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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

Sensitivity of high-resolution satellite sensor imagery to regenerating forest age and site preparation for wildlife habitat analysis

Wunderle, Ame Leontina 11 April 2006 (has links)
In west-central Alberta increased landscape fragmentation has lead to increased human use, having negative effects on wildlife such as the grizzly bear (<i>Ursus arctos</i> L.). Recently, grizzly bears in the Foothills Model Forest were found to select clear cuts of different age ranges as habitat and selected or avoided certain clear cuts depending on the site preparation process employed. Satellite remote sensing offers a practical and cost-effective method by which cut areas, their age, and site preparation activities can be quantified. This thesis examines the utility of spectral reflectance of SPOT-5 pansharpened imagery (2.5m spatial resolution) to identify and map 44 regenerating stands sampled in August 2005. Using object based classification with the Normalized Difference Moisture Index (NDMI), green, and short wave infrared (SWIR) bands, 90% accuracy can be achieved in the detection of forest disturbance. Forest structural parameters were used to calculate the structural complexity index (SCI), the first loading of a principal components analysis. The NDMI, first-order standard deviation and second-order correlation texture measures were better able to explain differences in SCI among the 44 forest stands (R2=0.74). The best window size for the texture measures was 5x5, indicating that this is a measure only detectable at a very high spatial resolution. Age classes of these cut blocks were analysed using linear discriminant analysis and best separated (82.5%) with the SWIR and green spectral bands, second order correlation under a 25x25 window, and the predicted SCI. Site preparation was best classified (90.9%) using the NDMI and homogeneity texture under a 5x5 window. Future applications from this research include the selection of high probability grizzly habitat for high spatial resolution imagery acquisition for detailed mapping initiatives.
32

Foraging ecology of brown bears in the Mackenzie Delta region, NWT

Barker, Oliver Unknown Date
No description available.
33

Foraging ecology of brown bears in the Mackenzie Delta region, NWT

Barker, Oliver 06 1900 (has links)
The Mackenzie Delta region, NWT, has a short growing season and highly seasonal climate, and brown bears (Ursus arctos) there face many challenges obtaining their nutritional requirements. Consumption of meat by brown bears is linked to increases in population density, fecundity, growth and body size. I examined the use of Arctic ground squirrels (Urocitellus parryii), and broad whitefish (Coregonus nasus) as meat sources by Mackenzie Delta brown bears. As a preliminary step, I built an Arctic ground squirrel habitat model, using field-surveyed ground squirrel burrow locations. Using this model, I examined bears selection for Arctic ground squirrel habitat as a population, by sex and as individuals, and linked this to results of stable isotope analysis and site investigations. Bears showed little evidence of Arctic ground squirrel use at the population and sex level, but some individual bears appeared to prey heavily on ground squirrels, particularly during hyperphagia. I also described observations of a brown bear using broad whitefish in autumn, and used telemetry locations to show that other bears may also feed heavily on broad whitefish during hyperphagia. My research provides prey-specific evidence for intrapopulation niche variation among Mackenzie Delta brown bears. / Ecology
34

En osynlig gräns : En komparativ ekokritisk undersökning av Blackfish och Grizzly Man / An Invisible Borderline : A Comparative Ecocritical Study of Blackfish and Grizzly Man

Blid, Arild January 2023 (has links)
This thesis conducts a comparative and ecocritical examination of Blackfish and Grizzly Man, two nature documentary films dealing with separate cases of human fatalities caused by wild animals. The aim was to show how nature and non-human animals as well as the relationship between humans/civilization and non-human animals/nature are represented in the films. Additionally, the effects of the representations of non-human animals on a viewer are also examined. For examining representations, the main theoretical frameworks used were: Frans De Waal’s understanding of the concepts of animalcentric and anthropocentric anthropomorphism, and Hillevi Ganetz’s understanding and use of the concept of natursyn (english: view on nature), meaning cultural interpretations of nature, which divides into three views: beautiful, sublime and picturesque. For the additional aim, the concepts of trans-species empathy and false-intimacy were used, the former via Alexa Weik von Mossner’s understanding and use, the latter via Derek Bousé’s. Essentially, the related concepts refer to the human ability to engage emotionally with non-human characters.  What the results show is that both Grizzly Man and Blackfish have ambivalent attitudes toward nature. In both Grizzly Man and Blackfish there are signs of different kinds of anthropomorphism. In terms of natursyn, Grizzly Man consists of a picturesque and a sublime view, articulated verbally and visually, whereas Blackfish consists of a beautiful and a picturesque view, articulated verbally, visually and sonically. The thesis also shows that the representations of orcas as human-like and close-ups of orcas with physical injuries in Blackfish have the potential of creating trans-species empathy. In Grizzly Man, Werner Herzog’s indifferent conception of nature, proclaimed through spoken narration as close-ups of a bear face are shown, discourages the potential effects of such imagery, namely false intimacy.
35

An evaluation of hair cortisol concentration as a potential biomarker of long-term stress in free-ranging grizzly bears (Ursus arctos), polar bears (Ursus maritimus), and caribou (Rangifer tarandus sp.)

