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Conservation of north Australian magpie geese Anseranas semipalmata populations under global change.Traill, Lochran William January 2009 (has links)
The magpie goose (Anseranas semipalmata) is a spectacular and unique waterbird from tropical north Australia and southern New Guinea. Due to recent human persecution, the species has been eliminated from most of its former strongholds in southern and south-eastern Australia – reduced to small conservation-dependent populations through habitat loss, exploitation and drought. Yet, genuine conservation opportunity still exists in northern Australia, in the country's Northern Territory in particular, to maintain viable populations through evidence-based management of wetlands that support the waterbirds and mitigation of the threats posed by global change. Much has been achieved over the last 50 years to understand the ecology and life history of magpie geese, but little has been done to understand important population-level interactions with wetland habitat and the likely outcomes under climate warming, wetland loss to sea level rise, altered competitive interactions among wetland plants, increased frequency and severity of epizootics, and synergies with over-hunting. My review of pathogens and parasites likely to cause morbidity and mass mortality in magpie geese shows that bacterial diseases such as avian cholera and botulism, as well as pathogenic avian influenza viruses, pose the most serious threats. Bacterial diseases in particular are more likely to occur under warmer and wetter conditions, and geese are susceptible to these given large aggregations at favoured nesting and feeding sites. I use a metapopulation model to demonstrate that increased frequency and severity of epizootics will likely force extirpation of geese under current harvest rates across the Northern Territory. Magpie geese are also vulnerable to climate change through dependency on a favoured food plant – the water chestnut (Eleocharis dulcis). As a result of a two-year field programme, I was able to show how birds seasonally migrate and aggregate in response to the availability of this resource and gain body condition following predation on the root tubers of the plants. My geospatial modelling of ocean level inundation of wetlands that support E. dulcis show marginal habitat loss under 1.4 m of sea level rise, and large-scale losses under multi-metre sea level rise, but the current resolution of GIS data do not account for fine-scale saline water intrusion through channel or eroded levees. The population models constructed predict that magpie geese are broadly resilient to change where harvest is tightly regulated, but current harvest rates are unlikely to be sustainable. Given the importance of maintaining viable, connected subpopulations large enough to maintain genetic diversity, and because of the value of magpie geese to Aboriginal Australians as a food source, ongoing monitoring of geese population trends will be essential. Wetland management options include erecting buffers to stop or slow down saltwater intrusion resulting from sea level rise, and implementing a system to monitor annual indigenous harvest. Temporary restrictions on harvest may be necessary following mass mortality events such as epizootics or droughts. Only the careful management of wetlands that support current geese populations, and close monitoring of populations will ensure continued sustainable harvest of geese under global change. Given the cultural and biological significance of this species and the north Australian wetlands that support it, this is a conservation resource we cannot afford to squander. / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Science, 2009
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Predicting waterfowl distribution in the central Canadian arctic using remotely sensed habitat dataConkin, John Alexander 22 February 2011
Knowledge of a species habitat-use patterns, as well as an understanding of the distribution and spatial arrangement of preferred habitat, is essential for developing comprehensive management or conservation plans. This information is absent for many species, especially so for those living or breeding in remote areas. Habitat-use models can assist in delineating specific habitat requirements or preferences of a species. When coupled with geographic information system (GIS) technology, such models are now frequently used to identify important habitats and to better define species distributions.<p>
Recent and persistent warming, widespread contaminant accumulation, and intensifying land use in the arctic heighten the urgent need for better information about spatial distributions and key habitats for northern wildlife. Here, I used aerial survey and corresponding digital land cover data to investigate breeding-ground distributions and landscape-level habitat associations of greater white-fronted geese (Anser albifrons frontalis), small Canada geese (Branta canadensis hutchinsii), tundra swans (Cygnus columbianus), king eiders (Somateria spectabilis), and long-tailed ducks (Clangula hyemalis) in the Queen Maud Gulf Migratory Bird Sanctuary and the Rasmussen Lowlands, Nunavut, Canada.<p>
