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1	Pathogenicity of viral hemorrhagic septicemia virus IVb in walleye (Sander vitreus) Grice, Jessica 04 May 2012 (has links) Recently, viral hemorrhagic septicemia virus (VHSV IVb) was associated with several walleye (Sander vitreus) mortality events in the Great Lakes. To examine the effects of route, strain-variation and temperature, walleye were experimentally infected with VHSV IVb using intraperitoneal (i.p.)-injection (102-108 pfu/fish) and immersion (w.; 1.4 x 107 virions mL-1). Walleye were relatively resistant to experimental infection with VHSV IVb, regardless of route or water temperature. High cumulative mortality (64-100%) and severe gross lesions associated with VHSV-IVb infection were only evident in fish i.p.-injected with 108 pfu at 12°C, which had mild to moderate, multifocal necrosis of several tissues including the gill and heart. There were significant differences in mortality between four walleye strains following i.p.-infection. Viral antigen was found in both i.p. and w.-exposed walleye using immunohistochemistry, mostly within the gill and skin epithelium of w.-exposed fish. VHSV IVb was detected in walleye tissues from 6-21 d post-infection using RT-qPCR. / Great Lakes Fisheries Commission and NSERC Sander vitreus
2	Écologie politique d'ensemencements de dorés jaunes au réservoir Baskatong, Québec Calvé-Genest, Alexis 25 April 2013 (has links) Résumé: La dégradation environnementale s'explique de diverses façons selon les théories anthropologiques. L'approche structuraliste récente pose les schèmes mentaux des ontologies humaine comme facteur responsable possible. L'approche expériencielle pose l'éloignement entre l'être humain et la nature comme cause potentielle. L'approche proposant l'imposition d'une idéologie hautement technologique et moderne sur des savoirs locaux en est une autre. Ces trois approches sont utilisées pour analyser les données d'une recherche de terrain centrée sur des ensemencements de doré jaunes au réservoir Baskatong. Les caractéristiques d'un texte d'écologie politiques sous-tendent l'analyse. La compétitivité entre groupes humains ressort comme caractéristique incontournable d'une analyse de la situation, mieux représentée par la troisième approche et un texte en écologie politique. /// Abstract: Environmental degradation is explained through approaches varying according to anthropological theories. The recent structuralist approach poses different mental schemes of human ontologies as potentially responsible. The experiential approach poses a gap between humans and nature as a potential cause. Another approach proposes the imposition of a highly modernistic and technological ideology over local knowledges as explanation. These three approaches are used to analyze field data focussed on walleye stocking at the Baskatong reservoir. The characteristics of a political ecology text overarch the analysis. Results show competition between human groups as an unavoidable characteristic of the analysis, better represented in the third approach and political ecology. Anthropologie Politique Doré jaune Doré Jaune Baskatong Québec Ensemencement Écologie Poisson Pêche Sander vitreus Sander Vitreus Réservoir Fishing Angling Sportive Sports Political Ecology Structualisme Tourisme Règlements
3	Écologie politique d'ensemencements de dorés jaunes au réservoir Baskatong, Québec Calvé-Genest, Alexis January 2013 (has links) Résumé: La dégradation environnementale s'explique de diverses façons selon les théories anthropologiques. L'approche structuraliste récente pose les schèmes mentaux des ontologies humaine comme facteur responsable possible. L'approche expériencielle pose l'éloignement entre l'être humain et la nature comme cause potentielle. L'approche proposant l'imposition d'une idéologie hautement technologique et moderne sur des savoirs locaux en est une autre. Ces trois approches sont utilisées pour analyser les données d'une recherche de terrain centrée sur des ensemencements de doré jaunes au réservoir Baskatong. Les caractéristiques d'un texte d'écologie politiques sous-tendent l'analyse. La compétitivité entre groupes humains ressort comme caractéristique incontournable d'une analyse de la situation, mieux représentée par la troisième approche et un texte en écologie politique. /// Abstract: Environmental degradation is explained through approaches varying according to anthropological theories. The recent structuralist approach poses different mental schemes of human ontologies as potentially responsible. The experiential approach poses a gap between humans and nature as a potential cause. Another approach proposes the imposition of a highly modernistic and technological ideology over local knowledges as explanation. These three approaches are used to analyze field data focussed on walleye stocking at the Baskatong reservoir. The characteristics of a political ecology text overarch the analysis. Results show competition between human groups as an unavoidable characteristic of the analysis, better represented in the third approach and political ecology. Anthropologie Politique Doré jaune Doré Jaune Baskatong Québec Ensemencement Écologie Poisson Pêche Sander vitreus Sander Vitreus Réservoir Fishing Angling Sportive Sports Political Ecology Structualisme Tourisme Règlements
4	Distribution and Status of Native Walleye (<i>Sander Vitreus</i>) Stocks in West Virginia Zipfel, Katherine J. January 2006 (has links) No description available. native walleye walleye <i>Sander vitreus</i> walleye microsatellites
5	Temporal and Spatial Genetic Consistency of Walleye (<i>Sander vitreus</i>) Spawning Groups Banda, Jo Ann January 2011 (has links) No description available. Biology Conservation Ecology Environmental Science Genetics Natural Resource Management walleye microsatellite population genetics Lake Erie Great Lakes Sander vitreus stock structure
