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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.
11

THE BIOLOGY AND MANAGEMENT OF BRUCELLOSIS IN YELLOWSTONE BISON

Treanor, John Joseph 01 January 2012 (has links)
Disease management along the boundaries of wildlife reserves is a growing conservation problem worldwide, as infected wildlife can migrate outside protected areas and pose a threat to livestock and human health. The bison Bison bison population in Yellowstone National Park has long been infected with Brucella abortus, the bacterium causing bovine brucellosis. Concern over migratory bison transmitting B. abortus to cattle herds on lands adjacent to Yellowstone has led to proposals for bison vaccination. Model simulations suggest that vaccination is unlikely to eradicate B. abortus from Yellowstone bison but could be an effective tool for reducing the level of infection and eliminating unpopular management practices such as lethal culling. The culling of Yellowstone bison to reduce the risk of brucellosis transmission to cattle is negatively affecting long-term bison conservation because of difficulties in diagnosing actively infected animals. Age-specific serology and B. abortus culture assays from slaughtered bison were used to develop a diagnostic tool to estimate whether particular animals are infective. Findings suggest that active B. abortus infection is age-dependent, which allows true infection probabilities to be estimated based on age and quantitative diagnostic tests. Active brucellosis infection was associated with below-average nutritional condition, with the intensity of B. abortus infection being influenced by seasonal reductions in dietary protein and energy. The reproductive strategy of Yellowstone bison is linked with the seasonal availability of food, which increases bison fitness but may have consequences for B. abortus infection. Seasonal food restriction may also influence the ability of vaccinated bison to recall protective immune responses when later exposed to B. abortus. The rate of fat metabolism was an important factor influencing cell-mediated responses. Thus, individual variation and the seasonal availability of food may reduce vaccine efficacy when vaccination is applied at the population level. Consequently, effective management practices will require a diverse range of integrated methods, which include maintaining separation of livestock and wildlife, managing habitat to reduce brucellosis transmission, and reducing disease prevalence in wildlife. The long-term success of these management practices will depend on sound science and support of the stakeholders involved.
12

Sustaining a conservation legacy? an in depth perspective on the interagency bison management plan and the potential for collaboration /

Brininstool, Jason Alan. January 2010 (has links)
Thesis (MS)--University of Montana, 2010. / Contents viewed on April 9, 2010. Title from author supplied metadata. Includes bibliographical references.
13

Change in deciduous woody vegetation, implications of increased willow (Salix spp.) growth for bird species diversity, and willow species composition in and around Yellowstone National Park's Northern range

Baril, Lisa Marie. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Andrew J. Hansen. Includes bibliographical references.
14

Population genetics of Synehococcus species inhabiting the Mushroom Spring microbial mat, Yellowstone National Park

Melendrez, Melanie Crystal. January 2010 (has links) (PDF)
Thesis (PhD)--Montana State University--Bozeman, 2010. / Typescript. Chairperson, Graduate Committee: David M. Ward. Includes bibliographical references.
15

Geochemistry of Inkpot Spring, Sulphur Creek-Sevenmile Hole area, Yellowstone caldera, Wyoming

Andersen, Allen K. January 2010 (has links) (PDF)
Thesis (M.S. in geology)--Washington State University, May 2010. / Title from PDF title page (viewed on May 21, 2010). "School of Earth and Environmental Sciences." Includes bibliographical references.
16