First, I addressed the sensitivity of inferences about predicting waterfowl presence on the basis of the amounts and configurations of arctic habitat sampled at four scales. Detection and direction of relationships of focal species with land cover covariates often varied when land cover data were analysed at different scales. For instance, patterns of habitat use for a given species at one spatial scale may not necessarily be predicted from patterns arising from measurements taken at other scales. Thus, inference based on species-habitat patterns from some scales may lead to inaccurate depictions of how habitat influences species. Potential variation in species-environment relationships relative to spatial scale needs to be acknowledged by wildlife managers to avoid inappropriate management decisions.<p>
Second, I used bird presence determined during aerial surveys and classified satellite imagery to develop species-habitat models for describing breeding-ground distributions and habitat associations of each focal species. Logistic regression models identified lowland land cover types to be particularly important for the species considered. I used the Receiver Operating Characteristic (ROC) technique and the area under the curve (AUC) metric to evaluate the precision of models, where the AUC is equal to the probability that two randomly selected encounter and non-encounter survey segments will be discriminated as such by the model. In the Queen Maud Gulf, AUC values indicated reasonable model discrimination for white-fronted geese, Canada geese, and tundra swans (i.e, AUC > 0.7). Precision of species-habitat models for king eiders and long-tailed ducks was lower than other species considered, but predict encounters and non-encounters significantly better than the null model. For all species, precision of species-habitat models was lower in the Rasmussen Lowlands than in the Queen Maud Gulf, although discrimination ability remained significantly better than the null model for three of five species (king eider and long-tailed duck models performed no better than the null model here).<p>
Finally, I simulated anticipated environmental change (i.e., climate warming) in the arctic by applying species-habitat models to manipulated land cover data, and then predicted distributional responses of focal species. All species considered in this research exhibited some association to lowland cover types; white-fronted geese, Canada geese, and tundra swans in particular demonstrated strong affinity toward these habitats. Others authors predict lowland cover types to be most affected by warming. Reductions of wet sedge, hummock, and tussock graminoid cover predicted in this simulation, predominantly along the coast of the Queen Maud Gulf study area and in central areas of the Rasmussen Lowlands, suggest that distributions of species dependant on these lowland habitats will be significantly reduced, if predictions about warming and habitat loss prove to be correct.
Research presented here provides evidence that modeling of species distributions using landscape-level habitat data is a tractable method to identify habitat associations, to determine key habitats and regions, and to forecast species responses to environmental changes.
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Predicting waterfowl distribution in the central Canadian arctic using remotely sensed habitat dataConkin, John Alexander 22 February 2011 (has links)
Knowledge of a species habitat-use patterns, as well as an understanding of the distribution and spatial arrangement of preferred habitat, is essential for developing comprehensive management or conservation plans. This information is absent for many species, especially so for those living or breeding in remote areas. Habitat-use models can assist in delineating specific habitat requirements or preferences of a species. When coupled with geographic information system (GIS) technology, such models are now frequently used to identify important habitats and to better define species distributions.<p>
Recent and persistent warming, widespread contaminant accumulation, and intensifying land use in the arctic heighten the urgent need for better information about spatial distributions and key habitats for northern wildlife. Here, I used aerial survey and corresponding digital land cover data to investigate breeding-ground distributions and landscape-level habitat associations of greater white-fronted geese (Anser albifrons frontalis), small Canada geese (Branta canadensis hutchinsii), tundra swans (Cygnus columbianus), king eiders (Somateria spectabilis), and long-tailed ducks (Clangula hyemalis) in the Queen Maud Gulf Migratory Bird Sanctuary and the Rasmussen Lowlands, Nunavut, Canada.<p>
