Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 121 for “"population trends"”.
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Population trends and ecological community interactions of freshwater mussels
… building a better understanding of mussel population dynamics and the interactions of mussels with other taxa is important to understanding potential impacts on freshwater ecosystems in the era of anthropogenic global environmental change. This thesis addresses three broad questions. First, …
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A study of factors affecting population trends in northwestern Kansas
Digitized by Kansas State University Libraries
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A study of factors affecting population trends in northwestern Kansas
Digitized by Kansas State University Libraries
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Sharp-Tailed Grouse (Tympanuchus phasianellus) Habitat Selection and Population Trends in Saskatchewan
… While the decline in sharp-tailed grouse populations has been variously attributed to habitat loss, degradation, and fragmentation, the major factors affecting population trends remain to be definitively identified. Two areas of importance for research were highlighted by provincial …
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The biology, ecology and population trends of jacopever Helicolenus dactylopterus in South Africa
… The life history, habitat preference and population trends of the species in South Africa were thus investigated. The age, growth, reproductive characteristics and diet were examined from 719 specimens collected from west and south coast trawls. The maximum age estimated was 32 years and …
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Long-term population trends and habitat preferences of waders at Strandfontein wastewater treatment works
… describe long term migrant and residential wader population trends at Strandfontein, and to identify the potential factors which influence local wader abundance. Once identified, these factors are integrated into a management plan that would create ideal wader habitat, and attract larger numbers …
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Malleefowl and anthropogenic change: an integrated analysis of population trends, landscape genetics and movement ecology
… future impacts. The objectives were to assess population trends, investigate landscape genetics, study movement patterns and the influence of habitat variables. These objectives were addressed through a multidisciplinary approach to study discrete Malleefowl populations at study sites located …
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Pteropod shell condition, locomotion, and long-term population trends in the context of ocean acidification and environmental change
… and examining the response of a local pteropod population to environmental change over time. I analyzed shell condition after exposing pteropods to elevated CO2 as well as in natural populations to investigate the sensitivity of the shells of different species to aragonite saturation state (ΩA). …
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Pteropod shell condition, locomotion, and long-term population trends in the context of ocean acidification and environmental change
… and examining the response of a local pteropod population to environmental change over time. I analyzed shell condition after exposing pteropods to elevated CO₂ as well as in natural populations to investigate the sensitivity of the shells of different species to aragonite saturation state …
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Reproduction of coastal birds breeding in the Wadden Sea: variation, influencing factors and monitoring
… the contribution of current breeding success to population trends of single species. The studies were conducted during the mid 1990s and at the beginning of the 2000s investigating six frequent breeding bird species at 17 breeding sites throughout the German part of the Wadden Sea area. In …
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The Effects of Diet and Predation on Nesting Herring Gulls (Larus argentatus) in Pukaskwa National Park
… ecosystem in Pukaskwa National Park. Their populations have declined by 70% over the last 40 years, suggesting changes in the park ecosystem. I assessed herring gull diets and investigated how diet may influence population trends through effects on life-history endpoints. I additionally …
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A Comparison of Wildlife Monitoring Techniques in Riparian Ecosystems of the Western United States
… presence, absence and distribution, relative population abundance, and factors that influence population trends and dynamics. Wildlife camera trapping is the most ideal method to assess mammal species presence, absence, and distribution. Fecal DNA surveying is the most suitable method for …
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Demographic trends in the European Union: political and strategic implications
This thesis analyzes adverse demographic trends in the European Union, including sub-replacement birthrates and increasing median ages. It investigates the implications of these trends for the EU's prospects for becoming a stronger and more influential actor in international affairs. Pressures …
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Genetic, clinical and population priors for brain images
… as observed in medical scans, along with its population trends and genetic predisposition. In most analyses, anatomical information is extracted from images to provide insight into a problem, facilitating understanding of genetic variants, clinical variables and population trends. In contrast, …
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Migratory connectivity and differential patterns of decline in Barn Swallow (Hirundo rustica) in North America: Potential effects of factors on breeding and wintering grounds
Populations of several Neotropical migratory bird species have experienced declines in the recent decades but long-distance migrant aerial insectivores seem to be declining at greater rates than any other group. The Barn Swallow (Hirundo rustica) is a long-distance migrant and an aerial insectivore …
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The population status, breeding success and diet of Subantarctic Skuas two decades after the feral cat eradication on Marion Island
… availability is often the driver behind predator population trends, diet and breeding success. Changes in predator abundance and breeding success represent numerical responses to changes in prey abundance, whereas dietary shifts can be classified as functional responses. Invasive mammals …
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Reorganization of the elementary schools in the Linden Union High School District
… transportation feasible?; (5) What are the population trends?; (6) What barriers affect district reorganization?; (7) Where are the community interest centers?; (8) What reorganization is educationally sound?</p>
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Characterizing African Elephant (<i>Loxodonta Africana</i>) Population Dynamics and Distribution in Botswana
… is globally threatened. Of the total continental population, 37% is found in Botswana, the highest number and density of elephants in Africa. Elephant management in this country remains challenging and complex as the population estimates and trends calculated by government and independent …
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Quantifying national abundance changes of raptors across Botswana using repeat road surveys
… of carnivorous birds experiencing considerable population declines across the globe. Despite these declines, many raptor populations remain poorly monitored across most of their ranges and, as with most biodiversity, this is especially true in developing countries, including most countries …
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