2013 October 1900 (has links)
Human-caused ecological change negatively affects the sustainability of many wildlife populations but may be especially challenging for large carnivores and ungulates. Long-term physiological stress may be an important mechanism linking ecological change with impaired health and reduced population performance in these groups. The determination of hair cortisol concentration (HCC) has recently demonstrated potential as a biomarker of long-term stress in humans and domestic animals, and may also represent a practical technique for use in free-ranging wildlife. The objectives of this research program were to: 1) develop and apply an accurate and reliable method for measuring cortisol levels in hair collected opportunistically or remotely from free-ranging grizzly bears (Ursus arctos), polar bears (Ursus maritimus), and caribou (Rangifer tarandus sp.), and 2) to evaluate the utility of HCC as a biomarker of long-term stress (and thus potentially useful conservation tool) in these threatened species. An enzyme-immunoassay (EIA) based technique for measuring HCC in non-human primates was successfully modified for use with small quantities (5-100 mg) of hair representative of samples which may be obtained through opportunistic (e.g. hunting, research captures, archives) or remote (e.g. barb wire snagging) methods in each species. HCC was determined in 151 free-ranging grizzly bears from Alberta, Canada (mean 2.84 pg/mg, range 0.62-43.33 pg/mg); 185 free-ranging polar bears from southern Hudson Bay, Canada (mean 0.48 pg/mg range, 0.16-2.26 pg/mg); in 12 captive Alaskan caribou (R. t. granti) (mean 2.31 pg/mg, range, 1.57-3.86 pg/mg) and 12 captive reindeer (R .t. tarandus) (mean 2.88 pg/mg, range 2.21-3.40 pg/mg) injected either with adrenocorticotropic hormone (ACTH) or saline; and in 94 free-ranging caribou (R. t. groenlandicus) from West Greenland (mean 2.21 pg/mg, range 0.60-6.90 pg/mg). Factors influencing HCC in each species were then explored including: 1) technical considerations for the prudent use of HCC analysis and 2) potential relationships between HCC, biological traits, health, and prevailing environmental conditions. Evidence revealed in this study suggests that, with further research, this technique may show potential as a practical conservation tool for use in free-ranging grizzly bear, polar bear, and caribou populations.
36

Factors affecting persistent organic pollutant (POP) accumulation in British Columbia grizzly bears (Ursus arctos horribilis)

Christensen, Jennie R 24 April 2008 (has links)
This thesis characterizes major factors influencing the accumulation of polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides, and polybrominated diphenyl ethers (PBDEs), in grizzly bears. Dietary differences among grizzly bears have significant implications for contaminant concentrations and patterns. While salmon-eating bears were dominated by lipophilic PCBs, OC pesticides, and lower-brominated PBDEs, non-salmon-eating bears were dominated by the more volatile PCBs and OC pesticides and higher-brominated PBDEs (e.g. BDE-209). Overall, the ocean-salmon-bear pathway appeared to preferentially select for those contaminants with an intermediate log Kow ~6.5, with salmon delivering up to 70% of OC pesticides, 85% of PBDEs and 90% of PCBs to grizzly bears. Fat utilization by grizzly bears during hibernation results in significant contaminant concentration increases in residual fat (“concentration effect”). Overall, total PCBs increased by 2.21 times from pre- to post-hibernation, and total PBDEs by 1.58 times. Interestingly, the patterns of the two distinct pre-hibernation grizzly bear feeding ecologies (salmon- and non-salmon-eating) converged during hibernation, suggesting that shared metabolic capacities drive POP patterns during hibernation. Relative to salmon, grizzly bears have extremely low biomagnification factors (BMFs) for PCBs (0.147), compared to other marine mammals. Low BMF values were a result of >90% depuration (loss) of PCBs through contaminant metabolism and excretion. The results suggest that grizzly bears only metabolize PCB congeners with meta- and para- vicinal hydrogen (H) atoms, suggesting that they have active cytochrome (CYP) P450 2B/3A-like metabolic enzymes. However, congeners structurally resistant to metabolic biotransformation, and those with ortho- and meta- vicinal H atoms, were not readily metabolized, but rather were lost through excretion. This was evidenced by a significant relationship between total retention (Rtotal) of those congeners and log Kow, as well as a lack of change in that relationship during hibernation. Vegetation and the terrestrial food web were dominated by PBDEs and volatile OC pesticides and PCBs, while salmon and the marine food web were dominated by lipophilic PCBs and OC pesticides, mirroring patterns in grizzly bears within their respective food web. Following consumption of these various foods by the grizzly bears, fecal material closely resembled food in contaminant pattern, suggesting that many of the contaminants may go unabsorbed. While previous work identified major factors (e.g. age, sex, diet) influencing POP behaviour in wildlife and food webs, this research highlights the need to refine our ideas about those factors in order to better assess chemical health risk in wildlife by considering: 1) individual differences in feeding behaviour; 2) integrated dietary histories (temporal changes); 3) unique biological traits affecting POP fate; 4) modes of POP loss other than metabolism; 5) selection of the most recalcitrant congener for more robust analysis of POP behaviour; 6) use of non-invasive techniques to study diet and POP exposure; and, 7) tissue residue guidelines underestimate health risks. Our results also suggest that PBDEs show POP-type characteristics as defined under the Stockholm Convention, and thus should be regulated.
37