First, I addressed the sensitivity of inferences about predicting waterfowl presence on the basis of the amounts and configurations of arctic habitat sampled at four scales. Detection and direction of relationships of focal species with land cover covariates often varied when land cover data were analysed at different scales. For instance, patterns of habitat use for a given species at one spatial scale may not necessarily be predicted from patterns arising from measurements taken at other scales. Thus, inference based on species-habitat patterns from some scales may lead to inaccurate depictions of how habitat influences species. Potential variation in species-environment relationships relative to spatial scale needs to be acknowledged by wildlife managers to avoid inappropriate management decisions.<p>
Second, I used bird presence determined during aerial surveys and classified satellite imagery to develop species-habitat models for describing breeding-ground distributions and habitat associations of each focal species. Logistic regression models identified lowland land cover types to be particularly important for the species considered. I used the Receiver Operating Characteristic (ROC) technique and the area under the curve (AUC) metric to evaluate the precision of models, where the AUC is equal to the probability that two randomly selected encounter and non-encounter survey segments will be discriminated as such by the model. In the Queen Maud Gulf, AUC values indicated reasonable model discrimination for white-fronted geese, Canada geese, and tundra swans (i.e, AUC > 0.7). Precision of species-habitat models for king eiders and long-tailed ducks was lower than other species considered, but predict encounters and non-encounters significantly better than the null model. For all species, precision of species-habitat models was lower in the Rasmussen Lowlands than in the Queen Maud Gulf, although discrimination ability remained significantly better than the null model for three of five species (king eider and long-tailed duck models performed no better than the null model here).<p>
Finally, I simulated anticipated environmental change (i.e., climate warming) in the arctic by applying species-habitat models to manipulated land cover data, and then predicted distributional responses of focal species. All species considered in this research exhibited some association to lowland cover types; white-fronted geese, Canada geese, and tundra swans in particular demonstrated strong affinity toward these habitats. Others authors predict lowland cover types to be most affected by warming. Reductions of wet sedge, hummock, and tussock graminoid cover predicted in this simulation, predominantly along the coast of the Queen Maud Gulf study area and in central areas of the Rasmussen Lowlands, suggest that distributions of species dependant on these lowland habitats will be significantly reduced, if predictions about warming and habitat loss prove to be correct.
Research presented here provides evidence that modeling of species distributions using landscape-level habitat data is a tractable method to identify habitat associations, to determine key habitats and regions, and to forecast species responses to environmental changes.
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Methane flux from Carex ramenskii on coastal meadows and grazing lawns in western AlaskaLynöe, Kaj January 2017 (has links)
In this study we determined the magnitude of plant mediated CH4 emission (flux) in two vegetation types of Carex ramenskii. The objectives of this paper were to quantify the proportion of CH4 emissions from plant mediated flux and the total flux (plant and soil). This information is needed in order to understand how grazing affects plant mediated CH4 flux. In addition, we differentiated between two vegetation morphs, grazed and ungrazed, and determined the plant mediated CH4 flux for vegetation type. This study was conducted at a field site on the Tutakoke River (61 15’N, 165 30’W) which is located in the coastal region of the Yukon-Kuskokwim Delta. Three replicate plots of the two vegetation morphs of Carex ramenskii were established. Methane flux was measured with a total flux chamber (plant and soil) and a single leaf chamber using a Picarro Cavity Ring-Down Spectroscopy Analyzer (Model G2308, Picarro Inc., Santa Clara, California). Plant density for the two plant types was determined. Temperature measurements were taken and correlated with gas flux. This study found that total net CH4 emissions from Carex ssp. were the same in both vegetation types. This similarity could indicate that plant mediated flux through vegetation is not affected by grazing in the sense that grazing is neither facilitating nor inhibiting plant mediated CH4 flux. The magnitude of plant mediated flux was still greater in the ungrazed meadow type, indicating on both greater facilitation of CH4 flux, and below ground oxygen transport enabling higher rates of CH4 consumption.
