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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.
21

Managing nature : a look inside the salmon arena /

Pergola, Tanya Alexandra. January 1999 (has links)
Thesis (Ph. D)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 140-146).
22

Contesting modernism : communities and the pacific salmon revitalization plan

Robertson, Stephen 05 1900 (has links)
This thesis explores the role for social work in addressing government policies that threaten the sustainability of small coastal communities. The response of government and industry to the globalization of trade and resource degradation is at odds with the needs of people. Utilizing a case study methodology the development and implementation of the Pacific Salmon Revitalization Plan is explored. This department of fisheries plan to rationalize the fishery was highly contested on the grounds that it took jobs out of small coastal communities. It was accused of benefiting the large fishing corporations and the urban based fishing fleet, which had the capital to profit from the plan. Concentrated opposition from coastal communities, fishers, advocacy groups and academics was unsuccessful in changing the plan. The assumptions of modernism - expert knowledge, scientific rationality and orthodox economics - as well as distorted communications, were postulated to be behind this lack of success. A post modern analysis suggests that a successful challenge to the plan would have incorporated the local knowledge of fishers and coastal communities within a process of fair and equitable public discourse aimed at reaching intersubjectively mediated understanding. For social work this demonstrates the need to work conjointly with communities and affected groups to identify the modernist assumptions on which policy decisions are based and develop locally derived alternatives to these assumptions. And most importantly, that the focus of social change efforts be on demanding a process for discussion and decision-making that ensures that the concerns of effected individuals will be fairly addressed. / Arts, Faculty of / Social Work, School of / Graduate
23

The anthropogenic influence of shellfish aquaculture and microplastics on juvenile Pacific salmon on the east coast of Vancouver Island

Collicutt, Brenna 09 September 2016 (has links)
In the northeast Pacific, salmon are an integral part of ecology, economics and culture. Nearshore areas, where juvenile salmon reside upon leaving their natal streams, are important habitat during a critical time where growth can determine overall survivorship. With the rise in human development in coastal areas, these valuable habitats are becoming increasingly modified, however, the ecological ramifications are not fully understood. This study focuses on two types of anthropogenic influence including shellfish aquaculture, which modifies intertidal areas by adding structures such as intertidal fencing and anti-predator nets, and plastic marine pollution in the form of microplastics. We beach seined at sites within an area extensively modified for shellfish aquaculture (Baynes Sound) to examine juvenile salmon abundance, condition, feeding intensity and prey at aquaculture and non-aquaculture areas. In addition, we also beach seined, and along the east coast of Vancouver Island to determine the incidence of microplastics in juvenile Chinook salmon and their nearshore environments. No significant differences were found between areas in the abundance, diets, condition or feeding intensity of juvenile Coho and Chinook. Chum had different prey and a higher condition and feeding intensity at aquaculture sites, suggesting that species such as Chum feeding on more benthic prey items have a higher probability of being impacted by shellfish aquaculture modifications and in this case we observed positive effects. Microplastic analysis showed juvenile Chinook salmon contained 1.15 1.41 (SD) microplastics per individual while water and sediment samples had 659.88 520.87 microplastics m-3 and 60.2 63.4 microplastics kg-1 dry weight, respectively. We found no differences in microplastic concentrations in juvenile Chinook and water samples among sites but observed significantly higher concentrations in sediment at our Deep Bay site compared to Nanaimo and Cowichan Bay. These differences may be due to site bathymetry and oceanographic differences facilitating settlement at the Deep Bay site and/or may be a result of differential plastic sources in the area including shellfish farming and a marina. Shellfish aquaculture had negligible or positive effects on juvenile salmon abundance, diet, condition and feeding intensity and Chinook microplastic concentrations were relatively low compared to literature values. Although fitness consequences and ecosystem-wide implications must be addressed in the future, it appears shellfish aquaculture and microplastics are not immediate threats to juvenile Pacific salmon along the east coast of Vancouver Island at this time. However, continued monitoring programs and larger-scale studies should be implemented as shoreline modification and plastic use continues to increase. / Graduate / 2017-08-14
24

One fish, two fish, old fish, new fish: investigating differential distribution of salmon resources in the Pacific Northwest through ancient DNA analysis /

Speller, Camilla F. January 2005 (has links)
Thesis (M.A.) - Simon Fraser University, 2005. / Theses (Dept. of Archaeology) / Simon Fraser University. Also issued in digital format and available on the World Wide Web.
25