Spatial analysis of factors influencing long-term stress and health of grizzly bears (Ursus arctos) in Alberta, Canada

Bourbonnais, Mathieu Louis 04 September 2013 (has links)
A primary focus of wildlife research is to understand how habitat conditions and human activities impact the health of wild animals. External factors, both natural and anthropogenic that impact the ability of an animal to acquire food and build energy reserves have important implications for reproductive success, avoidance of predators, and the ability to withstand disease, and periods of food scarcity. In the analyses presented here, I quantify the impacts of habitat quality and anthropogenic disturbance on indicators of health for individuals in a threatened grizzly bear population in Alberta, Canada. The first analysis relates spatial patterns of hair cortisol concentrations, a promising indicator of long-term stress in mammals, measured from 304 grizzly bears to a variety of continuous environmental variables representative of habitat quality (e.g., crown closure, landcover, and vegetation productivity), topographic conditions (e.g., elevation and terrain ruggedness), and anthropogenic disturbances (e.g., roads, forest harvest blocks, and oil and gas well-sites). Hair cortisol concentration point data were integrated with continuous variables by creating a stress surface for male and female bears using kernel density estimation validated through bootstrapping. The relationships between hair cortisol concentrations for males and females and environmental variables were quantified using random forests, and landscape scale stress levels for both genders was predicted based on observed relationships. Low female stress levels were found to correspond with regions with high levels of anthropogenic disturbance and activity. High female stress levels were associated primarily with high-elevation parks and protected areas. Conversely, low male stress levels were found to correspond with parks and protected areas and spatially limited moderate to high stress levels were found in regions with greater anthropogenic disturbance. Of particular concern for conservation is the observed relationship between low female stress and sink habitats which have high mortality rates and high energetic costs. Extending the first analysis, the second portion of this research examined the impacts of scale-specific habitat selection and relationships between biology, habitat quality, and anthropogenic disturbance on body condition in 85 grizzly bears represented using a body condition index. Habitat quality and anthropogenic variables were represented at multiple scales using isopleths of a utilization distribution calculated using kernel density estimation for each bear. Several hypotheses regarding the influence of biology, habitat quality, and anthropogenic disturbance on body condition quantified using linear mixed-effects models were evaluated at each habitat selection scale using the small sample Aikake Information Criterion. Biological factors were influential at all scales as males had higher body condition than females, and body condition increased with age for both genders. At the scale of most concentrated habitat selection, the biology and habitat quality hypothesis had the greatest support and had a positive effect on body condition. A component of biology, the influence of long-term stress, which had a negative impact on body condition, was most pronounced within the biology and habitat quality hypothesis at this scale. As the scale of habitat selection was represented more broadly, support for the biology and anthropogenic disturbance hypothesis increased. Anthropogenic variables of particular importance were distance decay to roads, density of secondary linear features, and density of forest harvest areas which had a negative relationship with body condition. Management efforts aimed to promote landscape conditions beneficial to grizzly bear health should focus on promoting habitat quality in core habitat and limiting anthropogenic disturbance within larger grizzly bear home ranges. / Graduate / 0768 / 0463 / 0478 / mathieub@uvic.ca
38

Analysis of Habitat Fragmentation and Ecosystem Connectivity within The Castle Parks, Alberta, Canada