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The Goose at Goldie's Milk Bar: The Nature of Human Animal Relationships in Three Modern Literary Fairy Tales.Teasdale, Dion, d.teasdale@yarraranges.vic.gov.au January 2007 (has links)
The Goose at Goldie's Milk Bar is a modern literary fairy tale written in the form of a novel for adult readers. Set in the fictional Australian small country town of Baxters Creek, it tells the story of Goldie Sullivan, an elderly former milk bar proprietor who has an affair with a gigantic cognisant gander. Goldie lives out the back of the town's old milk bar, hiding from the surrounding narrow-minded community, until late one night she witnesses a bolt of lightning strike the bell tower on the nearby church. When she goes to investigate, Goldie finds the body of a large bird buried in the debris and, believing it is an omen, she carries the half-dead bird home on her back. As she rehabilitates the bird, Goldie discovers there is more to the feathered creature than she first thought. The bird, a giant gander blown off course and struck down in the middle of migration, reveals an advanced awareness of humanity and the profound ability to comprehend the sorrow in Goldie's life. Through a shared appreciation of jazz music, Goldie and the goose learn to communicate and a close friendship ensues. Goldie teaches the goose to dance, the pair share baths and the goose moves into Goldie's bedroom. Before too long, Goldie finds herself in the midst of a most indecent affair. Goldie's relationship with the gander unfolds against a backdrop of other unconventional relationships. Kevin Dwyer, the new reporter in town finds himself drawn to the shire maintenance worker, Travis Handley. Real estate agent Alexander Bourke has taken Lynne Fontaine, the chef at the local Chinese restaurant, as his oriental mistress, and recently windowed farmer, Mary Peddley, sets tongues wagging with the one-legged publican, Jack Diamond. The novel uses the human animal narrative to explore the premise that fate is driven by unseen, sometimes magical forces that manifest in inexplicable ways to reveal the hidden truths of people. The writing of the novel has been supported by research conducted for an exegesis titled, The Nature of Human Animal Relationships in Three Modern Literary Fairy Tales. The exegesis identifies and discusses the nature of the central human animal relationships in three novels: Yann Martel's Life of Pi, Peter Hoeg's Woman and the Ape and the writing project, The Goose at Goldie's Milk Bar. The exegesis identifies and discusses the roles and functions the human and animal characters perform in the three novels through a comparative analysis of the narrative theories of early Russian Structuralist, Vladimir Propp. The exegesis also identifies and discusses the types of transformation the human and animal characters undergo, and conducts a comparative analysis of the theories of English academic and fairy tale historian, Jack Zipes. Finally, the exegesis analyses and discusses the multi-dimensional nature of the bonds formed by the human and animal characters and demonstrates how writers of modern literary fairy tales seek to awaken the reader to the possibilities of relationships with animals beyond usual human understanding or experience.
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Waterfowl disturbance : effects of hunting in a coastal ecosystemDenny, Matthew J. H. January 2001 (has links)
No description available.
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Räven predikar för gässen en studie av ett ordspråk i senmedeltida ikonografi /Rodin, Kerstin, January 1983 (has links)
Thesis (doctoral)--Uppsala universitet, 1983. / Summary in English. Includes bibliographical references (p. 110-119).
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Estudo de parâmetros clínicos, imunitários e do proteinograma sérico da vacinação contra a doença de Newcastle em gansos-da-China (Anser cygnoides): pesquisa do estado portador do vírus e sua importância epidemiológicaCampioni, Josie Maria [UNESP] 05 June 2009 (has links) (PDF)
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campioni_jm_me_jabo.pdf: 299949 bytes, checksum: f61e757f800c01b36b0ae99a0fbe3f0f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Parâmetros clínicos, imunitários, proteinograma sérico e epidemiológicos da vacinação em gansos-da-China foram avaliados por três experimentos. Amostras vacinais Ulster 2C, B1 e La Sota do VDN foram utilizadas. A importância epidemiológica e pesquisa do estado de portador do VDN também foram avaliadas. No experimento 1, foram utilizados 120 gansos-da-China de um dia a 60 dias de idade, distribuídos em 4 tratamentos com 30 animais, submetidos a diferentes esquemas imunoprofiláticos. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Após o desafio frente a uma estirpe patogênica do VDN, aos 60 dias de vida das aves, em todos os grupos, realizou-se a extração de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). No experimento 2, foram utilizadas aves SPF conviventes com gansos-da-China inoculados com uma estirpe patogênica do VDN, decorridos seis, 10 e 20 dias da infecção experimental, após a infecção com o VDN, nas duas espécies, empregou-se a técnica do RT-PCR. Observou-se a transmissão de vírus patogênico (VDN) dos gansos-da- China para as aves SPF conviventes decorridos até 14 dias da infecção experimental com este patógeno, o que vem realçar a importância do ganso-da-China como fonte potencial de infecção de VDN para aves domésticas No experimento 3, foram determinadas as concentrações séricas das proteínas totais, albumina e globulinas das aves vacinadas e não vacinadas contra a doença de Newcastle. Notou-se que aos 42 dias de idade, de forma geral, os gansos vacinados com as estirpes Ulster 2C, B1 e Lasota apresentaram diferença de forma significativa em relação ao grupo controle para as concentrações séricas de albumina, especialmente o grupo vacinado com a estirpe LaSota. / The clinical, epidemiological, immunological parameters and the serum proteinogram of vaccination in Chinese geese were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the NDV were used. In experiment 1, 120 one-day-old Chinese geese were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged Chinese geese were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 20 days after experimental infection. The vaccinated groups of Chinese geese did not present any genetic material of virus in the RT-PCR. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the Chinese geese. In experiment 2, SPF chickens housed with Chinese geese which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days. In experiment 3, the serum proteinogram showed significantly differences for albumin concentrations between the vaccinated and the control group at 42 days of age, especially the birds vaccinated with LaSota strain.