6	Permeability improvement of Norway spruce wood with the white rot fungus Physisporinus vitreus / Verbesserung der Permeabilität von Fichtenholz mit dem Weißfäulepilz Physisporinus vitreus Lehringer, Christian 28 January 2011 (has links) No description available. 000 Allgemeines Wissenschaft Forest Sciences and Forest Ecology Permeabilität Fichte Weißfäulepilz Physisporinus vitreus Biotechnologie Modifikation Holzeigenschaft Tüpfel Zellwand Delignifizierung Selektivität Permeability Norway spruce white rot Physisporinus vitreus biotechnology modification wood property bordered pit cellwall delignification selectivity 48.46 YXA 000: Holz Holzeigenschaften {Forstbenutzung}
7	Life History, Maternal Quality and the Dynamics of Harvested Fish Stocks Venturelli, Paul Anthony 03 March 2010 (has links) Knowledge of offspring production (recruitment) is fundamental to understanding and forecasting the dynamics of a population. In this thesis, I focus on two demographic characteristics of fish stocks that are important to recruitment: population density and age structure. First, populations produce more recruits at low density, but quantifying this response has proven difficult. Using data from hundreds of populations of walleye (Sander vitreus), an economically important freshwater fish, I demonstrate that the growing-degree-day metric (a temperature index) is better than age at explaining variation in density-dependent growth and maturity both within and among populations. I then incorporate multi-lake measures of density-dependent life history change into a temperature-based biphasic model of growth and reproduction to predict sustainable rates of mortality for walleye throughout most of their range. Second, the age (or size) structure of a population may also affect recruitment because of positive effects of maternal age on offspring production and survival; however, evidence for these ‘maternal influences’ on recruitment is limited. Using both an analytical model and a meta-analysis of stock-recruitment data from 25 species of exploited marine fish, I show that (i) maximum reproductive rate increased with the mean age of adults in a population, and (ii) the importance of age structure increased with a species’ longevity. I then demonstrate a similar effect of maternal influences on reproductive rate in a detailed study of Lake Erie walleye. By highlighting the importance of fisheries-induced demographic change to recruitment, this thesis provides insight into past and present failures. However, it also demonstrates clearly the benefits of proactive management strategies that (i) identify and respect the limits of exploitation, (ii) protect from exploitation reproductively valuable individuals—principles that apply generally to any freshwater, marine, or terrestrial species that is of recreational, commercial, or conservation value. walleye Sander vitreus maternal influences maternal effects recruitment density-dependence temperature growing degree day age lifespan maturity sustainable cod Gadus morhua egg Ricker reproductive rate demographics stock-recruitment fecundity mortality growth life history 0329
8	Life History, Maternal Quality and the Dynamics of Harvested Fish Stocks Venturelli, Paul Anthony 03 March 2010 (has links) Knowledge of offspring production (recruitment) is fundamental to understanding and forecasting the dynamics of a population. In this thesis, I focus on two demographic characteristics of fish stocks that are important to recruitment: population density and age structure. First, populations produce more recruits at low density, but quantifying this response has proven difficult. Using data from hundreds of populations of walleye (Sander vitreus), an economically important freshwater fish, I demonstrate that the growing-degree-day metric (a temperature index) is better than age at explaining variation in density-dependent growth and maturity both within and among populations. I then incorporate multi-lake measures of density-dependent life history change into a temperature-based biphasic model of growth and reproduction to predict sustainable rates of mortality for walleye throughout most of their range. Second, the age (or size) structure of a population may also affect recruitment because of positive effects of maternal age on offspring production and survival; however, evidence for these ‘maternal influences’ on recruitment is limited. Using both an analytical model and a meta-analysis of stock-recruitment data from 25 species of exploited marine fish, I show that (i) maximum reproductive rate increased with the mean age of adults in a population, and (ii) the importance of age structure increased with a species’ longevity. I then demonstrate a similar effect of maternal influences on reproductive rate in a detailed study of Lake Erie walleye. By highlighting the importance of fisheries-induced demographic change to recruitment, this thesis provides insight into past and present failures. However, it also demonstrates clearly the benefits of proactive management strategies that (i) identify and respect the limits of exploitation, (ii) protect from exploitation reproductively valuable individuals—principles that apply generally to any freshwater, marine, or terrestrial species that is of recreational, commercial, or conservation value. walleye Sander vitreus maternal influences maternal effects recruitment density-dependence temperature growing degree day age lifespan maturity sustainable cod Gadus morhua egg Ricker reproductive rate demographics stock-recruitment fecundity mortality growth life history 0329
9	Hydroacoustic Quantification of Lake Erie Walleye (Sander vitreus)Distribution and Abundance DuFour, Mark R. 18 October 2017 (has links) No description available. Aquatic Sciences Biology Ecology Environmental Science Freshwater Ecology Natural Resource Management Biostatistics

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