History and evolution of salmon aquaculture siting policy in British Columbia

Galland, Daniel 11 1900 (has links)
Salmon aquaculture is the rearing of salmonids for commercial purposes. These practices are typically carried out in saltwater farms located in coastal waters. The process of siting these facilities requires identifying and selecting areas that are economically, socially and environmentally suitable to locate them. Siting salmon aquaculture facilities has become a controversial resource management issue in British Columbia (B.C.), where distance-based criteria ultimately determine the location of these facilities. This thesis focuses on providing insights and concepts to inform and examine the salmon aquaculture facility siting process in B.C. It is argued that regulatory processes and outcomes in the context of a new industry could respond to mechanisms and factors that shape governmental agendas, illustrating how policy can behave reactively rather than in a precautionary manner. In this case, the outcomes of such reactive policies are reflected in siting criteria that yield implicit environmental and socio-economic disadvantages and tradeoffs. This way, siting criteria derive from expert judgements based on best available information while their associated uncertainties may lead to consider less-desirable sites while underestimating or overestimating risks, and overlooking important regional objectives, cumulative impacts and stakeholder values. The thesis further suggests that the future evolution of the salmon aquaculture facility siting process in B.C. could benefit from siting processes that have already been developed and implemented by other sectors. Different lines of reasoning that deal with processes of public negotiation, analytical decision-making and a systems' approach are explored as ways by which the salmon aquaculture facility siting process could evolve in the future toward creating more comprehensive policy.
26

Early marine ecology of Pacific salmon: interactions with sea lice.

Price, Michael Harold Howard 29 November 2011 (has links)
Pacific salmon (Oncorhynchus spp.) are key elements of ecological systems, and play an important role in the cultural foundation of human societies. All species of wild salmon face multiple, simultaneous threats, with habitat degradation likely playing a key role in survival. Open net-pen salmon farms can degrade important nursery marine habitat for wild juvenile salmon by disrupting natural salmonid host-parasite dynamics. The first two chapters in this thesis examine louse parasitism of wild juvenile chum (Oncorhynchus keta), pink (O. gorbuscha), and sockeye salmon (O. nerka) in relation to their marine migration past salmon farms. I compare sites of low and high exposure to salmon farms, and include two areas without farms on British Columbia’s central and north coasts to assess baseline infection levels. Louse prevalence and abundance were lowest and most similar to natural baseline levels at low exposure sites, and highest at high exposure sites in all farm regions. A significantly greater proportion of the lice infecting juvenile chum and pink salmon were Lepeophtheirus salmonis at high exposure sites. Caligus clemensi was the principal louse species infecting all juveniles in areas without salmon farms, and at low exposure sites within salmon farm regions; C. clemensi was also the dominant louse to infect juvenile sockeye that migrated past farms. Mixed-effects modelling results showed that exposure to salmon farms was the most consistent factor to explain the variation in louse infection levels, and support my hypothesis that salmon farms are a major source of sea lice on juvenile wild salmon in regions with salmon farms. I discovered that juvenile sockeye at one particular location within the Georgia Strait hosted unusually high lice levels; this location was situated at a distance from salmon farms, but near a farm salmon processing facility. Upon further investigation, I found live sea lice, Lepeophtheirus salmonis, mucus, and fish tissue in effluent discharged from the processing facility. Sea lice transmitted from this source may pose a threat to wild salmon populations, and the release of potentially untreated offal, including blood water, is of considerable concern. These results form the third chapter in my thesis. Given the challenges facing juvenile salmon in general, and sockeye from the Fraser River in particular (i.e., 2009 was the lowest return on record), and because poor habitat conditions within Georgia Strait are considered the major cause of the recent decline in Fraser River sockeye, this raises the question as to whether food limitations are a factor. The final chapter in my thesis examines the prey assemblage, diet composition, and foraging selectivity of juvenile sockeye, and investigates whether food limitations can be detected during early migration through Georgia Strait. Juvenile sockeye demonstrated high prey diversity, with preference for particular prey. Prey were more concentrated in the north, which may help explain migratory behavior of juveniles through the study region, and temporal similarities in sockeye foraging success may reflect short-term food resource stability. Moreover, I could not find evidence of food limitations that might suggest juvenile sockeye were strongly food deprived during the years of this study. Finally, my thesis explores how best to conserve salmon populations given the multitude of stressors. Because stressors often interact to produce compound effects and unpredictable results, ranking the overall threats in order of severity may not be useful. Instead, the most successful ranking system may be in terms of reducing harm where possible. For juvenile salmon during their early marine migration, risks posed by salmon farms can be more easily mitigated than the far-reaching effects on ocean productivity of climate change and ocean acidification, or predator removal. I recommend we begin here. / Graduate
27

Harbor seals in Hood Canal : predators and prey /

London, Josh M. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 71-77).
28

The effect of dietary fatty acids on body composition, growth, mortality and saltwater tolerance in juvenile coho salmon (Oncorhynchus kisutch)