A Trophic State Analysis of Lakes in Yellowstone National Park

Melcher, Anthony Alexander 20 March 2013 (has links) (PDF)
Eutrophication is of interest in the field of water quality. Eutrophic lakes, when used as sources for drinking water, can cause problems during the treatment process, for example algae blooms can clog filters, requiring more water and energy to be used during the cleaning and backwashing of the filters. Excess nutrient loading and eutrophication can also harm fish and aquatic life habitats. Certain species of algae and cyanobacteria can be toxic to humans as well. Since 1998, Dr. A. Woodruff Miller has collected water samples from 46 lakes and ponds in Yellowstone National Park. The Carlson Trophic State Index, the Vollenweider Model, the Larsen Mercier Model, the Burns Trophic Level Index, and the Naumann Trophic Scale were then used to assign each lake or pond to a trophic state classification (Oligotrophic, Mesotrophic, Eutrophic, and Hyper-Eutrophic). Of the 46 total lakes and ponds that have been tested over the past 14 years, five lakes are classified as slightly oligotrophic, implying that the waters are relatively clear and free from nutrient pollution. Of the 46 lakes, 19 are classified as slightly mesotrophic, mesotrophic, or strongly mesotrophic. These classifications imply that the waters are moderately clear and contain some nutrient pollution. Of the 46 lakes, 14 are classified as slightly eutrophic, eutrophic, or strongly eutrophic. This implies that the waters have high turbidity and nutrient content. Of the 46 lakes, 8 are classified as slightly hyper-eutrophic or hyper-eutrophic. These lakes are noticeable for their high algae content with very high nutrient content. These classifications are based on the most recent year sampled.
17

Changes in Microbial Communities and Geochemical Energy Supplies Across the Photosynthetic Fringe of Hot Spring Outflows in Yellowstone National Park

January 2018 (has links)
abstract: Utilizing both 16S and 18S rRNA sequencing alongside energetic calculations from geochemical measurements offers a bridged perspective of prokaryotic and eukaryotic community diversities and their relationships to geochemical diversity. Yellowstone National Park hot spring outflows from varied geochemical compositions, ranging in pH from < 2 to > 9 and in temperature from < 30°C to > 90°C, were sampled across the photosynthetic fringe, a transition in these outflows from exclusively chemosynthetic microbial communities to those that include photosynthesis. Illumina sequencing was performed to document the diversity of both prokaryotes and eukaryotes above, at, and below the photosynthetic fringe of twelve hot spring systems. Additionally, field measurements of dissolved oxygen, ferrous iron, and total sulfide were combined with laboratory analyses of sulfate, nitrate, total ammonium, dissolved inorganic carbon, dissolved methane, dissolved hydrogen, and dissolved carbon monoxide were used to calculate the available energy from 58 potential metabolisms. Results were ranked to identify those that yield the most energy according to the geochemical conditions of each system. Of the 46 samples taken across twelve systems, all showed the greatest energy yields using oxygen as the main electron acceptor, followed by nitrate. On the other hand, ammonium or ammonia, depending on pH, showed the greatest energy yields as an electron donor, followed by H2S or HS-. While some sequenced taxa reflect potential biotic participants in the sulfur cycle of these hot spring systems, many sample locations that yield the most energy from ammonium/ammonia oxidation have low relative abundances of known ammonium/ammonia oxidizers, indicating potentially untapped sources of chemotrophic energy or perhaps poorly understood metabolic capabilities of cultured chemotrophs. / Dissertation/Thesis / Masters Thesis Geological Sciences 2018
18

From reformations to progressive reforms paradigmatic influences on wildlife policy in Yellowstone National Park /

Turney, Elaine C. Prange. January 2007 (has links) (PDF)
Thesis (Ph.D.)--Texas Christian University, 2007. / Title from dissertation title page (viewed Dec. 10, 2007). Includes abstract. Includes bibliographical references.
19

From reformations to progressive reforms paradigmatic influences on wildlife policy in Yellowstone National Park /

Turney, Elaine C. Prange. January 1900 (has links) (PDF)
Thesis (Ph. D.)--Texas Christian University, 2007. / Includes bibliographical references (leaves 258-279). Also available online as a PDF file.
20

Park visitors and the natural soundscape : winter experience dimensions in yellowstone

Saxen, Shelley Walker. January 2008 (has links) (PDF)
Thesis (Ph.D.) --University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on May 15, 2009. ETD number: etd-12112008-123204. Author supplied keywords: natural sounds ; recreation ; visitor experiences ; national park policy ; soundscape policy ; soundscape management ; winter visitor experiences ; wildland recreation. Includes bibliographical references.

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