Beaver, Breanna, beaver January 2017 (has links)
No description available.
39

Werner Herzog em busca da compreensão humana

Leão, Rita de Cássia da Silva 18 May 2015 (has links)
Made available in DSpace on 2016-04-25T20:21:26Z (GMT). No. of bitstreams: 1 Rita de Cassia da Silva Leao.pdf: 5297903 bytes, checksum: 365d1ce161ffb73142a6ebc13ab0e302 (MD5) Previous issue date: 2015-05-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / All movie-making has an anthropological character, as it is as open-ended as humankind itself. The works of Werner Herzog run parallel with fundamental anthropology, which seeks to understand the process of penetration of man into the world and the inseparable process of penetration of the world into man. The first movie that is analyzed, Wodaabe: Herdsman of the Sun, deals with love of beauty among beings who feel despised by neighboring peoples. The second, Grizzly Man, is about a man who wanted to be a bear, as he could not stand living among humans. The third, The Cave of Forgotten Dreams, tells us how humankind dreamed 32 thousand years ago; how it projected its double on cave walls and small statues. Paintings and statues feature at the same time a penchant for both the fantastic and the reality of shapes and forms. It is not Herzog´s movie settings or themes which are anthropological; it is his view of the world and his way of making movies, which transmutes real into imaginary, and imaginary into real / Todo cinema contém um caráter antropológico, por ser aberto como a própria humanidade. A obra de Werner Herzog é contigua à antropologia fundamental, que busca compreender o processo de penetração do homem no mundo e o processo inseparável de penetração do mundo no homem. O primeiro filme analisado, Wodaabe: Os pastores do sol, trata do amor à beleza entre seres que se sentem desprezados pelos povos vizinhos. O segundo, O homem urso, de um humano que queria ser urso e não suportava o mundo dos humanos. O terceiro, A caverna dos sonhos esquecidos, conta como sonhava a humanidade há 32 mil anos, como projetava seu duplo nas paredes das cavernas e nas pequenas estátuas. Nas pinturas e estátuas estão presentes, ao mesmo tempo, uma tendência para o fantástico e para a realidade das formas. Não são os locais de filmagem e tampouco os temas de Herzog que são antropológicos, mas sim a sua visão de mundo e o modo de fazer cinema, que transmuta o real em imaginário e o imaginário em real
40

Werner Herzog em busca da compreensão humana

Leão, Rita de Cássia da Silva 18 May 2015 (has links)
Made available in DSpace on 2016-04-26T14:55:24Z (GMT). No. of bitstreams: 1 Rita de Cassia da Silva Leao.pdf: 5297903 bytes, checksum: 365d1ce161ffb73142a6ebc13ab0e302 (MD5) Previous issue date: 2015-05-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / All movie-making has an anthropological character, as it is as open-ended as humankind itself. The works of Werner Herzog run parallel with fundamental anthropology, which seeks to understand the process of penetration of man into the world and the inseparable process of penetration of the world into man. The first movie that is analyzed, Wodaabe: Herdsman of the Sun, deals with love of beauty among beings who feel despised by neighboring peoples. The second, Grizzly Man, is about a man who wanted to be a bear, as he could not stand living among humans. The third, The Cave of Forgotten Dreams, tells us how humankind dreamed 32 thousand years ago; how it projected its double on cave walls and small statues. Paintings and statues feature at the same time a penchant for both the fantastic and the reality of shapes and forms. It is not Herzog´s movie settings or themes which are anthropological; it is his view of the world and his way of making movies, which transmutes real into imaginary, and imaginary into real / Todo cinema contém um caráter antropológico, por ser aberto como a própria humanidade. A obra de Werner Herzog é contigua à antropologia fundamental, que busca compreender o processo de penetração do homem no mundo e o processo inseparável de penetração do mundo no homem. O primeiro filme analisado, Wodaabe: Os pastores do sol, trata do amor à beleza entre seres que se sentem desprezados pelos povos vizinhos. O segundo, O homem urso, de um humano que queria ser urso e não suportava o mundo dos humanos. O terceiro, A caverna dos sonhos esquecidos, conta como sonhava a humanidade há 32 mil anos, como projetava seu duplo nas paredes das cavernas e nas pequenas estátuas. Nas pinturas e estátuas estão presentes, ao mesmo tempo, uma tendência para o fantástico e para a realidade das formas. Não são os locais de filmagem e tampouco os temas de Herzog que são antropológicos, mas sim a sua visão de mundo e o modo de fazer cinema, que transmuta o real em imaginário e o imaginário em real

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