Bernatsky, Ivor Paul January 1990 (has links)
An experiment was designed to determine whether the response of fish to graded dietary levels of essential fatty acids (n3) was affected by the total dietary lipid concentration. Juvenile coho salmon were fed practical diets varying in lipid source and total lipid content. The diets were fed in duplicate during a 27-week and a 12-week period ran in succession. The effects of the different dietary fatty acid concentrations on body fatty acids composition were determined after each period. The dietary fatty acid classes were expressed either as percent of the dry diet or percent of the dietary lipid. Analysis of the body lipid fatty acid composition was performed for neutral and polar lipid fractions. The effect of dietary fatty acid concentration on growth and mortality was determined over a 12-week growth study (period 2). A 24-hour saltwater challenge was performed at the end of period 2. It was used to examine the effect of dietary fatty acid concentration on saltwater tolerance. Dietary n6 and n3 fatty acids appeared to be selectively incorporated into the body polar lipid pool. Linoleate and linolenate underwent elongation and desaturation which resulted in the inhibition of the elongation and desaturation of 18:ln9. The neutral lipid pool served as a source of n3 fatty acids for the polar lipid when dietary intake was limited by low temperatures during period 1. The body neutral monounsaturated and 18:1 monounsaturated fatty acids consistently reflected the composition of the diet. The n3 fatty acid concentration in the neutral lipid was also directly related to the dietary fatty acid composition during period 2. The effect of dietary fatty acids on the body neutral or polar fatty acid composition did not depend on the manner in which the dietary fatty acids were expressed. There was also no significant effect of dietary total lipid concentration on the relationship between dietary fatty acids and their incorporation into the body lipids. The growth response was difficult to interpret because of the high mortality. There was a significant difference in mortality among treatments. A positive relationship between dietary concentrations of total n3 fatty acids or n3 highly unsaturated fatty acids and mortality became evident following analysis of the regression of mortality as a function of dietary fatty acid composition. The dietary fatty acid composition did not appear to alter the saltwater tolerance of the 1+ coho salmon. / Land and Food Systems, Faculty of / Graduate
29

History and evolution of salmon aquaculture siting policy in British Columbia

Galland, Daniel 11 1900 (has links)
Salmon aquaculture is the rearing of salmonids for commercial purposes. These practices are typically carried out in saltwater farms located in coastal waters. The process of siting these facilities requires identifying and selecting areas that are economically, socially and environmentally suitable to locate them. Siting salmon aquaculture facilities has become a controversial resource management issue in British Columbia (B.C.), where distance-based criteria ultimately determine the location of these facilities. This thesis focuses on providing insights and concepts to inform and examine the salmon aquaculture facility siting process in B.C. It is argued that regulatory processes and outcomes in the context of a new industry could respond to mechanisms and factors that shape governmental agendas, illustrating how policy can behave reactively rather than in a precautionary manner. In this case, the outcomes of such reactive policies are reflected in siting criteria that yield implicit environmental and socio-economic disadvantages and tradeoffs. This way, siting criteria derive from expert judgements based on best available information while their associated uncertainties may lead to consider less-desirable sites while underestimating or overestimating risks, and overlooking important regional objectives, cumulative impacts and stakeholder values. The thesis further suggests that the future evolution of the salmon aquaculture facility siting process in B.C. could benefit from siting processes that have already been developed and implemented by other sectors. Different lines of reasoning that deal with processes of public negotiation, analytical decision-making and a systems' approach are explored as ways by which the salmon aquaculture facility siting process could evolve in the future toward creating more comprehensive policy. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate
30

Becoming A Food Citizen

Hornung, Nicole 01 January 2013 (has links)
Environmental citizenship is positioned as a platform where the rights of social and environmental justice converge with civic engagement and responsibility. As industrialized economies continue to exhaust the limits of finite natural resources and exacerbate conditions of global climate change, scholars have questioned if environmental citizenship models offer a method for deepening obligations to a sustainable movement. In the material culture enjoyed by Western civilizations, existing research supports that an individual’s purchases are seen as an indicator of their values and identities. Consequently the commitment to responsible buying behavior or sustainable consumption is in a sense an expression of eco-citizenship. My thesis offers a critical perspective of Andrew Dobson’s ecological citizenship theory, by asking how sustainable consumption can be conceptualized in the existing political and economic infrastructures. Using a thorough case study of globally traded fish provisions, I investigate the existing barriers for eco-citizens attempting to realize their obligations to sustainable consumption. This analysis allows me to draw conclusions on how these barriers may inhibit ecocitizenship theories and ultimately a sustainable social movement. The structure of this thesis is broken into three parts. First, I define existing theories of ecological citizenship and sustainable consumption, including the theoretical propositions, requirements, and limitations. Secondly, I rely on Dobson’s conception of ecological citizenship and an instrumental case study of Pacific Salmon provisions to illustrate the barriers eco-citizens encounter in the current market and regulatory system. Finally, this paper concludes by proposing individual and institutional changes that will assist in fostering an eco-citizen community and the contribution my findings may have on existing green citizenship research.

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