim R. 01 May 1983 (has links)
Patterns of vegetation use by black bears (Ursus americanus) on Long Island, Washington were documented using radio-telemetry in 1973-74 and 1980-81. Secondary succession altered the vegetative compostion of clearcut areas through this time, reducing the areas dominated by productive brush species by nearly 50%. Seasonal food habits, consisted primarily of grasses and forbs in spring (den emergence-May) and flowers and fruits of shrub species in summer (June-September) and fall (October-den entrance). Bears selected for clearcuts (5-21 years of age) over all other vegetation types for feeding but preferred areas dominated by large trees when inactive during both the day and night. Inactivity in clearcut areas occurred most frequently in clearcuts offering the greatest amount of horizontal cover. Although preferred in all seasons, clearcuts received the greatest use during the summer months when flowers and fruits of shrubs species were most abundant. Tidelands and meadows were used more in the spring than during other seasons and conifer stands received the greatest proportionate use in spring and fall. Old growth timber (200 +years of age) was used similarly to mature second growth. Adult males were less influenced than other classes of bears by availability of horizontal cover and proximity of cover provided by adjacent vegetation types when feeding in clearcut areas. Adult females with cubs fed in timber stands and clearcuts with abundant horizontal cover more than other bears and generally remained in close proximity to bordering timber stands when feeding in clearcuts. Subadults, as well as adult females with cubs, appeared to use available habitats in a manner that allowed them to avoid other bears. Areas in large timber stands that were long distances from clearcuts were used by bears more during the 1980-81 phase of the study, apparently because of the increased competition for declining resources in clearcut areas. Home ranges of the adult females present during both phases of the study were similar in both size and location.
29

Examing the Dynamic Relationship Between Climate Change and Tourism: A Case Study of Churchill's Polar Bear Viewing Industry

D'Souza, Jamie 03 October 2019 (has links)
The purpose of this thesis research was to examine the dynamic relationship between climate change and tourism, with a direct focus on Churchill, Manitoba’s polar bear viewing industry. This unique tourism industry and the polar bears it depends on, are experiencing the negative effects of climate change due to warmer temperatures and melting sea ice, which significantly impacts the health, appearance, and prevalence of polar bears on display for tourists. Not only is this tourism industry affected by climate change, it also contributes to the ongoing changes of climatic conditions. This is due to the dependence of fossil fuel energy used for transportation, accommodation, and activities which directly contributes to the release of greenhouse gas emissions and thus to global climate change. Emissions from tourism has increased by 3% over the last 10 years, largely as a result of the accessibility and affordability of air travel, the most energy intensive form of transportation (Lenzen et al., 2018; UNWTO-UNEP-WMO, 2008). It has been suggested that in response to the increase in the demand to travel, the tourism industry should take a leadership role to reduce their total greenhouse gas emissions in an effort to decrease the impact of climate change. In this study, a visitor survey was conducted during four weeks of Churchill’s 2018 polar bear viewing season (October 16 to November 16). The aim of the survey was to: 1) estimate greenhouse gas emissions from polar bear viewing tourists and the polar bear viewing industry; 2) identify tourists’ awareness of the impacts of climate change (to and from tourism activities); 3) understand tourist’s climate-related travel motivations, and 4) identify tourists’ opinions on climate change mitigation strategies. Visitor surveys were hand- distributed at the Churchill Northern Studies Centre and at the Churchill Airport to tourists who had participated on a polar bear viewing tour. Surveys were analyzed and compared with the results from similar studies (Dawson et al., 2010 and Groulx, 2015) to identify the changing trends in greenhouse gas emissions, travel motivations, tourists’ knowledge of climate change, and acceptance of climate change mitigation strategies. Similar to trends observed 10 years ago, emissions from polar bear viewing tourists are 3-34 times higher than the average global tourist experience. Tourists’ awareness about climate change has stayed relatively consistent, despite the topic of climate change having received increased attention globally. Tourists recognize that climate change is happening and that it is human induced however, there is still a lack of understanding of how air travel is a contributor to climatic change. Although briefly mentioned in some participant’s responses, the main motivation was not to see a polar bear before it disappeared from the wild. The majority of tourists identified they were traveling to Churchill simply for the opportunity to see a polar bear. Additional motivators were photography, the Northern Lights, and for the opportunity to see other Arctic animals. The climate change mitigation strategies that tourists believed to be the most effective to reduce emissions were educational programs and transportation alternatives (such as taking the train- which was not an option at the time of study due to a rail line shutdown). This research contributes to the existing knowledge about tourism and climate change and provides a current analysis of Churchill’s polar bear viewing industry, enabling a comparison between findings from another study conducted over ten years ago. This research also makes conclusions about climate change mitigation strategies that might be effective for Churchill’s tourism industry to reduce their impact on the environment.
30