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Marginalia of the Geese Book: Inside and Outside the BordersJanuary 2013 (has links)
abstract: The early-16th-century manuscript commonly known as the Geese Book (New York, Morgan Library, M. 905) contains the entire Mass liturgy sung by the boys choir of the parish church of St. Lorenz in Nuremberg, Germany prior to the Reformation. This thesis addresses the location and function of the sometimes enigmatic marginalia and the decorated or historiated initials in this large two-volume gradual. The paper begins with an analytical case study of a scene within the margins in which a wild woman, wielding a club, confronts a female dragon who has taken a child. Subsequently the size, subject matter, and physical positioning of the illuminations and decorations within the book and on its pages are examined with respect to the gradual's liturgical contents. It is hoped that through such methods, new conversations may begin as to the roles that marginalia and decoration may play within the multiple organizational schemes within a musical text of this kind. / Dissertation/Thesis / M.A. Art History 2013
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Biotic interactions and vegetation management on coastal meadowsNiemelä, M. (Marika) 12 May 2009 (has links)
Abstract
Conservation of rare habitats and species are central elements in the management of semi-natural grasslands of high biodiversity. Understanding the impacts of various abiotic and biotic interactions and management methods on threatened species is fundamental to their conservation. In the present study, effects of competition, plant parasitism, grazing and mowing were studied at the community level in Bothnian Bay coastal meadows and in greenhouse. This was the first time when the impacts of various biotic interactions on the critically endangered creeping alkali grass (Puccinellia phryganodes) have been explored in detail in one of its rare occurrences in the boreal vegetation zone in Europe. In addition, questions related to ecological and economical sustainability of cattle grazing on coastal meadows were examined.
Puccinellia phryganodes was found to suffer severely from competition with taller graminoids. Simulated and actual grazing by greylag goose, Anser anser, as well as infection by a hemiparasitic plant, Odontites litoralis, were found to indirectly benefit P. phryganodes by decreasing the competitive advantage of its competitors. In spite of the relatively intensive grazing by greylag goose in the field, P. phryganodes experienced a drastic decrease during four years in the grazed experimental quadrats and simultaneously the proportion of the taller graminoids increased substantially. Primary succession of coastal meadow vegetation was found to progress rapidly and continuous formation of suitable open habitats is therefore crucial for the subordinate species. Mowing was found to be an effective management method for some threatened plant species in coastal meadows, but not for P. phryganodes, which would probably benefit more, for example, from livestock grazing. Both lightly and rather intensively managed large open meadows could provide optimal habitats for the critically endangered lesser white fronted goose (Anser erythropus) as well as for the greylag goose.
The relatively low and variable yield of the coastal meadow vegetation compared to that of cultivated grasslands sets limits how management by cattle grazing can be implemented. Key factors for both the biodiversity management and livestock production in coastal meadows are timing of the grazing season, intensity of grazing and selection of suitable types of animals.
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