Stress Physiology of Bears: Cortisol Dynamics and Identification of Novel Serum Proteins

Chow, Brian Andrew January 2013 (has links)
There is a need to understand how free-ranging animals respond and adapt to stress. However, little is currently known regarding the physiologic adaptations to stress in bears, and there are few tools available to wildlife managers to assess the health and stress status of free-ranging animals, including ursids. The hypothalamus-pituitary-adrenal (HPA) axis plays major roles in the physiological adaptation to stress, leading to the increased secretion of glucocorticoids (e.g. cortisol in most mammals) that mediate adaptive changes in physiology and behaviour. The vast majority of glucocorticoids are bound to its primary carrier protein, corticosteroid-binding globulin (CBG), in most animals, and only the unbound fraction is bioavailable. Thus, CBG plays a major role in modulating glucocorticoid dynamics, and this protein must be characterized to build a more complete understanding of the adaptive role that the HPA axis plays in mitigating stress in bears. The overall objective of this thesis was to characterize the HPA axis activity and CBG levels in bears, and develop tools targeted towards the monitoring of the health and stress status of American black bear (Ursus americanus), grizzly bear (U. arctos), and polar bear (U. maritimus). The binding characteristics of cortisol to CBG in bears were studied via saturation binding experiments, and this information was used to estimate free cortisol concentrations based on CBG concentrations. To quantify CBG concentrations in bears, an enzyme-linked immunosorbent assay (ELISA) was developed. Grizzly bear CBG cDNA was cloned and sequenced, and an antibody was developed against a peptide sequence of the deduced amino acid sequence. The antibody showed good cross-reactivity against black, grizzly, and polar bear CBG, and the ELISA based on this antibody found differences in the mean CBG levels between species. Using this data, free cortisol levels were estimated, and mean levels were elevated in polar bears relative to black and grizzly bears. Having developed these tools, the roles that corticosteroid-binding globulin (CBG) and bioavailable cortisol played in the physiological adaptation to major life history traits and environmental challenges faced by ursids were investigated. Importantly, CBG was not modulated by the acute stress of capture and handling, despite the large differences in the magnitude of acute cortisol responses that are induced by these methods, suggesting that CBG levels may reflect the chronic health and stress status of bears. Altogether, there were few changes in CBG levels throughout much of the annual life cycle of bears, implying that CBG does not play a major adaptive role in the life history traits of bears and, instead, metabolic and environmental factors may be the key modulators of cortisol dynamics. However, CBG was not significantly associated with our measures of dietary patterns and nutrition, including body condition, seasonal dietary patterns, and fasting. The majority of the observed variation in the levels of this protein in bears remains unexplained. However, stress-induced free cortisol levels were negatively associated with urea to creatinine ratio (an indicator of dietary protein content and fasting status in grizzly and polar bears, respectively) and positively associated with lactation in hibernating black bears, suggesting that the variation in adrenal function may be playing an important role in the adaptation to adverse environmental conditions and/or metabolic stress in bears. In addition to serum cortisol dynamics, other proteins were also hypothesized to play adaptive roles in maintaining the hibernating phenotype in bears. Changes in the serum proteome during hibernation in black bears were assessed as a means to discover novel proteins that may be indicative of metabolic stress in bears. The serum proteomes of active and hibernating black bears were compared and analyzed for significant changes by two-dimensional electrophoresis and tandem mass spectrometry. Proteins involved with immune-related function were significantly altered during hibernation, leading to the proposal that the serum protein changes are essential for maintaining immune competence, wound healing, and bone structure. Altogether, this thesis developed a method to quantify CBG and estimated free cortisol concentrations in bears, and characterized their roles in the physiological adaptations associated with the major life history traits and environmental challenges faced by ursids. Also, novel serum proteins were identified as potential markers of immune function and health status in bears. These tools may be tremendously useful for wildlife managers and conservationists in determining how chronic stressors, including anthropogenic activities and climate change, may impact the stress and health performances of individual and populations of free-ranging bears.

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